859 FXUS64 KHUN 040557 AFDHUN AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE HUNTSVILLE AL 1157 PM CST SUN MAR 3 2013 .UPDATE... FOR 06Z TAFS && .DISCUSSION... /ISSUED 936 PM CST SUN MAR 3 2013/ OVERALL...THERE WERE NO SIGNIFICANT CHANGES MADE TO THE SHORT TERM GRIDS THIS EVENING...WITH THE COMBINATION OF BENIGN NORTHWEST FLOW ALOFT AND PRESENCE OF RIDGING IN THE LOWER-LEVELS MAINTAINING TRANQUIL WEATHER CONDITIONS ACROSS THE REGION. A WEAK MID-LEVEL VORT MAX EMBEDDED IN THE NORTHWEST FLOW REGIME WILL RESULT IN THE DEVELOPMENT OF THICKER ALTOSTRATUS CLOUDS ACROSS THE REGION OVERNIGHT. HOWEVER...THIS HIGHER-BASED CLOUD DECK SHOULD DO LITTLE TO PREVENT TEMPERATURES FROM FALLING INTO THE MID 20S IN AN OTHERWISE IDEAL RADIATIONAL COOLING ENVIRONMENT. KEEPING THIS IN MIND...MINOR ADJUSTMENTS WERE MADE TO LOWER MINIMUM TEMPERATURES -- WITH SUBSEQUENT CHANGES IN HOURLY TEMPERATURE/DEWPOINT/RH GRIDS. SKY COVER WAS ADJUSTED TO REFLECT A SLIGHTLY LATER ARRIVAL OF THICKER CLOUDS THIS EVENING...AND WIND GRIDS WERE ADJUSTED TO MATCH CURRENT OBS. UPDATED PRODUCTS HAVE ALREADY BEEN TRANSMITTED. 70/DD && .AVIATION... FOR 06Z TAFS...NO SIGNIFICANT CHANGES TO PREVIOUS AVIATION FORECAST REASONING. VFR CONDITIONS WILL PREVAIL AT BOTH HSV/MSL THRU THE VALID TAF PERIOD. HOWEVER...A VERY WEAK DISTURBANCE ALOFT WILL MOVE ACROSS THE REGION LATE TONIGHT RESULTING IN VFR ALTOSTRATUS CIGS BTWN 8-12 KFT DURING THE PERIOD FROM 04/06-10Z. ALTHOUGH THE ALTOSTRATUS DECK WILL LIKELY DIMINISH EARLY MONDAY MORNING...BKN CIRRUS WILL PERSIST FOR MOST OF THE DAY ON MONDAY. STRENGTHENING SOUTHERLY WINDS AND MOISTURE ADVECTION AHEAD OF AN APPROACHING STORM SYSTEM WILL RESULT IN A DECK OF LOWER STRATUS DEVELOPING AROUND OR JUST AFTER 05/00Z ALONG WITH AN INCREASING THREAT FOR SHRA -- ESPECIALLY BTWN 05/03-06Z. A LIGHT ESE RETURN FLOW WILL GRADUALLY BECOME ESTABLISHED BY 10-12Z...WITH SSE WINDS 10G18 KNOTS DEVELOPING BY 14Z AND CONTINUING FOR REMAINDER OF PERIOD. 70/DD && .HUN WATCHES/WARNINGS/ADVISORIES... AL...NONE. TN...NONE. && $$ FOR MORE INFORMATION PLEASE VISIT OUR WEBSITE AT WEATHER.GOV/HUNTSVILLE.