Severe Thunderstorm Warning 77, NWS Baltimore/Washington

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
329 PM EDT WED JUN 18 2014

.SYNOPSIS...
HIGH PRESSURE WILL REMAIN ACROSS THE SOUTHEASTERN STATES THROUGH
TONIGHT. A WEAK COLD FRONT WILL MOVE INTO THE REGION FROM THE
NORTHWEST ON THURSDAY AND WILL STALL JUST SOUTH OF THE AREA FRIDAY
INTO THE WEEKEND. ANOTHER WEAK COLD FRONT APPROACHES THE REGION NEXT
WEEK.

&&

.NEAR TERM /THROUGH THURSDAY/...
AS OF 18Z...BOUNDARY OVER THE DC AREA IS FROM OVERNIGHT/MORNING
ACTIVITY OVER PA. DEWPOINTS ARE AROUND 70F ALONG THIS BOUNDARY
WITH UPR 60S BOTH NORTH (BALTIMORE) AND SOUTH (CHARLOTTESVILLE).
WITH TEMPERATURES GENERALLY LOW TO MID 90S...THE HIGHEST HEAT
INDICES ARE AROUND 100 DEGREES IN DC...WITH MID TO UPR 90S
ELSEWHERE. ISOLATED SHOWER/THUNDERSTORM ACTIVITY WILL CONTINUE
ALONG THIS FRONT AS INDICATED FROM THE LATEST FORECAST UPDATE.
LACK OF SHEAR WILL MAKE FOR PULSE ACTIVITY. WILL NEED TO CONTINUE
WATCHING THE MCS OVER IL/MI WHICH HAS A WEAKER RADAR MOSAIC
APPEARANCE...BUT IS STILL PRODUCING COPIOUS LIGHTNING. THERE IS A
SEGMENT OVER SRN WV THAT WILL CONTINUE TRACKING EAST TO OUR SWRN
ZONES AND OTHER ACTIVITY COULD FORM OVER THE TERRAIN.

15Z HRRR IS SIMILAR TO OTHER RECENT RUNS WITH ORGANIZED ACTIVITY
FROM THE MIDWEST DELAYED FOR THE LWX CWA UNTIL LATE TONIGHT/THURSDAY
MORNING. TEMPS A FEW LESS DEGREES THURSDAY WITH 18C 850MB TEMPS
COMPARED TO 20C TODAY. FURTHERMORE...SHOULD PRECIP BE GOING ON
DURING THE DAY...OR CLOUD COVER THICK ENOUGH...MAX TEMPERATURES
COULD BE SEVERAL DEGREES LESS (PERHAPS UPR 80S).
&&

.SHORT TERM /THURSDAY NIGHT/...
COLD FRONT/BOUNDARY STALLS SOUTH OF THE AREA THURSDAY NIGHT THROUGH
FRIDAY WITH A QUIET PERIOD IN AN OTHERWISE ACTIVE SPELL. BRIEF COOL
DOWN THAT CONTINUES INTO THE WEEKEND (AS LONG AS THE BOUNDARY STAYS
SOUTH). WILL NEED TO LOOK OUT FOR SHORTWAVES RIDING THE
BOUNDARY...SUCH AS THE 12Z ECMWF SOLUTION WITH A FRIDAY
NIGHT/SATURDAY MORNING WAVE CROSSING THE AREA.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
COMBINED MOIST WARM AIRMASS ALONG WITH A QUASI-STATIONARY
BOUNDARY AND WEAK PVA CONTINUES TO SUPPORT A CHANCE OF SHOWERS AND
AFTERNOON THUNDERSTORMS THROUGH THE PERIOD. SURFACE LOW PRESSURE
CENTER TRACKING EAST ALONG THE BOUNDARY WILL SUPPORT THE ENHANCED
DEVELOPMENT OF SHOWERS AND THUNDERSTORMS WEDNESDAY.

&&

.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
VFR INTO THIS EVENING OUTSIDE OF ISOLATED TSRA MAINLY ALONG A
EAST-WEST BOUNDARY ACROSS THE DCA AREA AND FROM THE TERRAIN WEST OF
DC METROS. CU FIELD BASED AROUND 5 KFT. ORGANIZED THUNDERSTORM
COMPLEX COULD APPROACH THE TERMINALS LATE TONIGHT OR THURSDAY
MORNING. FRONTAL BOUNDARY SOUTH OF THE TERMINALS THURSDAY NIGHT AND
FRIDAY BEFORE DRIFTING NORTH THIS WEEKEND.

&&

.MARINE...
WLY/NWLY FLOW AROUND 10 KT WITH ISOLATED SHOWERS AND THUNDERSTORMS
FROM DC TO CENTRAL MD. ORGANIZED THUNDERSTORM SYSTEM POSSIBLE
REACHES THE BAY LATE TONIGHT OR THURSDAY MORNING. FRONTAL BOUNDARY
SOUTH OF THE WATERS THURSDAY NIGHT INTO THE WEEKEND. NO SCA IN THE
OUTLOOK PERIOD.

&&

.CLIMATE...
A RECORD HIGH TEMPERATURE WAS REPORTED AT REAGAN NATIONAL AIRPORT
YESTERDAY. THE HIGH WAS 97 DEGREES AND THIS SURPASSES THE OLD
RECORD OF 95 DEGREES SET IN 1991...1957...AND 1945.

MORE RECORD HIGHS ARE POSSIBLE TODAY AT BWI AND DCA. THE LIST
BELOW IS THE RECORD HIGHS FOR THE THREE MAJOR AIRPORTS.

KBWI: RECORD HIGH: 97 IN 1957.
KDCA: RECORD HIGH: 97 IN 1944.
KIAD: RECORD HIGH: 94 IN 2007.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ530-
     531-538-539.

