AFDAKQ AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WAKEFIELD VA 139 AM EDT THU MAY 12 2011 .SYNOPSIS... HIGH PRESSURE REMAINS OVER THE REGION THROUGH THURSDAY...PROVIDING DRY AND SEASONABLE CONDITIONS ACROSS THE AREA. A SLOW MOVING LOW PRESSURE SYSTEM WILL AFFECT THE REGION LATE FRIDAY THROUGH THE FIRST PART OF NEXT WEEK. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... LTST MSAS SHOWING HIGH PRS OVRHD WITH MID LVL DEBRIS CLOUDS FROM UPSTREAM CONVECTION APPRCHG WRN CNTYS. SO XPCT A M CLR TO PT CLDY NITE AHEAD WITH A LGHT ONSHORE FLOW. CONCERN TURNS TO PTCHY FOG DVLPMNT LATE TONITE (SPCLLY ERN SCTNS). ALTHOUGH IT APPEARS THAT SOME PTCHY FOG WILL DVLP...CONFIDENCE NOT HIGH ENUF FOR ANY WDSPRD FOG DVLPMNT TO ADD TO GRIDS / FCST ATTM. MIDNITE SHIFT MAY NEED TO ADD SOME FOG B4 SUNRISE DEPENDING ON TRENDS OVR THE NXT SVRL HRS. LOWS M40S-L50S. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/... GOING WITH A COMBINATION OF THE LATEST GFS/ECMWF MDLS FOR THE FCST FM THU THRU SAT. THESE TWO MDLS IN GENERAL AGREEMENT WITH THE OVRALL SYNOPTIC PATTERN CHANGE...WITH THE UPR RDG SLOWLY SHIFTING EWRD ACRS THE REGION AND OFF THE CST...WHILE UPR/SFC LO PRES MOVES FM THE CNTRL PLAINS EWRD INTO THE OH/TN VALLEYS. THIS WILL RESULT IN A GRADUAL INCRS IN LO LVL MOIST (DWPTS) AND THUS CLDS...AND THE CHC FOR SCTD SHOWERS AND TSTMS FM FRI THRU SAT. THE BEST CHCS FOR SCTD SHOWERS AND TSTMS WILL BE OVR THE WRN HALF OF THE AREA FRI AFTN/NGT...THEN DECENT CHCS EVERYWHERE ON SAT AS DEEPER MOIST/BETTER LIFT OVRSPREADS THE ENTIRE REGION. MAX TEMPS RANGING FM THE UPR 60S TO UPR 70S THU THRU SAT...WITH MIN TEMPS RANGING THRU THE 50S THU NGT...AND IN THE MID 50S TO NEAR 60 FRI NGT. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AN UPPER LOW WILL SLOWLY DROP FROM THE MID MISSISSIPPI VALLEY TO THE SOUTHEAST LATE THIS WEEKEND AND EARLY NEXT WEEK. THERE IS INCREASING CONFIDENCE OF A WET PATTERN DEVELOPING ACROSS THE LOCAL AREA...BUT IT IS TOO EARLY TO DETERMINE EXACT TIMING AND ORGANIZATION (SHOWERS WITH OCCASIONAL THUNDER VERSUS PRIMARILY THUNDERSTORMS) AS CONFIDENCE IS LOW IN THE EXACT DETAILS...SO 30 TO 40 POPS FOR SHOWERS AND THUNDERSTORMS WILL BE MAINTAINED. HIGH TEMPERATURES SHOULD REMAIN AROUND SEASONAL AVERAGES...WITH LOW TEMPERATURES SLIGHTLY ABOVE NORMAL WITH CLOUDS AND OCCASIONAL PRECIPITATION. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... WK SFC HI PRES RMNG OVR THE RGN...AND GENLY VFR CONDS WL PREVAIL THROUGH TAF PD. LGT ESE WNDS MAY RESULT IN LO STRATUS/PTCHY FG IN THE NEXT FEW HRS. CONTG TO MONITOR AREA OF CIGS 5-8KFT W OF I95...HAS SHOWN A LTL MVMNT E OVR THE PAST FEW HRS. OTRW...DURG DYTM...XPCTG SCT/BKN CU ALG W/ ESE WNDS CONTG. A SIMILAR SITU FOR TNGT/FRI MRNG. HIER PROB OF SCT SHRAS/TSRAS FM FRI AFTN THROUGH THE WKND. && .MARINE... SURFACE HIGH PRESSURE WILL REMAIN ANCHORED ALONG THE EAST COAST THROUGH FRIDAY. MEANWHILE...LOW PRESSURE WILL REMAIN QUASI-STATIONARY OFF THE MID ATLANTIC COAST. THIS WILL ALLOW FOR PERSISTENT NE FLOW AND SWELL WITH SEAS REMAINING AT OR ABOVE 5FT THROUGH AT LEAST THE END OF THE WEEK. HIGH PRESSURE SLOWLY MOVES OFF THE MID ATLANTIC COAST THIS WEEKEND AS LOW PRESSURE MOVES INTO THE OHIO VALLEY TURNING THE WIND TO SE. SEAS MAY REMAIN AROUND 5FT INTO THE WEEKEND DEPENDING ON HOW MUCH OF AN ONSHORE COMPONENT IS MAINTAINED IN THE WIND FIELD. THE CURRENT SCA WAS EXTENDED THROUGH FRIDAY NIGHT AND IT MAY EVENTUALLY NEED TO CONTINUE INTO THE WEEKEND. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT SATURDAY FOR ANZ650-652- 654-656-658. && $$ SYNOPSIS...TMG