Alert archive / Maryland / Tornado Warnings in 2010

Tornado Warning 16, NWS Baltimore/Washington

August 12, 20104 counties in Maryland

NWS Baltimore/Washington issued this tornado warning at Aug 12, 2010, 4:48 PM EDT for 4 counties in Maryland. It was in force for 27 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: Aug 12, 2010, 4:48 PM EDT (20:48 UTC)
Expired: Aug 12, 2010, 5:15 PM EDT
In force: 27 min
Issued by: NWS Baltimore/Washington
Area: Storm-based polygon

Counties Carroll County, MD, Frederick County, MD, Howard County, MD, Montgomery County, MD

The radar

The Sterling radar (KLWX), 52 km from the middle of the area, began a volume at 20:49 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
Aug 12, 2:51 PM EDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 8.8 hours before the alert went out and 50 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: 3000 J/kg
Mixed-layer CIN: -9 J/kg
Mixed-layer LCL: 657 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 51 m²/s²
0-3 km storm-relative helicity: 85 m²/s²
Significant tornado parameter: 0.9
Supercell composite: 4.4

Open this sounding in Storm Lab

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 Aug 12, 2:49 PM EDT, 1 hour 59 minutes earlier.

Area forecast discussion, Aug 12, 2:49 PM EDT, 1 hour 59 minutes before

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Hazardous weather outlook, Aug 12, 3:00 PM EDT, 1 hour 48 minutes before

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In the hours before

Local storm report, Aug 12, 3:43 PM EDT, 1 hour 5 minutes before

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Local storm report, Aug 12, 3:54 PM EDT, 54 minutes before

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Local storm report, Aug 12, 3:55 PM EDT, 53 minutes before

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Local storm report, Aug 12, 4:00 PM EDT, 48 minutes before

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Special weather statement, Aug 12, 4:16 PM EDT, 32 minutes before

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Local storm report, Aug 12, 4:46 PM EDT, 2 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
Aug 12, 3:34 AM EDT	Small Craft Advisory	LWX		47 hr
Aug 12, 7:07 AM EDT	Severe Thunderstorm Warning	LWX	Arlington, Fairfax, City of Alexandria, City of Fairfax, City of Falls Church	38 min
Aug 12, 7:09 AM EDT	Special Marine Warning	LWX		66 min
Aug 12, 7:23 AM EDT	Flash Flood Warning	LWX	Arlington, City of Falls Church	52 min
Aug 12, 7:37 AM EDT	Special Marine Warning	LWX		95 min
Aug 12, 7:40 AM EDT	Severe Thunderstorm Warning	LWX	Arlington, Fairfax, City of Alexandria, City of Fairfax, City of Falls Church	50 min
Aug 12, 8:00 AM EDT	Special Marine Warning	LWX		2 hr
Aug 12, 9:06 AM EDT	Special Marine Warning	LWX		114 min
Aug 12, 2:12 PM EDT	Special Weather Statement	LWX	Loudoun	33 min
Aug 12, 2:32 PM EDT	Special Weather Statement	LWX	Fauquier	28 min
Aug 12, 2:45 PM EDT	Severe Thunderstorm Warning	LWX	Fairfax, Fauquier, Loudoun, Prince William	45 min
Aug 12, 3:02 PM EDT	Severe Thunderstorm Warning	LWX	Culpeper, Fauquier	43 min
Aug 12, 3:14 PM EDT	Special Marine Warning	LWX		2 hr
Aug 12, 3:31 PM EDT	Severe Thunderstorm Warning	LWX	Fairfax, Prince William, Stafford, City of Manassas, City of Manassas Park	44 min
Aug 12, 3:38 PM EDT	Severe Thunderstorm Warning	LWX	Culpeper, Fauquier, Orange, Spotsylvania, Stafford	52 min
Aug 12, 3:47 PM EDT	Severe Thunderstorm Warning	LWX	King George, Spotsylvania, Stafford, City of Fredericksburg	58 min
Aug 12, 4:03 PM EDT	Tornado Warning	LWX	King George, Spotsylvania, Stafford, City of Fredericksburg	29 min
Aug 12, 4:15 PM EDT	Severe Thunderstorm Warning	LWX	King George	60 min
Aug 12, 4:27 PM EDT	Severe Thunderstorm Warning	LWX	Spotsylvania	31 min
Aug 12, 5:13 PM EDT	Severe Thunderstorm Warning	LWX	Fairfax, Loudoun	62 min
Aug 12, 5:15 PM EDT	Special Marine Warning	LWX		2 hr
Aug 12, 5:39 PM EDT	Special Weather Statement	LWX	Clarke, Loudoun	36 min
Aug 12, 5:49 PM EDT	Flash Flood Warning	LWX	Arlington, Fairfax, City of Alexandria, City of Falls Church	115 min
Aug 12, 6:06 PM EDT	Special Weather Statement	LWX	Arlington, Fairfax, City of Alexandria, City of Fairfax, City of Falls Church	54 min
Aug 12, 6:55 PM EDT	Special Weather Statement	LWX	King George, Prince William, Stafford, City of Fredericksburg, City of Manassas	50 min
Aug 12, 7:10 PM EDT	Coastal Flood Advisory	LWX	Arlington, Fairfax, King George, Stafford, City of Alexandria, City of Fairfax and 1 more	3 days
Aug 12, 5:58 AM EDT	Special Weather Statement	LWX	Frederick	47 min
Aug 12, 6:10 AM EDT	Severe Thunderstorm Warning	LWX	Carroll, Frederick, Howard, Montgomery	35 min
Aug 12, 6:28 AM EDT	Severe Thunderstorm Warning	LWX	Frederick, Howard, Montgomery	32 min
Aug 12, 7:03 AM EDT	Special Weather Statement	LWX	Anne Arundel, Prince George's	27 min
Aug 12, 8:12 AM EDT	Severe Thunderstorm Warning	LWX	Anne Arundel, Calvert, Charles, Prince George's, Saint Mary's	63 min
Aug 12, 9:15 AM EDT	Special Weather Statement	LWX	Calvert, Saint Mary's	30 min
Aug 12, 9:19 AM EDT	Flash Flood Warning	LWX	Calvert, Charles, Prince George's, Saint Mary's	86 min
Aug 12, 9:45 AM EDT	Special Weather Statement	LWX	Calvert, Saint Mary's	45 min
Aug 12, 4:16 PM EDT	Special Weather Statement	LWX	Carroll, Frederick, Washington	44 min
Aug 12, 4:18 PM EDT	Tornado Warning	LWX	Carroll, Frederick	42 min
Aug 12, 4:35 PM EDT	Severe Thunderstorm Warning	LWX	Baltimore, Carroll, Frederick, Washington	55 min
Aug 12, 5:17 PM EDT	Tornado Warning	LWX	Carroll, Frederick, Howard, Montgomery	43 min

Nearby

Tornado Warnings in Maryland, 2010 Every tornado warning in 2010 Tornadoes in 2010

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.