A southerly flow around high pressure over the western Atlantic produced hot and humid conditions during the late morning and afternoon hours of the 9th. Heat indices up to 105 degrees were reported across portions of northern and central Virginia during this time.
Every event with a place to put it; 4 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS LWX wrote it up.
A southerly flow around high pressure over the western Atlantic produced hot and humid conditions during the late morning and afternoon hours of the 9th. Heat indices up to 105 degrees were reported across portions of northern and central Virginia during this time.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Baltimore/Washington wrote its last area forecast discussion before the first event at Jun 9, 11:17 AM EST, 35 minutes earlier.
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1217 PM EDT THU JUN 9 2011
.SYNOPSIS...
BERMUDA HIGH OVER THE ATLANTIC WILL CONTINUE TO BRING HOT AND HUMID
CONDITIONS TODAY. A SERIES OF UPPER-LEVEL DISTURBANCES WILL PASS
THROUGH THE REGION TONIGHT THROUGH FRIDAY TRIGGERING SHOWERS AND
THUNDERSTORMS. A BACKDOOR COLD FRONT WILL STALL OUT OVER THE REGION
FRIDAY NIGHT THROUGH SATURDAY BEFORE A STRONGER COLD FRONT FROM THE
WEST MOVES THROUGH SUNDAY. HIGH PRESSURE WILL RETURN FOR EARLY NEXT
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE...EXPANDED THE HEAT ADVISORY TO INCLUDE PORTIONS OF THE
NORTHERN SHENANDOAH VALLEY...AS ALLUDED TO IN PREV DISC. ALSO
BUMPED UP FORECAST TEMPS A COUPLE OF DEGREES AREAWIDE. HEAT INDEX
VALUES ACROSS THE METRO AREAS WILL APPROACH THE UPPER END OF THE
105-110 RANGE LATER THIS AFTN.
PREV DISC...
AT 10AM...WE ARE ALREADY SEEING TEMPS SHOOT UP THROUGH THE 80S
AND BY 11AM WE WILL LIKELY SEE MOST IF NOT ALL SITES ABOVE 90.
THIS CLIMB WILL END LATER THIS AFTN BUT NOT BEFORE ANOTHER LIKELY
RECORD SETTING DAY. DEWPOINTS THAT ARE A COUPLE OF DEGREES HIGHER
THAN THIS TIME YESTERDAY MAKING CONDITIONS THAT MUCH MORE
UNCOMFORTABLE. RELIEF IS SLOWLY APPROACHING AND WON/T ARRIVE UNTIL
AFTER WE HAVE GONE THROUGH MUCH OF THE DAYTIME HR W/ THESE
CONDITIONS.
A HEAT ADVISORY STILL IN EFFECT FOR AREAS EAST OF THE BLUE
RIDGE...THOUGH THE SHENANDOAH VALLEY ALSO WILL RECEIVE CONDITIONS
ALMOST AS HOT AS THE PIEDMONT. THOSE RESIDING ALONG THE I-81
CORRIDOR SHOULD TAKE SIMILAR PRECAUTIONS W/ TEMPS RISING INTO THE
M-U90S AND HEAT INDICES REACHING JUST INTO THE 100S AT TIMES.
URBAN CENTERS DC/BALT WILL ESPECIALLY BE SUSCEPTIBLE TO THE
HOTTEST CONDITIONS IN THE REGION. DEWPOINTS THAT FLIRTED W/ M70S
EARLIER THIS MORNING WILL MIX OUT A COUPLE OF DEGREES...BUT LEVEL
OUT AROUND 70 THIS AFTN WHICH IS PLENTY MOIST TO CREATE HEAT
INDICES WELL INTO THE 100S...JUST SHY OF 110 AT TIMES.
THE PRIME AREA OF PRECIP AND CONVECTION RESIDES ALONG THE UPPER
MIDWEST FROM THE CHICAGOLAND AREA...EXPANDING INTO PARTS OF NEW
ENGLAND. THOUGH THIS AREA WILL CONTINUE TO SEE THE MOST WIDESPREAD
DEVELOPMENT...THE RELATIVE PROXIMITY - THE MOIST LOW LEVEL
CONDITIONS AND THE VERY /THOUGH CONDITIONALLY/ UNSTABLE
ENVIRONMENT WILL ALLOW FOR OUR REGION TO SEE SOME ACTIVITY LATER
TODAY. AS W/ THE TSTMS THAT DEVELOPED ACROSS THE SWRN QUADRANT OF
THE CWA LATE LAST NIGHT...TERRAIN INDUCED CONVECTION WILL BE THE
MORE LIKELY MODE THIS AFTN/EVE. IF ANY OUTFLOW BOUNDARIES FROM
THIS ACTIVITY SPREAD OUT TOWARD THE PIEDMONT...THEN SHOWERS/TSTMS
WILL BECOME MORE LIKELY TOWARD THE METRO AREAS LATER TONIGHT.
