Area Forecast Discussion Issued by NWS Wakefield, VA
000
FXUS61 KAKQ 141951
AFDAKQ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
351 PM EDT FRI JUN 14 2013
.SYNOPSIS...
HIGH PRESSURE BUILDS ACROSS THE GREAT LAKES BEFORE SETTLING OVER THE
MID ATLANTIC REGION TONIGHT AND SATURDAY...BEFORE SHIFTING OFF THE
COAST SATURDAY NIGHT AND SUNDAY. A WEAK COLD FRONT APPROACHES FROM
THE NORTHWEST LATER SUNDAY INTO SUNDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
NORTH TO NORTHWEST FLOW WILL CONTINUE TO BRING IN A COOLER
TEMPERATURES OVERNIGHT AS THE AREA IS BETWEEN LOW PRESSURE OVER THE
ATLANTIC AND HIGH PRESSURE OVER THE GREAT LAKES. THIS DRY/COOL FLOW
WILL HELP TO CLEAR SKIES THIS EVENING AND BRING OVERNIGHT LOW TEMPS
GENERALLY 5F DEGREES BELOW AVERAGE...WITH TEMPS DROPPING INTO THE
UPPER 50S.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY NIGHT/...
MID LEVEL TROUGH PULLS WELL OFF THE COAST SATURDAY...AS SURFACE HIGH
PRESSURE MOVING FROM THE GREAT LAKES CENTERS OVER THE MID ATLANTIC
REGION. THE MID/UPPER LEVEL PATTERN BECOMES MORE ZONAL SATURDAY
NIGHT AND SUNDAY AS A TROUGH DIGS ACROSS THE NORTHERN PLAINS
FLATTENING AND SHUNTING UPPER RIDGING EASTWARD.
THIS WILL PRODUCE A STEADY WARMING TREND WITH HIGHS SATURDAY
RETURNING TO NEAR NORMAL (LOW TO MID 80S). HIGHS CONTINUE TO RISE
SUNDAY REACHING THE UPPER 80S TO AROUND 90 FOR SUNDAY INTO MONDAY.
EXPECT DRY AND MOSTLY CLEAR/SUNNY FOR SAT INTO SUN. A WEAKENING
SHORTWAVE TROUGH CROSSES THE CENTRAL APPALACHIANS SUNDAY AFTERNOON
BRINGING A CHANCE OF THUNDERSTORMS TO THE NORTHERN PORTION OF THE
AREA ALONG WITH INCREASING CLOUD COVER. CHANCES FOR SHOWERS AND
THUNDERSTORMS LINGER THROUGH MONDAY AS WEAK SHORTWAVE ENERGY SWINGS
THROUGH THE AREA.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
MEDIUM/EXTENDED RANGE MODELS IN GOOD AGREEMENT WITH THE OVERALL
AMPLIFIED PATTERN DURING THE EXTENDED...FEATURING A STRONG TROUGH IN
THE WEST...STRONG RIDGING OVER THE PLAINS AND TROUGHING OVER THE NE.
THE MID ATLANTIC REGION WILL BE STUCK BETWEEN AFOREMENTIONED NE
TROUGH AND HIGH PRESSURE OFF THE SE COAST. OTHERWISE...MODELS
STRUGGLE ON HANDLING SEVERAL EMBEDDED SHORTWAVES IN THE UPPER FLOW.
