BEGIN
NHC_ATCF
invest_RENUMBER_al912010_al112010.ren
FSTDA
R
U
040
010
0000
201009081358
NONE
NOTIFY=ATRP
END
INVEST, AL, L, , , , , 11, 2010, DB, O, 2010090718, 9999999999, , , , , , METWATCH, , AL112010
AL, 11, 2010090700, , BEST, 0, 128N, 189W, 25, 1008, DB, 0, , 0, 0, 0, 0,
AL, 11, 2010090706, , BEST, 0, 132N, 195W, 25, 1008, DB, 0, , 0, 0, 0, 0,
AL, 11, 2010090712, , BEST, 0, 137N, 201W, 25, 1008, DB, 0, , 0, 0, 0, 0,
AL, 11, 2010090718, , BEST, 0, 140N, 211W, 25, 1008, DB, 0, , 0, 0, 0, 0, 1010, 150, 60, 0, 0, L, 0, , 0, 0, INVEST, S,
AL, 11, 2010090800, , BEST, 0, 140N, 219W, 25, 1007, DB, 0, , 0, 0, 0, 0, 1011, 150, 60, 0, 0, L, 0, , 0, 0, INVEST, S,
AL, 11, 2010090806, , BEST, 0, 140N, 227W, 30, 1005, DB, 0, , 0, 0, 0, 0, 1010, 150, 50, 0, 0, L, 0, , 0, 0, INVEST, S,
AL, 11, 2010090812, , BEST, 0, 137N, 233W, 30, 1005, DB, 34, NEQ, 0, 0, 0, 0, 1010, 180, 70, 0, 0, L, 0, , 0, 0, INVEST, S,
BEGIN
NHC_ATCF
invest_al112010.invest
FSTDA
R
U
040
010
0000
201009081401
NONE
NOTIFY=ATRP
END
IGOR, AL, L, , , , , 11, 2010, TS, O, 2010090718, 9999999999, , , , , , METWATCH, 1, AL112010
AL, 11, 2010090700, , BEST, 0, 128N, 189W, 25, 1008, DB, 0, , 0, 0, 0, 0,
AL, 11, 2010090706, , BEST, 0, 132N, 195W, 25, 1008, DB, 0, , 0, 0, 0, 0,
AL, 11, 2010090712, , BEST, 0, 137N, 201W, 25, 1008, DB, 0, , 0, 0, 0, 0,
AL, 11, 2010090718, , BEST, 0, 140N, 211W, 25, 1008, DB, 0, , 0, 0, 0, 0, 1010, 150, 60, 0, 0, L, 0, , 0, 0, INVEST, S,
AL, 11, 2010090800, , BEST, 0, 140N, 219W, 25, 1007, DB, 0, , 0, 0, 0, 0, 1011, 150, 60, 0, 0, L, 0, , 0, 0, INVEST, S,
AL, 11, 2010090806, , BEST, 0, 140N, 227W, 30, 1006, TD, 0, , 0, 0, 0, 0, 1010, 150, 50, 0, 0, L, 0, , 0, 0, INVEST, S,
AL, 11, 2010090812, , BEST, 0, 137N, 233W, 35, 1005, TS, 34, NEQ, 0, 45, 45, 30, 1010, 180, 30, 0, 0, L, 0, , 0, 0, IGOR, S,
000
WTNT41 KNHC 081459
TCDAT1
TROPICAL STORM IGOR DISCUSSION NUMBER 1
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL112010
1100 AM AST WED SEP 08 2010
THE LOW OVER THE FAR EASTERN TROPICAL ATLANTIC OCEAN HAS BECOME
BETTER DEFINED AND DEEP CONVECTION NEAR THE CENTER HAS PERSISTED
LONG ENOUGH FOR THIS SYSTEM TO BE CONSIDERED A TROPICAL CYCLONE. A
1042 UTC ASCAT PASS SHOWED WINDS OF 35 KT...AND THE INITIAL
INTENSITY WILL BE SET TO THAT VALUE. EASTERLY SHEAR IS PRESENT
OVER IGOR...BUT IS FORECAST TO LIGHTEN IN A DAY OR SO. ALL
RELIABLE MODELS SHOW INTENSIFICATION INTO A HURRICANE IN THE NEXT
SEVERAL DAYS. BECAUSE OF THE SHEAR...THE NHC INTENSITY FORECAST
WILL ONLY SHOW RELATIVELY SLOW STRENGTHENING...BELOW THE GUIDANCE
INITIALLY...BUT THE FORECAST ENDS UP CLOSE TO THE CONSENSUS AT DAY
5. IF THE UPPER ANTICYCLONE PATTERN SEEN IN MOST OF THE GLOBAL
MODELS VERIFY...THE OFFICIAL FORECAST COULD BE CONSERVATIVE IN THE
LATTER PART OF THE FORECAST PERIOD.
THE INITIAL MOTION IS 265/7. A MID-LEVEL RIDGE OVER THE EASTERN
ATLANTIC OCEAN IS FORECAST TO STRENGTHEN OVER THE NEXT FEW
DAYS...WHICH SHOULD CAUSE A WESTWARD MOTION AT AN INCREASING
FORWARD SPEED. AT THE END OF THE PERIOD...A TROUGH OVER THE
CENTRAL ATLANTIC COULD WEAKEN THE RIDGE...FORCING THE STORM TO MOVE
MORE TO THE WEST-NORTHWEST. THE MODEL GUIDANCE IS IN RELATIVELY
GOOD AGREEMENT ON THIS SCENARIO...ALTHOUGH THERE IS SOME SHORT-TERM
UNCERTAINTY ON HOW IGOR WILL INTERACT WITH THE LARGE CONVECTIVE
SYSTEM TO THE NORTHEAST OF THE STORM. THE NHC FORECAST IS NEAR OR
SLIGHTLY SOUTH OF THE MODEL CONSENSUS.
FORECAST POSITIONS AND MAX WINDS
INITIAL 08/1500Z 13.7N 23.5W 35 KT
12HR VT 09/0000Z 13.7N 24.6W 40 KT
24HR VT 09/1200Z 13.8N 26.6W 45 KT
36HR VT 10/0000Z 14.0N 29.0W 50 KT
48HR VT 10/1200Z 14.5N 31.5W 55 KT
72HR VT 11/1200Z 15.5N 36.5W 65 KT
96HR VT 12/1200Z 16.8N 41.2W 75 KT
120HR VT 13/1200Z 18.0N 46.0W 85 KT
$$
FORECASTER BLAKE/PASCH
000
WTNT41 KNHC 090837
TCDAT1
TROPICAL STORM IGOR DISCUSSION NUMBER 4
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL112010
500 AM AST THU SEP 09 2010
THE CLOUD PATTERN HAS DETERIORATED DURING THE PAST 6 HOURS AND
CONTINUES TO BE HIGHLY SHEARED. NEITHER SATELLITE INTENSITY
ESTIMATES NOR ASCAT MEASUREMENTS SUPPORT TROPICAL STORM INTENSITY.
THE INITIAL INTENSITY HAS BEEN ADJUSTED DOWN TO 35 KNOTS AND THIS
ESTIMATE IS GENEROUS. IGOR COULD WEAKEN A LITTLE MORE TODAY BUT
GIVEN THAT THE CYCLONE STILL HAS A LARGE CIRCULATION AND IS MOVING
TOWARD A MORE FAVORABLE ENVIRONMENT OF LOWER SHEAR AND WARMER
OCEAN...A GRADUAL STRENGTHENING COULD BEGIN IN 24 HOUR OR SO. IGOR
IS STILL FORECAST TO BECOME A HURRICANE IN ABOUT 3 DAYS.
FIRST VISIBLE SATELLITE IMAGES INDICATE THAT THE CENTER IS STILL
LOCATED SOUTH OF THE CAPE VERDE ISLANDS SUGGESTING THAT IGOR HAS
BEEN MEANDERING DURING THE PAST FEW HOURS. HOWEVER...THE LARGE
CIRCULATION SHOULD BEGIN TO MOVE SLOWLY TOWARD THE WEST-NORTHWEST
LATER TODAY. THE STEERING PATTERN OVER THE ATLANTIC HAS BEEN QUITE
PERSISTENT AND CONSISTS OF A SUBTROPICAL RIDGE OVER THE EASTERN
PART OF THE BASIN AND A BROAD TROUGH OSCILLATING BETWEEN THE
EASTERN UNITED STATES AND THE WESTERN PORTION OF THE BASIN. THIS
STEERING PATTERN WHICH IS FORECAST BY THE GLOBAL MODELS TO
CONTINUE...WOULD FAVOR A GENERAL WESTWARD MOTION WITH AN INCREASE
IN FORWARD SPEED DURING THE NEXT DAY OR TWO AND THEN A TURN MORE TO
THE WEST-NORTHWEST BY THE END OF THE FORECAST PERIOD. TRACK
GUIDANCE DEPICTS THIS SCENARIO WHICH IS REFLECTED IN THE OFFICIAL
FORECAST.
FORECAST POSITIONS AND MAX WINDS
INITIAL 09/0900Z 13.8N 24.3W 35 KT
12HR VT 09/1800Z 14.0N 25.3W 30 KT
24HR VT 10/0600Z 15.0N 28.0W 40 KT
36HR VT 10/1800Z 16.0N 31.0W 45 KT
48HR VT 11/0600Z 16.5N 34.0W 55 KT
72HR VT 12/0600Z 17.0N 40.0W 65 KT
96HR VT 13/0600Z 18.0N 44.5W 75 KT
120HR VT 14/0600Z 19.5N 49.0W 85 KT
$$
FORECASTER AVILA
000
WTNT31 KNHC 091131
TCPAT1
BULLETIN
TROPICAL STORM IGOR INTERMEDIATE ADVISORY NUMBER 4A
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL112010
800 AM AST THU SEP 09 2010
...IGOR A WEAK TROPICAL STORM...DRIFTING NORTHWARD...
DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 800 AM AST...1200 UTC...THE CENTER OF TROPICAL STORM IGOR WAS
LOCATED NEAR LATITUDE 14.1 NORTH...LONGITUDE 24.2 WEST. IGOR IS
DRIFTING NORTHWARD AT ABOUT 2 MPH...4 KM/HR. IGOR IS EXPECTED TO
TURN WESTWARD OR WEST-NORTHWESTWARD WITH AN INCREASE IN FORWARD
SPEED DURING THE NEXT DAY OR TWO.
