Forecast Discussion For Sunset Beach And Brunswick County
000 FXUS62 KILM 100825 AFDILM AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON NC 325 AM EST WED MAR 10 2010 .SYNOPSIS... A SLOW MOVING STORM SYSTEM APPROACHING FROM THE CENTRAL UNITED STATES WILL AFFECT THE CAROLINAS INTO THE WEEKEND. ACCOMPANYING THE STORM SYSTEM WILL BE INCREASING CHANCES FOR RAIN TONIGHT THROUGH FRIDAY. DRY WEATHER IS EXPECTED TO RETURN FOR THE LATTER HALF OF THE WEEKEND AND EARLY NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 3 AM WEDNESDAY...PLENTY OF UNCERTAINTY EXISTS IN THE FORECAST FOR THE NEXT 24 HOURS. MODEL INITIALIZATION HAS BEEN RATHER POOR WITH REGARDS TO THE AMOUNT OF DRY AIR IN PLACE AT THE LOW LEVELS OVER THE CENTRAL AND EASTERN CAROLINAS...AND WITH AN APPROACHING UPPER DISTURBANCE PRODUCING RAIN AND EMBEDDED CONVECTION ACROSS CENTRAL ALABAMA AND GEORGIA. NO MODEL APPEARS TO HAVE A GOOD HANDLE ON THE DRY AIR LOCALLY...AND THE 00Z NAM IS CLOSER TO REALITY THAN THE 00Z GFS WITH THE DISTURBANCE AND PRECIPITATION DISTRIBUTION OVER AL/GA. A DECAYING AREA OF RAIN SHOULD MOVE INTO THE PEE DEE REGION LATE THIS MORNING. PRECIPITATION WILL BE FALLING FROM A MID- LEVEL CLOUD DECK WITH CEILINGS IN THE 7000-8000 FT RANGE...MEANING PRECIPITATION AMOUNTS WILL BE LIGHT...ON THE ORDER OF A FEW HUNDREDTHS OF AN INCH OR SO. WHAT IS LEFT OF THIS INITIAL DISTURBANCE WILL MOVE INTO INTERIOR EASTERN NC THIS AFTERNOON AND A LULL IS EXPECTED IN PRECIPITATION COVERAGE ALTHOUGH MOSTLY CLOUDY SKIES WILL CONTINUE. TONIGHT...A COMPLICATED SCENARIO SHOULD LEAD TO SHOWERS BECOMING FAIRLY WIDESPREAD...ESPECIALLY AFTER MIDNIGHT AS A STRONGER UPPER DISTURBANCE BEARS DOWN ON THE CAROLINAS. THE MID-LEVEL FLOW WILL BACK TO THE SOUTHWEST WITH PRECIPITABLE WATER VALUES GROWING TO GREATER THAN ONE INCH. FORECAST SOUNDINGS SHOW THE STEADILY INCREASING MOISTURE...AND BY 12Z THURSDAY THE COLUMN IS PRETTY MUCH SATURATED FROM THE SURFACE ALL THE WAY UP. IN FACT THERMAL PROFILES ABOVE THE COOL BOUNDARY LAYER ASSUME A MOIST ADIABATIC PROFILE INDICATING PRECIPITATION MAY BECOME SHOWERY/CONVECTIVE IN NATURE. TEMPERATURES TODAY ARE GOING TO BE DIFFICULT...ESPECIALLY INLAND WHERE THE DEGREE OF EVAPORATIONAL COOLING AND UNCERTAINTY ABOUT RESIDUAL CLOUD COVERAGE THIS AFTERNOON EXISTS. MID 60S ARE FORECAST ALONG AND NEAR THE I-95 CORRIDOR WITH UPPER 60S TO NEAR 70 IN THE CAPE FEAR REGION AWAY FROM THE COAST. ALONG THE IMMEDIATE COAST A COOL FLOW OFF THE CHILLY NEARSHORE WATERS WILL KEEP HIGHS IN THE 59-63 RANGE. OUR FORECAST LOWS TONIGHT ARE SEVERAL DEGREES ABOVE MOS CONSENSUS GIVEN THICK CLOUD COVER EXPECTED AND LITTLE EVAPORATIONAL COOLING POTENTIAL GIVEN WHAT SHOULD BE A FAIRLY SATURATED AIRMASS BY THAT TIME...LOWS GENERALLY IN THE LOWER 50S MOST AREAS. