AP-NC--BWI-NC Area Forecast Discussion, NC

000

FXUS61 KLWX 151324

AFDLWX

AREA FORECAST DISCUSSION

NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC

924 AM EDT WED JUL 15 2015

.SYNOPSIS...

HIGH PRESSURE WILL BUILD FROM THE NORTH TONIGHT THROUGH

THURSDAY...AND CONTINUE IN THE AREA UNTIL FRIDAY. AN UNSETTLED

PATTERN RETURNS BY THE WEEKEND AS THE HIGH SHIFT OFFSHORE. ANOTHER

COLD FRONT WILL APPROACH EARLY NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...

TWO AREAS OF LIGHT PRECIP ARE ATTEMPTING TO SPREAD INTO THE AREA

THIS MORNING. THE FIRST IS WRAPAROUND FROM THE UPPER

TROUGH...TRYING TO SNEAK INTO NERN MD. THE SECOND IS ACTIVITY WEST

OF THE DIVIDE WHICH SO FAR HAS NOT MADE IT INTO THE REGION.

OTHERWISE...PLENTY OF CLOUD COVER IS SPREADING INTO THE REGION

FROM THE NORTH. THIS CLOUD COVER MAY SERVE AS A LIMITING FACTOR

FOR ADDITIONAL DEVELOPMENT THIS AFTERNOON WEST OF THE METRO

CORRIDOR.

TWEAKED POPS BASED ON CURRENT TRENDS AND FOCUSED THEM LARGELY

WHERE THE 4KM NAM /WHICH SEEMS TO HAVE A GOOD HANDLE/ IS SHOWING

THE BEST PROBABILITY OF ACTIVITY TODAY. ALSO TWEAKED HIGHS DOWN

JUST A BIT OVER THE NORTHERN COUNTIES DUE TO THE INCREASED CLOUD

COVER. OTHERWISE...FORECAST LOOKS ON TRACK.

DEWPTS BEGIN TO DROP LATE THIS AFTERNOON...AND WINDS WL PICK UP.

THE ADVCTN AND SUBSIDENCE SHUD DRY OUT AMS. WL BE SCALING BACK

POPS AT THAT TIME.

WOULD LIKE TO KEEP TNGT DRY THRUT...BUT CANNOT BE CERTAIN WHETHER

THERE WL BE A STRAY SHRA ALONG THE BAY AT START OF PD /6PM/. AM

THEREFORE KEEPING A CPL HRS OF 20-30 PCT POPS. HWVR...CLDS WL

RAPIDLY DIMINISH AFTER THAT.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY/...

RDGG WL IMPACT CWFA THU-FRI PROVIDING A RESPITE FROM THE WET PD

WE/VE BEEN EXPERIENCING. THE RDG WL BE SLIDING EWD LT FRI. SOME GDNC

SUGGESTING THERE MAY BE A FEW MTN SHRA/TSRA IN THE AFTN. HV KEPT

FCST DRY AT THIS POINT.

LOW MEAN LYR RH SUGGESTS THAT SKIES WL BE MOSUN DURING THE DAY AND

MOCLR AT NGT. SUSPECT THERE WL BE SOME MID DECK ON FRI IN THE

RETURN FLOW IN ADDITION TO DIURNAL CU. BELIEVE THAT CU DVLPMNT WL BE

MORE PRONOUNCED IN THE MTNS.

THU WL BE THE COOLEST DAY OF THIS STRETCH...W/ TEMPS ONLY IN THE LWR

80S. COMBINE THAT WITH DEWPTS ONLY IN THE 50S. THAT WL MAKE FOR

ANOTHER COOL NIGHT THU NGT BEFORE TEMPS REBOUND ON FRI. TEMPS DURING

THE END OF THE WEEK WL REMAIN BELOW AVG.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...

SYNOPTIC PATTERN DURING THE LONG TERM CAN BE CHARACTERIZED BY BROAD

RIDGING THROUGH THE CENTRAL PART OF THE US...LEAVING US IN A NWLY OR

WLY FLOW ALOFT. INITIALLY...RIDGE AXIS WILL BE CENTERED OVER THE SE

STATES SAT AND SUN...WHICH WILL INCREASE TEMPERATURES OVER THE

REGION...WITH TEMPERATURES RETURNING TO THE L90S. DEWPOINTS WILL

ALSO BE IN THE L70S...SO HEAT INDICES OVER THE WEEKEND COULD TOP THE

CENTURY MARK.

