Alert archive / Maryland / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 231, NWS Baltimore/Washington

September 9, 20154 counties in Maryland

NWS Baltimore/Washington issued this severe thunderstorm warning at Sep 9, 2015, 9:08 PM EDT for 4 counties in Maryland. It was in force for 38 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: Sep 9, 2015, 9:08 PM EDT (01:08 UTC)
Expired: Sep 9, 2015, 9:46 PM EDT
In force: 38 min
Issued by: NWS Baltimore/Washington
Area: Storm-based polygon

Counties Calvert County, MD, Charles County, MD, Prince George's County, MD, Saint Mary's County, MD

The radar

The Sterling radar (KLWX), 83 km from the middle of the area, began a volume at 01:09 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, 1.1 hours before the alert went out and 133 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: 1113 J/kg
Mixed-layer CIN: -41 J/kg
Mixed-layer LCL: 948 m above ground
0-6 km bulk shear: 8 kt
0-1 km storm-relative helicity: 36 m²/s²
0-3 km storm-relative helicity: 43 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 Sep 9, 3:10 PM EDT, 5 hours 58 minutes earlier.

Area forecast discussion, Sep 9, 3:10 PM EDT, 5 hours 58 minutes before

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Hazardous weather outlook, Sep 9, 6:43 PM EDT, 2 hours 25 minutes before

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In the hours before

Local storm report, Sep 9, 8:25 PM EDT, 43 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
Sep 9, 9:02 PM EDT	Special Marine Warning	LWX		88 min
Sep 9, 10:23 PM EDT	Small Craft Advisory	LWX		36 hr
Sep 10, 2:02 PM EDT	Special Marine Warning	LWX		88 min
Sep 10, 2:08 PM EDT	Special Marine Warning	LWX		2 hr
Sep 10, 2:46 PM EDT	Special Marine Warning	LWX		119 min
Sep 10, 7:15 PM EDT	Flash Flood Warning	LWX	Albemarle, City of Charlottesville	3 hr
Sep 10, 2:15 PM EDT	Flash Flood Warning	LWX	Baltimore	3 hr
Sep 10, 2:37 PM EDT	Flash Flood Warning	LWX	Baltimore, City of Baltimore	3 hr
Sep 10, 3:07 PM EDT	Flash Flood Warning	LWX	Anne Arundel	3 hr

Nearby

Severe Thunderstorm Warnings in Maryland, 2015 Every severe thunderstorm warning in 2015

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.