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000
FXUS61 KAKQ 182339
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
739 PM EDT SAT MAY 18 2013

.SYNOPSIS...
A WEAK FRONT REMAINS NEARLY STATIONARY OVER NORTH CAROLINA TONIGHT. THIS
FRONT IS EXPECTED TO LIFT TO THE NORTH ON SUNDAY...AND MOVE NORTH
OF THE REGION BY MONDAY AFTERNOON. A RIDGE OF HIGH PRESSURE OFF THE
SOUTHEAST COAST WILL PREVAIL INTO THE MIDDLE OF THE WEEK.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
LATEST WX ANALYSIS CONTINUES TO DEPICT A STATIONARY FRONT/BOUNDARY
OVER NC...WITH A RATHER BROAD MID/UPPER LEVEL TROUGH SITUATED FROM
KY DOWN INTO THE CAROLINAS. RADAR RETURNS HAVE DIMINISHED OVER
MUCH OF THE AREA OVER THE PAST FEW HRS...BULK OF SHOWER ACTIVITY
NOW CONFINED TO THE PENINSULA/HAMPTON ROADS AND EASTERN SHORE...WITH
A CLUSTER OF TSTMS OVER NE NC (HAVE 60-80% POPS IN THESE AREAS).
ELSEWHERE...HAVE DROPPED POPS DOWN TO ABOUT 30-40% THROUGH THE
REMAINDER OF THE EVENING HRS.

TOUGH CALL AS TO OVERNIGHT COVERAGE OF PRECIP...AS SHORTWAVE
ENERGY LOOKS TO BE SLOW TO PUSH SE FROM KY (AND WEAKENS WHILE
DOING SO). STILL ENOUGH RESIDUAL LOW/MID LEVEL MOISTURE AND
SCATTERED SHRA/TSTMS ONGOING IN NC/WESTERN VA TO KEEP CHC POPS
GOING OVERNIGHT. LITTLE MOVEMENT EXPECTED WITH THE SFC BOUNDARY
AND DUE TO FAIRLY WEAK MID/UPPER DYNAMICS DO NOT EXPECT THE
AMOUNT OF COVERAGE OR INTENSITY AS LAST NIGHT. CONCERNING
TSTMS...WILL KEEP MENTION OF ISOLATED CONVECTION OVER FAR SOUTHERN
VA/NE NC GOING AFTER MIDNIGHT WHERE ML CAPE ON THE ORDER OF 500 TO
1000 J/KG PERSISTS (JUST SHRA FARTHER NORTH). MIN TEMPS DROP VERY
LITTLE FROM CURRENT VALUES WITH MAINLY OVC SKIES AND MIXING...LOW
TO MID 60S FOR MOST LOCATIONS.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
WET WEATHER WILL CONTINUE SUNDAY THROUGH MONDAY AS THE STALLED FRONT
BEGINS TO LIFT NWD. ALSO AN UPPER LEVEL TROUGH OVER THE OH/KY AREA
WILL MOVE ACROSS THE MID ATLANTIC REGION MONDAY. PCPN IS EXPECTED TO
BE MOST WIDESPREAD OVER WESTERN PORTIONS OF THE AREA SUNDAY PER
MODEL GUIDANCE WHERE UPPER LEVEL SUPPORT WILL BE BEST. POPS INCREASE
ONCE AGAIN MONDAY MAINLY ACROSS SRN PORTIONS. AS THE TROUGH MOVES
OFF TO THE EAST...PCPN DECREASES OVER WRN PORTIONS BY MONDAY AFTN.

HIGH TEMPERATURES SUNDAY AND MONDAY WILL BE WARMER...GENERALLY IN
THE UPR 70S TO LWR 80S WITH SLIGHTLY COOLER READINGS NEAR THE COAST.
LOWS WILL RANGE THROUGH THE 60S.

