FXUS64 KMOB 182339 AAA AFDMOB AREA FORECAST DISCUSSION...AVIATION UPDATE NATIONAL WEATHER SERVICE MOBILE AL 635 PM CDT TUE JUN 18 2013 .AVIATION [19.00Z TERMINAL FORECAST DISCUSSION]...VFR CONDITIONS WILL PREVAIL THROUGH MUCH OF THE PERIOD. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL DEVELOP DURING THE LATE MORNING AND AFTERNOON HOURS ON WEDNESDAY WITH LOCALIZED MVFR TO IFR CIGS/BR POSSIBLE TONIGHT INTO WEDNESDAY...PARTICULARLY NEAR SHRA/TSRA. /13 && .SHORT TERM [TONIGHT THROUGH WEDNESDAY]...WATER VAPOR IMAGERY AND RUC 500 MB ANALYSIS INDICATE A MOIST WESTERLY FLOW REGIME IS PERSISTING ACROSS MUCH OF THE SOUTHEASTERN U.S. THIS AFTERNOON. SURFACE LOW PRESSURE IS MEANWHILE CENTERED IN THE VICINITY OF NORTH CAROLINA/VIRGINIA...WHILE AN ASSOCIATED WEAK FRONTAL BOUNDARY REMAINS DRAPED SOUTHWESTWARD FROM THIS FEATURE ACROSS NORTHERN GEORGIA...ALABAMA AND MISSISSIPPI. MLCAPES ARE GENERALLY RANGING BETWEEN 1000-1500 J/KG ACROSS OUR FORECAST AREA THIS AFTERNOON... WHILE PRECIPITABLE WATER VALUES ARE MOSTLY AVERAGING BETWEEN 1.5 AND 2 INCHES. THIS MOIST AND UNSTABLE ENVIRONMENT...COMBINED WITH A WEAK EMBEDDED SHORTWAVE IMPULSE IN THE WESTERLY FLOW ALOFT HAS AIDED IN THE DEVELOPMENT OF SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS ACROSS INTERIOR PORTIONS OF SOUTHEAST MISSISSIPPI AND SOUTHWEST ALABAMA EARLY THIS AFTERNOON. THE WET MICROBURST RISK REMAINS IN THE MODERATE CATEGORY...SO A FEW STRONG PULSE STORMS WILL BE POSSIBLE THROUGH THE EARLY EVENING HOURS. THE MOIST WESTERLY FLOW PATTERN WILL PERSIST ACROSS OUR FORECAST AREA THROUGH WEDNESDAY. THE AFOREMENTIONED WEAK BOUNDARY WILL CONTINUE TO SAG SOUTHWARD AND WILL BECOME ORIENTED NEAR COASTAL PORTIONS OF THE FORECAST AREA BY EARLY WEDNESDAY MORNING. THE DEEP LAYER MOISTURE AXIS WILL ALSO CONTINUE TO EDGE SOUTHWARD TO NEAR THE COAST BY WEDNESDAY AFTERNOON. WE THEREFORE EXPECT SCATTERED SHOWERS AND THUNDERSTORMS TO CONTINUE TO DEVELOP ALONG AND AHEAD OF THE BOUNDARY THROUGH WEDNESDAY. PRECIPITATION CHANCES WILL BE MAINTAINED IN THE 40-50 PERCENT RANGE ACROSS MOST LOCATIONS TONIGHT INTO WEDNESDAY. FREQUENT LIGHTNING...GUSTY WINDS...AND VERY HEAVY RAIN WILL BE POSSIBLE AT TIMES WITH THE STRONGER STORMS THAT DEVELOP. LITTLE CHANGE WAS MADE TO THE TEMPERATURE FORECAST. LOWS TONIGHT SHOULD RANGE FROM NEAR 70 OVER THE INTERIOR TO THE MID 70S NEAR THE COAST. HIGHS WEDNESDAY LOOK TO MOSTLY RANGE FROM THE UPPER 80S TO AROUND 90. /21 .SHORT TERM [WEDNESDAY NIGHT THROUGH THURSDAY NIGHT]...SURFACE TROUGH WILL MOVE TOWARD THE CENTRAL GULF COAST ON WEDNESDAY EVENING AND OFFSHORE OVERNIGHT. IT WILL SERVE AS A FOCAL POINT FOR CONVECTION WITHIN A HIGH HUMIDITY BAND OF AIR...WHERE PRECIPITABLE WATER IS ABOUT 2 