BY THIS TIME...THE UPPER SHORTWAVE AND SFC COLD FRONT WILL ALSO BE
ON THE DOORSTEP OF THE CWA /ACROSS THE POTOMAC HIGHLANDS/ WHICH
WILL THEN ADD THE NECESSARY FORCING FOR MORE WIDESPREAD ACTIVITY
OUTSIDE OF THE HIGHER TERRAIN. HAIL APPEARS TO BE THE PRIMARY
THREAT IN ISOLATED STORMS...BUT MORE ORGANIZED ACTIVITY ALSO WILL
HAVE A DAMAGING WIND THREAT.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
UPPER-LEVEL HIGH PRESSURE WILL BE CENTERED ACROSS THE TENNESSEE
VALLEYS INTO THE CAROLINAS FRIDAY THROUGH FRIDAY NIGHT WHILE A
SERIES OF UPPER-LEVEL DISTURBANCES PASS THROUGH IN A WESTERLY FLOW
ALOFT. HOT AND HUMID CONDITIONS WILL PERSIST THROUGH FRIDAY...BUT IT
MAY NOT BE QUITE AS HOT AS RECENT DAYS DUE TO DEEPER MOISTURE IN THE
ATMOSPHERE. MAX TEMPS FRIDAY WILL RANGE FROM THE 80S IN THE
MOUNTAINS TO THE LOWER AND MIDDLE 90S ACROSS MOST OTHER LOCATIONS.
HOT AND HUMID CONDITIONS WILL CAUSE MODERATE AMOUNTS OF INSTABILITY
TO DEVELOP. THE INSTABILITY WILL COMBINE WITH A SURFACE PRESSURE
TROUGH AND THE UPPER-LEVEL DISTURBANCE TO TRIGGER SCATTERED SHOWERS
AND THUNDERSTORMS. THE BEST CHANCE FOR THUNDERSTORMS WILL BE DURING
THE AFTERNOON AND EVENING HOURS FRIDAY.
A BACKDOOR COLD FRONT WILL APPROACH THE EASTERN CWA FRIDAY NIGHT AS
HIGH PRESSURE BUILDS OVER NEW ENGLAND BEHIND. FRIDAY NIGHT WILL
STILL TURN OUT QUITE WARM AND HUMID ACROSS THE AREA WITH MIN TEMPS
RANGING FROM THE 60S ACROSS MOST LOCATIONS ALONG AND WEST OF THE
BLUE RIDGE MOUNTAINS TO THE LOWER AND MIDDLE 70S IN WASHINGTON AND
BALTIMORE. SCATTERED SHOWERS AND THUNDERSTORMS MAY PERSIST OVERNIGHT
FRIDAY AS THE BOUNDARY APPROACHES THE REGION.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
THE BACKDOOR COLD FRONT WILL STALL OUT OVER THE NORTHEASTERN CWA
SATURDAY. WARM AND HUMID CONDITIONS WILL PERSIST CAUSING THE
POSSIBILITY FOR MORE SHOWERS AND THUNDERSTORMS...ESPECIALLY DURING
THE AFTERNOON AND EVENING. A STRONGER COLD FRONT WILL PASS THROUGH
THE WEST SUNDAY...BRINGING THE CHANCE FOR MORE SHOWERS AND
THUNDERSTORMS.
HIGH PRESSURE WILL BUILD OVER THE REGION EARLY NEXT WEEK BEHIND THE
FRONT...BRINGING DRY AND COOLER CONDITIONS ALONG WITH NOTICEABLY
LESS HUMIDITY. HIGH PRESSURE WILL MOVE OFF THE COAST DURING THE
MIDDLE PORTION OF NEXT WEEK.
&&
.AVIATION /16Z THURSDAY THROUGH MONDAY/...
VFR CONDITIONS EXPECTED INTO EARLY AFTN. CUMULUS /HGT 5KFT/ POP IN
EARNEST BY EARLY AFTERNOON...AND RETAINED MENTION OF BOTH CB AND
VCSH FOR NOW DURING THE AFTN. MVFR CONDITIONS ARE LIKELY AGAIN
LATE TONIGHT IN THE USUAL LOCATIONS...AND THIS WILL BE REFLECTED
IN THE 12Z TAFS.
A SERIES OF UPPER-LEVEL DISTURBANCES ALONG WITH A STALLED BOUNDARY
OVER THE TERMINALS WILL BRING A CHANCE FOR SHOWERS AND THUNDERSTORMS
FRIDAY THROUGH SATURDAY. THE BEST CHANCE WILL BE DURING THE
AFTERNOON AND EVENING HOURS EACH DAY WHEN INSTABILITY IS AT ITS
HIGHEST. A STRONGER COLD FRONT WILL PASS THROUGH THE TERMINALS
SUNDAY...BRINGING A CHANCE FOR MORE SHOWERS AND T-STORMS.