DURING THE REMAINDER OF THE SHORT TERM...WHILE THE UPPER LEVEL
TROUGH MOVES OFF TO THE EAST...FURTHER UPPER LEVEL IMPULSES ARE
EXPECTED TO IMPACT THE AREA. PCPN DIMINISHES BY AROUND MIDNIGHT
MONDAY NIGHT. SOME REDEVELOPMENT OF TSTMS IS EXPECTED TUESDAY AFTN
MAINLY OVER SRN VA/NE NORTH CAROLINA. HIGH TEMPERATURES TUESDAY ARE
FORECAST TO REACH INTO THE MID TO UPR 80S AT MOST LOCATIONS.

72 HR QPF TOTALS FORECAST TO RANGE FROM 1 TO 2 INCHES WITH
LOCAL AMOUNTS TO 3 INCHES POSSIBLE ACROSS THE PIEDMONT TO AROUND
A HALF INCH TO AN INCH TOWARD THE COAST. SOME ISSUES ON AREA
RIVERS ARE PSBL EARLY THIS COMING WEEK. SEE HYDRO SECTION BELOW.
AT THIS TIME...THERE ARE NO PLANS FOR A FLOOD WATCH BUT THIS WILL
CONTINUE TO BE MONITORED.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
MODELS SIMILAR OVER THIS TIME PERIOD WITH THE TIMING OF ANOTHER TROF
DEEPING AT 500 MB TOWARD FRIDAY AND SATURDAY. THIS WILL USHER A
STRONGER COLD FRONT THROUGH THE REGION FRIDAY INTO SATURDAY. THE
FRONT WILL HAVE SOME SHOWERS AND THUNDERSTORMS WITH IT AS IT MOVES
THROUGH. BEFORE THAT A FRONTAL BOUNDARY REMAINS NEARLY STATIONARY
ACROSS THE GREAT LAKES AND NEW ENGLAND. SOUTH OF THIS AREA WILL HAVE
GENERAL SOUTH TO SOUTHWEST FLOW ACROSS THE AREA. COULD SEE AN
ISOLATED AFTERNOON THUNDERSTORM. ANY THUNDERSTORMS THAT FORM NORTH
ALONG THE BOUNDARY COULD PUSH INTO THE NORTHERN PART OF THE AREA
DURING THE EVENINGS. TEMPERATURES WILL BE AT OR ABOVE NORMAL UNTIL
THE FRONT PASSES. THEN TEMPERATURES WILL DROP BACK ON SATURDAY TO AT
OR BELOW NORMAL.

&&

.AVIATION /23Z SATURDAY THROUGH THURSDAY/...
TRICKY AVIATION FORECAST THIS AFTERNOON THROUGH SUNDAY. SHOWERS
FROM RIC TO SBY WERE SLOWLY PUSHING EAST AND SHOULD MAKE THEIR WAY
TO PHF AROUND 19-20Z. EVEN WITH THE SHOWERS CONDITIONS AT RIC WERE
MVFR AS OF 1730Z AND SHOULD REMAIN MVFR WITH A BRIEF PERIOD OF IFR
THROUGH 22Z AS PERIODS OF RAIN REDUCE VSBYS TO JUST BELOW 3SM AND
THE NE FLOW DROPS CEILINGS TO JUST LESS THAN 1KFT. AT SBY
PREVAILING IFR CONDITIONS SHOULD HOLD OFF UNTIL AROUND 06Z WHEN
SE WINDS INCREASE AND STRATUS MOVES IN FROM THE OCEAN. THE SHOWERS
NEAR RIC TO PTB SHOULD REACH PHF SHORTLY AFTER 20Z AND MVFR
CONDITIONS AT PFH COULD BECOME BRIEFLY IFR WITH A FEW HEAVER
SHOWERS THROUGH 23Z. ONCE THE COVERAGE IN SHOWER ACTIVITY
DECREASES WITH SUNSET MVFR CONDITIONS WILL PREVAIL AT PHF.

