Alert archive / Virginia / Severe Thunderstorm Warnings in 2016

Severe Thunderstorm Warning 225, NWS Baltimore/Washington

July 25, 20167 counties in Virginia; Charles County, Montgomery County, Prince George's County, Maryland

NWS Baltimore/Washington issued this severe thunderstorm warning at Jul 25, 2016, 5:44 PM EDT for 7 counties in Virginia; Charles County, Montgomery County, Prince George's County, Maryland. It was in force for 18 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 25, 2016, 5:44 PM EDT (21:44 UTC)
Expired: Jul 25, 2016, 6:02 PM EDT
In force: 18 min
Issued by: NWS Baltimore/Washington
Area: Storm-based polygon
Hail: 1.0 in
Wind: 70.0 mph

Counties Charles County, MD, Montgomery County, MD, Prince George's County, MD, Arlington County, VA, City of Alexandria, VA, City of Fairfax, VA, City of Falls Church, VA, City of Manassas Park, VA, Fairfax County, VA, Prince William County, VA

The radar

The Sterling radar (KLWX), 31 km from the middle of the area, began a volume at 21:44 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 25, 3:30 PM EDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 9.7 hours before the alert went out and 23 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 494 J/kg
Mixed-layer CIN: -150 J/kg
Mixed-layer LCL: 1400 m above ground
0-6 km bulk shear: 14 kt
0-1 km storm-relative helicity: 47 m²/s²
0-3 km storm-relative helicity: 56 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 Jul 25, 4:32 PM EDT, 1 hour 12 minutes earlier.

Area forecast discussion, Jul 25, 4:32 PM EDT, 1 hour 12 minutes before

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Hazardous weather outlook, Jul 25, 3:45 PM EDT, 1 hour 59 minutes before

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In the hours before

Local storm report, Jul 25, 12:17 PM EDT, 5 hours 27 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1217 PM EDT MON JUL 25 2016

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

0704 PM     TSTM WND DMG     KEEZLETOWN              38.42N  78.80W
07/24/2016                   ROCKINGHAM         VA   BROADCAST MEDIA

            LARGE TREE AND BRANCHES DOWN

&&

EVENT NUMBER LWX1604561

MSE

Local storm report, Jul 25, 4:13 PM EDT, 1 hour 31 minutes before

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Local storm report, Jul 25, 4:50 PM EDT, 54 minutes before

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Local storm report, Jul 25, 5:38 PM EDT, 6 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 24, 8:50 PM EDT	Severe Thunderstorm Warning	LWX	Clarke, Fauquier, Frederick, Warren	17 min
Jul 24, 8:53 PM EDT	Severe Thunderstorm Warning	LWX	Loudoun	25 min
Jul 25, 12:58 AM EDT	Special Marine Warning	LWX		92 min
Jul 25, 1:30 AM EDT	Special Marine Warning	LWX		2 hr
Jul 25, 3:14 PM EDT	Severe Thunderstorm Warning	LWX	Clarke, Frederick, City of Winchester	46 min
Jul 25, 3:33 PM EDT	Severe Thunderstorm Warning	LWX	Page, Shenandoah, Warren	42 min
Jul 25, 3:38 PM EDT	Heat Advisory	LWX	King George, Nelson, Orange, Spotsylvania, Stafford, City of Charlottesville and 1 more	26 hr
Jul 25, 4:24 PM EDT	Small Craft Advisory	LWX		5 hr
Jul 25, 4:42 PM EDT	Severe Thunderstorm Warning	LWX	Clarke, Fauquier, Frederick, Loudoun, Prince William	48 min
Jul 25, 5:16 PM EDT	Severe Thunderstorm Warning	LWX	Fairfax, Fauquier, Loudoun, Prince William	44 min
Jul 25, 5:42 PM EDT	Special Marine Warning	LWX		2 hr
Jul 25, 7:47 PM EDT	Special Marine Warning	LWX		88 min
Jul 25, 1:05 AM EDT	Severe Thunderstorm Warning	LWX	Anne Arundel, Calvert	26 min
Jul 25, 1:36 AM EDT	Severe Thunderstorm Warning	LWX	Calvert	13 min
Jul 25, 3:31 PM EDT	Severe Thunderstorm Warning	LWX	Carroll, Frederick	44 min
Jul 25, 3:47 PM EDT	Severe Thunderstorm Warning	LWX	Frederick, Washington	43 min
Jul 25, 4:04 PM EDT	Severe Thunderstorm Warning	LWX	Carroll, Frederick, Washington	39 min
Jul 25, 4:28 PM EDT	Severe Thunderstorm Warning	LWX	Carroll, Frederick	47 min

Nearby

Severe Thunderstorm Warnings in Virginia, 2016 Severe Thunderstorm Warnings in Maryland, 2016 Every severe thunderstorm warning in 2016

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.