MAXIMUM SUSTAINED WINDS REMAIN NEAR 40 MPH...65 KM/HR...WITH HIGHER
GUSTS. LITTLE CHANGE IN INTENSITY IS EXPECTED TODAY BUT SOME
STRENGTHENING IS FORECAST TO BEGIN ON FRIDAY.
TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 50 MILES...85 KM...
MAINLY TO THE SOUTH OF THE CENTER.
ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB...29.71 INCHES.
HAZARDS AFFECTING LAND
----------------------
WINDS... TROPICAL STORM CONDITIONS ARE POSSIBLE IN THE SOUTHERN CAPE
VERDE ISLANDS TODAY. THESE CONDITIONS ARE EXPECTED TO END LATER
TODAY.
NEXT ADVISORY
-------------
NEXT COMPLETE ADVISORY...1100 AM AST.
$$
FORECASTER CANGIALOSI/BRENNAN
Un poco de humor con nuestro IGOR ;D ;D ;D
[youtube]r4VDuLuE52s[/youtube]
In english ;)
[youtube]XaPZZJVDx6Y[/youtube]
000
WTNT41 KNHC 091431
TCDAT1
TROPICAL STORM IGOR DISCUSSION NUMBER 5
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL112010
1100 AM AST THU SEP 09 2010
DEEP CONVECTION FORMED NEAR THE LOW-LEVEL CENTER OF IGOR AROUND 1030
UTC...AND HAS EXPANDED SINCE THAT TIME. HOWEVER...THIS CONVECTION
REMAINS WEST OF THE CENTER DUE TO ABOUT 20 KT OF EASTERLY SHEAR
...AS SHOWN BY UW-CIMSS ANALYSES. ALTHOUGH AN ASCAT PASS AROUND
0000 UTC ONLY SHOWED MAXIMUM WINDS OF 25-30 KT...THE WINDS ARE
ASSUMED TO BE A LITTLE STRONGER NOW DUE TO THE INCREASE IN
CONVECTION. THEREFORE...IGOR WILL REMAIN A TROPICAL STORM WITH AN
INITIAL WIND SPEED ESTIMATE OF 35 KT. THE SHIPS MODEL SHOWS THE
EASTERLY SHEAR DECREASING OVER THE NEXT FEW DAYS. THIS...COMBINED
WITH WARM WATERS AND A RELATIVELY MOIST ATMOSPHERE SHOULD ALLOW FOR
STEADY INTENSIFICATION. THE STATISTICAL AND DYNAMICAL INTENSITY
MODELS BRING IGOR TO HURRICANE STRENGTH IN ABOUT 3 DAYS AND SHOW
ADDITIONAL STRENGTHENING THEREAFTER. THE NHC OFFICIAL FORECAST IS
SIMILAR TO THE PREVIOUS ONE AND IS IN CLOSEST AGREEMENT WITH THE
STATISTICAL GUIDANCE.
IGOR HAS BEEN GENERALLY MOVING NORTH-NORTHWESTWARD DURING THE LAST
SEVERAL HOURS...AND THE 6-HOUR INITIAL MOTION ESTIMATE IS 330/5.
HOWEVER...THE LAST FEW FEW VISIBLE IMAGES SUGGEST A SLIGHTLY FASTER
NORTHWESTWARD MOTION. NOW THAT IGOR APPEARS TO HAVE ABSORBED THE
WEAK LOW THAT HAD BEEN IN ITS VICINITY...A LOW- TO MID-LEVEL RIDGE
NORTH AND NORTHEAST OF IGOR SHOULD STEER THE CYCLONE WESTWARD OR
WEST-NORTHWESTWARD WITH A GRADUAL INCREASE IN FORWARD SPEED. BY
THE END OF THE PERIOD...THE GLOBAL MODELS SHOW IGOR NEARING A
CENTRAL ATLANTIC TROUGH WHICH SHOULD CAUSE A NORTHWESTWARD TURN.
THE OFFICIAL FORECAST IS ADJUSTED TO THE NORTH IN THE SHORT-TERM
DUE TO THE INITIAL POSITION AND MOTION...AND IS A LITTLE SLOWER AT
THE END OF THE FORECAST PERIOD AS SUGGESTED BY THE GUIDANCE SUITE.
FORECAST POSITIONS AND MAX WINDS
INITIAL 09/1500Z 14.7N 24.8W 35 KT
12HR VT 10/0000Z 15.0N 26.3W 35 KT
24HR VT 10/1200Z 15.8N 29.0W 40 KT
36HR VT 11/0000Z 16.4N 32.0W 50 KT
48HR VT 11/1200Z 16.7N 35.0W 60 KT
72HR VT 12/1200Z 17.3N 40.4W 70 KT
96HR VT 13/1200Z 18.5N 44.5W 80 KT
120HR VT 14/1200Z 20.0N 48.5W 85 KT
$$
FORECASTER CANGIALOSI/BRENNAN
...IGOR MOVING ERRATICALLY...
000
WTNT41 KNHC 092038
TCDAT1
TROPICAL DEPRESSION IGOR DISCUSSION NUMBER 6
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL112010
500 PM AST THU SEP 09 2010
THE DEEP CONVECTION THAT WAS LOCATED NEAR THE CENTER EARLIER TODAY
HAS ERODED AND NOW TAKES THE SHAPE OF A CURVED BAND OVER
THE WESTERN SEMICIRCLE...SITUATED ABOUT 90 N MI WEST OF THE CENTER.
THIS ASYMMETRIC CONVECTIVE PATTERN IS DUE TO ABOUT 20-25 KT OF
EASTERLY SHEAR. SINCE THE CONVECTION IS WELL REMOVED FROM THE
CENTER AND BECAUSE EARLIER ASCAT DATA DID NOT SHOW WINDS OF
TROPICAL STORM FORCE...IGOR IS BEING DOWNGRADED TO A TROPICAL
DEPRESSION AT THIS TIME. ALTHOUGH IGOR HAS WEAKENED TODAY...
INTENSIFICATION IS STILL EXPECTED DURING THE FORECAST PERIOD. THE
SHIPS MODEL SHOWS THE SHEAR DECREASING SIGNIFICANTLY DURING THE
NEXT COUPLE OF DAYS. THIS...IN COMBINATION WITH A RELATIVELY WARM
OCEAN AND MOIST ATMOSPHERE SHOULD ALLOW IGOR TO STRENGTHEN.
HOWEVER...THE CYCLONE WILL BE PASSING THROUGH AN AREA OF SLIGHTLY
COOLER SSTS IN A COUPLE DAYS...SO THE NEW OFFICIAL FORECAST SHOWS A
MORE GRADUAL STRENGTHENING THAN THE PREVIOUS ONE...BUT STILL MAKES
IGOR A HURRICANE IN 3 DAYS.
THE LOW-LEVEL CENTER HAS BEEN RACING NORTHWESTWARD DURING
THE LAST FEW HOURS...AND IS NOW LOCATED NORTH OF THE
PREVIOUS FORECAST TRACK. HOWEVER...A WEST-NORTHWESTWARD MOTION IS
EXPECTED TO BEGIN SOON AND PERSIST FOR THE NEXT FEW DAYS AS A LOW-
TO MID-LEVEL RIDGE LOCATED NORTH AND NORTHEAST OF IGOR BECOMES
THE PRIMARY STEERING MECHANISM. THE GLOBAL MODELS SHOW IGOR
APPROACHING A LARGE BUT RATHER FLAT TROUGH IN 4 TO 5 DAYS...WHICH
SHOULD CAUSE THE CYCLONE TO TURN NORTHWESTWARD WITH A DECREASE IN
FORWARD SPEED. THE NEW NHC TRACK FORECAST IS ADJUSTED TO THE NORTH
IN THE SHORT-TERM BUT IS OTHERWISE SIMILAR TO THE PREVIOUS ONE.
FORECAST POSITIONS AND MAX WINDS
INITIAL 09/2100Z 16.0N 26.4W 30 KT
12HR VT 10/0600Z 16.7N 27.9W 30 KT
24HR VT 10/1800Z 17.3N 30.8W 35 KT
36HR VT 11/0600Z 17.5N 33.9W 45 KT
48HR VT 11/1800Z 17.8N 36.8W 55 KT
72HR VT 12/1800Z 18.4N 41.9W 65 KT
96HR VT 13/1800Z 19.5N 46.0W 75 KT
120HR VT 14/1800Z 21.0N 49.0W 85 KT
$$
FORECASTER CANGIALOSI/BRENNAN
000
WTNT41 KNHC 100833
TCDAT1
TROPICAL DEPRESSION IGOR DISCUSSION NUMBER 8
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL112010
500 AM AST FRI SEP 10 2010
IGOR IS STILL STRONGLY SHEARED WITH THE CENTER LOCATED TO THE EAST
OF A STRONG AND CIRCULAR CONVECTIVE MASS AS OBSERVED IN BOTH
MICROWAVE DATA AND CONVENTIONAL IR IMAGERY. AS WE SPEAK...FIRST
METEOSAT VISIBLE IMAGE CONFIRMED THAT THE CENTER IS EXPOSED BUT
BETTER DEFINED. INITIAL INTENSITY IS KEPT AT 30 KNOTS BUT IT WILL
NOT TAKE MUCH FOR IGOR TO REGAIN TROPICAL STORM STATUS AND IN
FACT...THIS IS EXPECTED TO OCCUR LATER TODAY. THE CYCLONE IS
ESCAPING FROM THE MONSOON-TYPE LOW-LEVEL SOUTHWESTERLY FLOW AND IS
BECOMING EMBEDDED IN THE TRADE WINDS. THIS WOULD RESULT IN LESS
SHEAR AND WILL LEAD TO INTENSIFICATION...AS INDICATED IN THE
OFFICIAL FORECAST. GLOBAL MODELS FORECAST IGOR TO BE A LARGE
HURRICANE OVER THE CENTRAL TROPICAL ATLANTIC BY THE END OF THE
FORECAST PERIOD AND BEYOND.