&&

SYNOPSIS...BAJ
NEAR TERM...BAJ
SHORT TERM...BAJ
LONG TERM...CEM
AVIATION...BAJ
MARINE...BAJ
CLIMATE...BAJ

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
132 PM EDT WED JUN 18 2014

ANZ530>543-DCZ001-MDZ006-007-011-013-014-016>018-VAZ052>057-
191545-
CHESAPEAKE BAY NORTH OF POOLES ISLAND MD-
CHESAPEAKE BAY FROM POOLES ISLAND TO SANDY POINT MD-
CHESAPEAKE BAY FROM SANDY POINT TO NORTH BEACH MD-
CHESAPEAKE BAY FROM NORTH BEACH TO DRUM POINT MD-
CHESAPEAKE BAY FROM DRUM POINT MD TO SMITH POINT VA-
TIDAL POTOMAC FROM KEY BRIDGE TO INDIAN HEAD MD-
TIDAL POTOMAC FROM INDIAN HEAD TO COBB ISLAND MD-
TIDAL POTOMAC FROM COBB ISLAND MD TO SMITH POINT VA-
PATAPSCO RIVER INCLUDING BALTIMORE HARBOR-
CHESTER RIVER TO QUEENSTOWN MD-EASTERN BAY-
CHOPTANK RIVER TO CAMBRIDGE MD AND THE LITTLE CHOPTANK RIVER-
PATUXENT RIVER TO BROOMES ISLAND MD-
TANGIER SOUND AND THE INLAND WATERS SURROUNDING BLOODSWORTH
ISLAND-DISTRICT OF COLUMBIA-NORTHERN BALTIMORE-HARFORD-
SOUTHERN BALTIMORE-PRINCE GEORGES-ANNE ARUNDEL-CHARLES-ST. MARYS-
CALVERT-PRINCE WILLIAM/MANASSAS/MANASSAS PARK-FAIRFAX-
ARLINGTON/FALLS CHURCH/ALEXANDRIA-STAFFORD-SPOTSYLVANIA-
KING GEORGE-
132 PM EDT WED JUN 18 2014

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE MARYLAND PORTION OF THE
CHESAPEAKE BAY...TIDAL POTOMAC RIVER...AND ADJACENT COUNTIES IN
CENTRAL MARYLAND AND NORTHERN VIRGINIA AS WELL AS THE DISTRICT OF
COLUMBIA.

.DAY ONE...THIS AFTERNOON AND TONIGHT

HEAT INDICES AROUND 100 DEGREES WILL PERSIST THROUGH THE
BALTIMORE-WASHINGTON METRO AREA THROUGH THIS AFTERNOON.

SCATTERED THUNDERSTORMS ARE EXPECTED THIS AFTERNOON AND EVENING.
A FEW STORMS MAY BE SEVERE WITH DAMAGING WIND GUSTS AND LARGE HAIL.

A DEVELOPED THUNDERSTORM COMPLEX IS EXPECTED TO APPROACH THE AREA
FROM THE NORTHWEST LATE TONIGHT AND MAY CAUSE DAMAGING
WINDS...PARTICULARLY OVER NORTHERN PORTIONS OF THE AREA.

A SMALL CRAFT ADVISORY IS IN EFFECT UNTIL 6PM FOR THE NORTHERN
PORTION OF THE MARYLAND CHESAPEAKE BAY.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED THIS EVENING INTO TONIGHT.

MDZ003>005-009-010-501-502-VAZ025>031-036>040-042-050-051-501>504-
WVZ050>053-055-501>506-191545-
WASHINGTON-FREDERICK MD-CARROLL-MONTGOMERY-HOWARD-
EXTREME WESTERN ALLEGANY-CENTRAL AND EASTERN ALLEGANY-AUGUSTA-
ROCKINGHAM-SHENANDOAH-FREDERICK VA-PAGE-WARREN-CLARKE-NELSON-
ALBEMARLE-GREENE-MADISON-RAPPAHANNOCK-LOUDOUN-ORANGE-CULPEPER-
NORTHERN FAUQUIER-SOUTHERN FAUQUIER-WESTERN HIGHLAND-
EASTERN HIGHLAND-HAMPSHIRE-MORGAN-BERKELEY-JEFFERSON-HARDY-
WESTERN GRANT-EASTERN GRANT-WESTERN MINERAL-EASTERN MINERAL-
WESTERN PENDLETON-EASTERN PENDLETON-
132 PM EDT WED JUN 18 2014

THIS HAZARDOUS WEATHER OUTLOOK IS FOR EASTERN WEST VIRGINIA...
NORTHERN AND CENTRAL VIRGINIA...AND CENTRAL AND WESTERN MARYLAND
WITH THE EXCEPTION OF GARRETT COUNTY.

.DAY ONE...THIS AFTERNOON AND TONIGHT

HEAT INDICES AROUND 100 DEGREES WILL PERSIST OVER NORTHERN
VIRGINIA PIEDMONT THROUGH THIS AFTERNOON.

SCATTERED THUNDERSTORMS ARE EXPECTED THIS AFTERNOON AND EVENING.
A FEW STORMS MAY BE SEVERE WITH DAMAGING WIND GUSTS AND LARGE HAIL.

A DEVELOPED THUNDERSTORM COMPLEX IS EXPECTED APPROACH THE AREA
FROM THE NORTHWEST LATE TONIGHT AND MAY CAUSE DAMAGING
WINDS...PARTICULARLY OVER NORTHERN PORTIONS OF THE AREA.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED LATE THIS AFTERNOON INTO
TONIGHT.

JACKSON