Show Selection: |
#157077 (Received by flhurricane at: 10:58 AM 29.Oct.2007) TCDAT1 TROPICAL STORM NOEL DISCUSSION NUMBER 8 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL162007 1100 AM EDT MON OCT 29 2007 NOEL HAS BECOME LESS ORGANIZED AS IT INTERACTS WITH THE COMPLEX TERRAIN OF HISPANIOLA. A MID-LEVEL VORTICITY MAXIMUM EMERGED NORTH OF THE ISLAND A FEW HOURS AGO...AND VISIBLE IMAGERY SUGGESTS A LOW-LEVEL CENTER IS REFORMING ALONG THE NORTHWESTERN COAST OF HAITI. UNTIL THE NEXT AIR FORCE RECONNAISSANCE PLANE INVESTIGATES THE AREA THIS AFTERNOON...THE LOCATION...FORWARD MOTION...AND EVEN THE EXISTENCE OF A LOW-LEVEL CENTER REMAIN RATHER UNCERTAIN. OUR BEST ESTIMATE OF THE INITIAL MOTION IS NORTH-NORTHWESTWARD OR 335/10...WITH STEERING PROVIDED BY A LOW- TO MID-LEVEL RIDGE NORTH AND EAST OF THE CYCLONE. NEARLY ALL OF THE DYNAMICAL MODELS FORECAST A SURFACE LOW TO BECOME RE-ESTABLISHED SOMEWHERE OVER THE BAHAMAS DURING THE NEXT DAY OR SO...BUT THEY DO NOT AGREE ON THE VERTICAL EXTENT OF THE CIRCULATION. THE GFDL CONTINUES TO INSIST ON NOEL BECOMING A HURRICANE THAT WILL ACCELERATE QUICKLY NORTHWARD AND THEN NORTHEASTWARD. THE OTHER EXTREME IS THE ECMWF THAT DEPICTS A WEAK SURFACE LOW HANGING OUT NEAR CUBA FOR THE NEXT FIVE DAYS. THE REMAINING MODELS ARE IN BETWEEN...AND FORECAST A GENERAL NORTHWESTWARD MOTION WITH A DECREASE IN FORWARD SPEED DURING THE NEXT 48 HOURS. SOME OF THOSE MODELS...INCLUDING THE GFS...FORECAST LITTLE MOTION ON DAYS 3-5...WHILE THE NOGAPS SHOWS A NORTHEASTWARD ACCELERATION IN THAT TIME FRAME. THE NEW OFFICIAL TRACK FORECAST SHOWS A WEAKENING AND INCREASINGLY SHALLOW CYCLONE THAT SLOWLY RECURVES NORTHEASTWARD OVER THE BAHAMAS AFTER 48 HOURS...IN RESPONSE TO AN APPROACHING SHORT-WAVE TROUGH...SIMILAR TO THE HWRF SOLUTION AND A LITTLE SLOWER THAN THE PREVIOUS ADVISORY. ASSUMING THE CYCLONE REGAINS SUFFICIENT ORGANIZATION AFTER BEING DISRUPTED OVER HISPANIOLA...ATMOSPHERIC AND OCEAN CONDITIONS SHOULD PROVIDE NOEL WITH AN OPPORTUNITY TO STRENGTHEN A LITTLE DURING THE NEXT DAY OR TWO. THEREAFTER...WESTERLY WIND SHEAR SHOULD DRAMATICALLY INCREASE AND INDUCE A WEAKENING TREND. THE NEW OFFICIAL INTENSITY FORECAST IS ADJUSTED SLIGHTLY DOWNWARD COMPARED TO THE PREVIOUS ADVISORY...ESPECIALLY AFTER 48 HOURS. THIS FORECAST IS IN BEST AGREEMENT WITH THE LGEM AND HWRF GUIDANCE...AND BELOW THE SHIPS AND GFDL. FORECAST POSITIONS AND MAX WINDS INITIAL 29/1500Z 19.9N 73.0W 40 KT 12HR VT 30/0000Z 21.2N 73.7W 40 KT 24HR VT 30/1200Z 22.4N 74.4W 45 KT 36HR VT 31/0000Z 23.4N 75.4W 50 KT 48HR VT 31/1200Z 24.3N 76.7W 50 KT 72HR VT 01/1200Z 26.0N 76.5W 45 KT 96HR VT 02/1200Z 28.0N 75.0W 40 KT 120HR VT 03/1200Z 30.0N 72.5W 35 KT $$ FORECASTER KNABB/MAINELLI |