THE INITIAL MOTION IS UNCERTAIN SINCE IT WAS DIFFICULT TO FOLLOW
VARIOUS LOW-LEVEL CENTERS THAT WERE ROTATING AROUND A LARGER GYRE
DURING THE PAST 12 HOURS OR SO. THE BEST ESTIMATE IS 280 DEGREES AT
11 TO 12 KNOTS. THE SUBTROPICAL RIDGE IS FORECAST TO BUILD WESTWARD
AND THIS PATTERN SHOULD STEER IGOR WESTWARD WITH AN INCREASE IN
FORWARD SPEED DURING THE NEXT 3 TO 4 DAYS. BY THE END OF THE
FORECAST PERIOD...IGOR SHOULD BE ON THE SOUTHWESTERN EDGE OF THE
RIDGE AND SHOULD BEGIN TO GAIN MORE LATITUDE. TRACK GUIDANCE
OVERALL IS FAIRLY CONSISTENT IN TAKING IGOR WESTWARD. HOWEVER...A
COUPLE OF MODELS FORECAST A STRONGER SUBTROPICAL RIDGE TO THE NORTH
OF THE CYCLONE...RESULTING IN A MORE PRONOUNCED WESTWARD TRACK. THE
OFFICIAL FORECAST IS HEAVILY BIASED TOWARD THE GFS AND THE ECMWF
MODELS WHICH FORECAST A MODERATE BUT A MORE REALISTIC SUBTROPICAL
RIDGE TO THE NORTH.
FORECAST POSITIONS AND MAX WINDS
INITIAL 10/0900Z 16.0N 29.3W 30 KT
12HR VT 10/1800Z 16.0N 31.1W 35 KT
24HR VT 11/0600Z 16.3N 34.2W 40 KT
36HR VT 11/1800Z 16.5N 37.5W 45 KT
48HR VT 12/0600Z 16.8N 40.2W 55 KT
72HR VT 13/0600Z 17.0N 45.0W 65 KT
96HR VT 14/0600Z 18.0N 49.5W 80 KT
120HR VT 15/0600Z 19.5N 53.5W 90 KT
$$
FORECASTER AVILA
BEGIN
NHC_ATCF
invest_al112010.invest
FSTDA
R
U
040
010
0000
201009101252
NONE
NOTIFY=ATRP
END
IGOR, AL, L, , , , , 11, 2010, TS, O, 2010090718, 9999999999, , , , , , WARNING, 1, AL112010
AL, 11, 2010090700, , BEST, 0, 128N, 189W, 25, 1008, DB, 0, , 0, 0, 0, 0,
AL, 11, 2010090706, , BEST, 0, 132N, 195W, 25, 1008, DB, 0, , 0, 0, 0, 0,
AL, 11, 2010090712, , BEST, 0, 137N, 201W, 25, 1008, DB, 0, , 0, 0, 0, 0,
AL, 11, 2010090718, , BEST, 0, 140N, 211W, 25, 1008, DB, 0, , 0, 0, 0, 0, 1010, 150, 60, 0, 0, L, 0, , 0, 0, INVEST, S,
AL, 11, 2010090800, , BEST, 0, 140N, 219W, 25, 1007, DB, 0, , 0, 0, 0, 0, 1011, 150, 60, 0, 0, L, 0, , 0, 0, INVEST, S,
AL, 11, 2010090806, , BEST, 0, 139N, 226W, 30, 1006, TD, 0, , 0, 0, 0, 0, 1010, 150, 50, 0, 0, L, 0, , 0, 0, INVEST, S,
AL, 11, 2010090812, , BEST, 0, 138N, 233W, 40, 1005, TS, 34, NEQ, 0, 45, 45, 30, 1010, 180, 30, 45, 0, L, 0, , 0, 0, IGOR, S,
AL, 11, 2010090818, , BEST, 0, 138N, 237W, 40, 1005, TS, 34, NEQ, 0, 45, 45, 30, 1010, 180, 30, 50, 0, L, 0, , 0, 0, IGOR, S,
AL, 11, 2010090900, , BEST, 0, 138N, 242W, 35, 1005, TS, 34, NEQ, 0, 45, 45, 30, 1010, 125, 30, 50, 0, L, 0, , 0, 0, IGOR, S, 12, NEQ, 0, 45, 45, 30
AL, 11, 2010090906, , BEST, 0, 138N, 243W, 35, 1006, TS, 34, NEQ, 0, 45, 45, 30, 1010, 125, 30, 45, 0, L, 0, , 0, 0, IGOR, S, 12, NEQ, 0, 45, 45, 30
AL, 11, 2010090912, , BEST, 0, 142N, 245W, 35, 1006, TS, 34, NEQ, 0, 0, 0, 30, 1011, 160, 30, 45, 0, L, 0, , 0, 0, IGOR, S, 12, NEQ, 30, 60, 60, 60
AL, 11, 2010090918, , BEST, 0, 149N, 263W, 35, 1004, TD, 34, NEQ, 0, 0, 0, 30, 1009, 90, 30, 45, 0, L, 0, , 0, 0, IGOR, S, 12, NEQ, 30, 60, 60, 60
AL, 11, 2010091000, , BEST, 0, 153N, 274W, 30, 1004, TD, 0, , 0, 0, 0, 0, 1008, 90, 30, 40, 0, L, 0, , 0, 0, IGOR, S, 12, NEQ, 30, 45, 30, 30
AL, 11, 2010091006, , BEST, 0, 159N, 287W, 30, 1004, TD, 0, , 0, 0, 0, 0, 1008, 90, 30, 40, 0, L, 0, , 0, 0, IGOR, S,
AL, 11, 2010091012, , BEST, 0, 163N, 303W, 35, 1004, TS, 34, NEQ, 0, 0, 30, 30, 1012, 200, 30, 0, 0, L, 0, , 0, 0, IGOR, M,
000
WTNT41 KNHC 101455
TCDAT1
TROPICAL STORM IGOR DISCUSSION NUMBER 9
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL112010
1100 AM AST FRI SEP 10 2010
IGOR REMAINS A SHEARED TROPICAL CYCLONE. DURING THE PAST FEW
HOURS...HOWEVER...THE SHEAR HAS BEGUN TO SHOW SIGNS OF ABATING AND
THE LOW-LEVEL CENTER IS NOW FARTHER INTO THE EASTERN PORTION OF THE
CENTRAL DEEP CONVECTION. THE UPGRADE TO STORM STATUS IS BASED ON A
SATELLITE INTENSITY ESTIMATE OF 35 KT FROM TAFB AND A 47-KT
UW-CIMSS 3-HR AVERAGE ADT.
THE INITIAL MOTION IS 280/14. THE INITIAL POSITION AND MOTION ARE
STILL SOMEWHAT UNCERTAIN DUE TO MULTIPLE CIRCULATIONS ROTATING
AROUND THE CENTER OF A LARGER CYCLONIC GYRE. HOWEVER...THE MOTION
IS EXPECTED TO BE BASICALLY WESTWARD FOR THE NEXT 96 HOURS OR SO
ALONG THE SOUTHERN PERIPHERY OF A STRONG SUBTROPICAL RIDGE LOCATED
TO THE NORTH OF THE CYCLONE. BY DAY 5...A SERIES OF WEAK SHORTWAVE
TROUGHS MOVING THROUGH THE BASE OF A BROAD LONGWAVE TROUGH FORECAST
TO BE OFF THE U.S. EAST COAST IS FORECAST BY ALL OF THE GLOBAL
MODELS TO CREATE A WEAKNESS IN THE RIDGE BETWEEN 50W-60W LONGITUDE.
THIS IS EXPECTED TO WEAKEN THE STEERING FLOW AND CAUSE IGOR TO SLOW
DOWN AND ALSO TURN WEST-NORTHWESTWARD. THE OFFICIAL FORECAST TRACK
IS SIMILAR TO THE PREVIOUS ADVISORY AND THE TVCN MODEL CONSENSUS.
CURRENT SHEAR ANALYSES FROM SHIPS AND UW-CIMSS...ALONG WITH WATER
VAPOR WINDS...INDICATE THE VERTICAL SHEAR ACROSS IGOR HAS DECREASED
FROM 20 KT DOWN TO 10 KT DURING THE PAST 24 HOURS. THIS DECEASING
SHEAR TENDENCY IS EXPECTED TO CONTINUE THROUGHOUT THE FORECAST
PERIOD AS IGOR MOVES OVER GRADUALLY INCREASING SSTS...ESPECIALLY
AFTER 48 HOURS. THE RESULT SHOULD BE STEADY INTENSIFICATION WITH
IGOR POSSIBLY REACHING HURRICANE STATUS ON SUNDAY AND MAJOR
HURRICANE STATUS BY DAY 5...AS INDICATED BY THE SHIPS...GFDL...AND
HWRF MODELS. THE OFFICIAL INTENSITY FORECAST IS A LITTLE BELOW THE
GUIDANCE THROUGH 48 HOURS DUE TO UNCERTAINTY ABOUT WHEN IGOR WILL
DEVELOP A CONSOLIDATED CENTER OF CIRCULATION...BUT IS CLOSE TO THE
GUIDANCE THEREAFTER.
FORECAST POSITIONS AND MAX WINDS
INITIAL 10/1500Z 16.4N 31.0W 35 KT
12HR VT 11/0000Z 16.6N 33.2W 40 KT
24HR VT 11/1200Z 16.8N 36.2W 45 KT
36HR VT 12/0000Z 17.0N 39.2W 50 KT
48HR VT 12/1200Z 17.1N 41.7W 60 KT
72HR VT 13/1200Z 17.3N 46.2W 70 KT
96HR VT 14/1200Z 18.2N 50.3W 85 KT
120HR VT 15/1200Z 19.5N 53.5W 95 KT
$$
FORECASTER STEWART
Buenísima esa imagen. A ver si finalmente el ECMWF no exageraba y vemos el primer cat.5 de la temporada...
Buenísima esa imagen. A ver si finalmente el ECMWF no exageraba y vemos el primer cat.5 de la temporada...
Una pregunta con miga, Santi: ¿sabes de algún categoría 5 que se haya formado fuera del GOM o del Caribe? ??? ??? ??? Yo es que no recuerdo ningún caso...
000
WTNT41 KNHC 102044
TCDAT1
TROPICAL STORM IGOR DISCUSSION NUMBER 10
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL112010
500 PM AST FRI SEP 10 2010
THE UPPER-LEVEL SHEAR THAT HAS BEEN PLAGUING IGOR FOR THE PAST
SEVERAL DAYS HAS FINALLY STARTED TO ABATE AND CIRRUS OUTFLOW HAS
NOW BECOME PRONOUNCED IN ALL QUADRANTS. HOWEVER...SOME MID-LEVEL
SHEAR AND DRY AIR ENTRAINMENT IS STILL AFFECTING THE CYCLONE...
