AFDHGX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX 1024 AM CDT THU MAY 12 2011 .UPDATE... A NEARLY 200 MILE N-S LINE OF CONVECTION APPROACHING AND PASSING THE I-35 CORRIDOR THIS MORNING...WITH SCATTERED CELLS AHEAD OF IT AFFECTING OUR NORTHWESTERN ZONES. THIS SOUTH CENTRAL TEXAS MCS WILL TRACK EASTWARD AND SHOULD REACH OUR WESTERN FRINGES AROUND NOON... WITH CELLULAR FILL-IN AHEAD OF IT INTO THE EVENING HOURS. THE UPPER LEVELS ARE STILL CONDUCIVE TO MUCH OF THE AREA RECEIVING RAIN...WITH ISOLATED THUNDER WITH A LOCAL SEVERE THREAT. 12/12Z ANALYSIS STILL DEPICTS A SPLITTING 25H JET OVER EAST TEXAS...WITH A LFQ RESIDING OVER MATAGORDA BAY. DOWNSTREAM ENVIRONMENT HAS THE DEEPEST MOISTURE CENTERED AROUND CRP (1.8 INCH PWAT) WITH STEEP MID-LEVEL LAPSE RATES ABOVE WEAK 7H CAPPING. AS CONVECTIVE TEMPERATURES IN THE LOWER-MIDDLE 80S ARE MET...AREA CAN EXPECT JUST SCATTERED CONVECTION TO BEGIN TO RIDE UP FROM THE WSW. STRONGEST STORMS HAVE THE POTENTIAL TO BECOME SEVERE WITH LARGE HAIL BEING THE MAIN THREAT. THE WINDOW OF BEST OPPORTUNITY WILL BE FROM MID-LATE AFTERNOON INTO THE LATE EVENING...OR GENERALLY WHEN THE UPPER TROUGH AXIS SWINGS INTO NORTH CENTRAL TEXAS. 31 .CLIMATE... DUE TO ACTIVE WEATHER...TODAY`S DROUGHT STATEMENT WILL BE ISSUED TOMORROW. 43 && .PREV DISCUSSION... /ISSUED 913 AM CDT THU MAY 12 2011/ UPDATE... A NEW ZFPHGX PRODUCT OUT TO COMMUNICATE THE SEVERE THUNDERSTORM WATCH THAT IS IN EFFECT THROUGH 20Z. 31 PREV DISCUSSION... /ISSUED 643 AM CDT THU MAY 12 2011/ AVIATION... THE SHOWERS AND THUNDERSTORMS THAT AFFECTED THE AREA OVERNIGHT HAVE WEAKENED AND MOVED EAST OF THE TERMINALS. WIDESPREAD MVFR CIGS WITH POCKETS OF IFR CONDITIONS BEING REPORTED ACROSS ALL OF SOUTHEAST TEXAS THIS MORNING AND THIS SHOULD CONTINUE INTO THE MID MORNING HOURS BEFORE CONDITIONS IMPROVE TO AT LEAST MVFR AREAWIDE. CONVECTION WILL LIKELY REDEVELOP ACROSS THE AREA BY MIDDAY AS AN UPPER LEVEL DISTURBANCE APPROACHES FROM THE WEST. GREATEST COVERAGE LIKELY ACROSS AREAS FROM IAH/HOU NORTHWARD THROUGH THE AFTERNOON HOURS. THUNDERSTORMS SHOULD COME TO AN END BY LATE THIS EVENING WITH CIGS LOWERING TO IFR LEVELS. 38 PREV DISCUSSION... /ISSUED 401 AM CDT THU MAY 12 2011/ DISCUSSION... AS ONE SYSTEM MOVES OUT TO THE EAST THIS MORNING...WATCH BOXES OUT TO THE WEST HERALDING THE POSSIBILITY OF MORE ACTIVITY HEADING FOR US LATER TODAY. SHORT TERM GUIDANCE (WHILE THEY DID INITIALIZE OK) NOT HANDLING THE PCPN THIS MORNING ALL THAT WELL. SO NOT FEELING A LOT OF CONFIDENCE WITH THEIR TAKE ON THINGS FOR THE AFTN. BUT THAT BEING SAID...THE WEAKENED CAP/ABUNDANT MOISTURE AND LIKELIHOOD FOR A RATHER UNSTABLE AIRMASS (WITH DAYTIME HEATING AS PER OF THE MESO HIGH IN THE WAKE OF THIS OVERNIGHT ACTIVITY) TO SET THE STAGE THIS AFTN FOR A DECENT CHANCE OF WIDESPREAD CONVECTION. AGAIN TIMING TO BE THE MAIN ISSUE TODAY WITH THE NEXT SHORTWAVE. BUT SHOULD ALL OF THIS COME TOGETHER THIS AFTN...THE SLIGHT RISK FOR SEVERE WX COULD VERIFY NICELY. CHC POPS TO REMAIN IN FOR TONIGHT/EARLY FRI MORNING WITH THE PASSAGE OF THE ASSOCIATED COLD FRONT. COOLER/DRIER CONDITIONS BY FRI NIGHT AS THE COLD FRONT MOVES ESEWD STEADILY WITH TIME. HIGH AMPLITUDE UPPER LEVEL RIDGE COMBINED WITH STRONG SFC HIGH SHOULD GIVE US A SPELL OF SPRING LIKE TEMPS DURING THE WEEKEND AND INTO THE EARLY PART OF NEXT WEEK. 41 MARINE... SEAS CONTINUE TO DECREASE ACROSS THE COASTAL WATERS AS ONSHORE FLOW BEGINS TO WEAKEN. WILL ALLOW SCEC TO EXPIRE AT DAYBREAK THIS MORNING FOR THE OFFSHORE WATERS. A COLD FRONT WILL PUSH OFF THE COAST ON FRIDAY BRINGING MODERATE OFFSHORE WINDS IN ITS WAKE. CAUTION FLAGS WILL LIKELY BE NEEDED ON SATURDAY DUE TO THE STRONGER OFFSHORE FLOW. ONSHORE WINDS WILL RETURN BY THE MIDDLE OF NEXT WEEK. 38 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 87 68 84 55 80 / 80 50 20 0 0 HOUSTON (IAH) 88 71 89 61 81 / 60 50 30 10 0 GALVESTON (GLS) 84 74 85 66 80 / 50 40 30 10 0 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 1 PM CDT THIS AFTERNOON FOR THE FOLLOWING ZONES: MATAGORDA BAY...WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM... WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM. SMALL CRAFT ADVISORY UNTIL 11 AM CDT THIS MORNING FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM. SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 1 PM CDT THIS AFTERNOON FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM. && $$