HIGH PRESSURE WILL BUILD OVER THE TERMINALS EARLY NEXT WEEK.
&&
.MARINE...
THERE IS A CHANCE OF THUNDERSTORMS IN THE MARINE AREA THIS EVENING.
LIGHT WINDS ARE EXPECTED OUTSIDE OF CONVECTIVE DEVELOPMENT TODAY AND
TONIGHT.
A SERIES OF UPPER-LEVEL DISTURBANCES WILL PASS THROUGH THE WATERS
FRIDAY AND SATURDAY WHILE A BACKDOOR COLD FRONT STALLS OUT OVERHEAD.
THESE FEATURES WILL BRING A CHANCE FOR SHOWERS AND THUNDERSTORMS
BOTH DAYS WITH THE BEST CHANCE DURING THE AFTERNOON AND EVENING
HOURS.
A STRONGER COLD FRONT WILL PASS THROUGH SUNDAY WITH MORE SHOWERS AND
T-STORMS POSSIBLE. HIGH PRESSURE WILL BRING DRIER CONDITIONS EARLY
NEXT WEEK. WIND SPEEDS THROUGHOUT MOST OF THE PERIOD WILL REMAIN
BELOW SCA CRITERIA...BUT GUSTY WINDS ARE POSSIBLE IN ANY T-STORMS.
&&
.CLIMATE...
FAST FACT...YESTERDAYS HIGH OF 99 AT DCA WAS THE FOURTH DAY ABOVE
95 DEGREES ALREADY THIS YEAR. ONLY 1925 HAD MORE DAYS ABOVE 95
THIS EARLY IN THE SEASON. THE SAME STATISTIC IS TRUE AT BWI.
RECORDS WILL BE APPROACHED AGAIN TODAY...AS SHOWN BELOW.
DAILY RECORD MAX AND MIN TEMPS /DEG F/ FOR JUN 9...
SITE MAX /YEAR/ MIN /YEAR/
DCA 102 /1874/ 77 /2008/
BWI 98 /1874...1933/ 78 /1933/
IAD 96 /1999/ 70 /1965...1973...1990/
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR DCZ001.
MD...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR MDZ003>007-
009>011-013-014-016>018.
VA...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR VAZ028-030-031-
036>040-042-050>057-501-502.
WV...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR WVZ051>053.
MARINE...NONE.
&&
UPDATE...GMS
PREV DISCUSSION...JCE/JRKHAZARDOUS WEATHER OUTLOOK...UPDATED NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 1218 PM EDT THU JUN 9 2011 ANZ530>543-DCZ001-MDZ006-007-011-013-014-016>018-VAZ052>057- 101500- 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- 1218 PM EDT THU JUN 9 2011 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 A HEAT ADVISORY IS IN EFFECT FROM NOON TO 8 PM TODAY. SCATTERED THUNDERSTORMS ARE EXPECTED LATE THIS AFTERNOON INTO THE EVENING. AN ISOLATED STRONG THUNDERSTORM WITH GUSTY WINDS OR SMALL HAIL IS POSSIBLE. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. MDZ003>005-009-010-501-502-VAZ025>031-036>040-042-050-051-501>504- WVZ050>053-055-501>506-101500- 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- 1218 PM EDT THU JUN 9 2011 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 A HEAT ADVISORY IS IN EFFECT FROM NOON TO 8 PM ON THURSDAY FOR A PORTION OF THE NORTHERN SHENANDOAH VALLEY AND AREAS EAST OF THE BLUE RIDGE. SCATTERED THUNDERSTORMS ARE EXPECTED DURING THE LATE AFTERNOON AND EVENING. A FEW OF THE STORMS MAY BECOME SEVERE WITH LARGE HAIL AND DAMAGING WINDS THE PRIMARY THREATS. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY SCATTERED THUNDERSTORMS ARE EXPECTED BOTH FRIDAY AND SATURDAY. A FEW STORMS MAY BECOME SEVERE WITH LARGE HAIL AND DAMAGING WINDS. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS POSSIBLE LATE THIS AFTERNOON...AND AGAIN FRIDAY OR SATURDAY.
The national radar mosaic for the moment the first event began.
5 heat. Local standard time, as filed.
Heat indices in excess of 100 degrees were recorded at Reagan National Airport.
Heat indices in excess of 100 degrees were recorded at Manassas.
Heat indices were estimated to be in excess of 100 degrees across Stafford County.
Heat indices were estimated to be in excess of 100 degrees across Spotsylvania County.
Heat indices were estimated to be in excess of 100 degrees across King George County.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Virginia in 2011Every state in 2011This day in weather historyWarnings in Virginia, June 2011
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 327988, 327990, 327991, 327992, 327993.