WHICH HAS RESULTED IN A VERY ASYMMETRIC CONVECTIVE CLOUD PATTERN
WITH THE LOW-LEVEL CENTER DISPLACED AT LEAST 30 NMI TO THE EAST OF
THE COLDEST CLOUD TOPS. INTENSITY ESTIMATES ARE 30 KT FROM SAB...55
KT FROM TAFB...AND UW-CIMSS 3-HR AVERAGE ADT VALUES OF 49 KT AND
AMSU ESTIMATES OF 53 KT. THE INITIAL INTENSITY HAS BEEN
CONSERVATIVELY INCREASED TO 40 KT...WHICH WILL BE TOO LOW IF THE
LOW-LEVEL CENTER IS ACTUALLY CLOSER TO THE DEEP CONVECTION.
THE INITIAL MOTION IS 280/18. THERE IS NO CHANGE TO THE PREVIOUS
TRACK FORECAST OR REASONING. IGOR IS EXPECTED TO MOVE WESTWARD...
ACCOMPANIED BY A GRADUAL DECREASE IN FORWARD SPEED...FOR THE NEXT 96
HOURS AS THE CYCLONE MOVES ALONG THE SOUTHERN PERIPHERY OF A LARGE
AND STRONG SUBTROPICAL RIDGE SITUATED TO THE NORTH. BY DAY 5...A
BROAD LONGWAVE TROUGH IS FORECAST TO MOVE OFF THE U.S. EAST COAST
AND CREATE A WEAKNESS IN THE RIDGE TO THE NORTHEAST OF THE LESSER
ANTILLES. THIS SHOULD CAUSE THE STEERING FLOW TO WEAKEN AND ALLOW
WHAT IS EXPECTED TO BE A LARGE HURRICANE IGOR AT THAT TIME TO
GRADUALLY TURN WEST-NORTHWESTWARD. THE LATEST MODEL GUIDANCE IS
MORE TIGHTLY PACKED AROUND THE PREVIOUS NHC TRACK...ESPECIALLY AT
DAYS 4 AND 5. IN PARTICULAR...THE GFDL AND ECMWF SHOW LESS OF A
NORTHWARD TURN THAT MIGHT BE RELATED TO A FLATTER LONGWAVE TROUGH
IN THE LATEST GLOBAL RUNS. THE OFFICIAL FORECAST TRACK REQUIRES
LITTLE CHANGE AND IS AN EXTENSION OF THE PREVIOUS ADVISORY.
THE VERTICAL SHEAR IS EXPECTED TO CONTINUE TO DECREASE TO 5 TO 10 KT
FOR THE NEXT 5 DAYS. THIS FAVORABLE UPPER-LEVEL ENVIRONMENT...IN
CONJUNCTION WITH SSTS INCREASING TO 29C BY THE END OF THE FORECAST
PERIOD...SHOULD RESULT IN STEADY INTENSIFICATION. IGOR IS EXPECTED
TO REACH HURRICANE STATUS BY SUNDAY AND MAJOR HURRICANE STATUS BY
DAYS 4 OR 5. THIS SCENARIO IS SUPPORTED BY THE SHIPS...LGEM...
HWRF...AND GFDL MODELS.
FORECAST POSITIONS AND MAX WINDS
INITIAL 10/2100Z 16.7N 33.3W 40 KT
12HR VT 11/0600Z 16.8N 35.4W 45 KT
24HR VT 11/1800Z 17.1N 38.4W 50 KT
36HR VT 12/0600Z 17.2N 41.0W 60 KT
48HR VT 12/1800Z 17.3N 43.4W 70 KT
72HR VT 13/1800Z 17.7N 47.8W 80 KT
96HR VT 14/1800Z 18.7N 51.6W 90 KT
120HR VT 15/1800Z 20.0N 55.0W 105 KT
$$
FORECASTER STEWART
000
WTNT41 KNHC 110835
TCDAT1
TROPICAL STORM IGOR DISCUSSION NUMBER 12
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL112010
500 AM AST SAT SEP 11 2010
IGOR IS STRENGTHENING AND IN FACT...THERE WAS A PERIOD FOR ABOUT TWO
HOURS...BETWEEN 04 AND 06 UTC THAT A SMALL EYE-LIKE FEATURE BECAME
APPARENT ON SATELLITE. HOWEVER...SINCE THEN...SUCH FEATURE HAS
BECOME INTERMITTENT...OTHERWISE I COULD HAVE DECLARED IGOR A
HURRICANE. ALTHOUGH THE CLOUD PATTERN IS BETTER ORGANIZED...THE
OVERALL CONVECTION HAS DECREASED A LITTLE AND NOW CONSISTS OF TWO
WELL-DEFINED CYCLONICALLY CURVED BANDS LOCATED PRIMARILY TO THE
SOUTH OF THE CENTER. THE OUTFLOW HAS BECOME ESTABLISHED IN ALL
QUADRANTS. BASED ON A BLEND OF T-NUMBERS FROM TAFB AND SAB WHICH
ARE 4.0 AND 3.5 ON THE DVORAK SCALE...THE INITIAL INTENSITY HAS
BEEN INCREASED TO 60 KNOTS. GIVEN THE CURRENT INTENSITY TREND...THE
CYCLONE WILL LIKELY BECOME A HURRICANE LATER TODAY. ALL OF THE
ENVIRONMENTAL PARAMETERS APPEAR TO BE FAVORABLE FOR IGOR TO
INTENSIFY...AND THE FORECAST CALLS FOR IGOR TO BE AN INTENSE
HURRICANE IN ABOUT 3 DAYS. GLOBAL MODELS SUGGEST THAT IGOR COULD
ALSO BECOME LARGE.
IGOR IS MOVING TOWARD TOWARD THE WEST OR 270 DEGREES AT 18 KNOTS.
THIS IS BASED ON THE MOTION OF THE EYE-LIKE FEATURE AND CONTINUITY.
THE CYCLONE IS BEING STEERED BY A BUILDING SUBTROPICAL RIDGE OVER
THE EASTERN ATLANTIC...AND THIS PATTERN IS FORECAST BY GLOBAL
MODELS TO PERSIST. ON THIS BASIS...THE OFFICIAL FORECAST CALLS FOR
A GENERAL WESTWARD MOTION FOR THE NEXT 3 DAYS OR SO. BY THEN...IGOR
WILL BE REACHING THE SOUTHWESTERN EDGE OF THE SUBTROPICAL HIGH
WHERE THE STEERING CURRENTS ARE WEAKER...AND BEGIN TO APPROACH A
BROAD TROUGH OVER THE WESTERN ATLANTIC. THIS PATTERN SHOULD FORCE
IGOR TO SLOW DOWN AND BEGIN TO TURN MORE TO THE WEST-NORTHWEST AND
NORTHWEST. THE TRACK FORECAST IS VERY CLOSE TO THE CONSENSUS AND
BIASED TO THE ECMWF AND THE GFS.
FORECAST POSITIONS AND MAX WINDS
INITIAL 11/0900Z 17.1N 37.8W 60 KT
12HR VT 11/1800Z 17.1N 40.2W 70 KT
24HR VT 12/0600Z 17.2N 43.1W 75 KT
36HR VT 12/1800Z 17.4N 46.0W 80 KT
48HR VT 13/0600Z 17.5N 48.5W 90 KT
72HR VT 14/0600Z 17.5N 52.5W 100 KT
96HR VT 15/0600Z 18.5N 55.5W 100 KT
120HR VT 16/0600Z 20.5N 59.0W 100 KT
$$
FORECASTER AVILA
Está claro que si está temporada no está siendo explosiva es por culpa del aire seco, verdadero handicap este año... ¿Qué factores harán que esté más o menos presente a lo largo de una temporada? ??? ??? ??? Se supone que una parte del aire seco es el que va asociado al SAL. Pero también aire seco de origen estratosférico, que quizá pueda colarse en la troposfera debido a las turbulencias que generan las borrascas, sea cual sea el nivel que ocupen (borrascas que ocupen todo el perfil troposférico, o sólo las que ocupan parcelas superiores, como las DANAs). Si hay una gran actividad ciclónica extratropical en una cuenca, a lo mejor hay más aire seco de origen estratosférico dando por saco... ¿Cómo lo ves?Pues esa pregunta me la he hecho yo esta mañana, y me han contestado que es debido a las altas presiones que dominan desde hace dos semanas el Atlántico Central, supongo que por un efecto de subsidencia que hace que descienda aire frío y seco desde las capas altas a las capas medias. Porque viendo los mapas del CIMSS, está claro que SAL no es.
Está claro que si está temporada no está siendo explosiva es por culpa del aire seco, verdadero handicap este año... ¿Qué factores harán que esté más o menos presente a lo largo de una temporada? ??? ??? ??? Se supone que una parte del aire seco es el que va asociado al SAL. Pero también aire seco de origen estratosférico, que quizá pueda colarse en la troposfera debido a las turbulencias que generan las borrascas, sea cual sea el nivel que ocupen (borrascas que ocupen todo el perfil troposférico, o sólo las que ocupan parcelas superiores, como las DANAs). Si hay una gran actividad ciclónica extratropical en una cuenca, a lo mejor hay más aire seco de origen estratosférico dando por saco... ¿Cómo lo ves?Pues esa pregunta me la he hecho yo esta mañana, y me han contestado que es debido a las altas presiones que dominan desde hace dos semanas el Atlántico Central, supongo que por un efecto de subsidencia que hace que descienda aire frío y seco desde las capas altas a las capas medias. Porque viendo los mapas del CIMSS, está claro que SAL no es.
Claro que tu explicación de las DANASs también suena razonable... porque una DANA arrastraría aire seco y frío a capas más bajas, ¿no? pero no sé si provocaría aire seco en una extensión tan enorme como la que ha ocupado en el Atlántico Central en las últimas semanas... no sé, a ver si alguien nos aclara esto, tengo muchas dudas.
000
WTNT41 KNHC 111449
TCDAT1
TROPICAL STORM IGOR DISCUSSION NUMBER 13
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL112010
1100 AM AST SAT SEP 11 2010
ALTHOUGH THE CONVECTIVE CLOUD TOPS HAVE WARMED...VISIBLE SATELLITE
IMAGES SHOW A BANDING EYE PRESENTATION WITH IGOR. WHILE THE
WEAKENING OF THE CONVECTION HAS LED TO A DECREASE IN DVORAK
T-NUMBERS...IT IS PREMATURE TO LOWER THE INTENSITY AND 60 KT WILL BE
KEPT FOR THIS ADVISORY.
