Area Forecast Discussion
Issued by NWS Wakefield, VA

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KAKQ 250003 AFDAKQ AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WAKEFIELD VA 803 PM EDT FRI APR 24 2015 .SYNOPSIS... HIGH PRESSURE WILL SHIFT OFFSHORE THROUGH TONIGHT...AHEAD OF LOW PRESSURE APPROACHING FROM THE PLAINS STATES. A WARM FRONT LIFTS INTO THE CAROLINAS ON SATURDAY AS THE SYSTEM APPROACHES FROM THE WEST TOMORROW THROUGH TOMORROW NIGHT...BEFORE PUSHING OFFSHORE SUNDAY. HIGH PRESSURE SLOWLY REBUILDS OVER THE AREA FROM THE WEST EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... SFC HIGH PRESSURE IS IN PLACE FROM THE OHIO VALLEY TO THE CAROLINA COAST. ALOFT...UPPER LEVEL LOW CONTINUES TO DRIFT E-NE OVER ATLANTIC CANADA. MEANWHILE TO THE WEST...UPPER LEVEL RIDGING OVER THE MS VLY CONTINUES TO PUSH EAST AS AN UPPER LEVEL DISTURBANCE LIFTS OUT OF THE DESERT SOUTHWEST. TONIGHT...AFOREMENTIONED UPPER SYSTEM OVER THE ROCKIES WILL SPIN UP A SURFACE LOW OVER THE CENTRAL PLAINS THIS EVENING, WHICH WILL SWING EAST INTO THE MID MISSOURI VALLEY LATE TONIGHT. THE ASSOCIATED WARM FRONT LIFTS ACROSS THE MID-SOUTH AND SOUTHEAST LATE TONIGHT AS A PIECE OF THE SFC HIGH PUSHES OFFSHORE OF THE SOUTHEAST COAST. THE UPPER LOW WILL SHIFT UPPER RIDGE EAST... BECOMING ORIENTED FROM THE OHIO VALLEY INTO THE SOUTHEAST OVERNIGHT. RESULTANT MID LVL FLOW SWITCHES AROUND TO THE W-SW WITH PW VALUES INCREASING GRADUALLY OVERNIGHT. MID TO HIGH CLOUDS WL INCREASE AND THICKEN ACROSS THE VA PIEDMONT AFTER MIDNIGHT. OVERALL...NOT AS COLD WITH LOWS IN THE UPPER 30S OVER THE EASTERN SHORE TO LOW-MID 40S SOUTH/SOUTHWEST ZONES. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/... ASSOCIATED SFC LOW WILL PUSH EAST THROUGH THE DAY ON SATURDAY, AS INCREASING/AMPLIFYING W-SW FLOW OVER THE SE CONUS LIFTS THE SHARPENING WARM FRONTAL BOUNDARY NE ACROSS THE WESTERN CAROLINAS THROUGH THE DAY. SFC HIGH OFFSHORE RIDGES BACK INLAND, BRIEFLY SETTING UP A NARROW CORRIDOR OF WEAK INSITU CAD WEDGING OVER THE PIEDMONT, WHICH WILL BE STRENGTHENED BY THE FIRST SLUG OF LIGHT OVERRUNNING MOISTURE FALLING INTO COOL/DRY AIRMASS SATURDAY MORNING. WHILE LITTLE MORE THAN SOME SCATTERED LIGHT SHRAS ARE EXPECTED EARLY SAT, COOL AND INCREASINGLY CLOUDY CONDITIONS ARE LIKELY, WITH MORE WIDESPREAD RAIN CHANCES BY AFTERNOON. INFLUX OF BEST ISENTROPIC LIFT BRINGS A PERIOD OF LIGHT TO OCCASIONALLY MODERATE RAINFALL LATE SAT AFTN/NIGHT. SRN STREAM ENERGY LIFTING FROM THE GULF STATES SAT NIGHT WILL LIKELY DEVELOP A WAVE OF LOW PRESSURE ALONG THE LIFTING WARM FRONT TO THE SOUTH AS