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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KAKQ 150130
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
930 PM EDT TUE MAY 14 2013

.SYNOPSIS...
A WARM FRONT LIFTS THROUGH THE MID ATLANTIC LATE TONIGHT INTO EARLY
WEDNESDAY. THIS WILL BRING MUCH WARMER TEMPERATURES TO THE REGION AS
HIGH PRESSURE SETTLES OFF THE SOUTHEAST COAST THROUGH THE END OF THE
WEEK. A WEAK FRONT APPROACHES THE AREA FROM THE NORTH THURSDAY
AFTERNOON AND SLOWLY SETTLES INTO THE ARE THROUGH FRIDAY.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
THE LATEST SURFACE ANALYSIS INDICATES A 1025MB SURFACE HIGH CENTERED
OVER THE NORTHERN GULF OF MEXICO, WITH A SURFACE RIDGE AXIS
EXTENDING NE JUST OFF THE CAROLINA COAST. ALOFT...A PROGRESSIVE
LONGWAVE PATTERN IS DEVELOPING AS THE COLD TROUGH OF THE PAST FEW
DAYS MOVES OFF THE COAST...AND A STRONG RIDGE OVER THE CENTRAL US
EXPANDS EASTWARD. THIS WILL PRODUCE SUBSTANTIAL WARMING ALOFT IN
THE THERMAL PROFILE...BUT ESPECIALLY ABOVE 800MB...WHICH SHOULD
RESULT IN CONSIDERABLE MID AND HIGH CLOUDS OVERNIGHT. AT THE
SURFACE...A WARM FRONT BEGINS TO LIFT SW-NE ACROSS THE AREA LATE
TONIGHT. A WEAK SHORTWAVE TROUGH TRACKING NW-SE IN NNW FLOW ALOFT
OVERNIGHT ALONG WITH WAA HAS ALREADY TRIGGERED A FEW SPRINKLES
ALONG THE MASON DIXON LINE FROM HAGERSTOWN TO THE UPPER EASTERN
SHORE OF MARYLAND, AND A SLIGHT CHC POP HAS BEEN RETAINED FOR A
FEW SCT SHOWERS OVER THE LOWER MD EASTERN SHORE OVERNIGHT (QPF
GENERALLY A TRACE TO A FEW HUNDREDTHS). LOW TEMPERATURES WILL BE
MUCH MILDER IN THIS QUICKLY MODIFYING AIRMASS, WITH EARLY MORNING
LOWS TO RANGE FROM THE UPPER 40S TO LOW 50S...UNDER A PARTLY TO
MOSTLY CLOUDY SKY.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
THE WARM FRONT LIFTS THROUGH THE REGION WEDNESDAY MORNING WITH A W-E
CLEARING TREND. ANY LINGERING SHOWERS OVER THE EASTERN SHORE SHOULD
EXIT THE REGION EARLY. TEMPERATURES WILL SOAR ABOVE NORMAL WEDNESDAY
AS THE MID-LEVEL RIDGE BUILDS OVER THE REGION WITH HIGHS RISING
NEARLY 20F OVER THOSE OF TODAY...WITH THE EXCEPTION OF THE IMMEDIATE
COAST. MID-LEVEL LAPSE RATES ARE PROGGED TO STEEPEN LATER WEDNESDAY
AFTERNOON INTO WEDNESDAY EVENING. FORECAST SOUNDINGS INDICATE A
DECENT AMOUNT OF INSTABILITY ALBEIT ABOVE A RATHER STRONG CAP. THE
BEST FOCUS FOR ANY CONVECTION WILL BE N OF THE LOCAL AREA (ACROSS
PA) AS A WEAK FRONT DROPS DOWN FROM THE N. HOWEVER...SOME OF THE
COULD CLIP THE FAR NE LATER WEDNESDAY AFTERNOON INTO WEDNESDAY
EVENING...SO A SLIGHT CHANCE/LOW CHANCE OF THUNDER WILL BE
MAINTAINED.

THE AFOREMENTIONED BOUNDARY DROPS INTO THE AREA THURSDAY PROVIDING
AN INCREASED FOCUS FOR AFTERNOON AND EVENING THUNDER. OVERALL
FORCING IS RATHER WEAK...SO ANY STORMS SHOULD BE RATHER DISORGANIZED
AND HENCE WILL FORECAST NO HIGHER THAN A 40 POP. SIMILAR CONDITIONS
ARE EXPECTED FRIDAY WITH THE PRIMARY FOCUS FOR CONVECTION SHIFTING S
AS A WEAK HIGH PUSHES INTO THE NE CORNER OF THE AREA. HIGHS THURSDAY
SHOULD BE IN THE IN THE LOW TO MID 80S (AWAY FROM THE ATLANTIC
COAST) AND LOWER A FEW DEGREES TO 80-85 FRIDAY. LOWS SHOULD LARGELY
BE IN THE UPPER 50S TO MID 60S.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
STILL SOME UNCERTAINTY THROUGHOUT THE EXTENDED PERIODS REGARDING
SMALLER SCALE FEATURES...HOWEVER THE OVERALL MESSAGE REMAINS THE
SAME. SFC HIGH PRESSURE AND UPPER LEVEL RIDGING DOMINATE THE WEATHER
PATTERN WITH WARM AIR ADVECTING IN THE REGION FROM THE SW.