MORE SHOWERS WERE ONGOING FROM NEAR ECG WEST ALONG THE NC/VA
BORDER ALONG ANOTHER BOUNDARY. THIS AREA OF SHOWERS MAY EXPAND
BRIEFLY BUT THE BULK OF THE RAIN MAY STAY WEST OF ORF AND ECG THIS
AFTN AND EVENING. A BRIEF PERIOD OF SHOWERS MAY REACH ORF FROM
21Z-02Z BUT SHOWER ACTIVITY SHOULD BE VERY SCATTERED AS FAR EAST
AS ORF AND PHF. OVERALL CONDITIONS AT ORF AND PHF SHOULD REMAIN
MVFR WITH A BRIEF PERIOD OF IFR POSSIBLE IN THE SHOWERS.

GUIDANCE SUGGESTS RIC WILL BECOME IFR WITH STRATUS OVERNIGHT ALONG
WITH SBY AND REMAIN IFR THROUGH MID MORNING SUNDAY. CLOSER TO THE
COAST THE REMAINDER OF THE TAF SITES REMAIN MVFR OVERNIGHT. FOR
SUNDAY EXPECT MUCH OF THE SAME WITH MVFR-VFR CONDITIONS OVER SE VA
AND NE NC AND MVFR-IFR CONDITIONS AT RIC AND SBY.

&&

.MARINE...
DIFFICULT FORECAST INITIALLY TO SEE IF WE GET TO SMALL CRAFT
CONDITIONS ON THE BAY. ALL HIGH RES MODELS WOULD SUPPORT A PERIOD OF
SMALL CRAFT WINDS INTO THIS EVENING. SEEING WINDS STAYING CLOSE BUT
JUST UNDER SMALL CRAFT AT 19Z. EXPECT THAT BY 20Z MOST SITES WILL
HAVE SMALL CRAFT CONDITIONS. THIS WIND INCREASE SEEMS TO BE
ASSOCIATED WITH A WEAK LOW PRESSURE MOVING ALONG THE BOUNDARY SOUTH
OF THE AREA INCREASING THE SOUTHEAST WINDS. WITH CONTINUED EAST TO
SOUTHEAST WINDS TONIGHT WILL SEE SEAS INCREASE TO 5 FEET ALONG THE
NORTHERN COASTAL WATERS. SEAS WILL DROP BACK TO UNDER 5 FEET ON
SUNDAY. WINDS WILL ALSO DIMINISH AND GRADUALLY BECOME MORE SOUTHERLY
ON SUNDAY AND THEN SOUTHWEST ON MONDAY AS A WARM FRONT MOVES SLOWLY
NORTH THROUGH THE WATERS. THE WARM FRONT WILL SLOWLY LIFT NORTH FROM
NORTH CAROLINA TONIGHT AND SUNDAY AND FINALLY BE NORTH OF THE WATERS
ON MONDAY A WEAK UPPER LOW WILL MOVE SLOWLY EAST FROM THE MIDWEST
AND EVENTUALLY OFF THE COAST BY MONDAY NIGHT. THESE FEATURES WILL
CONTINUE SHOWERS AND THUNDERSTORMS AT TIMES THROUGH MONDAY.

&&

.HYDROLOGY...
RAINFALL OVER THE PIEDMONT AND RIDGES TO THE WEST ARE FORECAST TO
BRING SIGNIFICANT RISES TO AREA RIVERS BY MONDAY AND TUESDAY. SOME
LOCATIONS WILL LIKELY EXPERIENCE ACTION STAGE AND MAY POSSIBLY
HAVE MINOR FLOODING. THIS WILL DEPEND ON WHICH BASINS LOCALLY
HEAVY RAINFALL SETS UP WHICH IS TOO EARLY TO DETERMINE.

&&

.EQUIPMENT...
AKQ 88D RADAR IS BACK IN SERVICE.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR ANZ630>632-
     634-638.
     SMALL CRAFT ADVISORY UNTIL 6 AM EDT SUNDAY FOR ANZ650-652-654.

&&

$$
SYNOPSIS...LKB
NEAR TERM...LKB/LSA
SHORT TERM...LSA
LONG TERM...JAB
AVIATION...JAO
MARINE...JAB
HYDROLOGY...AKQ
EQUIPMENT...AKQ