INCHES...ALIGNING ITSELF EAST TO WEST ALONG THE TROUGH AXIS. EASTWARD PASSAGE OF WELL DEFINED MID LEVEL DISTURBANCES AT THE BASE OF THE APPROACHING FEATURE WILL COMBINE WITH THERMODYNAMIC LIFTING FROM THE SURFACE AND DYNAMIC LIFTING BY THOSE UPPER VORTLOBES MENTIONED. THESE TWO TERMS WOULD BRING SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS. SOME WILL BRING HEAVY RAIN AND STRONG GUSTY WINDS. AFTER SUNSET BEFORE MIDNIGHT THE CONVECTION WILL DIE DOWN AND THE ATMOSPHERE WILL STABILIZE WHILE IT IS RECYCLING FALLEN RAINWATER INTO WATER VAPOR. SHOWERS AND THUNDERSTORMS WOULD INCREASE SOUTHWARD OFF THE COAST AFTER MIDNIGHT WEDNESDAY NIGHT TOWARD SUNRISE THURSDAY MORNING WITH THE AFOREMENTIONED SURFACE FEATURE BEING OFFSHORE AND THE LAND BREEZE SPINNING UP WHICH WE BELIEVE WOULD BOTH BRING A GREATER CHANCE OF RAIN THAN AFTER SUNSET. THE TROUGH ALOFT SHOULD MIGRATE EAST THURSDAY AND GIVE US A LESSER CHANCE FOR RAIN. /77 .LONG TERM [FRIDAY THROUGH MONDAY]...NO CHANGES. THE FORECAST AREA WILL REMAIN IN A GENERALLY HUMID MID LEVEL ZONAL FLOW THROUGH MUCH OF THE MEDIUM RANGE WITH A WEAK SURFACE TROUGH PRESENT TO THE EAST. THAT FEATURE SHOULD BE GONE BY SATURDAY EXPECT TO SEE ISOLATED TO SCATTERED SHOWERS/STORMS REMAINING IN THE OUTLOOK WITH SLIGHTLY MORE COVERAGE DURING THE DAYTIME WHEN HUMIDITY WILL BE HIGH HORIZONTALLY AND VERTICALLY...AND THERMODYNAMIC INSTABILITY INCREASES. DYNAMIC FORCES ALOFT APPEAR TO BE MUCH LESS THAN THEY ARE CURRENTLY SINCE A RIDGE ALOFT WILL BE BUILDING OVER THE REGION LATE THIS WEEK. /77 && .MARINE...SURFACE LOW PRESSURE WILL CONTINUE TO MOVE EASTWARD TO NEAR THE EASTERN SEABOARD TONIGHT...WHILE HIGH PRESSURE STRETCHES ACROSS SOUTHERN FLORIDA INTO THE NORTHERN GULF OF MEXICO. THE GRADIENT BETWEEN THESE TWO FEATURES WILL RESULT IN A MODERATE SOUTHWESTERLY WIND FLOW OVER THE MARINE AREA THROUGH TONIGHT. A LIGHT TO MODERATE SOUTHWEST TO NORTHWEST WIND IS EXPECTED WEDNESDAY-THURSDAY AS A WEAK COLD FRONT/PRESSURE TROUGH APPROACHES THE GULF COAST REGION. A LIGHT TO OCCASIONALLY MODERATE SOUTHEASTERLY TO SOUTHERLY FLOW PATTERN SHOULD DEVELOP BY THE END OF THE WEEK INTO THE WEEKEND AS HIGH PRESSURE BUILDS ACROSS THE SOUTHEASTERN STATES. WINDS AND SEAS WILL BE LOCALLY HIGHER NEAR ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. /21 && .PRELIMINARY POINT TEMPS/POPS... MOBILE 73 89 70 89 70 / 50 50 20 30 20 PENSACOLA 75 90 74 90 73 / 40 50 20 30 30 DESTIN 76 88 76 87 75 / 40 50 20 40 30 EVERGREEN 70 88 68 91 67 / 40 50 20 30 30 WAYNESBORO 70 88 65 90 65 / 40 40 20 20 20 CAMDEN 70 88 66 91 66 / 40 30 20 20 20 CRESTVIEW 71 91 69 92 67 / 50 50 20 40 30 && .MOB WATCHES/WARNINGS/ADVISORIES... AL...NONE. FL...NONE. MS...NONE. GM...NONE. && $$