Alert archive / Maryland / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 307, NWS Baltimore/Washington

November 6, 20185 counties in Maryland

NWS Baltimore/Washington issued this severe thunderstorm warning at Nov 6, 2018, 11:52 AM EST for 5 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: Nov 6, 2018, 11:52 AM EST (16:52 UTC)
Expired: Nov 6, 2018, 12:30 PM EST
In force: 38 min
Issued by: NWS Baltimore/Washington
Area: Storm-based polygon
Tornado: Possible
Hail: 0.75 in
Wind: 60.0 mph

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

The radar

The Sterling radar (KLWX), 80 km from the middle of the area, began a volume at 16:54 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

Washington/Dulle, VA (KIAD), launched 12:00Z, 4.9 hours before the alert went out and 72 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 502 m above ground
0-6 km bulk shear: 75 kt
0-1 km storm-relative helicity: 375 m²/s²
0-3 km storm-relative helicity: 468 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 Nov 5, 3:01 PM EST, 20 hours 51 minutes earlier.

Area forecast discussion, Nov 5, 3:01 PM EST, 20 hours 51 minutes before

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Hazardous weather outlook, Nov 5, 4:28 PM EST, 19 hours 24 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
Nov 6, 9:51 AM EST	Special Marine Warning	LWX		33 min
Nov 6, 11:23 AM EST	Special Marine Warning	LWX		97 min
Nov 6, 11:24 AM EST	Special Marine Warning	LWX		96 min
Nov 6, 12:54 PM EST	Coastal Flood Advisory	LWX	Arlington, City of Alexandria, City of Falls Church	9 hr
Nov 6, 1:13 PM EST	Special Marine Warning	LWX		92 min
Nov 6, 7:47 AM EST	Areal Flood Warning	LWX	Prince George's	4 hr
Nov 6, 10:03 AM EST	Wind Advisory	LWX	Grant, Pendleton	7 hr

Nearby

Severe Thunderstorm Warnings in Maryland, 2018 Every severe thunderstorm warning in 2018

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.