Alert archive / Maryland / Tornado Warnings in 2009
Tornado Warning 10, NWS Baltimore/Washington
NWS Baltimore/Washington issued this tornado warning at Jul 31, 2009, 2:17 PM EDT for Carroll County, Frederick County, Maryland. It was in force for 28 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
- Jul 31, 2009, 2:17 PM EDT (18:17 UTC)
- Expired
- Jul 31, 2009, 2:45 PM EDT
- In force
- 28 min
- Issued by
- NWS Baltimore/Washington
- Area
- Storm-based polygon
Counties Carroll County, MD, Frederick County, MD
The radar
The Sterling radar (KLWX), 65 km from the middle of the area, began a volume at 18:17 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 watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Jul 31, 1:18 PM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
The nearest sounding before it
Washington/Dulle, VA (KIAD), launched 12:00Z, 6.3 hours before the alert went out and 65 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.
- Mixed-layer CAPE
- 276 J/kg
- Mixed-layer CIN
- -61 J/kg
- Mixed-layer LCL
- 888 m above ground
- 0-6 km bulk shear
- 42 kt
- 0-1 km storm-relative helicity
- -25 m²/s²
- 0-3 km storm-relative helicity
- 18 m²/s²
- Significant tornado parameter
- -0.0
- Supercell composite
- -0.3
What forecasters said that day
The local office's own words before this tornado 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 tornado warning went out at Jul 31, 2:16 PM EDT, 1 minute earlier.
Area forecast discussion, Jul 31, 2:16 PM EDT, 1 minute before
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</html>Hazardous weather outlook, Jul 31, 1:48 PM EDT, 29 minutes before
HAZARDOUS WEATHER OUTLOOK...UPDATED NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 148 PM EDT FRI JUL 31 2009 ANZ530>543-DCZ001-MDZ006-007-011-013-014-016>018-VAZ052>057- 011000- 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- 148 PM EDT FRI JUL 31 2009 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 NUMEROUS SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS THE AREA THIS AFTERNOON AND EVENING. SOME OF THE STORMS MAY BE SEVERE...PRODUCING DAMAGING WIND GUSTS...HEAVY RAIN AND POSSIBLE ISOLATED TORNADOES. A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR THE OUTLOOK AREA UNTIL 9 PM. A GALE WARNING IS IN EFFECT FOR THE MARYLAND CHESAPEAKE BAY FROM SANDY POINT TO SMITH POINT...AND THE TIDAL POTOMAC RIVER FROM COBB ISLAND TO SMITH POINT...UNTIL MIDNIGHT TONIGHT. A SMALL CRAFT ADVISORY IS IN EFFECT FOR THE TIDAL POTOMAC RIVER ABOVE COBB ISLAND...AND MARYLAND CHESAPEAKE BAY...NORTH OF SANDY POINT...FROM THIS AFTERNOON THROUGH LATE TONIGHT. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED LATER THIS AFTERNOON AND EVENING. MDZ003>005-009-010-501-502-VAZ021-025>031-036>042-050-051- WVZ050>055-501>504-011000- WASHINGTON-FREDERICK MD-CARROLL-MONTGOMERY-HOWARD- EXTREME WESTERN ALLEGANY-CENTRAL AND EASTERN ALLEGANY-HIGHLAND- AUGUSTA-ROCKINGHAM-SHENANDOAH-FREDERICK VA-PAGE-WARREN-CLARKE- NELSON-ALBEMARLE-GREENE-MADISON-RAPPAHANNOCK-FAUQUIER-LOUDOUN- ORANGE-CULPEPER-HAMPSHIRE-MORGAN-BERKELEY-JEFFERSON-PENDLETON- HARDY-WESTERN GRANT-EASTERN GRANT-WESTERN MINERAL-EASTERN MINERAL- 148 PM EDT FRI JUL 31 2009 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 NUMEROUS SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS THE AREA THIS AFTERNOON AND EVENING. SOME OF THE STORMS MAY BE SEVERE...PARTICULARLY ALONG AND EAST OF THE BLUE RIDGE...PRODUCING DAMAGING WIND GUSTS...HEAVY RAIN...AND POSSIBLE ISOLATED TORNADOES. A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 9 PM FOR MOST COUNTIES EAST OF THE BLUE RIDGE. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED LATER THIS AFTERNOON AND EVENING. KRAMAR
In the hours before
Local storm report, Jul 31, 8:32 AM EDT, 5 hours 45 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
832 AM EDT FRI JUL 31 2009
..TIME.. ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE.. ....MAG.... ..COUNTY LOCATION.. ST.. ...SOURCE....
..REMARKS..
