Alert archive / Virginia / Severe Thunderstorm Warnings in 2014

Severe Thunderstorm Warning 9, NWS Baltimore/Washington

May 10, 20145 counties in Virginia

NWS Baltimore/Washington issued this severe thunderstorm warning at May 10, 2014, 1:26 PM EDT for 5 counties in Virginia. It was in force for 49 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
May 10, 2014, 1:26 PM EDT (17:26 UTC)
Expired
May 10, 2014, 2:15 PM EDT
In force
49 min
Issued by
NWS Baltimore/Washington
Area
Storm-based polygon

Counties City of Winchester, VA, Clarke County, VA, Frederick County, VA, Shenandoah County, VA, Warren County, VA

The radar

The Sterling radar (KLWX), 66 km from the middle of the area, began a volume at 17:27 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 5.4 hours before the alert went out and 74 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Washington/Dulle, VA at 12:00Z on 2014-05-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 111 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Washington/Dulle, VA at 12:00Z on 2014-05-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 38 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
111 J/kg
Mixed-layer CIN
-68 J/kg
Mixed-layer LCL
1281 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
38 m²/s²
0-3 km storm-relative helicity
24 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, 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 this severe thunderstorm warning went out at May 10, 10:30 AM EDT, 2 hours 56 minutes earlier.

Area forecast discussion, May 10, 10:30 AM EDT, 2 hours 56 minutes before
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1030 AM EDT SAT MAY 10 2014

.SYNOPSIS...
HIGH PRESSURE OFF THE SOUTHEAST COAST WILL LEAD TO WARM AND HUMID
CONDITIONS THIS WEEKEND THROUGH THE FIRST PART OF THE NEW WEEK. A
COLD FRONT WILL ENTER THE REGION DURING MIDWEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
THE MIDDLE ATLANTIC REGION WILL REMAIN SANDWICHED IN BETWEEN A
RIDGE TO THE SOUTH AND AN UPPER TROUGH OVER THE GREAT LAKES
STATES. THE FLOW AROUND THESE SYSTEMS IS HELPING TO PULL ABUNDANT
MID AND HIGH LEVEL MOISTURE ACROSS THE MIDDLE ATLANTIC. WE EXPECT
CLOUD COVER TO CONTINUE TO STREAM IN FROM THE SOUTHWEST TODAY. AT
THE LOWER LEVELS...SOUTHERLY FLOW IS AIDING IN MOIST CONDITIONS
WITH DEWPOINTS IN THE 60S COMMON JUST ABOUT EVERYWHERE THIS
MORNING. BREAKS IN THE CLOUD DECK HAVE OCCURRED EAST OF THE BLUE
RIDGE WHICH HAS AIDED IN DESTABILIZING THE BOUNDARY LAYER A BIT
MORE THAN EXPECTED. THIS SHOULD LEAD TO BETTER MIXING AT LEAST
EARLY ON WITH TEMPERATURES APPROACHING THE LOWER 80S EAST OF THE
MOUNTAINS. SOUNDING PROFILE THIS AM AT KIAD INDICATED STEEPENING
LAPSE RATES WITH POTENTIAL FOR GUSTY WINDS WITH ANY
SHOWERS/THUNDERSTORMS THAT DEVELOP A BIT LATER TODAY. CAP WILL
HOLD OVER THE NEXT FEW HOURS OVER THE METRO AREAS BEFORE HEATING
CAUSES EROSION OF THE CIN. CAPE MAY BE AMPLE ENOUGH AND WITH
ENERGY APPROACHING FROM THE WEST...WILL SEE SHOWERS AND ISOLATED
THUNDERSTORMS DEVELOPING...SOME OF WHICH MAY PRODUCE DAMAGING
WINDS.

THREAT FOR SHOWERS AND THUNDERSTORMS WILL LIKELY DIMINISH LATER
THIS EVENING BUT CLOUDS WILL REMAIN IN PLACE OVERNIGHT. LOW TEMPS
WILL FALL BACK TO THE 60S IN THE METRO AREAS AND 50S ELSEWHERE.

&&

.SHORT TERM /SUNDAY/...
SUNDAY...RIDGING MAKES FOR A NICE MOTHERS DAY. LIGHT NWLY FLOW
BECOMES WLY. THE DOWNSLOPING FLOW AND SUNNY SKIES...AND 10 TO 12C
850MB TEMPS MAKE FOR MAX TEMPS IN THE LOW 80S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
THE LONG TERM CAN SORT OF BE DIVIDED INTO 2 PARTS - THE SUMMERY
PART F0LLOWED BY THE WETTER PART W/ TEMPS MORE TYPICAL OF ERLY
MAY.

A SUBTROPICAL RDG REMINISCENT OF WHAT THIS AREA OFTEN SEES IN JUL
WL BE THE DOMINANT WX FACTOR FM SUN NGT INTO SOME POINT IN MIDWK.
THIS WL CAUSE LOW TEMPS TO RISE FM THE U50S SUN NGT TO THE LM60S
MON AND TUE NGT. HIGHS MON AND TUE WL LKLY REACH THE U80S...PSBLY
EVEN 90 IN SPOTS. CNVCTN WL LKLY BE RESTRICTED TO MTNS ON MON.
TSTMS AGN PSBL TUE AFTN/EVE.

