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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KLWX 170750
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
350 AM EDT MON JUN 17 2013

.SYNOPSIS...

-- Changed Discussion --
A WEAK COLD FRONT APPROACHING FROM THE NORTH ON MONDAY WILL STALL OVER
THE MID ATLANTIC THROUGH TUESDAY...THEN MOVE SOUTH OF THE REGION
EARLY WEDNESDAY. AN AREA OF LOW PRESSURE WILL TRACK SOUTH OF THE
AREA TUESDAY NIGHT. HIGH PRESSURE WILL RETURN FOR THE REMAINDER OF
THE WEEK.
-- End Changed Discussion --

&&

.NEAR TERM /TODAY/...

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AS OF 07Z...THE MAIN (BUT WEAK) SFC TROUGH IS DEPICTED BEST BY
REGIONAL RADAR MOSAIC AS SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS ALONG THE SRN LWX CWA BORDER STRETCHING FROM SWRN VA
TO THE SRN DELMARVA. ANOTHER SFC TROUGH HAS BEEN PUSHING SOUTHEAST
FROM LAKE ERIE AS INDICATED BY A SCATTERED LINE OF SHOWERS OVER NERN
OH AND NWRN PA. A WLY COMPONENT IN BETWEEN THESE TROUGHS HAS AIDED
SCATTERED UPSLOPE SHOWERS IN THE LAURELS OF PA AND THE NORTHERN
POTOMAC HIGHLANDS. OTW...IR IMAGERY INDICATES MID AND HIGH CLOUDS
ACROSS THE REST OF THE LWX CWA.

TODAY...THE SFC TROUGHS PROVIDE MAIN FOCUS OF DEVELOPMENT TODAY. 00Z
GUIDANCE INCHES THE SRN TROUGH NORTH TO BRING SCATTERED ACTIVITY (40
TO 50 POP) TO THE SRN THIRD OF THE CWA BY THE AFTERNOON. ACCORDING
TO THE 05Z HRRR...THE NRN TROUGH DIPS SOUTH OF THE MASON-DIXON LINE
THROUGH THE MID-MORNING HOURS WITH SCATTERED MIDDAY/AFTERNOON
THUNDERSTORMS ACROSS THE BALT-WASH METRO AND WEST TO THE POTOMAC
HIGHLANDS. NO INDICATION THAT ANY ACTIVITY WILL BE GREATER THAN
GENERAL VARIETY. SIMILAR MAX TEMPS TO SUNDAY WITH CONTINUED MID
LEVEL CLOUDS AND 850MB TEMPS NEAR 15C AGAIN.
-- End Changed Discussion --

&&

.SHORT TERM /TONIGHT/...

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SFC TROUGHS DRIFT SOUTH OF THE CWA AND BECOME EVEN MORE
DIFFUSE. LITTLE FORCING EXPECTED TONIGHT...SO POPS WERE DECREASED
FOR THE EVENING AND REMOVED FOR MOST OF THE AREA LATE TONIGHT.
CLEARING WITH SLIGHTLY DRIER AIR WILL MAKE FOR A COOLER NIGHT...LOW
60S SHEN VLY AND WEST...MID 60S PIEDMONT...NEAR 70F FOR URBAN
CENTERS AND NEAR SHORE.
-- End Changed Discussion --

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...

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I DID A BRIEF LOOK AT THE LAST COUPLE OF JUNES TO CHECK ON TEMPS.
IN DC IN 2012 THE 2ND HALF OF OF THE MONTH...BTWN THE 20TH AND
24TH THE HIGHS WERE 98..99..97..91 AND 93. AND THE LAST 3 DAYS OF
THE MONTH HAD HIGHS OF 96..104 AND 97. IN 2011 THERE WAS A READING
OF 102 ON THE 9TH. THE WARMEST DC HAS BEEN SO FAR THIS JUNE WAS 91
ON THE 1ST AND 12TH. IN THE XTND TUE LOOKS LK THE WARMEST DAY OF
THE WORKWK - A90. ISOLD TSTMS PSL TUE..BUT UNLK LAST WK (BIG SVR
DAYS ON MON AND THU) THE SVR THREAT LOOKS MUCH LOWER THIS WK.

A WEAK AREA OF LOW PRES IS XPCTD TO TRACK S OF THE AREA TUE NGT.
WE`RE MOVG INTO THE TIME OF YR WHEN IT IS GETTING RARE TO HV RAFL
LAST FOR LENGTHY PDS PDS OF TIME FM MID LAT CYCLONES. THIS LOW
DOES NOT APPEAR TO BE STRONG...BUT WL TRIGGER RW/ISOLD CNVTCN.
THIS IS XPCTD TO MOVE OFFSHORE WED MRNG AND BRING AN END TO THE
PCPN CHCS.

HIGH PRES TO MOVE OVR THE NERN U.S. FOR THE 2ND HALF OF THE
WORKWK. HIGHS XPCTD TO BE IN THE M80S WED THRU FRI. HIGH MOVES
OFF THE CST FOR THE WKND...BRINGING A RETURN TO HIGHER HUMIDITY W/
HIGHS IN THE MU80S.
-- End Changed Discussion --


&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...

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VFR PREVAILS TODAY WITH (AT BEST) SCATTERED SHOWER AND THUNDERSTORM
ACTIVITY MID MORNING THROUGH THE AFTERNOON ACROSS THE TERMINALS.
LIGHTER SWLY FLOW TODAY...AOB 10KT. WEAK TO CALM FLOW TONIGHT.

VFR CONDS XPCTD THE MAJORITY OF THE XTND PD. LOW CHANCES OF
AFTERNOON/EVENING THUNDERSTORMS TUESDAY UNTIL TRACKS SE OF THE
AREA WEDNESDAY. HIGH PRES OVR THE AREA WED THRU FRI.
-- End Changed Discussion --

&&

.MARINE...

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SWLY FLOW AROUND 10 KT ACROSS THE WATERS TODAY...BECOMES SLY THIS
EVENING WITH CHANNELING ON MAIN STEM TO 15 KT.

WINDS XPCTD TO RMN BLO DURG THE WK AHD. ISOLD TSTMS ON TUE/TUE NGT THE
BIGGEST THREAT TO MARINERS.
-- End Changed Discussion --

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.

&&

$$
PRODUCTS...BAJ/WOODY!