THE FIRST OF WHICH IS PROGGED TO IMPACT THE REGION TUES. SHORTWAVE
ENERGY WILL DIG SEWD OUT OF S CNTRL CANADA OVER THE GREAT LAKES
REGION MONDAY NIGHT. AS THIS OCCURS...A COLD FRONT WILL PROGRESS EWD
FROM THE OH/TN VALLEYS...REACHING THE LOCAL AREA TUESDAY
AFTERNOON/EVENING. 14/12Z GFS DIGS STRONGER SHORTWAVE FARTHER SOUTH
THAN OTHER GUIDANCE...DEVELOPING A SFC LOW ALONG THE FRONT OVER THE
OH VALLEY. OTHER GUIDANCE WEAKENS THE SHORTWAVE OVER THE NE...WITH
THE SFC LOW LIFTING OVER THE NE INTO SE CANADA. SENSIBLE WEATHER
IMPACTS WILL BE DAYTIME TEMPS AND RAINFALL CHANCES. MOISTURE RETURN
WILL BE SOMEWHAT LIMITED...BUT SHOULD BE ENOUGH TO PROVIDE FOR
SCATTERED SHOWERS/THUNDERSTORMS TUES...MOSTLY IN THE AFTERNOON AND
EVENING. FRONT FORECAST TO CLEAR THE COAST TUES NIGHT...BRINGING AN
END TO POPS. THEREAFTER...CYCLONIC FLOW ALOFT WILL REMAIN ANCHORED
OVER THE ERN CONUS AS HIGH PRESSURE BUILDS IN AT THE SFC. DRY
CONDITIONS FORECAST TO PREVAIL THROUGH THE END OF THE WEEK.
ALTHOUGH...WILL NEED TO MONITOR A BOUNDARY LIFTING NWD ON FRIDAY.
TEMPS WILL REMAIN RIGHT AROUND NORMAL FOR THIS TIME OF YEAR. HIGHS
GENERALLY IN THE MID/UPPER 80S WITH OVERNIGHT LOWS IN THE MID/UPPER
60S.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
VFR CONDITIONS WILL CONTINUE THROUGH THE UPCOMING TAF PERIOD. GUSTY
N-NW WINDS DIMINISH LATE THIS AFTERNOON, BECOMING LIGHT AND
VARIABLE AFTER 22Z/6PM AS HIGH PRESSURE CONTINUES TO BUILD IN FROM
THE NW.
OUTLOOK...VFR AND DRY WEATHER EXPECTED OVER THE WEEKEND. CHANCES
FOR DIURNALLY DRIVEN SHOWERS AND THUNDERSTORMS RETURNS FOR MONDAY
AND TUESDAY AS SEVERAL WEAK SYSTEMS PUSH ACROSS THE REGION.
&&
.MARINE...
CONDITIONS WILL QUICKLY IMPROVE OVER THE WATERS THIS EVENING AS THE
PRESSURE GRADIENT RELAXES. NLY WINDS WILL DIMINISH TO AOB 15 KT
TONIGHT. SEAS WILL QUICKLY SUBSIDE TO BELOW 4 FT THIS EVENING. HIGH
PRESSURE WILL BUILD OVER THE REGION TONIGHT AND SATURDAY...BEFORE
SLIDING OFF THE SOUTHEAST COAST SATURDAY NIGHT INTO SUNDAY. LIGHT
OFFSHORE WINDS AOB 10 TO 15 KT THROUGH SAT NIGHT. ON SUNDAY...LOW
PRESSURE WILL TRACK THROUGH THE NE...INCREASING THE PRESSURE
GRADIENT OVER THE WATERS. SWLY WINDS WILL INCREASE TO 15 KT OVER THE
BAY AND 15 TO 20 KT OVER THE COASTAL WATERS. A COLD FRONT WILL
APPROACH THE WATERS MONDAY...BEFORE CROSSING THE REGION TUESDAY
AFTERNOON. THEREAFTER...HIGH PRESSURE WILL RETURN WITH SUB SCA CONDS.
&&
.HYDROLOGY...
FLOOD WARNING FOR THE BLACKWATER AT FRANKLIN CONTINUES, WITH THE
LATEST FORECAST SHOWING A GRADUAL DROP BELOW FLOOD STAGE BY LATE
FRIDAY NIGHT/EARLY SATURDAY MORNING.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR
ANZ631>634-638-650-652-654-656-658.
&&
$$
SYNOPSIS...AJZ/DAP
NEAR TERM...AJZ/DAP
SHORT TERM...AJZ/DAP
LONG TERM...SAM
AVIATION...MAM
MARINE...SAM
HYDROLOGY...