THE ORIGINAL LOW WEAKENS OVER THE OH VALLEY. A COASTAL LOW STRENGTHENS ALONG THE FRONT...WITH CHANCES FOR PATCHY LIGHT RAIN CONTINUING INTO SUNDAY MORNING BEFORE BEST CHANCES TRANSITION TO THE COAST (ERN VA/NE NC) SUN AFTERNOON. HOWEVER, WITH RELATIVELY SHALLOW ISENTROPIC LIFT AVAILABLE, EXPECT QPF TO BE ON THE ORDER OF A COUPLE OF TENTHS OR LESS DURING THIS TIMEFRAME. QPF FOR THE WEEKEND BETWEEN A HALF AND THREE-QUARTERS OF AN INCH, HIGHEST SOUTH-SOUTHEAST. RATHER STAGNANT PATTERN PERSISTS SUNDAY NIGHT THROUGH EARLY NEXT WEEK WITH DEEP UPPER LEVEL LOW PRESSURE ANCHORED OVER EASTERN NEW ENGLAND. MODELS CONTINUE TO LINGER THE UPPER LOW NEARLY IN PLACE, IF NOT SLIDING SOUTH ALONG THE MID-ATLANTIC COAST THROUGH MIDWEEK AS WEAK UPPER RIDGING RUNS UP AGAINST THE NORTHEAST UPPER LOW. MODELS REMAIN IN GOOD AGREEMENT WITH ROTATING A COUPLE OF SHORTWAVES THROUGH AROUND THE BASE OF THE UPPER LOW ON MON, WITH LITTLE MORE THAN CONTINUED CLOUDY AND COOL CONDITIONS SUNDAY NIGHT AND MON (HIGHEST CLOUD COVER NORTHEAST, PARTLY SUNNY SOUTHWEST). FOR TEMPS, COOL/DAMP/CLOUDY CONDITIONS WILL RESULT IN HIGHS IN THE MID-UPPER 50S (ROUGHLY -1 TO -1.5 STD DEV) SAT, WITH TEMPERATURES DROPPING OFF AT ONSET OF STEADIER PCPN SAT AFTN. LOWS IN THE MID 40S TO LOW 50S SAT NIGHT. HIGHS SUNDAY REMAIN COOL IN CLOUDY AND SHOWERY CONDITIONS...MAINLY UPPER 50S TO NEAR 60, THOUGH SLIGHT COOLER LOW TO MID 50S ACROSS THE NORTH. EARLY MORNING LOWS SUNDAY NIGHT MAINLY IN THE 40S, WITH HIGHS MONDAY WARMING INTO THE 60S. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... AS UPPER RIDGING OVER THE WRN CONUS SHIFTS NE FROM THE NRN ROCKIES TO THE NRN PLAINS LATER TUE/WED...AN UPPER LOW WILL GRADUALLY WEAKEN/SHIFT OFF THE EAST COAST. THE MID ATLANTIC REGION LOOKS TO BE LOCATED IN-BETWEEN SYSTEMS MON NIGHT INTO EARLY WED WITH WEAK SFC HIGH PRESSURE OVER THE AREA. WILL HAVE DRY CONDITIONS AND PARTLY /MOSTLY SUNNY SKIES. REMAINING COOL WITH HIGHS MAINLY IN THE 60S...PERHAPS ONLY THE UPPER 50S AT THE COAST. LOWS IN THE 40S. EXPECT INCREASING SW FLOW ALOFT LATER WED INTO THU...BRINGING OVERRUNNING AND A CHANCE FOR PRECIP STARTING LATER WED AND LASTING INTO THU. GFS/ECMWF BOTH DEVELOP A COASTAL LOW BY THU...ALTHOUGH THE 12Z ECMWF IS STRONGER/CLOSER TO THE COAST WITH THE SFC LOW AND WOULD INDICATE A SOAKING RAIN FOR SE VA AND NE NC. THE 12Z GFS IS MORE PROGRESSIVE AND FARTHER OFFSHORE AND WOULD ONLY INDICATE MINIMAL PCPN CHANCES OVER THE LOCAL AREA. FOR NOW...WILL GO WITH A BLEND OF THE MODELS AND HAVE POPS IN THE 30-40% RANGE FROM LATER WED THROUGH THU ALTHOUGH STILL SOME UNCERTAINTY IN