TD # 2 Forms…


DATA FROM SATELLITES…NOAA RECONNAISSANCE AIRCRAFT…AND SURFACE OBSERVATIONS INDICATE THE LARGE LOW PRESSURE SYSTEM OVER THE WESTERN GULF OF MEXICO HAS ACQUIRED ENOUGH ORGANIZATION TO BE CLASSIFIED AS A TROPICAL DEPRESSION. ALTHOUGH INNER-CORE CONVECTION HAS WANED OVER THE PAST FEW HOURS…OUTER CONVECTIVE BANDING TO THE EAST OF THE CENTER HAS BEEN INCREASING. DROPSONDE DATA FROM TWO NOAA AIRCRAFT ON A RESEARCH MISSION IN AND AROUND THE DEPRESSION INDICATE SURFACE WINDS NEAR 30 KT IN THE EASTERN SEMICIRCLE…AND THIS WAS USED AS THE INITIAL INTENSITY FOR THIS ADVISORY.

THE INITIAL MOTION IS AN UNCERTAIN 310/10 DUE TO THE LOW-LEVEL CENTER REFORMING WITHIN THE EARLIER CENTRAL CONVECTION. ALTHOUGH THERE MAY BE SOME ERRATIC MOTION AS A RESULT OF POSSIBLE FURTHER REFORMATION OF THE SYSTEM CENTER…THE GENERAL MOTION SHOULD BE TOWARD THE NORTHWEST FOR THE NEXT 12 HOURS OR SO…FOLLOWED BY A GRADUAL TURN TOWARD THE WEST-NORTHWEST. ALL OF THE AVAILABLE MODEL GUIDANCE IS CONSISTENT ON A RIDGE OF HIGH PRESSURE BUILDING STEADILY SOUTHWESTWARD FROM THE EASTERN U.S. INTO THE EASTERN AND CENTRAL GULF OF MEXICO DURING THE NEXT 48 HOURS…WHICH SHOULD ACT TO STEER THE CYCLONE TOWARD THE TEXAS-MEXICO BORDER AREA. THE FORECAST TRACK IS DOWN THE MIDDLE OF THE TIGHTLY PACKED MODEL GUIDANCE SUITE.

WATER TEMPERATURES AHEAD OF THE DEPRESSION ARE ABOVE 28C AND THE VERTICAL WIND SHEAR IS RELATIVELY LOW…SO THE DEPRESSION HAS ABOUT 24 HOURS OR SO OF FAVORABLE CONDITIONS BEFORE LANDFALL OCCURS. AS A RESULT…SLOW INTENSIFICATION IS EXPECTED UP UNTIL THAT TIME. THE SHIPS MODEL BRINGS THE INTENSITY UP TO 46 KT BY LANDFALL…BUT DUE TO THE LARGE SIZE OF THIS SYSTEM…A SLOWER INTENSIFICATION RATE SIMILAR TO THE LGEM MODEL IS EXPECTED.

THE PRIMARY THREAT WITH THIS SYSTEM IS EXPECTED TO BE HEAVY RAINFALL OCCURRING ON TOP OF ALREADY SATURATED GROUND AND RAIN-SWOLLEN CREEKS AND RIVERS…WHICH WILL ONLY ADD TO FLOOD CONDITIONS ALREADY BEING EXPERIENCED ACROSS PORTIONS OF SOUTHERN TEXAS ANDNORTHEASTERN MEXICO CAUSED BY FORMER HURRICANE ALEX.

WVUA Meteorologist Richard Scott

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Wednesday Afternoon Weather Update – 3:29 PM

A good Wednesday to you! Our weather will continue hot this afternoon, as temperatures continue in the lower to middle 90s. A stray shower or storm is possible as the evening hours progress. Any storms across our area will end after sunset tonight, as skies remain mostly clear. Thursday could be the hottest day so far this year, with highs near 99 degrees. Some backyard thermometers could reach 100 during the mid afternoon hours. Expect no rain tomorrow and sunny skies. Heat index values will easily reach 108 on Thursday.

Our intense summer ridge will back down a bit over the weekend, and will allow for a cold front to make it into north Alabama. This will bring more clouds and enhance our rain chances on Saturday and Sunday. Highs will cool off just a bit, as temperatures reach the lower 90s on Saturday and Sunday. Expect a good coverage of shower and storms both days. Rain chances will remain fairly good for the remainder of the forecast period, with scattered afternoon storms possible each day through early next week. Humid weather can be expected each day, and highs will reach the lower 90s. This will drive the heat index values into the triple digits.

The tropics remain fairly active, as we are watching several areas. The National Hurricane Center is concerned about a tropical low in the western Gulf of Mexico. This could become a tropical storm before moving into south Texas. Be sure to join me tonight at 5, 6, and 10 PM for more on your local weather on WVUA-TV. Have a great day!

Richard Scott

WVUA Meteorologist