ALTHOUGH EASTERLY SHEAR REMAINS PRESENT...IT HAS DECREASED SINCE
YESTERDAY AND IS FORECAST TO FURTHER DIMINISH DURING THE NEXT DAY
OR SO. AROUND THAT TIME...THE CYCLONE IS FORECAST TO MOVE OVER
WATERS WARMER THAN 28C. THESE CONDITIONS SHOULD PROMOTE GRADUAL
STRENGTHENING IN THE SHORT-TERM...WITH THE POTENTIAL FOR A MORE
SIGNIFICANT INTENSIFICATION IN A COUPLE OF DAYS. INTERESTINGLY...
WHILE THE STATISTICAL MODELS MAKE IGOR A CATEGORY 4 HURRICANE...THE
GFDL AND HWRF MODELS SHOW SOME WEAKENING WITH IGOR BEFORE
RESTRENGTHENING THE CYCLONE IN A FEW DAYS. AT THIS POINT...I AM
INCLINED TO LEAN ON THE STATISTICAL MODELS AT THE END OF THE
PERIOD GIVEN THE FORECAST UPPER-LEVEL WIND PATTERN...AND HAVE RAISED
THE WINDS FOR THAT TIME.
MICROWAVE AND VISIBLE IMAGES SUGGEST THE SYSTEM HAS SLOWED A BIT AND
IS MOVING 275/17. THE GLOBAL MODELS ARE IN GOOD AGREEMENT ON A
WESTWARD TRACK OF IGOR FOR THE NEXT FEW DAYS AS RIDGING REMAINS
ENTRENCHED TO THE NORTH. IN ABOUT 3 DAYS...THE WESTERN PART OF THE
RIDGE WEAKENS DUE TO A LARGE MID-LATITUDE TROUGH. THIS PATTERN
SHOULD ALLOW IGOR TO GAIN A BIT MORE LATITUDE AND SLOW DOWN. WHILE
THE MODELS ARE IN GENERAL AGREEMENT WITH THIS SCENARIO...THERE ARE
SOME LARGE SPEED DIFFERENCES...AS THE ECMWF IS SIGNIFICANTLY SLOWER
THAN MOST OF THE OTHER GUIDANCE. THE NHC FORECAST IS CLOSE TO THE
PREVIOUS ONE...ON THE SOUTHERN AND WESTERN SIDES OF THE GUIDANCE
ENVELOPE...ATTEMPTING TO ACCOUNT FOR THE MODEL TENDENCIES OF BEING
TOO SLOW AND POLEWARD WITH LOW-LATITUDE SYSTEMS.
FORECAST POSITIONS AND MAX WINDS
INITIAL 11/1500Z 17.4N 39.5W 60 KT
12HR VT 12/0000Z 17.5N 42.0W 65 KT
24HR VT 12/1200Z 17.6N 44.9W 70 KT
36HR VT 13/0000Z 17.7N 47.5W 80 KT
48HR VT 13/1200Z 17.7N 49.7W 90 KT
72HR VT 14/1200Z 18.0N 53.5W 105 KT
96HR VT 15/1200Z 19.5N 56.5W 110 KT
120HR VT 16/1200Z 21.0N 59.5W 110 KT
$$
FORECASTER BLAKE
000
WTNT41 KNHC 121823
TCDAT1
HURRICANE IGOR SPECIAL DISCUSSION NUMBER 18
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL112010
130 PM AST SUN SEP 12 2010
SATELLITE IMAGERY AND THE UW-CIMSS ADVANCED DVORAK TECHNIQUE
INDICATE THAT IGOR HAS CONTINUED TO RAPIDLY INTENSIFY AND IS NOW A
CATEGORY FOUR HURRICANE. THE VISIBLE AND BD-CURVE INFRARED
ENHANCEMENT PICTURES REVEAL A CLEAR 20 NMI DIAMETER EYE WITH A
SURROUNDING INTENSE INNER CORE RING OF -80 DEGREE CELSIUS CLOUD TOP
TEMPERATURES. THE OFFICIAL INTENSITY FORECAST HAS BEEN MODIFIED TO
INDICATE SOME ADDITIONAL INTENSIFICATION DURING THE NEXT 3 DAYS AND
THEN SHOWS A SLIGHT DECREASE AT DAYS 4 AND 5. ALSO...FLUCTUATIONS
IN STRENGTH DUE TO EYEWALL REPLACEMENT CYCLES ARE POSSIBLE...BUT
THERE IS LITTLE SKILL IN FORECASTING THE TIMING OF THESE CYCLES.
THE WIND RADII FORECAST HAS ALSO BEEN ADJUSTED TO ACCOUNT FOR THE
INCREASE IN THE INTENSITY. THE OFFICIAL NHC TRACK FORECAST REMAINS
UNCHANGED FROM THE PREVIOUS ADVISORY.
FORECAST POSITIONS AND MAX WINDS
INITIAL 12/1830Z 17.7N 46.1W 115 KT
12HR VT 13/0000Z 17.8N 47.5W 125 KT
24HR VT 13/1200Z 18.0N 49.8W 125 KT
36HR VT 14/0000Z 18.4N 51.8W 125 KT
48HR VT 14/1200Z 19.0N 53.6W 130 KT
72HR VT 15/1200Z 20.7N 56.7W 130 KT
96HR VT 16/1200Z 22.6N 59.6W 125 KT
120HR VT 17/1200Z 24.5N 62.5W 125 KT
$$
FORECASTER ROBERTS/BRENNAN
000
WTNT41 KNHC 122038
TCDAT1
HURRICANE IGOR DISCUSSION NUMBER 19
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL112010
500 PM AST SUN SEP 12 2010
IGOR CONTINUES TO INTENSIFY AT A RAPID PACE. DVORAK INTENSITY
ESTIMATES AND THE UW-CIMSS ADT HAVE INCREASED FURTHER...AND THE
INITIAL INTENSITY IS ADJUSTED SLIGHTLY UPWARD TO 120 KT BASED ON A
COMPROMISE OF THESE DATA AND THE LATEST SATCON INTENSITY ESTIMATE.
THE OFFICIAL INTENSITY FORECAST HAS ALSO BEEN ADJUSTED TO SHOW SOME
FURTHER STRENGTHENING AND A PEAK INTENSITY AT DAY 3 OF 135
KT...SIMILAR TO SHIPS MODEL. FOR THE REMAINDER OF THE PERIOD...THE
OFFICIAL FORECAST CALLS FOR SOME GRADUAL WEAKENING AND IS BASED
PRIMARILY ON THE ICON CONSENSUS MODEL. IT IS WORTH NOTING THAT
FLUCTUATIONS IN STRENGTH DUE TO EYEWALL REPLACEMENT CYCLES ARE
POSSIBLE...HOWEVER...THERE IS LITTLE SKILL IN FORECASTING THE
TIMING OF THESE CYCLES.
THE INITIAL MOTION ESTIMATE REMAINS 270/12. THE TRACK FORECAST
PHILOSOPHY REMAINS UNCHANGED FOR THIS ADVISORY...HOWEVER THERE IS
STILL CONSIDERABLE DYNAMICAL MODEL SPREAD AFTER 36 HOURS. THE
HWRF...UKMET AND ECMWF REMAIN TO THE LEFT OF THE CONSENSUS AND ARE
SLIGHTLY SLOWER...WHILE THE OTHER REGIONAL AND GLOBAL MODELS
SUGGEST A MORE PRONOUNCED WEAKNESS WITH TIME IN THE MID- TO
UPPER-LEVEL RIDGE. THE NHC TRACK FORECAST IS NUDGED TO THE RIGHT OF
THE PREVIOUS FORECAST AFTER DAY 3...CLOSER TO THE TVCN CONSENSUS
MODEL...BUT STILL TO THE LEFT OUT OF RESPECT TO THE RELIABLE ECMWF
MODEL.
FORECAST POSITIONS AND MAX WINDS
INITIAL 12/2100Z 17.7N 46.9W 120 KT
12HR VT 13/0600Z 17.8N 48.7W 125 KT
24HR VT 13/1800Z 18.1N 50.8W 125 KT
36HR VT 14/0600Z 18.7N 52.6W 130 KT
48HR VT 14/1800Z 19.4N 54.3W 130 KT
72HR VT 15/1800Z 21.3N 57.1W 135 KT
96HR VT 16/1800Z 23.5N 60.0W 125 KT
120HR VT 17/1800Z 25.8N 62.9W 120 KT
$$
FORECASTER ROBERTS/BRENNAN
12 September 2010By NASA.
IGOR BECOMIMG A DANGEROUS HURRICANE Tropical storm IGOR was upgraded by the National Hurricane Center (NHC) in Miami, Florida to a hurricane on Sunday 12 September 2010 at 0300 UTC and has been predicted to strengthen to a major hurricane within a few days. The TRMM satellite passed almost directly above hurricane IGOR a few hours later on Sunday 12 September 2010 at 0504UTC ( 1:04 AM EDT). The TRMM Precipitation Radar (PR) and TRMM Microwave Imager (TMI) data collected with this orbit revealed that IGOR had a well defined circular eye containing bands of heavy rainfall.
Respecto a súbitas intensificaciones de huracanes, recuerdo a bote pronto la de Bertha en 2.008:
http://www.cazatormentas.net/index.php/Noticias-sobre-huracanes-ciclones-y-tifones./Gran-Huracan-BERTHA-establece-nuevos-records.html (http://www.cazatormentas.net/index.php/Noticias-sobre-huracanes-ciclones-y-tifones./Gran-Huracan-BERTHA-establece-nuevos-records.html)
000
WTNT41 KNHC 130248
TCDAT1
HURRICANE IGOR DISCUSSION NUMBER 20
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL112010
1100 PM AST SUN SEP 12 2010
IGOR HAS CONTINUED TO INTENSIFY WITH VERY COLD CLOUD TOPS...LOWER
THAN -70C...WRAPPING AROUND THE SLOWLY-SHRINKING EYE DURING THE
PAST SEVERAL HOURS. ALTHOUGH THE TOPS HAVE RECENTLY WARMED A
LITTLE OVER THE SOUTHWEST QUADRANT...SUBJECTIVE DVORAK ESTIMATES
FROM TAFB AND SAB ARE T6.5/127 KT AND OBJECTIVE ESTIMATES FROM THE
ADT AND HIE ALGORITHMS ARE T6.6/130 KT AND T6.9/137 KT...
