Alert archive / Maryland / Severe Thunderstorm Warnings in 2014

Severe Thunderstorm Warning 255, NWS Baltimore/Washington

October 7, 2014Calvert County, Saint Mary's County, Maryland

NWS Baltimore/Washington issued this severe thunderstorm warning at Oct 7, 2014, 11:18 PM EDT for Calvert County, Saint Mary's County, 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: Oct 7, 2014, 11:18 PM EDT (03:18 UTC)
Expired: Oct 7, 2014, 11:45 PM EDT
In force: 27 min
Issued by: NWS Baltimore/Washington
Area: Storm-based polygon

Counties Calvert County, MD, Saint Mary's County, MD

The radar

The Sterling radar (KLWX), 107 km from the middle of the area, began a volume at 03:19 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 nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 00:00Z, 3.3 hours before the alert went out and 111 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: 96 J/kg
Mixed-layer CIN: -137 J/kg
Mixed-layer LCL: 1222 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: 146 m²/s²
0-3 km storm-relative helicity: 190 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.5

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 Oct 7, 9:48 PM EDT, 1 hour 30 minutes earlier.

Area forecast discussion, Oct 7, 9:48 PM EDT, 1 hour 30 minutes before

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Hazardous weather outlook, Oct 7, 11:04 PM EDT, 14 minutes before

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In the hours before

Local storm report, Oct 7, 8:08 PM EDT, 3 hours 10 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
808 PM EDT TUE OCT 07 2014

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

0740 PM     MARINE TSTM WIND 2 SE DAHLGREN           38.31N  77.03W
10/07/2014  M40 MPH          ANZ536             VA   BUOY

&&

EVENT NUMBER LWX1401016

JACKSON

Local storm report, Oct 7, 9:52 PM EDT, 1 hour 26 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
Oct 7, 8:04 PM EDT	Special Marine Warning	LWX		56 min
Oct 7, 8:41 PM EDT	Special Marine Warning	LWX		64 min
Oct 7, 8:51 PM EDT	Severe Thunderstorm Warning	LWX	Albemarle, Nelson, City of Charlottesville	39 min
Oct 7, 9:45 PM EDT	Special Marine Warning	LWX		60 min
Oct 7, 10:37 PM EDT	Special Marine Warning	LWX		83 min
Oct 7, 10:42 PM EDT	Special Marine Warning	LWX		63 min

Nearby

Severe Thunderstorm Warnings in Maryland, 2014 Every severe thunderstorm warning in 2014

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.