Alert archive / Maryland / Severe Thunderstorm Warnings in 2020
Severe Thunderstorm Warning 41, NWS Baltimore/Washington
NWS Baltimore/Washington issued this severe thunderstorm warning at Apr 9, 2020, 12:13 PM EDT for Anne Arundel County, Prince George's County, Maryland. It was in force for 47 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
- Apr 9, 2020, 12:13 PM EDT (16:13 UTC)
- Expired
- Apr 9, 2020, 1:00 PM EDT
- In force
- 47 min
- Issued by
- NWS Baltimore/Washington
- Area
- Storm-based polygon
- Hail
- 0.75 in
- Wind
- 60.0 mph
Counties Anne Arundel County, MD, Prince George's County, MD
The radar
The Sterling radar (KLWX), 68 km from the middle of the area, began a volume at 16:14 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 |
|---|---|---|---|
| Apr 9, 12:01 PM EDT | Severe Thunderstorm Watch | SPC | 4 hr |
The nearest sounding before it
Washington/Dulle, VA (KIAD), launched 12:00Z, 4.2 hours before the alert went out and 60 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
- 20 J/kg
- Mixed-layer CIN
- -589 J/kg
- Mixed-layer LCL
- 1002 m above ground
- 0-6 km bulk shear
- 47 kt
- 0-1 km storm-relative helicity
- 394 m²/s²
- 0-3 km storm-relative helicity
- 416 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
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 Apr 9, 12:09 PM EDT, 4 minutes earlier.
Area forecast discussion, Apr 9, 12:09 PM EDT, 4 minutes before
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</html>Hazardous weather outlook, Apr 9, 12:06 PM EDT, 7 minutes before
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</html>In the hours before
Local storm report, Apr 9, 8:06 AM EDT, 4 hours 7 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
806 AM EDT THU APR 09 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0725 AM MARINE TSTM WIND 2 SE COBB ISLAND 38.24N 76.83W
04/09/2020 M39 MPH ANZ537 MD BUOY
&&
EVENT NUMBER LWX2000943
DHLocal storm report, Apr 9, 8:09 AM EDT, 4 hours 4 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
809 AM EDT THU APR 09 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0800 AM MARINE TSTM WIND 7 SSE SAINT GEORGE ISLA 38.01N 76.45W
04/09/2020 M39 MPH ANZ537 MD BUOY
&&
EVENT NUMBER LWX2000944
DHLocal storm report, Apr 9, 8:21 AM EDT, 3 hours 52 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
821 AM EDT THU APR 09 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0818 AM MARINE TSTM WIND POINT LOOKOUT 38.04N 76.32W
04/09/2020 M40 MPH ANZ537 MD BUOY
&&
EVENT NUMBER LWX2000945
DHLocal storm report, Apr 9, 8:49 AM EDT, 3 hours 24 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
849 AM EDT THU APR 09 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0847 AM MARINE TSTM WIND 8 E SMITH ISLAND 37.97N 75.88W
04/09/2020 M40 MPH ANZ543 MD BUOY
&&
EVENT NUMBER LWX2000946
DHSpecial weather statement, Apr 9, 10:57 AM EDT, 1 hour 16 minutes before
Special Weather Statement National Weather Service Baltimore MD/Washington DC 1057 AM EDT Thu Apr 9 2020 MDZ003-501-502-VAZ027-028-503-504-WVZ050>053-055-501>506-091615- Washington-Extreme Western Allegany-Central and Eastern Allegany- Shenandoah-Frederick VA-Western Highland-Eastern Highland- Hampshire-Morgan-Berkeley-Jefferson-Hardy-Western Grant- Eastern Grant-Western Mineral-Eastern Mineral-Western Pendleton- Eastern Pendleton- Including the cities of Hagerstown, Frostburg, Cumberland, Strasburg, Woodstock, Mount Jackson, New Market, Winchester, Hightown, Monterey, Romney, Paw Paw, Martinsburg, Charles Town, Shepherdstown, Moorefield, Bayard, Mount Storm, Petersburg, Elk Garden, Antioch, Keyser, New Creek, Ridgeville, Russelldale, Headsville, Fort Ashby, Riverton, Brandywine, Franklin, Oak Flat, Ruddle, and Sugar Grove 1057 AM EDT Thu Apr 9 2020 ...SUDDEN ONSET OF GUSTY WINDS... As of 10:57 AM...a strong cold front accompanied by showers was located from just east of Cumberland Maryland to Franklin West Virginia. This front is moving east at about 50 MPH. A sudden onset of westerly wind gusts in excess of 50 MPH are expected. This includes eastern West Virginia, western Maryland and Highland County in western Virginia. Winds of this magnitude are capable of damaging tents, blowing around unsecured outdoor objects, and knocking down branches, trees and power lines resulting in power outages. The onset of strong winds should reach a line from Hagerstown Maryland to Martinsburg West Virginia to Moorefield West Virginia to Monterey Virginia by about 11:30 AM, and then the Catoctins of northern Maryland to Winchester Virginia to Shenandoah Mountain by noon. Should showers or thunderstorms along this front intensify and wind gusts in excess of 58 MPH become imminent, Severe Thunderstorm Warnings would be issued. DHOF
