000 WTNT44 KNHC 100250 TCDAT4 TROPICAL STORM MARIA DISCUSSION NUMBER 14 NWS NATIONAL HURRICANE CENTER MIAMI FL AL142011 1100 PM AST FRI SEP 09 2011 MARIA HAS DEVELOPED A BAND OF STRONG CONVECTION OVER THE EASTERN SEMICIRCLE THIS EVENING...AND THERE HAS BEEN EVIDENCE OF CYCLONIC ROTATION IN RADAR DISPLAYS FROM BARBADOS...MARTINIQUE...AND GUADELOUPE. HOWEVER...THIS HAS NOT YET TRANSLATED INTO ANY INCREASED ORGANIZATION IN THE WIND FIELD ACCORDING TO DATA FROM AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT. THE AIRCRAFT DID NOT FIND STRONG WINDS DURING ITS MISSION...ALTHOUGH IT LIKELY DID NOT SAMPLE FAR ENOUGH FROM THE CENTER TO MEASURE THE STRONG WINDS IN THE NORTHEASTERN QUADRANT. THE INITIAL INTENSITY REMAINS 40 KT BASED ON RECENT OBSERVATIONS FROM A FRENCH BUOY EAST OF THE CENTER AND THE LIKELIHOOD OF STRONGER WINDS FARTHER NORTH. THE INITIAL MOTION IS A SOMEWHAT UNCERTAIN 295/12. MARIA IS ON THE SOUTH SIDE OF A LOW/MID-LEVEL SUBTROPICAL RIDGE...WHILE WATER VAPOR IMAGERY SHOWS AN UPPER-LEVEL LOW NORTH-NORTHWEST OF THE STORM NEAR 24N63W. THE DYNAMICAL MODELS FORECAST THE RIDGE TO PERSIST FOR 48 HOURS OR SO...THEN WEAKEN AS A DEEP-LAYER TROUGH MOVES EASTWARD ACROSS THE SOUTHEASTERN UNITED STATES INTO THE SOUTHWESTERN ATLANTIC. THE TRACK MODEL GUIDANCE IS IN EXCELLENT AGREEMENT THAT MARIA WILL MOVE GENERALLY NORTHWESTWARD FOR THE NEXT 48 HOURS... THEN GRADUALLY TURN NORTHWARD AND NORTH-NORTHEASTWARD IN RESPONSE TO THE APPROACHING TROUGH. FOR THE FIRST 72 HOURS...THE NEW FORECAST TRACK IS ALMOST IDENTICAL TO THE PREVIOUS TRACK AND IS DOWN THE MIDDLE OF THE GUIDANCE ENVELOPE. AFTER THAT...THE TRACK IS SHIFTED TO THE EAST OF THE PREVIOUS TRACK AND LIES A LITTLE TO THE LEFT OF...AND SLOWER...THAN THE MIDDLE OF THE GUIDANCE ENVELOPE. MARIA HAS DEVELOPED A GOOD UPPER-LEVEL OUTFLOW PATTERN...ALTHOUGH THERE MAY BE SOME RESIDUAL SHEAR UNDERCUTTING THE OUTFLOW. THE INTENSITY GUIDANCE UNANIMOUSLY FORECASTS THE STORM TO STRENGTHEN... ALTHOUGH THE CURRENT STATE OF DISORGANIZATION SUGGESTS THAT THE INITIAL STRENGTHENING SHOULD BE SLOW. THE NEW INTENSITY FORECAST CALLS FOR A SLOWER DEVELOPMENT RATE DURING THE FIRST 24-36 HOURS... THEN CATCHES UP WITH THE PREVIOUS FORECAST. LATER IN THE FORECAST PERIOD...MARIA IS FORECAST TO COME CLOSE TO THE AFOREMENTIONED UPPER-LEVEL LOW. THE DYNAMICAL MODELS HAVE A VARIETY OF SOLUTIONS FOR HOW THE TWO SYSTEMS WILL INTERACT...ALTHOUGH NONE OF THE GUIDANCE SHOW MARIA WEAKENING DUE TO THE INTERACTION. THE LATTER PART OF THE INTENSITY FORECAST IS IDENTICAL TO THE PREVIOUS FORECAST AND IS IN BEST AGREEMENT WITH A BLEND OF THE SHIPS AND LGEM MODELS. FORECAST POSITIONS AND MAX WINDS INIT 10/0300Z 15.1N 59.5W 40 KT 45 MPH 12H 10/1200Z 16.2N 61.5W 40 KT 45 MPH 24H 11/0000Z 17.8N 63.7W 45 KT 50 MPH 36H 11/1200Z 19.3N 65.8W 50 KT 60 MPH 48H 12/0000Z 20.8N 67.5W 60 KT 70 MPH 72H 13/0000Z 23.5N 70.0W 70 KT 80 MPH 96H 14/0000Z 27.5N 71.0W 80 KT 90 MPH 120H 15/0000Z 34.0N 69.0W 90 KT 105 MPH $$ FORECASTER BEVEN