IN REGARD TO TEMPERATURES...SATURDAY APPEARS TO BE THE COOLEST DAY
IN THE LONG RANGE FORECAST AS AN UPPER LEVEL TROUGH CROSSES NRN NEW
ENGLAND AND HIGH PRESSURE AT THE SFC BRINGS A BRIEF COOL DOWN TO THE
REGION. SAT HIGHS IN THE LOWER 80S...LOW-MID 70S ALONG THE IMMEDIATE
COAST DUE TO PERSISTENT ONSHORE/ELY FLOW. TEMPERATURES ARE EXPECTED
TO SLOWLY REBOUND BY A FEW DEGREES EACH DAY FROM SUN INTO EARLY NEXT
WEEK AS THE UPPER LEVEL RIDGE MOVES OVER THE ERN SEABOARD. HIGHS
GENERALLY IN THE LOW-MID 80S (MID-UPPER 70S IMMEDIATE COAST) WITH
LOWS SAT-MON GENERALLY IN THE LOW-MID 60S.

IN REGARD TO PRECIPITATION...VARIOUS SHORTWAVES/MOISTURE PASSING
THROUGH W-NW FLOW ALOFT...IN ADDITION TO DIFFERING LONG RANGE MODEL
SOLUTIONS...WILL MAKE IT DIFFICULT TO NAIL DOWN EXACT TIMING OF
POTENTIAL SHOWERS AND THUNDERSTORMS. WILL THEREFORE CARRY A CHANCE
FOR AFTN/EVENING THUNDERSTORMS WITH LIGHT RAIN SHOWERS DURING THE
OVERNIGHT AND MORNING TIMEFRAMES FOR FRI NIGHT THROUGH MON.

&&

.AVIATION /02Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
MID LEVEL WAA CLOUDINESS WILL PASS OVER THE AREA IN NW FLOW THROUGH
WEDNESDAY MORNING. AS A WARM FRONT PASS TO THE EAST OF THE
REGION...THIS CLOUDINESS WILL SCATTER OUT. WINDS WILL BECOME GUSTY
FROM THE SOUTHWEST ON WEDNESDAY. RADAR RETURNS OVER THE MD EASTERN
SHORE ARE NOT EXPECTED TO PRODUCE ANY SIGNIFICANT PCPN DUE TO DRY
AIR IN THE LOW LEVELS.

OUTLOOK...MAINLY VFR CONDITIONS ARE EXPECTED THROUGH THE WEEKEND.
SCATTERED SHOWERS AND THUNDERSTORMS FROM TIME TO TIME...ESPECIALLY
IN THE AFTN AND EVENING WHICH MAY BRIEFLY LOWER AVIATION CONDITIONS.
ALSO PATCHY FOG NEAR SUNRISE WILL BE PSBL BY THE WEEKEND.
-- End Changed Discussion --

&&

.MARINE...
-- Changed Discussion --
RAISED SCA FOR THE BAY AS WINDS ARE EXPECTED TO INCREASE TO BETWEEN
15 AND 20 KNOTS PER MOST MODELS. ALSO SURFACE TRANS WINDS PER NAM
INDICATE WINDS REACHING 20 KNOTS OVERNIGHT. SEAS ARE NOT EXPECTED TO
INCREASE IN THE COASTAL WATERS TNGT AND WEDNESDAY AS MUCH AS WAVE
WATCH AND SWAN AS THESE HAVE BEEN SHOWN TO OVERDUE THE SEAS DURING
SHORT LIVED SOUTHERLY FLOW EVENTS.

CURRENT FORECASTS HAVE WINDS IN MUCH OF OUR WATERS RUNNING 15 TO 20
KNOTS ON WEDNESDAY. AS AIR TEMPERATURES WARM SIGNIFICANTLY HIGHER
THAN WATER TEMPERATURES...THESE WINDS MAY REMAIN ELEVEATED AND OUR
FORECAST WINDS MAY NEED TO BE LOWERED A BIT BY THE MID SHIFT.
THEREFORE...THE SCA FOR THE BAY FOR NOW EXPIRES AT 14Z WEDNESDAY.

PREVIOUS DISCUSSION...
HI PRES SLIDES INTO THE ATLC TNGT...AND A WEAK WARM FRONT WILL MOVE
ACRS THE AREA LATE TNGT INTO WED MORNG. W OR VRBL WNDS 10 KT OR LESS
THIS EVENG...WILL BECOME S AND INCREASE TO 15 TO 20 KT LATER THIS
EVENG INTO WED MORNG. SSW WINDS 15 TO 20 KT WILL CONTINUE WED INTO
WED NGT...AS WARM FRONT LIFTS ENE OF THE REGION AND PRES GRADIENT
TIGHTENS A BIT MORE. WAVES 1 TO 3 FT...WITH SEAS 2 TO 4 FT. SEAS
COULD GET TO 5 OR 6 FT OVR THE NRN CSTL WTRS WED EVENG/NGT...BUT FOR
NOW DID NOT ISSUE A SCA. WINDS BECOME WNW AND WEAKEN WED NGT...THEN
BECOME VRBL THU AFTN. A WEAK FRONT WILL THEN DROP ACRS THE AREA LATE
THU INTO FRI MORNG...WITH WINDS SHIFTING FM SW TO THE N OR NE ARND
10 KT OR LESS.
-- End Changed Discussion --

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 AM EDT WEDNESDAY FOR ANZ630>632-
     634.

&&

$$
SYNOPSIS...AJZ
NEAR TERM...AJZ/MAM
SHORT TERM...AJZ
LONG TERM...BMD
AVIATION...LSA
MARINE...TMG/LSA