0451 PM HAIL 1 WNW LUCKETTS 39.22N 77.55W
07/26/2009 E1.00 INCH LOUDOUN VA PUBLIC
STORM SPOTTER RELAYED REPORT BY NEIGHBOR
&&
EVENT NUMBER LWX0900385
KRAMARSpecial weather statement, Jul 31, 1:00 PM EDT, 1 hour 17 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 100 PM EDT FRI JUL 31 2009 MDZ003-004-VAZ028-031-042-WVZ052-053-311800- WASHINGTON MD-FREDERICK MD-CLARKE VA-LOUDOUN VA-JEFFERSON WV- BERKELEY WV-FREDERICK VA- 100 PM EDT FRI JUL 31 2009 ...SHOWERS AND THUNDERSTORMS TO AFFECT WASHINGTON...FREDERICK MARYLAND... CLARKE...LOUDOUN ...JEFFERSON...BERKELEY AND FREDERICK VIRGINIA COUNTIES... AT 1257 PM EDT...DOPPLER RADAR INDICATED SHOWERS WITH GUSTY WINDS ALONG A LINE EXTENDING FROM 2 MILES SOUTHEAST OF TOMAHAWK TO 2 MILES SOUTH OF HAYFIELD...MOVING EAST AT 40 MPH. LOCATIONS THAT WILL LIKELY BE AFFECTED BY THESE STORMS INCLUDE CEDAR HILL...ALBIN...MARTINSBURG...INWOOD...STEPHENSON...CLEAR BROOK... BUNKER HILL...VANVILLE...BRUCETOWN AND WADESVILLE. WIND GUSTS OF 40 TO 50 MPH AND OCCASIONAL THUNDER CAN BE EXPECTED WITH THESE STORMS. BAJ
Special weather statement, Jul 31, 1:10 PM EDT, 1 hour 7 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 110 PM EDT FRI JUL 31 2009 MDZ009-VAZ042-052-053-311800- MONTGOMERY MD-LOUDOUN VA-PRINCE WILLIAM/MANASSAS/MANASSAS PARK VA- FAIRFAX VA- 110 PM EDT FRI JUL 31 2009 ...STRONG STORM TO AFFECT MONTGOMERY...LOUDOUN...PRINCE WILLIAM/MANASSAS/MANASSAS PARK AND FAIRFAX COUNTIES... AT 110 PM EDT...DOPPLER RADAR INDICATED A STRONG STORM 3 MILES SOUTHWEST OF BULL RUN...MOVING NORTHEAST AT 40 MPH. LOCATIONS THAT WILL LIKELY BE AFFECTED BY THIS STORM INCLUDE SUDLEY...MANASSAS PARK...CENTREVILLE...CHANTILLY...OAKTON...WOLF TRAP...VIENNA...RESTON...BELLEVIEW AND TYSONS CORNER. WIND GUSTS OF 40 TO 50 MPH CAN BE EXPECTED WITH THIS STORM. KRAMAR
Special weather statement, Jul 31, 1:35 PM EDT, 42 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 135 PM EDT FRI JUL 31 2009 VAZ026-027-029-030-039>041-051-311830- MADISON VA-CULPEPER VA-PAGE VA-RAPPAHANNOCK VA-FAUQUIER VA-WARREN VA- SHENANDOAH VA-ROCKINGHAM VA- 135 PM EDT FRI JUL 31 2009 ...STRONG SHOWERS TO AFFECT MADISON...CULPEPER...PAGE... RAPPAHANNOCK...FAUQUIER...WARREN...SHENANDOAH AND ROCKINGHAM COUNTIES... AT 134 PM EDT...DOPPLER RADAR INDICATED A LINE OF STRONG SHOWERS ALONG A LINE EXTENDING FROM 2 MILES EAST OF TOMS BROOK TO 4 MILES NORTHWEST OF SHENANDOAH...MOVING EAST AT 30 MPH. LOCATIONS THAT WILL LIKELY BE AFFECTED BY THESE STORMS INCLUDE STANLEY...LURAY...FRONT ROYAL...BIG MEADOWS...SPERRYVILLE...HUME AND DELAPLANE. WIND GUSTS OF 40 TO 50 MPH CAN BE EXPECTED WITH THIS STORM. BAJ
The office that day
Everything else NWS Baltimore/Washington issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 31, 3:58 AM EDT | Gale Warning | LWX | 12 hr | |
| Jul 31, 1:55 PM EDT | Severe Thunderstorm Warning | LWX | Culpeper, Madison, Page, Rappahannock | 50 min |
| Jul 31, 1:58 PM EDT | Severe Thunderstorm Warning | LWX | Loudoun | 47 min |
| Jul 31, 2:08 PM EDT | Special Marine Warning | LWX | 97 min | |
| Jul 31, 2:24 PM EDT | Special Marine Warning | LWX | 108 min | |
| Jul 31, 3:03 PM EDT | Special Marine Warning | LWX | 76 min | |
| Jul 31, 3:13 PM EDT | Special Marine Warning | LWX | 2 hr | |
| Jul 31, 3:27 PM EDT | Special Marine Warning | LWX | 85 min | |
| Jul 31, 3:44 PM EDT | Special Marine Warning | LWX | 21 min | |
| Jul 31, 3:53 PM EDT | Special Marine Warning | LWX | 63 min | |
| Jul 31, 5:38 PM EDT | Special Marine Warning | LWX | 70 min | |
| Jul 31, 6:00 PM EDT | Special Marine Warning | LWX | 90 min | |
| Jul 31, 2:06 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Baltimore, Howard, Montgomery, Prince George's, City of Baltimore | 39 min |
| Jul 31, 2:10 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Carroll | 15 min |
| Jul 31, 2:40 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Baltimore, Carroll, Harford, Howard, Montgomery and 1 more | 50 min |
| Jul 31, 3:28 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Baltimore, Harford, Prince George's | 15 min |
Nearby
Tornado Warnings in Maryland, 2009Every tornado warning in 2009Tornadoes in 2009
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.