INCRSD CLD CVRG ON WED AHD OF SFC FNT/UPR LVL TROF ENTERING THE MS
VLLY. THIS SHOULD HINDER INSOLATION AND ALLOW TEMPS TO BE HELD TO
THE L80S. CHCS OF PCPN SHOULD EXIST DURG THE DAY..BUT THE BEST
CHCS SHOULD BE WED AFTN/EVE AS THE FNT DRAWS CLOSER.

CLRG MAY BE SLOW TO COME...AS THE FNT APPEARS TO BE CAUGHT IN SSW-
NNE UPR LVL FLOW. THIS IN TURN WL KEEP PCPN CHCS OVR THE AREA FOR
MUCH OF THE 2ND HALF OF THE WK. XTNSV CLD CVR WL ACT TO HOLD
TEMPS DOWN - HIGHS IN THE 70S/LOWS FALLING BACK INTO THE 50S THU
NGT. THIS WL ALSO WORK TO TEMPER SVR THREAT.

&&

.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
SHOWERS AND ISOLATED THUNDERSTORMS WILL DEVELOP THIS AFTERNOON AND
CONTINUE INTO THIS EVENING. SOME OF THE STORMS COULD PRODUCE GUSTY
WINDS AND HEAVY DOWNPOURS. WILL CONTINUE MENTION WITHIN THE
TERMINAL FORECASTS. THREAT WILL DIMINISH BY LATE EVENING. VFR
CONDITIONS EXPECTED SUNDAY INTO MONDAY.

CNVCTV CHCS WL EXIST FM TUE AFTN THRU MUCH OF THE REST OF THE
WK...ALTHO SVR CONDS NOT XPCTD. THE 2ND HALF OF THE WK IS ALSO
XPCTD TO BE QUITE CLDY.

&&

.MARINE...
SWLY FLOW INCREASES THROUGH THE DAY WITH SCA FOR ALL WATERS BY NOON.
20 TO 25 KT GUSTS. GUSTY SHOWERS AND THUNDERSTORMS WILL BE
POSSIBLE LATER THIS AFTERNOON INTO THIS EVENING WHICH MAY WARRANT
SPECIAL MARINE WARNINGS.

WINDS MAY PICK UP ON THU AS A CD FNT MOVES THRU THE WATERS. AN SCA
MAY BE NEEDED. AFTR A VERY WARM 1ST HALF OF THE WK...W/ PSBL TSTM
CHCS TUE...CLDS WL INCRS W/ COOLER TEMPS AND CHCS OF RA/ISOLD
TSTMS FOR THE 2ND HALF OF THE WK.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 AM EDT SUNDAY FOR ANZ530>533-535-
     536-538>542.
     SMALL CRAFT ADVISORY UNTIL 2 AM EDT SUNDAY FOR ANZ534-537-543.

&&

SYNOPSIS...KRW
NEAR TERM...KRW
SHORT TERM...KS
LONG TERM...ABW
AVIATION...KRW
MARINE...KRW
Hazardous weather outlook, May 10, 10:39 AM EDT, 2 hours 47 minutes before
HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1039 AM EDT SAT MAY 10 2014

ANZ530>543-DCZ001-MDZ006-007-011-013-014-016>018-VAZ052>057-
111245-
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-
1039 AM EDT SAT MAY 10 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...TODAY AND TONIGHT

A SMALL CRAFT ADVISORY IS IN EFFECT FOR LOWER SOUTHERN MARYLAND
WATERS THIS MORNING...THEN EXPANDS TO ALL WATERS FOR THIS AFTERNOON
INTO TONIGHT.

GUSTY SHOWERS AND THUNDERSTORMS ARE LIKELY ACROSS THE WATERS THIS
EVENING. SPECIAL MARINE WARNINGS MAY BE NECESSARY.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

A SMALL CRAFT ADVISORY MAY BE REQUIRED THURSDAY.

.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>506-111245-
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-
1039 AM EDT SAT MAY 10 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...TODAY AND TONIGHT

SHOWERS AND ISOLATED THUNDERSTORMS WILL DEVELOP ACROSS THE REGION
THIS AFTERNOON INTO THIS EVENING. SOME OF THE STORMS COULD PRODUCE
DAMAGING WINDS. THE THREAT WILL DIMINISH BY LATE EVENING.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

The office that day

Everything else NWS Baltimore/Washington issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 10, 1:12 PM EDTSevere Thunderstorm WarningLWXClarke, Frederick, City of Winchester33 min
May 10, 1:18 PM EDTSpecial Marine WarningLWX117 min
May 10, 3:18 PM EDTSpecial Marine WarningLWX57 min
May 10, 4:16 PM EDTSpecial Marine WarningLWX89 min
May 10, 1:25 PM EDTSevere Thunderstorm WarningLWXCarroll, Frederick, Montgomery50 min
May 10, 1:28 PM EDTSevere Thunderstorm WarningLWXBaltimore, Harford47 min

Nearby

Severe Thunderstorm Warnings in Virginia, 2014Every severe thunderstorm warning in 2014

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.