Special weather statement, Apr 9, 11:19 AM EDT, 54 minutes before
Special Weather Statement National Weather Service Baltimore MD/Washington DC 1119 AM EDT Thu Apr 9 2020 DCZ001-MDZ004-005-503>505-VAZ025-026-029>031-038>040-051>054-501- 502-505>508-092130- District of Columbia-Frederick MD-Carroll-Northwest Montgomery- Central and Southeast Montgomery-Northwest Howard-Augusta- Rockingham-Page-Warren-Clarke-Greene-Madison-Rappahannock- Culpeper-Prince William/Manassas/Manassas Park-Fairfax- Arlington/Falls Church/Alexandria-Northern Fauquier- Southern Fauquier-Western Loudoun-Eastern Loudoun- Northern Virginia Blue Ridge-Central Virginia Blue Ridge- Including the cities of Washington, Frederick, Ballenger Creek, Eldersburg, Westminster, Germantown, Damascus, Bethesda, Rockville, Gaithersburg, Silver Spring, Lisbon, Staunton, Waynesboro, Stuarts Draft, Harrisonburg, Luray, Shenandoah, Stanley, Front Royal, Berryville, Stanardsville, Madison, Culpeper, Dale City, Manassas, Woodbridge, Lake Ridge, Montclair, Reston, Herndon, Annandale, Centreville, Chantilly, McLean, Franconia, Arlington, Alexandria, Falls Church, Warrenton, Turnbull, Purcellville, Leesburg, Ashburn, Sterling, Big Meadows, and Wintergreen 1119 AM EDT Thu Apr 9 2020 ...SUDDEN ONSET OF GUSTY WINDS... As of 11:15 AM...a strong cold front accompanied by showers and developing thunderstorms was located from just west of Hagerstown Maryland to just west of Martinsburg West Virginia to near Shenandoah Mountain. This front is moving east at about 50 MPH. A sudden onset of westerly wind gusts in excess of 50 MPH is expected. This includes north-central Maryland, northern Virginia, the northern and central Virginia Blue Ridge and the central Shenandoah Valley. Winds of this magnitude are capable of damaging tents, blowing around unsecured outdoor objects, and knocking down branches, trees and power lines resulting in power outages. The onset of strong winds should reach a line from Frederick Maryland to Harrisonburg Virginia by noon, and then approach the Interstate 95 corridor between noon and 1:00 PM. Should showers or thunderstorms along this front intensify and wind gusts in excess of 58 MPH become imminent, Severe Thunderstorm Warnings would be issued. DHOF
The office that day
Everything else NWS Baltimore/Washington issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 8, 8:13 PM EDT | Wind Advisory | LWX | Albemarle, Amherst, Arlington, Augusta, Clarke, Fairfax and 21 more | 23 hr |
| Apr 9, 2:42 AM EDT | Severe Thunderstorm Warning | LWX | Highland | 63 min |
| Apr 9, 3:14 AM EDT | Severe Thunderstorm Warning | LWX | Augusta, City of Staunton, City of Waynesboro | 61 min |
| Apr 9, 5:33 AM EDT | Special Marine Warning | LWX | 51 min | |
| Apr 9, 7:58 AM EDT | Special Marine Warning | LWX | 66 min | |
| Apr 9, 11:44 AM EDT | Severe Thunderstorm Warning | LWX | Clarke, Frederick, Loudoun, City of Winchester | 46 min |
| Apr 9, 12:00 PM EDT | Special Marine Warning | LWX | 90 min | |
| Apr 9, 12:06 PM EDT | Special Marine Warning | LWX | 114 min | |
| Apr 9, 12:43 PM EDT | Special Marine Warning | LWX | 52 min | |
| Apr 9, 12:58 PM EDT | Special Marine Warning | LWX | 37 min | |
| Apr 9, 7:37 PM EDT | Gale Warning | LWX | 26 hr | |
| Apr 9, 7:37 PM EDT | Small Craft Advisory | LWX | 46 hr | |
| Apr 9, 7:38 PM EDT | Wind Advisory | LWX | Albemarle, Amherst, Arlington, Augusta, Clarke, Fairfax and 20 more | 22 hr |
| Apr 9, 7:47 PM EDT | Freeze Watch | LWX | Albemarle, Amherst, Augusta, Clarke, Culpeper, Fauquier and 16 more | 19 hr |
| Apr 9, 3:19 AM EDT | Coastal Flood Advisory | LWX | Anne Arundel | 9 hr |
| Apr 9, 11:51 AM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Carroll, Frederick, Howard, Montgomery | 39 min |
| Apr 9, 12:24 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Harford, City of Baltimore | 66 min |
| Apr 9, 1:16 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Carroll, Harford, City of Baltimore | 18 min |
| Apr 9, 2:52 AM EDT | Severe Thunderstorm Warning | LWX | Grant, Hardy | 38 min |
Nearby
Severe Thunderstorm Warnings in Maryland, 2020Every severe thunderstorm warning in 2020
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.