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 3 AM WEDNESDAY...A WET SHORT TERM PERIOD AHEAD AS SLOW CHURNING STORM SYSTEM WHICH MAKES IT WAY SLOWLY EASTWARD FROM THE MISSISSIPPI VALLEY TOWARD THE MID ATLANTIC STATES BY FRI NIGHT. PLENTY OF GULF AND ATLANTIC MOISTURE WILL CONVERGE UPON THE COASTAL CAROLINAS ON THURS WITH A DECENT AMOUNT OF LIFT AND UPPER LEVEL SUPPORT TO PRODUCE WIDESPREAD PCP. PCP WATER UP TO NEAR 1.5 INCHES IN A SATURATED COLUMN. LOOKS LIKE PLENTY OF WAA WILL LIMIT BEST INSTABILITY...BUT WILL KEEP THUNDERSTORMS IN THE FORECAST ON THURSDAY. BY OVERNIGHT THURS INTO FRI SHOULD SEE QUITE A BIT OF DRIER AIR MAKING ITS WAY IN IN THE MID LEVELS. BETTER CHC OF SHWRS/TSTMS SHOULD COME BY LATE FRI AS ANOTHER IMPULSE WILL RIDE UP FROM THE GULF AS MAIN LOW CONTINUES TO TRACK EASTWARD. IT LOOKS LIKE BEST CONVECTION SHOULD REMAIN OVER THE ATLANTIC WATERS AND ANOTHER FOCAL POINT TO OUR WEST ASSOCIATED WITH MAIN LOW. MAY SEE MORE IN THE WAY OF ELEVATED INSTABILITY WITH THIS SECOND IMPULSE. OVERALL EXPECT DEFINITE PCP ON THURS WITH DECENT QPF...BUT WILL KEEP CLOUDS AND SHWRS HEADING INTO THE WEEKEND ALTHOUGH MORE UNCERTAINTY EXISTS AS LOW MOVES EASTWARD. TEMPS WILL REMAIN ON THE WARM SIDE THROUGH THURS WITH DECENT WAA ALTHOUGH CLOUDS AND PCP SHOULD KEEP THEM DOWN A BIT...EXPECT MOST PLACES IN THE MID 60S. FRI WILL BE ANOTHER WARM DAY WITH TEMPS UP AROUND 70. OVERNIGHT LOWS WILL REMAIN ABOVE 50 THURS NIGHT AND NEAR 50 FRI NIGHT. && .LONG TERM /SATURDAY THROUGH TUESDAY/... AS OF 3 AM WEDNESDAY...ANOTHER IMPULSE RIDING AROUND MAIN LOW PRESSURE SYSTEM EARLY SAT BUT DRIER AIR SHOULD MAKE ITS WAY IN ON THE BACK END OF THE LOW THROUGH THE DAY ON SAT. THIS PESKY CUTOFF LOW WILL CONTINUE TO MOVE SLOWLY EAST OVER THE MID ATLANTIC THROUGH THE EXTENDED PERIOD AND WILL FINALLY PUSH OFF SHORE BY TUES. A DRIER WESTERLY COMPONENT TO THE FLOW WILL DEVELOP HEADING INTO SAT AS LOW MAINTAINS ITSELF TO THE NORTH WHICH SHOULD HELP TO LIMIT PCP BY SAT AFTN. CAN NOT RULE OUT CLOUDS AND LIMITED PCP UNTIL LOW FINALLY WORKS ITS WAY OFF SHORE BY TUES. OVERALL WILL BE A DRIER FORECAST THROUGH THE LATTER HALF OF THE WEEKEND INTO EARLY NEXT WEEK. TEMPS WILL START OUT ABOVE NORMAL AGAIN ON SAT BUT WILL BEGIN TO COOL DOWN A FEW DEGREES THROUGH THE WEEKEND AND BY MON TEMPS MAY BE JUST BELOW CLIMO IN THE LOWER 60S MOST PLACES AS COOLER AND DRIER W-NW FLOW DEVELOPS. OVERNIGHT LOWS SHOULD BE AT OR ABOVE CLIMO THROUGH THE PERIOD. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... INCREASING MID CLOUDS ARE EXPECTED OVER THE NEXT SIX HOURS AS MOISTURE INCREASES STEADILY FROM THE WEST WELL IN ADVANCE OF A LARGE LOW PRESSURE SYSTEM. LIGHT SOUTHWEST SURFACE WINDS ARE EXPECTED AND WINDS WITHIN THE BOUNDARY LAYER WILL BE HIGH ENOUGH THAT NO FOG IS EXPECTED. LOOK FOR SHOWERS POSSIBLE BY LATE AFTERNOON OR THIS EVENING AS SOME WEAK ISENTROPIC LIFT BEGINS. CONDITIONS SHOULD REMAIN VFR THROUGH 00Z...WITH A SLIGHT CHANCE OF MVFR CEILINGS IF THE SHOWERS HAPPEN TO BECOME MODERATE. EXTENDED OUTLOOK...MEDIUM CONFIDENCE FOR PERIODS OF IFR/RAIN AND POSSIBLE THUNDERSTORMS AS APPROACHING STORM SYSTEM MOVES INTO THE AREA FOR THURSDAY. CONDITIONS WILL BE UNSETTLED THROUGH SATURDAY MORNING WITH INTERMITTENT LOW CEILINGS AND PRECIP. LOW CONFIDENCE FOR POSSIBLE SHOWERS FOR SUNDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 3 AM WEDNESDAY...HIGH PRESSURE WELL OFFSHORE WILL LOSE ITS INFLUENCE ON OUR WEATHER TODAY. LARGE LOW PRESSURE BACK IN THE CENTRAL PLAINS STATES WILL BEGIN TO CRAWL TO THE EAST...BRINGING AN INCREASE IN CLOUDS TODAY...WITH RAIN CHANCES INCREASING TONIGHT. WIND SPEEDS SHOULD REMAIN RATHER LIGHT HOWEVER...WITH SPEEDS REMAINING 12 KNOTS OR LESS UNTIL LATE TONIGHT. AIR TEMPERATURE CONTRASTS FROM LAND TO SEA WILL BE LESS THAN YESTERDAY WHICH WILL SUPPORT A WEAKER SEABREEZE CIRCULATION THIS AFTERNOON. WIND SPEEDS SHOULD STRUGGLE TO EXCEED 10 KNOTS THIS AFTERNOON ALONG THE SC COAST...WITH 10-12 KNOTS POSSIBLE ALONG THE NC COAST. SEAS AROUND 2 FT WILL BEGIN TO BUILD TONIGHT AS A LONG SOUTHERLY FETCH DEVELOPS. SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 3 AM WEDNESDAY...ON SHORE FLOW REALLY START TO PICK UP THU AS GRADIENT BECOMES PINCHED INCREASING UP NEAR 15 TO 20 KTS. THIS WILL PUSH SEAS UP THROUGH THURS WITH SCA CONDITIONS EXPECTED. SEAS WILL PEAK THURS NIGHT UP TO 7 TO 9 FT IN OUTER WATERS BEFORE DIMINISHING THROUGH FRI AS WINDS BECOME LIGHTER AND MORE VARIABLE. MAY SEE SEAS DOWN BELOW SCA BRIEFLY FRI NIGHT BUT THIS WILL BE SHORT LIVED AS WESTERLY WINDS WILL INCREASE THE OFF SHORE SEAS ONCE AGAIN BY SAT MORNING. LONG TERM /FRIDAY THROUGH SATURDAY/... AS OF 3 AM WEDNESDAY...PERSISTENT OFF SHORE WESTERLY FLOW WILL SET UP THROUGH THE WEEKEND AS LOW PRESSURE SYSTEM CONTINUES TO CHURN AND SITUATE ITSELF NORTH OF THE LOCAL WATERS. THIS SHOULD HELP EASE NEAR SHORE WATERS BUT EXPECT OFF SHORE SEAS TO REMAIN JUST ABOVE SCA SAT THROUGH MUCH OF SUNDAY. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...TRA NEAR TERM...TRA SHORT TERM...III LONG TERM...III AVIATION...TRA
NWS ILM Office Area Forecast Discussion