RESPECTIVELY. AS A COMPROMISE...THE INITIAL INTENSITY IS SET AT
130 KT. AN EXPERIMENTAL PRODUCT FROM UW-CIMSS RUN AT NHC INDICATES
THAT THERE IS A 42 PERCENT CHANCE OF SECONDARY EYEWALL FORMATION
WITHIN THE NEXT 12 HOURS...AND A 90 PERCENT CHANCE WITHIN 24 HOURS.
THE PERIOD OF RAPID INTENSIFICATION IS LIKELY TO END SOON...BUT THE
OFFICIAL FORECAST FOLLOWS THE SHIPS/LGEM MODELS BY SHOWING IGOR
REACHING THE THRESHOLD OF CATEGORY 5 STRENGTH BEFORE THAT HAPPENS.
SOME WEAKENING IS THEN INDICATED AFTER EYEWALL REPLACEMENT
OCCURS...BUT IGOR IS EXPECTED TO REMAIN A POWERFUL HURRICANE FOR
SEVERAL DAYS. AS IS ALWAYS THE CASE WITH STRONG HURRICANES LIKE
IGOR...FLUCTUATIONS IN INTENSITY ARE LIKELY BUT ARE ALSO DIFFICULT
TO FORECAST.
THE MEAN MOTION IS 270/11...BUT IGOR HAS BEEN WOBBLING A LITTLE TO
THE SOUTH OF THAT VECTOR. IGOR IS MOVING INTO AN ENVIRONMENT WHERE
THE STEERING FLOW IS BECOMING INCREASINGLY DICTATED BY A LARGE
LONGWAVE TROUGH OVER THE WESTERN ATLANTIC...AND THE HURRICANE IS
EXPECTED TO RESPOND BY TURNING TOWARD THE WEST-NORTHWEST WITHIN THE
NEXT 24-48 HOURS. SOME OF THE GLOBAL MODELS INDICATE THAT THE
TROUGH COULD FLATTEN A LITTLE BY DAY 3 AND ALLOW THE SUBTROPICAL
RIDGE TO BUILD WESTWARD...BUT AT THIS TIME THERE IS TOO MUCH
DISAGREEMENT TO INDICATE A WESTWARD TURN IN THE FORECAST. THE
TRACK GUIDANCE HAS SHIFTED A LITTLE TO THE NORTH...BUT THE NEW
OFFICIAL FORECAST STILL LIES ON THE SOUTHERN SIDE OF THE GUIDANCE
ENVELOPE UNTIL IT BECOMES CLEAR THAT IGOR IS READY TO TURN. THIS
SOLUTION ALSO GIVES CREDENCE TO THE MORE SOUTHERN ECMWF AND UKMET
MODELS.
FORECAST POSITIONS AND MAX WINDS
INITIAL 13/0300Z 17.6N 47.8W 130 KT
12HR VT 13/1200Z 17.8N 49.5W 140 KT
24HR VT 14/0000Z 18.2N 51.3W 135 KT
36HR VT 14/1200Z 18.9N 53.0W 130 KT
48HR VT 15/0000Z 19.8N 54.6W 125 KT
72HR VT 16/0000Z 22.0N 57.5W 125 KT
96HR VT 17/0000Z 24.0N 60.0W 120 KT
120HR VT 18/0000Z 27.0N 63.0W 110 KT
$$
FORECASTER BERG
000
WTNT41 KNHC 130835
TCDAT1
HURRICANE IGOR DISCUSSION NUMBER 21
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL112010
500 AM AST MON SEP 13 2010
IGOR REMAINS A POWERFUL AND WELL ORGANIZED HURRICANE WITH A
SYMMETRIC EYEWALL...CLOUD TOPS COLDER THAN -70 C...A 15 N MI
CIRCULAR EYE...AND SPIRAL RAINBANDS. SATELLITE CLASSIFICATIONS
FROM ALL AGENCIES HAVE NOT CHANGED MUCH FROM 0000 UTC...AND
THEREFORE THE INITIAL INTENSITY IS HELD AT 130 KT FOR THIS
ADVISORY. AS IS COMMON FOR MAJOR HURRICANES IN FAVORABLE OCEANIC
AND ATMOSPHERIC ENVIRONMENTS...INTERNAL DYNAMICS WILL LIKELY GOVERN
THE INTENSITY CHANGE OF IGOR DURING THE NEXT DAY OR TWO. SINCE IT
APPEARS THAT AN EYEWALL REPLACEMENT CYCLE HAS NOT YET BEGUN...THE
OFFICIAL FORECAST WILL ALLOW FOR A LITTLE MORE STRENGTHENING TODAY.
THEREAFTER...A GRADUAL WEAKENING IS SHOWN FOLLOWING THE TREND IN
THE INTENSITY GUIDANCE. IGOR IS FORECAST TO MOVE INTO AN AREA OF
STRONGER SHEAR BY THE END OF THE PERIOD...WHICH SHOULD CAUSE A
LITTLE MORE WEAKENING.
THE HURRICANE CONTINUES TO MOVE WESTWARD AT 11 KT...AND IS ON THE
PREVIOUS FORECAST TRACK. IGOR IS EXPECTED TO TURN WEST-
NORTHWESTWARD IN ABOUT 24 HOURS AND THEN NORTHWESTWARD IN A
COUPLE OF DAYS AS IT APPROACHES A BROAD TROUGH OVER THE CENTRAL AND
WESTERN ATLANTIC. ALTHOUGH MOST OF THE GLOBAL MODELS SHOW THE
TROUGH FLATTENING IN 3 TO 4 DAYS...THERE ARE DISAGREEMENTS IN HOW
MUCH...IF ANY...SUBTROPICAL RIDGING BUILDS IN THE WAKE OF THE
TROUGH. THE ECMWF AND UKMET MODELS CONTINUE TO BUILD MORE RIDGING
NORTH OF IGOR...RESULTING IN A TRACK FARTHER WEST THAN THE OTHER
MODELS. OVERALL...THE MODEL GUIDANCE HAS SHIFTED SLIGHTLY TO THE
RIGHT FROM THE LAST CYCLE AND THE OFFICIAL FORECAST IS NUDGED IN
THAT DIRECTION...BUT REMAINS ON THE SOUTH SIDE OF THE GUIDANCE
ENVELOPE.
FORECAST POSITIONS AND MAX WINDS
INITIAL 13/0900Z 17.7N 48.8W 130 KT
12HR VT 13/1800Z 17.9N 50.2W 140 KT
24HR VT 14/0600Z 18.5N 51.8W 135 KT
36HR VT 14/1800Z 19.3N 53.4W 130 KT
48HR VT 15/0600Z 20.4N 54.9W 125 KT
72HR VT 16/0600Z 22.5N 57.7W 120 KT
96HR VT 17/0600Z 25.0N 60.0W 115 KT
120HR VT 18/0600Z 28.0N 63.0W 105 KT
$$
FORECASTER CANGIALOSI
Aún no gira hacia el WNW, se espera que el giro comience bien por la tarde o a inicios de la noche, ven ustedes alguna probabilidad de que no gire al WNW?
000
WTNT41 KNHC 132038
TCDAT1
HURRICANE IGOR DISCUSSION NUMBER 23
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL112010
500 PM AST MON SEP 13 2010
THE STRUCTURE OF IGOR HAS CHANGED LITTLE OVER THE PAST FEW HOURS.
THE EYE REMAINS VERY DISTINCT IN IR AND VISIBLE IMAGERY...AND
ALTHOUGH THE TOPS SURROUNDING THE EYE HAVE WARMED A BIT...DVORAK
CLASSIFICATIONS STILL SUPPORT AN INTENSITY OF 130 KT. IGOR WILL
REMAIN IN A FAVORABLE ENVIRONMENT FOR MAINTAINING ITS CURRENT
INTENSITY FOR THE NEXT COUPLE OF DAYS...AND THE OFFICIAL FORECAST
DOES NOT SHOW ANY WEAKENING UNTIL AFTER 48 HOURS. WHILE A 1640 UTC
AMSR-E PASS DOES NOT SHOW ANY EVIDENCE OF A SECONDARY EYEWALL
YET...IT IS POSSIBLE THAT AN EYEWALL REPLACEMENT CYCLE WILL OCCUR
IN THE FIRST COUPLE OF DAYS...WHICH COULD RESULT IN SOME INTENSITY
FLUCTUATIONS NOT REPRESENTED IN THE OFFICIAL FORECAST. BEYOND 36
HOURS...ALL OF THE INTENSITY GUIDANCE SUGGEST THAT SLOW WEAKENING
SHOULD BEGIN...ALTHOUGH THERE ARE NO OVERLY NEGATIVE FACTORS UNTIL
THE VERY END OF THE PERIOD WHEN THE VERTICAL SHEAR MAY INCREASE.
THE OFFICIAL FORECAST SHOWS A GRADUAL WEAKENING AT DAYS 3 THROUGH 5
BUT IS HIGHER THAN MOST OF THE GUIDANCE THROUGH THE PERIOD.
THE INITIAL MOTION IS STILL DUE WEST...270 DEGREES...AT 9 KNOTS.
ALL OF THE GUIDANCE...EXCEPT THE UKMET...INSISTS ON A TURN TOWARD
THE WEST-NORTHWEST IN THE NEXT 12 HOURS AS IGOR BEGINS TO MOVE INTO
A LARGE WEAKNESS IN THE SUBTROPICAL RIDGE. HOWEVER...DUE TO THE
INITIAL POSITION AND MOTION...THE OFFICIAL FORECAST HAS AGAIN BEEN
ADJUSTED A LITTLE TO THE LEFT OF THE PREVIOUS ADVISORY THROUGH 48
HOURS. BEYOND THAT TIME...THERE IS STILL SOME SPREAD IN THE TRACK
GUIDANCE. THE ECMWF AND UKMET STILL SHOW A STRONGER RIDGE NORTH OF
IGOR THROUGH MUCH OF THE PERIOD...TAKING THE CYCLONE FARTHER WEST
THAN THE REST OF THE GUIDANCE. THE GFS AND GFDL CONTINUE TO SHOW
THE LEAST RIDGING AND TURN IGOR NORTH-NORTHWESTWARD AT THE END OF
THE PERIOD AHEAD OF A MID-LATITUDE TROUGH. WHILE CONFIDENCE IN THE
TRACK FORECAST LATE IN THE PERIOD REMAINS LOW...THE GUIDANCE SHOWS
A LITTLE LESS SPREAD NOW THAN EARLIER TODAY. THE NEW OFFICIAL
FORECAST SHOWS A NORTHWESTWARD MOTION AT DAYS 3 THROUGH 5...AND IS
SIMILAR TO THE PREVIOUS FORECAST. THIS ENDS UP BEING VERY CLOSE TO
THE TVCN MULTI-MODEL CONSENSUS AND A BLEND OF THE GFS AND ECMWF
MODELS.