BY THE BEGINNING OF THE WEEK...RIDGE AXIS RETROGRADES TO THE

WEST...WHICH ALLOWS MORE NWLY FLOW TO DEVELOP...AND HELPS TO TRACK

PIECES OF UPPER-LEVEL ENERGY AND AN ASSOCIATED COLD FRONT NEAR OUR

CWA. CONSEQUENTLY...TEMPS SHOULD DROP BACK DOWN TO IN THE

U80S...CLOSER TO CLIMO NORMS BY TUES.

PRECIP CHANCES DURING THE LONG TERM ARE MORE UNCERTAIN. WHILE THERE

ARE CHANCES NEARLY EACH DAY...FOCUS FOR DEVELOPMENT IS NOT VERY

CLEAR AT THIS POINT...AND WILL LARGELY BE TIED TO MESOSCALE FEATURES

THAT ARE UNRESOLVABLE AT THIS TIME SCALE. PERHAPS THE GREATEST

CHANCE FOR WIDESPREAD COVERAGE WOULD COME SOMETIME TUESDAY WITH COLD

FRONTAL PASSAGE.

&&

.AVIATION /13Z WEDNESDAY THROUGH SUNDAY/...

VFR CONDS EXPCT FOR VALID TAF PD. AM XPCTG CU DVLPMNT BY MID MRNG

/BASES 040/...WHICH WL LAST THRU MID TO MAYBE LT AFTN. THERE SHUD

BE SCTD SHRA AND A CPL TSRA. BEST CVRG DURING ELY AFTN BEFORE

DRIER AIR SPREADS EAST. HV SHRA MENTIONED BUT WL NOT BE CARRYING

ANY TSRA OR RESTRICTIONS AT THIS PT.

NW WINDS G20KT ELY THIS EVNG WL DIMINISH OVNGT. OTRW VFR THRU FRI.

MAIN AVIATION CONCERN OVER THE WEEKEND IS CHCS FOR SCATTERED

THUNDERSTORMS EACH DAY...WITH SUB-VFR POSSIBLE NEAR ANY ACTIVITY.

VFR CONDS EXPECTED OUTSIDE OF SHOWERS/THUNDERSTORMS.

&&

.MARINE...

WINDS ARE ALREADY GUSTING TO SCA LEVEL IN THE SOUTHERN BAY...AND

STARTING TO SEE GUSTS AROUND 18 KTS ELSEWHERE ALSO. EARLIER...

EXPANDED THE TIME OF THE SCA IN THE SOUTHERN BAY TO START

IMMEDIATELY...AND MAY NEED TO DO THE SAME FOR THE REST OF THE

WATERS SHORTLY BASED ON CURRENT TRENDS.

ADVY CONTS OVNGT FOR THE BAY/LWR TRIBS...AND HV CARRIED THAT INTO

THU BEFORE THE P-GRAD WEAKENS.

WINDS SHOULD REMAIN JUST BELOW SCA CRITERIA OVER THE WEEKEND.

SCATTERED AFTERNOON THUNDERSTORMS ARE POSSIBLE SATURDAY AND

SUNDAY...SO MARINERS SHOULD MONITOR FOR ANY ACTIVITY WHICH COULD

LEAD TO GUSTY WINDS ON THE WATER.

&&

.TIDES/COASTAL FLOODING...

NORTHWEST FLOW IS NOW COMMENCING...AND THE TIDAL FLOOD THREAT IS

OVER.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...

DC...NONE.

MD...NONE.

VA...NONE.

WV...NONE.

MARINE...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO NOON EDT

THURSDAY FOR ANZ530>533-537>542.

SMALL CRAFT ADVISORY UNTIL NOON EDT THURSDAY FOR ANZ534-543.

SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO MIDNIGHT EDT

TONIGHT FOR ANZ535-536.

&&

$$

SYNOPSIS...HTS

NEAR TERM...JE/HTS

SHORT TERM...HTS

LONG TERM...MSE

AVIATION...JE/MSE/HTS

MARINE...JE/MSE/HTS

TIDES/COASTAL FLOODING...JE

Delivered by Weather Underground Inc. Wed Jul 15 2015 9:25AM EDT