000 WTNT41 KNHC 261446 TCDAT1 TROPICAL STORM ALEX DISCUSSION NUMBER 4 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 1000 AM CDT SAT JUN 26 2010 SATELLITE IMAGES SHOW THAT ALEX IS A LARGE CYCLONE WITH AN EXTENSIVE AREA OF CLOUDINESS...NUMEROUS SQUALLS IN RAINBANDS...AND A WELL ESTABLISHED UPPER-LEVEL OUTFLOW IN ALL QUADRANTS. HOWEVER... A RECENT MICROWAVE IMAGE REVEAL THAT ALEX STILL HAS A POORLY ORGANIZED INNER CORE. THE INITIAL INTENSITY OF 40 KNOTS IS BASED ON 3.0 AND 2.5 DVORAK T-NUMBERS FROM TABF AND SAB RESPECTIVELY...AND SURROUNDING SURFACE OBSERVATIONS. AN AIR FORCE PLANE IS SCHEDULED TO INVESTIGATE ALEX LATER TODAY AND WILL PROVIDE A BETTER ESTIMATE OF THE INTENSITY. ALTHOUGH ALEX IS EMBEDDED WITHIN A FAVORABLE ENVIRONMENT FOR INTENSIFICATION...THE STRENGTHENING WILL BE LIMITED BY THE EFFECT OF LAND PRIMARILY AS THE CYCLONE CROSSES THE YUCATAN PENINSULA WITHIN 12 TO 24 HOURS. ONCE IN THE GULF OF MEXICO...IN A COUPLE OF DAYS...THE CYCLONE COULD GAIN SOME STRENGTH AND ALEX IS FORECAST TO BECOME BECOME A HURRICANE BY THE END OF THE FORECAST PERIOD. THE OFFICIAL INTENSITY FORECAST IS A BLEND OF BOTH THE LGEM AND DECAY SHIPS MODELS. SINCE WE DO NOT HAVE A RELIABLE CENTER LOCATION...THE INITIAL MOTION CONTINUES TO BE UNCERTAIN. THE BEST ESTIMATE IS 290 DEGREES AT 9 KNOTS. ALEX IS CURRENTLY LOCATED ON THE SOUTH SIDE OF A SUBTROPICAL RIDGE EXTENDING WESTWARD FROM THE BAHAMAS ACROSS THE GULF OF MEXICO. THIS RIDGE WILL KEEP ALEX MOVING ON THE SAME GENERAL WEST-NORTHWEST TRACK FOR THE NEXT 24 TO 48 HOURS. THEREAFTER...THE RIDGE IS FORECAST TO WEAKEN AND ALEX SHOULD DECREASE ITS FORWARD SPEED. HOWEVER...MOST OF THE GLOBAL MODELS SHOW THAT THE RIDGE WILL BE STRONG ENOUGH TO KEEP THE CYCLONE ON A GENERAL WEST-NORTHWEST TRACK OVER THE SOUTHERN PORTION OF THE GULF OF MEXICO. IN FACT...THE GFDL/HWRF PAIR WHICH PREVIOUSLY MOVED ALEX ON A MORE NORTHERLY COMPONENT ACROSS THE GULF HAVE SHIFTED SOUTHWARD AND ARE NOW SHOWING A MORE WESTERWARD TRACK LIKE MOST OF THE GLOBAL MODELS. FORECAST POSITIONS AND MAX WINDS INITIAL 26/1500Z 17.3N 86.1W 40 KT 12HR VT 27/0000Z 17.7N 87.5W 50 KT 24HR VT 27/1200Z 19.0N 89.1W 30 KT...INLAND 36HR VT 28/0000Z 20.5N 91.0W 30 KT...OVER WATER 48HR VT 28/1200Z 22.0N 92.5W 40 KT 72HR VT 29/1200Z 23.0N 94.0W 55 KT 96HR VT 30/1200Z 23.5N 96.0W 65 KT 120HR VT 01/1200Z 24.0N 98.5W 25 KT...INLAND $$ FORECASTER AVILA