LARGE SWELLS FROM IGOR WILL BEGIN AFFECTING THE LEEWARD ISLANDS
TOMORROW AND REACH PUERTO RICO AND THE VIRGIN ISLANDS BY WEDNESDAY.
FORECAST POSITIONS AND MAX WINDS
INITIAL 13/2100Z 17.7N 50.5W 130 KT
12HR VT 14/0600Z 18.1N 51.7W 130 KT
24HR VT 14/1800Z 18.9N 53.2W 130 KT
36HR VT 15/0600Z 20.0N 54.7W 130 KT
48HR VT 15/1800Z 21.1N 56.1W 130 KT
72HR VT 16/1800Z 23.5N 58.5W 120 KT
96HR VT 17/1800Z 26.5N 61.5W 110 KT
120HR VT 18/1800Z 30.0N 64.0W 105 KT
$$
FORECASTER BRENNAN
000
WTNT41 KNHC 140246
TCDAT1
HURRICANE IGOR DISCUSSION NUMBER 24
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL112010
1100 PM AST MON SEP 13 2010
MICROWAVE AND GEOSTATIONARY SATELLITE IMAGERY SUGGESTS THAT AN
EYEWALL REPLACEMENT CYCLE MAY HAVE BEGUN. TRMM...WINDSAT...AND
SSMIS PASSES FROM ABOUT 5-6 HOURS AGO ALL INDICATED THAT A
SECONDARY EYEWALL WAS BEGINNING TO FORM...AND MORE RECENTLY
CONVECTIVE TOPS AROUND THE EYE HAVE BEEN WARMING. SUBJECTIVE
DVORAK FINAL-T ESTIMATES HAD FALLEN TO T6.0 TAFB AND SAB AT 0000
UTC...AND THE LATEST OBJECTIVE ADT ESTIMATE IS T6.0/6.4. BASED ON
THESE DATA...THE INITIAL INTENSITY IS LOWERED TO 120 KT. FOLLOWING
A CONSENSUS OF THE INTENSITY GUIDANCE...THE OFFICIAL FORECAST KEEPS
IGOR AT THIS INTENSITY FOR THE NEXT 24 HOURS OR SO...BUT IT IS
POSSIBLE THAT ADDITIONAL WEAKENING COULD OCCUR WHILE THE EYEWALL
REPLACEMENT IS IN PROGRESS. SINCE IGOR IS STILL EXPECTED TO BE
OVER WARM OCEAN WATERS AND REMAIN IN A LOW SHEAR ENVIRONMENT...THE
FORECAST ALLOWS FOR THE POSSIBILITY OF SOME RE-STRENGTHENING
BETWEEN 36-48 HOURS...WHICH IS HINTED AT IN THE SHIPS OUTPUT.
WEAKENING IS THEN INDICATED DURING DAYS 3 THROUGH 5...BUT IT IS
CONSERVATIVE AND STILL LIES JUST ABOVE THE UPPER BOUND OF THE
GUIDANCE.
IGOR JUST WILL NOT BUDGE VERY MUCH TO THE NORTH AND IS MOVING 275
DEGREES AT 8 KT. THE UKMET MODEL HAS CAPTURED THIS MOTION WELL
OVER THE PAST COUPLE OF DAYS AND HAS CONSISTENTLY BEEN LOCATED ON
THE SOUTHERN EDGE OF THE GUIDANCE ENVELOPE. SINCE THERE IS STILL
NO CLEAR EVIDENCE OF THE BEGINNING OF A TURN...THE NHC FORECAST
TRACK LIES ALONG THE SOUTHERN PERIPHERY OF THE TRACK GUIDANCE FOR
THE FIRST 24 HOURS...ALTHOUGH STILL NOT AS FAR SOUTH AS THE UKMET.
A TURN TOWARD THE NORTHWEST IS EXPECTED BY 36 HOURS WHEN IGOR
SHOULD HAVE REACHED THE BREAK IN THE SUBTROPICAL RIDGE. THE SPREAD
IN THE MODELS FROM DAYS 3 THROUGH 5 HAS AGAIN TIGHTENED...AND THE
OFFICIAL FORECAST IS CHANGED LITTLE FROM THE PREVIOUS ONE. THIS
FORECAST ALSO LIES CLOSE TO A MULTI-MODEL CONSENSUS THAT EXCLUDES
THE GFDN...WHICH HAS BEEN FASTER THAN THE OTHER GUIDANCE FOR
SEVERAL CYCLES.
LARGE SWELLS FROM IGOR WILL BEGIN AFFECTING THE LEEWARD ISLANDS
TOMORROW AND REACH PUERTO RICO AND THE VIRGIN ISLANDS BY WEDNESDAY.
FORECAST POSITIONS AND MAX WINDS
INITIAL 14/0300Z 17.7N 51.2W 120 KT
12HR VT 14/1200Z 18.0N 52.3W 120 KT
24HR VT 15/0000Z 18.8N 53.7W 120 KT
36HR VT 15/1200Z 19.9N 55.2W 125 KT
48HR VT 16/0000Z 21.1N 56.6W 125 KT
72HR VT 17/0000Z 24.0N 59.5W 115 KT
96HR VT 18/0000Z 27.0N 62.5W 105 KT
120HR VT 19/0000Z 30.5N 64.5W 95 KT
$$
FORECASTER BERG
SUMMARY OF 1100 PM AST...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...19.0N 53.9W
ABOUT 605 MI...975 KM E OF THE NORTHERN LEEWARD ISLANDS
ABOUT 1140 MI...1835 KM SE OF BERMUDA
MAXIMUM SUSTAINED WINDS...155 MPH...250 KM/HR
PRESENT MOVEMENT...WNW OR 295 DEGREES AT 9 MPH...15 KM/HR
MINIMUM CENTRAL PRESSURE...925 MB...27.32 INCHES
Ese virage de igor va a librar de una tragedia el caribe y el sur y este de estados unidos, por que igor es un katrina dos en potencia.
000
WTNT41 KNHC 160855
TCDAT1
HURRICANE IGOR DISCUSSION NUMBER 33
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL112010
500 AM AST THU SEP 16 2010
MICROWAVE AND INFRARED SATELLITE IMAGERY SUGGEST THAT THE EYEWALL
REPLACEMENT WITH IGOR IS COMPLETE. THE NEW EYEWALL APPEARS TO BE
CONSOLIDATING AT A RADIUS OF ABOUT 30-35 N MI AND IS PRODUCING
RATHER DEEP CONVECTION...SUGGESTING THE INTENSITY IS INCREASING
AGAIN. A BLEND OF THE SATELLITE ESTIMATES GIVES AN INITIAL
INTENSITY OF 125 KT.
A LARGE-SCALE ENVIRONMENT OF LIGHT SHEAR AND WARM WATER IS FAVORABLE
FOR THE MAINTENANCE OF AN EXTREMELY DANGEROUS HURRICANE FOR THE
NEXT FEW DAYS. THE EXACT INTENSITY OF IGOR WILL BE PRIMARILY
DICTATED BY EYEWALL CYCLES...WHICH ARE WELL BEYOND OUR FORECAST
ABILITIES. THE MAJORITY OF THE MODEL GUIDANCE INDICATES THAT SLOW
WEAKENING IS THE MOST LIKELY SOLUTION...AND THE NHC FORECAST REFLECT
THIS. HOWEVER...IT IS MORE IMPORTANT TO RECOGNIZE THAT ALL OF THE
GUIDANCE...AND THE NHC FORECAST...KEEPS IGOR AS A LARGE AND
DANGEROUS HURRICANE FOR THE NEXT SEVERAL DAYS.
THE INITIAL MOTION IS AN UNSTEADY 300/6. IGOR IS EXPECTED TO MOVE
SLOWLY AROUND THE WESTERN PERIPHERY OF A SUBTROPICAL RIDGE OVER THE
CENTRAL ATLANTIC. WEAK TROUGHING ALONG ABOUT 70W SHOULD RECURVE
THE CYCLONE IN 3 OR 4 DAYS. THE MAIN DIFFERENCE IN THE MODELS IS
HOW QUICKLY IGOR ACCELERATES TO THE NORTHEAST IN THE MID-LATITUDES.
SINCE THE TROUGHING OVER THE WESTERN ATLANTIC IS RATHER FLAT...
THERE HAS BEEN A TREND IN THE MODELS TO SHOW WEAKER FLOW NEAR
IGOR...AND CONSEQUENTLY DELAY THE INCREASE IN FORWARD SPEED. THE
OFFICIAL FORECAST IS A BIT SLOWER THAN THE PREVIOUS ONE...
ESPECIALLY AT THE END OF THE PERIOD. WITH REGARDS TO HOW CLOSE
IGOR COMES TO BERMUDA...THE ECMWF IS NOW THE MOST EASTERN MODEL
AFTER BEING THE WESTERNMOST YESTERDAY. THIS APPEARS TO BE DUE TO
THAT MODEL SHOWING A SLIGHTLY WEAKER RIDGE TODAY...WHICH ALLOWS
IGOR TO GAIN A LITTLE MORE LATITUDE EARLY ON AND EVENTUALLY PASS A
LITTLE FARTHER EAST OF BERMUDA. HOWEVER...ALL OF THE GUIDANCE IS
WELL CLUSTERED ON A TRACK CLOSE TO THAT ISLAND...AND LITTLE CHANGE
HAS BEEN MADE TO THE OFFICIAL TRACK NEAR BERMUDA. SINCE THIS IS
SUCH A LARGE HURRICANE...SIGNIFICANT IMPACTS ARE EXPECTED ON
BERMUDA...BUT IT IS TOO EARLY TO TELL HOW CLOSE THE CORE OF THE
HURRICANE...AND THE STRONGEST WINDS...WILL COME TO THAT ISLAND.