THE TRACK/DEVELOPMENT OF THE SFC LOW. DRY WX IS INDICATED FOR NEXT FRIDAY INTO NEXT WEEKEND. HIGHS MAINLY IN THE 60S...WITH LOWS IN THE MID 40S TO LOW 50S ON THURS. HIGHS IN THE 60S TO LOW 70S NEXT FRIDAY. && .AVIATION /00Z SATURDAY THROUGH WEDNESDAY/... VFR CONDITIONS ARE IN PLACE TO BEGIN THE PERIOD AS SURFACE HIGH PRESSURE THAT STRETCHES FROM THE GREAT LAKES SEWD OFF THE NC COAST. SOME HIGH CIRRUS IS BEGINNING TO SLIDE OVER THE REGION THOUGH AND IS THE FORE RUNNER OF AN APPROACHING SYSTEM FOR SATURDAY. THE SURFACE HIGH WILL SPLIT OVERNIGHT WITH PART OF THE HIGH SLIDING OFF THE SE COAST WHILE THE REMAINDER LIFTS BACK TO THE NORTH. BUT WINDS WILL STILL REMAIN LIGHT WITH JUST A THICKENING CIRRUS DECK. SO VFR CONDITIONS WILL PREVAIL ALL NIGHT. ON SATURDAY...A STRONG LOW PRESSURE SYSTEM OVER THE CENTRAL PLAINS WILL BEGIN TO SLIDE EWD WITH MOSITURE LIFTING NEWD FROM THE GULF COAST. THE CLOUDS WILL THICKEN AND THE CEILINGS LOWER THROUGH OUT THE LATE MORNING AND EARLY AFTERNOON PERIODS BEFORE LIGHT RAIN DEVELOPS LATE IN THE DAY...AFTER 20Z. ONCE THE RAIN BEGINS...EXPECT CEILINGS AND VISIBILITY TO LOWER TO MVFR OR IFR LEVELS. AT THE MOMENT...HAVE JUST SHOWN A GENERAL TREND TO MVFR CONDITIONS...BUT EXPECT TO SEE CEILINGS DROP BELOW 1K FT WITH VSBY 1-3 SM...BUT TIMING OF THE DETEORIATION STILL IN QUESTION AS IT MAY BE AFTER 00Z ON THE 26TH. OUTLOOK...RAIN CONTINUES SATURDAY NIGHT INTO SUNDAY WITH WIDESPREAD IFR CONDITIONS. DRY AND VFR CONDITIONS ARE EXPECTED BY SUNDAY EVENING OR EARLY MONDAY WHICH CONTINUE INTO WEDNESDAY. THE CHANCE FOR RAIN ARRIVES LATE WEDNESDAY OR WEDNESDAY NIGHT. && .MARINE... WINDS CONTINUE TO TREND DOWNWARD THIS AFTERNOON AND SEAS REMAIN BELOW 5 FT. THEREFORE...ALL SCA`S WILL EXPIRE AS OF 4 PM. HIGH PRESSURE SLOWLY BUILDS OVER THE WATERS THROUGH TONIGHT. SUB-SCA MARINE CONDITIONS PREVAIL TONIGHT THROUGH SAT WITH WITH WEAK HIGH PRESSURE PROGRESSING OFFSHORE. A WEAK SFC LOW DEVELOPS OVER THE OHIO RIVER VALLEY AND PASSES ACROSS SOUTHERN VA AND OFFSHORE SUNDAY. E-SE WINDS 10-15 KT SAT NIGHT/SUN MORN BECOME N-NE SUN AFTN/EVE W/ SPEEDS INCREASING TO SCA LEVELS AS THE LOW MOVES OFFSHORE. WINDS DIMINISH BELOW SCA LEVELS SUN NIGHT...BEFORE POSSIBLY RAMPING BACK UP AGAIN ON MONDAY WITH LOW PRESSURE OFF THE NEW ENGLAND COAST. WAVES BUILD BACK TO 3-4 FT ON THE BAY ON SUNDAY...WITH SEAS BUILDING TO 4-6 FT ON THE OCEAN. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...NONE. && $$ SYNOPSIS...MAM NEAR TERM...MAM SHORT TERM...MAS/MAM LONG TERM...JDM AVIATION...ESS MARINE...JDM

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.