000WTNT42 KNHC 170834TCDAT2TROPICAL DEPRESSION BILL DISCUSSION NUMBER 6NWS NATIONAL HURRICANE CENTER MIAMI FL AL022015400 AM CDT WED JUN 17 2015While radar data show that Bill is maintaining a goodconvective banding structure, surface observations indicate thatthe cyclone has weakened to a tropical depression over centralTexas. The initial intensity is 30 kt, with these winds occurringin rainbands near and east of the center. The large-scale modelssuggest that only slow weakening will occur during the next 24-36hours, and Bill is likely to remain a tropical cyclone until thecenter moves into eastern Oklahoma on Thursday. After that, thecyclone is expected to degenerate to a remnant low, with the lowbeing absorbed by a frontal system over the eastern United Statesin about 96 hours.The initial motion is 360/11. Bill is expected to moved northwardfor the next 12-24 hours on the west side of the subtropical ridge.Subsequently, the cyclone should turn northeastward as it entersthe westerlies. The track model guidance is in good agreement withthis scenario, and the new forecast track lies close to the modelconsensus.The main hazard from Bill is expected to be heavy rainfall andflooding across portions of eastern Texas and eastern Oklahomaover the next day or two. Please see products from your localNational Weather Service office for more information on the floodthreat.This is the last advisory on Bill issued by the National HurricaneCenter. Future information on this system can be found in PublicAdvisories issued by the Weather Prediction Center beginning at 10AM CDT, under AWIPS header TCPAT2, WMO header WTNT32 KWNH, and onthe web at http://www.hpc.ncep.noaa.gov/tropical/.FORECAST POSITIONS AND MAX WINDSINIT 17/0900Z 31.0N 97.1W 30 KT 35 MPH...INLAND 12H 17/1800Z 32.6N 97.2W 30 KT 35 MPH...INLAND 24H 18/0600Z 34.3N 96.8W 25 KT 30 MPH...INLAND 36H 18/1800Z 35.5N 95.2W 25 KT 30 MPH...POST-TROP/INLAND 48H 19/0600Z 36.5N 93.6W 20 KT 25 MPH...POST-TROP/INLAND 72H 20/0600Z 38.5N 89.5W 20 KT 25 MPH...POST-TROP/INLAND 96H 21/0600Z...DISSIPATED$$Forecaster Beven
DISCUSSION AND 48-HOUR OUTLOOK------------------------------AT 400 AM CDT...0900 UTC...THE CENTER OF BILL WAS LOCATED NEARLATITUDE 37.8 NORTH...AND LONGITUDE 87.1 WEST. AFTER SPENDING MORETHAN THREE DAYS OVER LAND...TROPICAL DEPRESSION BILL CONTINUES TOMAINTAIN A WELL-DEFINED CYCLONIC CIRCULATION AS IT TRACKS WELLINLAND OVER SATURATED GROUNDS RESULTING FROM ANTECEDENT HEAVYRAINS. SATELLITE IMAGERY CONTINUES TO SHOW DECENT CONVECTIONAROUND THE CENTER OF BILL ALONG WITH A PROMINENT UPPER-LEVELOUTFLOW PATTERN TO THE NORTH. RADAR IMAGERY AND SURFACEOBSERVATIONS SHOW A BROAD AXIS OF LIGHT TO MODERATE RAINFALL AHEADOF THE CIRCULATION. MEANWHILE...TO THE NORTH OF BILL...ADEFORMATION ZONE HAS SET UP ACROSS SOUTHERN INDIANA. THIS SHIELDOF HEAVY RAINFALL HAS BEEN GENERALLY PIVOTING OVER THE SAMELOCATIONS THE PAST COUPLE OF HOURS. THE CENTRAL PRESSURE HASBECOME STEADY DURING THE PAST 6 HOURS AFTER A BRIEF DECREASE THISPAST AFTERNOON. RECENT PEAK WIND GUSTS HAVE BEEN IN THE 25 TO 30MPH RANGE...GENERALLY WITHIN THE SOUTHEASTERN SECTOR OF THECIRCULATION. BILL IS EXPECTED TO CONTINUE MOVINGEAST-NORTHEASTWARD UP THE OHIO VALLEY AND INTO THE CENTRALAPPALACHIANS BEFORE LOSING TROPICAL CHARACTERISTICS. THEREAFTER...BILL COULD BRIEFLY RESTRENGTHEN WHEN IT MOVES DOWNTHE LEE SIDE OF THE APPALACHIANS ON SUNDAY AS IT GRADUALLY BECOMESEXTRATROPICAL OVER THE NORTHERN MID-ATLANTIC AND SOUTHERN NEWENGLAND COAST.