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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KLWX 161414 AAA
AFDLWX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1014 AM EDT THU MAY 16 2013

.SYNOPSIS...
A COLD FRONT WILL SAG SOUTHWARD ACROSS THE AREA TODAY. THE FRONT
WILL STALL JUST SOUTH OF THE REGION THROUGH THE WEEKEND WHILE HIGH
PRESSURE BUILDS TO THE NORTH IN NEW ENGLAND. THE STALLED FRONTAL
BOUNDARY WILL LIFT NORTHWARD ACROSS THE REGION AS A WARM FRONT
EARLY NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
CONVECTIVE POTENTIAL TODAY WILL BE FOCUSED ALONG AND NORTH OF THE
SOUTHWARD SAGGING FRONTAL BOUNDARY. FOCUS THE NEXT FEW HOURS WILL
CONTINUE OVER NORTHERN MD AND THE POTOMAC HIGHLANDS. WEAK
VORTMAX/UPPER DISTURBANCES RIDING ALONG THE BOUNDARY WILL HEP KEEP
CONVECTIVE CHANCES GOING INTO THIS AFTERNOON AND EVENING WITH
FOCUS SHIFTING FURTHER SOUTH ACROSS VIRGINIA. WILL CONTINUE TO
FOCUS HIGHEST POPS WEST OF THE METRO AREAS AND BLUE RIDGE.
ATMOSPHERE IS CERTAINLY MORE MOIST TODAY THAN YESTERDAY AT THIS
TIME. BRIEF DOWNPOURS A POSSIBILITY WITH STORMS TODAY. ANY BREAKS
IN THE CLOUD COVER WILL HELP TEMPERATURES RISE INTO THE 80S THIS
AFTERNOON. BUFKIT AND NAM/GFS SOUNDING PROGS AT KIAD SHOW DECENT
CAPE YET LOW SHEAR ENVIRONMENT BUT LITTLE FORCING OTHER THAN
SAGGING SURFACE BOUNDARY. WHILE AN ISOLATED STRONG STORM IS
POSSIBLE...WE ARE NOT EXPECTING ANY KIND OF ORGANIZED SEVERE
THREAT GIVEN THE PATTERN SETUP TODAY.

FOCUS FOR SHOWERS SHIFTS TO THE SOUTHERN PORTION OF THE CWFA
TONIGHT. LOWS EXPECTED IN THE 50S-60S.
-- End Changed Discussion --

&&

.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
FRONTAL BOUNDARY IS FORECAST TO STALL OUT TO THE SOUTH OF THE
AREA FRIDAY INTO THE WEEKEND AS HIGH PRESSURE BUILDS TO THE NORTH
ACROSS EASTERN CANADA AND NEW ENGLAND.

ON FRIDAY HAVE FOCUSED POPS/THUNDERSTORM POTENTIAL ACROSS THE
SOUTHWEST PORTION OF THE CWA CLOSEST TO THE BOUNDARY WITH A DRY
FORECAST FURTHER NORTHEAST TOWARD THE DC-BALT METRO AREA.

HOWEVER OVER THE WEEKEND...EVEN WITH THE BOUNDARY TO THE SOUTH
MODELS INDICATE SIGNS OF LIFT INCREASING TO THE NORTH LIKELY DUE TO
VORT MAXES/SHORTWAVES IN 500 MB FLOW IN TANDEM WITH LOW LEVEL
EASTERLY FLOW. THEREFORE POPS EXPAND NORTHEASTWARD DURING THE
WEEKEND.

AT THE SURFACE...AFOREMENTIONED EASTERLY LOW LEVEL FLOW IS EXPECTED
TO TREND MAXIMA DOWNWARD TO BELOW NORMAL OVER THE WEEKEND WITH NEAR
TO SLIGHTLY ABOVE NORMAL MINIMA.

&&

.LONG TERM /MONDAY THROUGH WEDNESDAY/...
FRONTAL BOUNDARY WILL LIFT BACK TO THE NORTH AS A WARM FRONT EARLY
NEXT WEEK...ALLOWING TEMPERATURES TO TREND UPWARD THROUGH MID-WEEK
IN ADVANCE OF THE NEXT LARGER SCALE SHORTWAVE. UNSETTLED CONDITIONS
WITH A CHANCE OF CONVECTION IS EXPECTED THROUGH THEN.

&&

.AVIATION /14Z THURSDAY THROUGH MONDAY/...
-- Changed Discussion --
SHOWERS AND ISOLATED THUNDERSTORMS POSSIBLE ALONG AND NORTH OF A
SOUTHWARD SAGGING FRONTAL BOUNDARY. HIGHEST FOCUS OVER NORTHERN
MARYLAND AND POTOMAC HIGHLANDS INITIALLY...SHIFTING SOUTH LATER
TODAY. MOST TERMINALS WILL NOT BE IMPACTED DIRECTLY BY
THUNDERSTORMS. HIGHEST POTENTIAL REMAINS WEST OF THE BLUE RIDGE
OVER VIRGINIA. VFR OVERNIGHT.

FRONTAL BOUNDARY IS FORECAST TO STALL OUT TO THE SOUTH OF THE AREA
THROUGH THE WEEKEND THEN RETURN NORTH AS A WARM FRONT EARLY NEXT
WEEK. HUBS LOOK TO STAY DRY ON FRIDAY...BUT A CHANCE OF SHOWERS WILL
RETURN NORTH OVER THE WEEKEND AND THUNDERSTORMS WILL BE POSSIBLE
NEXT WEEK.
-- End Changed Discussion --

&&

.MARINE...
-- Changed Discussion --
ONLY A STEADY 10KT BREEZE THROUGHOUT THE DAY...HELPED BY THE
INCREASE IN CLOUD COVER. BATCHES OF ISOLATED TO SCATTERED SHOWERS
AND TSTMS EXPECTED TO DEVELOP LATER THIS AFTN. TSTMS WILL SUBSIDE
AND DRIFT TOWARD THE ESE LATER TONIGHT AND AWAY FROM THE REGION.

FRONTAL BOUNDARY WILL STALL OUT SOUTH OF THE WATERS THROUGH THE
WEEKEND BEFORE LIFTING BACK TO THE NORTH EARLY NEXT WEEK. GRADIENT
IS EXPECTED TO REMAIN FAIRLY WEAK THROUGH THE PERIOD. AS WINDS
BECOME EAST-SOUTHEAST OVER THE WEEKEND...WINDS MAY FLIRT WITH
MARGINAL SCA CRITERIA OVER A PORTION OF THE BAY.
-- End Changed Discussion --

&&

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

&&

$$
SYNOPSIS...BPP/GMS
NEAR TERM...KRW
SHORT TERM...BPP
LONG TERM...BPP
AVIATION...BPP/KRW
MARINE...BPP/KRW