SO FAR...NOAA BUOY 41044 HAS REPORTED A PEAK 1-MINUTE WIND OF 45
KT...GUSTING TO 56 KT...ALONG WITH A MINIMUM PRESSURE OF 995
MB...AND A SIGNIFICANT WAVE HEIGHT OF 29 FT. HOWEVER...THE WORST
IS YET TO COME FOR THAT STATION...AS IGOR WILL MOVE VERY CLOSE TO
THE BUOY TONIGHT.
FORECAST POSITIONS AND MAX WINDS
INITIAL 16/0900Z 20.5N 56.8W 125 KT
12HR VT 16/1800Z 21.1N 57.8W 125 KT
24HR VT 17/0600Z 22.0N 59.4W 125 KT
36HR VT 17/1800Z 23.2N 61.1W 120 KT
48HR VT 18/0600Z 24.7N 62.7W 120 KT
72HR VT 19/0600Z 28.0N 65.0W 110 KT
96HR VT 20/0600Z 32.5N 64.5W 95 KT
120HR VT 21/0600Z 37.5N 59.0W 80 KT
$$
FORECASTER BLAKE
Continua en rota direca hasta las Bermudas ?
Continua en rota direca hasta las Bermudas ?
000
WTNT41 KNHC 180837
TCDAT1
HURRICANE IGOR DISCUSSION NUMBER 41
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL112010
500 AM AST SAT SEP 18 2010
DATA FROM THE HURRICANE HUNTER AIRCRAFT INDICATE THAT WHILE THE
CENTRAL PRESSURE OF IGOR HAD FALLEN TO 939 MB...THE WINDS AT FLIGHT
LEVEL WERE NOT EFFICIENTLY MIXING DOWN TO THE SURFACE. THE INITIAL
INTENSITY IS HELD AT 95 KT BASED ON A BLEND OF THE 115 KT FLIGHT-
LEVEL WIND MAXIMUM AND A MAXIMUM WIND OF 77 KT FROM THE SFMR. THE
OUTFLOW IS WELL ESTABLISHED...PARTICULARLY TO THE NORTH OF THE
CENTER...AND THE ENVIRONMENTAL CONDITIONS APPEAR FAVORABLE FOR A
LITTLE MORE STRENGTHENING OVER THE NEXT DAY OR SO BEFORE THE SHEAR
INCREASES. THE OFFICIAL FORECAST SHOWS A PEAK AT 105 KT IN 24
HOURS AND THEN A SLOW WEAKENING THROUGH 48 HOURS. REGARDLESS OF THE
DETAILS OF THE INTENSITY FORECAST...IGOR WILL BE A LARGE AND
DANGEROUS HURRICANE AS IT APPROACHES BERMUDA ON SUNDAY. WEAKENING
IS EXPECTED TO CONTINUE BEYOND 48 HOURS...AS IGOR MOVES OVER COOLER
WATERS AND THE SHEAR INCREASES FURTHER. ONCE IGOR COMPLETES
EXTRATROPICAL TRANSITION...IT WILL BE A LARGE AND POWERFUL CYCLONE
OVER THE NORTH ATLANTIC.
AFTER A SHORT TERM WOBBLE TOWARD THE WEST-NORTHWEST...THE LONG-TERM
INITIAL MOTION ESTIMATE IS 310/11. IGOR IS SITUATED SOUTH OF A
MID-LEVEL RIDGE EXTENDING ALONG 35N...AND THIS RIDGE IS FORECAST BY
ALL OF THE MODELS TO WEAKEN AS A SHORTWAVE TROUGH PROGRESSES EAST
OFF THE U.S. EAST COAST IN THE NEXT DAY OR SO. IGOR WILL TURN
NORTHWARD INTO THE WEAKNESS ALONG 65W ON SUNDAY AND PASS VERY NEAR
BERMUDA BEFORE TURNING NORTHEASTWARD ON MONDAY AHEAD OF ANOTHER
SHORTWAVE TROUGH MOVING OFF THE COAST OF NORTH AMERICA. THE GLOBAL
MODELS SHOW THE RIDGE NORTH OF IGOR REMAINING A LITTLE STRONGER
THAN PREVIOUSLY FORECAST...AND AS A RESULT MOST OF THE GUIDANCE HAS
SHIFTED A LITTLE TO THE LEFT AND SLOWER THROUGH 48 HOURS. THE
OFFICIAL FORECAST HAS BEEN ADJUSTED IN THIS DIRECTION...BUT REMAINS
TO THE RIGHT OF MOST OF THE GUIDANCE AND A LITTLE FASTER THAN
THE CONSENSUS. BEYOND 48 HOURS...THE NEW NHC FORECAST IS LARGELY
AN UPDATE OF THE PREVIOUS PACKAGE...AND SHOWS IGOR ACCELERATING
TOWARD THE NORTHEAST AS IT BECOMES EXTRATROPICAL.
IGOR HAS A VERY LARGE WIND FIELD...WITH A RADIUS OF MAXIMUM WINDS OF
AROUND 45 NAUTICAL MILES AND HURRICANE FORCE WINDS EXTENDING OUT UP
TO 90 NM FROM THE CENTER. CONDITIONS WILL BEGIN TO DETERIORATE ON
BERMUDA BY TONIGHT...WELL IN ADVANCE OF THE CENTER.
FORECAST POSITIONS AND MAX WINDS
INITIAL 18/0900Z 25.1N 62.8W 95 KT
12HR VT 18/1800Z 26.2N 64.1W 100 KT
24HR VT 19/0600Z 27.8N 65.1W 105 KT
36HR VT 19/1800Z 29.9N 65.3W 100 KT
48HR VT 20/0600Z 32.2N 64.7W 95 KT
72HR VT 21/0600Z 38.5N 58.5W 80 KT
96HR VT 22/0600Z 47.5N 46.5W 65 KT...POST-TROP/EXTRATROP
120HR VT 23/0600Z 51.5N 39.5W 55 KT...POST-TROP/EXTRATROP
$$
FORECASTER BRENNAN
000
WTNT41 KNHC 190853
TCDAT1
HURRICANE IGOR DISCUSSION NUMBER 45
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL112010
500 AM AST SUN SEP 19 2010
DATA FROM THE HURRICANE HUNTER AIRCRAFT AND SATELLITE IMAGERY
INDICATE THAT IGOR HAS CONTINUED TO SLOWLY WEAKEN. THE AIRCRAFT
DID NOT REPORT AN EYEWALL...AND SOME DRY AIR ALSO APPEARS TO BE
WORKING ITS WAY INTO THE CIRCULATION...PARTICULARLY OVER THE
WESTERN SEMICIRCLE. THE INITIAL INTENSITY IS LOWERED TO 75 KT
BASED ON A BLEND OF THE FLIGHT LEVEL MAXIMUM WIND OF 91 KT AND A
MAXIMUM SFMR READING OF 68 KT. WHILE THE STRONGEST WINDS HAVE
DECREASED...THE SFMR DATA SHOWS THAT THE WIND FIELD OF IGOR
CONTINUES TO BROADEN...AND THE 50-KT AND 64-KT WIND RADII HAVE BEEN
INCREASED. LITTLE CHANGE IN INTENSITY IS EXPECTED FOR THE NEXT
COUPLE OF DAYS...AND IGOR WILL BE A LARGE HURRICANE AS IT PASSES BY
BERMUDA IN THE NEXT 24 HOURS AND SUBJECTS THAT ISLAND TO A LONG
PERIOD OF STRONG WINDS...WITH TROPICAL STORM CONDITIONS LIKELY
LASTING AT LEAST 24 HOURS. BY 72 HOURS...IGOR WILL TRANSITION TO A
POWERFUL AND LARGE EXTRATROPICAL CYCLONE AND THEN SLOWLY WEAKEN
THROUGH THE END OF THE PERIOD.
THE INITIAL MOTION ESTIMATE IS 340/10. THE LATEST AIRCRAFT FIXES
WERE LOCATED A LITTLE TO THE WEST OF THE APPARENT CENTER IN
GEOSTATIONARY IMAGERY...AND ALSO A LITTLE TO THE LEFT OF THE
PREVIOUS FORECAST TRACK. THE OVERALL TRACK FORECAST REASONING
REMAINS UNCHANGED...AS IGOR WILL TURN NORTHWARD SOON AS IT MOVES
AROUND THE WESTERN PERIPHERY OF THE SUBTROPICAL RIDGE...AND THEN
ACCELERATE TOWARD THE NORTHEAST ON MONDAY AS IT RECURVES AHEAD
OF A MID-LATITUDE TROUGH MOVING OFF THE COAST OF NORTH AMERICA.
THROUGH 36 HOURS THE OFFICIAL FORECAST HAS BEEN ADJUSTED A LITTLE
TO THE LEFT OF THE PREVIOUS ONE TO ACCOUNT FOR THE INITIAL POSITION
AND LIES ALONG THE EASTERN EDGE OF THE TIGHTLY CLUSTERED GUIDANCE
ENVELOPE. THE SPREAD IN THE GUIDANCE INCREASES BEYOND 48 HOURS DUE
TO VARIATIONS IN THE DETAILS OF HOW IGOR INTERACTS WITH THE
MID-LATITUDE FLOW DURING AND AFTER EXTRATROPICAL TRANSITION. THE
OFFICIAL FORECAST HAS BEEN ADJUSTED NORTHWARD AT DAYS 3 AND 4 AND
IS IN BEST AGREEMENT WITH THE GFS MODEL. AT DAY 5 THE OFFICIAL
FORECAST SHOWS POST-TROPICAL IGOR SLOWING AND TURNING MORE NORTHWARD
...HOWEVER CONFIDENCE IS LOW IN THIS SCENARIO AS THE SPREAD IN THE
GUIDANCE IS VERY LARGE.
FORECAST POSITIONS AND MAX WINDS
INITIAL 19/0900Z 28.9N 65.3W 75 KT
12HR VT 19/1800Z 30.5N 65.5W 75 KT
24HR VT 20/0600Z 33.4N 64.9W 75 KT
36HR VT 20/1800Z 37.0N 62.5W 75 KT
48HR VT 21/0600Z 41.0N 57.5W 75 KT
72HR VT 22/0600Z 49.0N 47.0W 70 KT...POST-TROP/EXTRATROP
96HR VT 23/0600Z 53.0N 38.0W 45 KT...POST-TROP/EXTRATROP
120HR VT 24/0600Z 56.5N 36.5W 35 KT...POST-TROP/EXTRATROP
$$
FORECASTER BRENNAN