Alert archive / Virginia / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 76, NWS Baltimore/Washington

May 22, 2018Fairfax County, Loudoun County, Virginia; Frederick County, Montgomery County, Maryland

NWS Baltimore/Washington issued this severe thunderstorm warning at May 22, 2018, 3:25 PM EDT for Fairfax County, Loudoun County, Virginia; Frederick County, Montgomery County, Maryland. It was in force for 50 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 22, 2018, 3:25 PM EDT (19:25 UTC)
Expired
May 22, 2018, 4:15 PM EDT
In force
50 min
Issued by
NWS Baltimore/Washington
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Frederick County, MD, Montgomery County, MD, Fairfax County, VA, Loudoun County, VA

The radar

The Sterling radar (KLWX), 20 km from the middle of the area, began a volume at 19:25 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.

IssuedProductOfficeLasted
May 22, 2:33 PM EDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 7.4 hours before the alert went out and 20 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 2018-05-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 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 2018-05-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 60 square meters per square second.193958Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
744 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
60 m²/s²
0-3 km storm-relative helicity
99 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 22, 10:22 AM EDT, 5 hours 3 minutes earlier.

Area forecast discussion, May 22, 10:22 AM EDT, 5 hours 3 minutes before
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Hazardous weather outlook, May 22, 2:51 PM EDT, 34 minutes before
Hazardous Weather Outlook
National Weather Service Baltimore MD/Washington DC
251 PM EDT Tue May 22 2018

ANZ530>543-DCZ001-MDZ011-013-014-016>018-508-VAZ052>057-231900-
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-Southern Baltimore-Prince Georges-
Anne Arundel-Charles-St. Marys-Calvert-Southeast Harford-
Prince William/Manassas/Manassas Park-Fairfax-
Arlington/Falls Church/Alexandria-Stafford-Spotsylvania-
King George-
251 PM EDT Tue May 22 2018

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 Severe Thunderstorm Watch is in effect through 9pm for portions
of southern and central Maryland, northern Virginia, and the
District of Columbia. Scattered severe thunderstorms with damaging
wind gusts and large hail are possible this afternoon and
evening. Heavy rain from thunderstorms could also result in
isolated instances of flooding.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

MDZ003>006-501>507-VAZ025>031-036>040-050-051-501>508-WVZ050>053-
055-501>506-231900-
Washington-Frederick MD-Carroll-Northern Baltimore-
Extreme Western Allegany-Central and Eastern Allegany-
Northwest Montgomery-Central and Southeast Montgomery-
Northwest Howard-Central and Southeast Howard-Northwest Harford-
Augusta-Rockingham-Shenandoah-Frederick VA-Page-Warren-Clarke-
Nelson-Albemarle-Greene-Madison-Rappahannock-Orange-Culpeper-
Northern Fauquier-Southern Fauquier-Western Highland-
Eastern Highland-Western Loudoun-Eastern Loudoun-
Northern Virginia Blue Ridge-Central Virginia Blue Ridge-
Hampshire-Morgan-Berkeley-Jefferson-Hardy-Western Grant-
Eastern Grant-Western Mineral-Eastern Mineral-Western Pendleton-
Eastern Pendleton-
251 PM EDT Tue May 22 2018

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 Severe Thunderstorm Watch is in effect through 9pm for portions
of northern and central Virginia, and portions of central
Maryland. Scattered severe thunderstorms with damaging wind gusts
and large hail are possible this afternoon and evening. Heavy rain
from thunderstorms could also result in isolated instances of
flooding.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

In the hours before

Local storm report, May 22, 2:44 PM EDT, 41 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
244 PM EDT TUE MAY 22 2018

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1240 AM     FLASH FLOOD      2 ENE YANKEETOWN        38.70N  78.92W
05/22/2018                   ROCKINGHAM         VA   BROADCAST MEDIA

            SIGNIFICANT FLASH FLOODING REPORTED IN THE YANKEETOWN
            AND FULKS RUN AREAS, WITH WATER IN VEHICLES, NUMEROUS
            ROADS CLOSED AND MANY STREAMS OUT OF THEIR BANKS.

&&

EVENT NUMBER LWX1800368

JE
Local storm report, May 22, 2:48 PM EDT, 37 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
248 PM EDT TUE MAY 22 2018

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1240 AM     FLASH FLOOD      4 SSE YANKEETOWN        38.63N  78.92W
05/22/2018                   ROCKINGHAM         VA   BROADCAST MEDIA

            A PORTION OF HOPKINS GAP ROAD WAS SCOURED OUT NEAR
            TURNER RUN AND THE BARE RIDGE ROAD INTERSECTION.

&&

EVENT NUMBER LWX1800369

JE

The office that day

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

IssuedProductOfficeCountiesLasted
May 21, 10:29 PM EDTFlash Flood WarningLWXRockingham3 hr
May 21, 11:44 PM EDTSevere Thunderstorm WarningLWXRockingham, City of Harrisonburg29 min
May 22, 12:53 AM EDTRiver Flood WarningLWXRockingham, Shenandoah6 hr
May 22, 6:01 AM EDTAreal Flood WarningLWXShenandoah11 hr
May 22, 3:14 PM EDTSevere Thunderstorm WarningLWXAlbemarle, Greene, Madison, Orange, Rockingham, City of Charlottesville46 min
May 22, 3:29 PM EDTSpecial Marine WarningLWX2 hr
May 22, 4:27 PM EDTSpecial Marine WarningLWX2 hr
May 22, 4:30 PM EDTSpecial Marine WarningLWX2 hr
May 22, 4:43 PM EDTAreal Flood WarningLWXArlington, Fairfax, Prince William, City of Alexandria, City of Fairfax, City of Falls Church4 hr
May 22, 4:48 PM EDTSevere Thunderstorm WarningLWXFairfax, Prince William, City of Fairfax42 min
May 22, 5:17 PM EDTAreal Flood WarningLWXFairfax4 hr
May 22, 5:39 PM EDTSpecial Marine WarningLWX2 hr
May 22, 5:47 PM EDTAreal Flood WarningLWXShenandoah6 hr
May 22, 6:29 PM EDTSpecial Marine WarningLWX2 hr
May 22, 5:08 PM EDTSevere Thunderstorm WarningLWXCharles, Prince George's52 min
May 22, 5:24 PM EDTSevere Thunderstorm WarningLWXAnne Arundel16 min
May 21, 8:16 PM EDTAreal Flood WarningLWXGrant3 hr

Nearby

Severe Thunderstorm Warnings in Virginia, 2018Severe Thunderstorm Warnings in Maryland, 2018Every severe thunderstorm warning in 2018

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.