Alert archive / Virginia / Severe Thunderstorm Warnings in 2013

Severe Thunderstorm Warning 4, NWS Baltimore/Washington

January 30, 201310 counties in Virginia; 7 counties in Maryland

NWS Baltimore/Washington issued this severe thunderstorm warning at Jan 30, 2013, 7:41 PM EST for 10 counties in Virginia; 7 counties in Maryland. 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: Jan 30, 2013, 7:41 PM EST (00:41 UTC)
Expired: Jan 30, 2013, 8:30 PM EST
In force: 49 min
Issued by: NWS Baltimore/Washington
Area: Storm-based polygon

Counties Anne Arundel County, MD, Baltimore County, MD, Charles County, MD, City of Baltimore, MD, Howard 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, VA, City of Manassas Park, VA, Fairfax County, VA, Fauquier County, VA, Prince William County, VA, Stafford County, VA

The radar

The Sterling radar (KLWX), 32 km from the middle of the area, began a volume at 00:42 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
Jan 30, 6:31 PM EST	Tornado Watch	SPC	8 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 0.7 hours before the alert went out and 24 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: 320 J/kg
Mixed-layer CIN: -9 J/kg
Mixed-layer LCL: 511 m above ground
0-6 km bulk shear: 98 kt
0-1 km storm-relative helicity: 803 m²/s²
0-3 km storm-relative helicity: 880 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 7.1

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 Jan 30, 6:59 PM EST, 42 minutes earlier.

Area forecast discussion, Jan 30, 6:59 PM EST, 42 minutes before

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Hazardous weather outlook, Jan 30, 6:52 PM EST, 49 minutes before

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In the hours before

Local storm report, Jan 30, 7:22 PM EST, 19 minutes before

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Local storm report, Jan 30, 7:32 PM EST, 9 minutes before

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Local storm report, Jan 30, 7:33 PM EST, 8 minutes before

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Special weather statement, Jan 30, 7:34 PM EST, 7 minutes before

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Local storm report, Jan 30, 7:37 PM EST, 4 minutes before

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Local storm report, Jan 30, 7:40 PM EST, 1 minute 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
Jan 30, 7:34 PM EST	Special Weather Statement	LWX	Arlington, Fairfax, City of Alexandria, City of Fairfax, City of Falls Church	26 min
Jan 30, 8:28 PM EST	Special Weather Statement	LWX	Arlington, City of Alexandria	32 min
Jan 30, 9:12 PM EST	Flash Flood Warning	LWX	Albemarle, Augusta, Culpeper, Fauquier, Greene, Madison and 4 more	6 hr
Jan 30, 9:39 PM EST	Areal Flood Warning	LWX	Fauquier, Loudoun	6 hr
Jan 30, 9:42 PM EST	River Flood Warning	LWX	Loudoun	31 hr
Jan 30, 9:56 PM EST	Flash Flood Warning	LWX	Augusta, Highland, Page, Rockingham, City of Harrisonburg, City of Staunton and 1 more	6 hr
Jan 30, 10:30 PM EST	Flash Flood Warning	LWX	Arlington, Fairfax, Fauquier, Loudoun, Prince William, City of Alexandria and 4 more	6 hr
Jan 30, 11:11 PM EST	Areal Flood Warning	LWX	Rockingham, Shenandoah	6 hr
Jan 31, 12:27 AM EST	Special Weather Statement	LWX	King George, Spotsylvania, Stafford, City of Fredericksburg	33 min
Jan 31, 2:20 AM EST	Areal Flood Warning	LWX	Augusta, Highland, Rockingham, City of Harrisonburg, City of Staunton, City of Waynesboro	3 hr
Jan 31, 2:34 AM EST	Areal Flood Warning	LWX	Albemarle, Culpeper, Fauquier, Greene, Madison, Nelson and 5 more	17 hr
Jan 31, 2:46 AM EST	River Flood Watch	LWX	Clarke	7 hr
Jan 31, 2:54 AM EST	Winter Weather Advisory	LWX	Arlington, Fairfax, Fauquier, Highland, Spotsylvania, Stafford and 4 more	36 hr
Jan 31, 5:36 AM EST	Areal Flood Warning	LWX	Loudoun	7 hr
Jan 31, 7:00 AM EST	Areal Flood Warning	LWX	Clarke, Shenandoah, Warren	6 hr
Jan 31, 7:21 AM EST	River Flood Warning	LWX	Culpeper, Orange	11 hr
Jan 31, 7:31 AM EST	River Flood Watch	LWX	Fairfax	7 hr
Jan 31, 7:47 AM EST	River Flood Watch	LWX	Culpeper, Fauquier	10 min
Jan 31, 7:55 AM EST	River Flood Warning	LWX	Culpeper, Fauquier	20 hr
Jan 31, 9:36 AM EST	River Flood Warning	LWX	Loudoun	34 hr
Jan 31, 10:00 AM EST	River Flood Warning	LWX	Clarke	38 hr
Jan 31, 10:04 AM EST	River Flood Watch	LWX	Shenandoah, Warren	5 hr
Jan 31, 3:03 PM EST	Gale Warning	LWX		27 hr
Jan 31, 3:03 PM EST	Small Craft Advisory	LWX		15 hr
Jan 30, 8:21 PM EST	Special Weather Statement	LWX	Harford	24 min
Jan 30, 8:59 PM EST	Special Weather Statement	LWX	Anne Arundel	31 min
Jan 30, 9:31 PM EST	River Flood Warning	LWX	Montgomery	23 hr
Jan 31, 1:21 AM EST	Flash Flood Warning	LWX	Anne Arundel, Calvert, Charles, Prince George's, Saint Mary's	3 hr
Jan 31, 1:52 AM EST	Severe Thunderstorm Warning	LWX	Calvert, Saint Mary's	53 min
Jan 31, 2:39 AM EST	River Flood Warning	LWX	Frederick	28 hr
Jan 31, 7:31 AM EST	Areal Flood Warning	LWX	Montgomery	3 hr
Jan 31, 8:38 AM EST	Areal Flood Warning	LWX	Anne Arundel, Howard, Prince George's	13 hr
Jan 30, 9:50 PM EST	River Flood Watch	LWX	Berkeley, Jefferson	5 hr
Jan 31, 2:32 AM EST	River Flood Warning	LWX	Pendleton	5 hr
Jan 31, 2:32 AM EST	River Flood Warning	LWX	Berkeley, Jefferson	26 hr
Jan 31, 9:31 AM EST	River Flood Warning	LWX	Hampshire	11 hr
Jan 31, 2:46 PM EST	River Flood Warning	LWX	Morgan	16 hr

Nearby

Severe Thunderstorm Warnings in Virginia, 2013 Severe Thunderstorm Warnings in Maryland, 2013 Every severe thunderstorm warning in 2013

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.