Alert archive / Maryland / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 38, NWS Baltimore/Washington

April 6, 20174 counties in Maryland

NWS Baltimore/Washington issued this severe thunderstorm warning at Apr 6, 2017, 4:18 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: Apr 6, 2017, 4:18 PM EDT (20:18 UTC)
Expired: Apr 6, 2017, 4:45 PM EDT
In force: 27 min
Issued by: NWS Baltimore/Washington
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

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 20:19 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Apr 6, 12:45 PM EDT	Severe Thunderstorm Watch	SPC	4 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 8.3 hours before the alert went out and 76 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: 550 m above ground
0-6 km bulk shear: 75 kt
0-1 km storm-relative helicity: 243 m²/s²
0-3 km storm-relative helicity: 459 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 Apr 6, 3:23 PM EDT, 55 minutes earlier.

Area forecast discussion, Apr 6, 3:23 PM EDT, 55 minutes before

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Hazardous weather outlook, Apr 6, 2:25 PM EDT, 1 hour 53 minutes before

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In the hours before

Local storm report, Apr 6, 3:56 PM EDT, 22 minutes before

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Local storm report, Apr 6, 3:57 PM EDT, 21 minutes before

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Local storm report, Apr 6, 4:04 PM EDT, 14 minutes before

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Local storm report, Apr 6, 4:07 PM EDT, 11 minutes before

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Local storm report, Apr 6, 4:12 PM EDT, 6 minutes before

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Local storm report, Apr 6, 4:18 PM EDT, 0 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
Apr 6, 10:32 AM EDT	Winter Weather Advisory	LWX	Highland	27 hr
Apr 6, 11:41 AM EDT	Special Marine Warning	LWX		64 min
Apr 6, 11:41 AM EDT	Severe Thunderstorm Warning	LWX	King George, Stafford	38 min
Apr 6, 12:03 PM EDT	Special Marine Warning	LWX		87 min
Apr 6, 12:17 PM EDT	Severe Thunderstorm Warning	LWX	Orange, Spotsylvania	29 min
Apr 6, 12:43 PM EDT	Severe Thunderstorm Warning	LWX	Culpeper, Fairfax, Fauquier, Orange, Prince William, Spotsylvania and 4 more	47 min
Apr 6, 12:50 PM EDT	Wind Advisory	LWX	Albemarle, Amherst, Augusta, Clarke, Frederick, Greene and 13 more	30 hr
Apr 6, 1:00 PM EDT	Special Marine Warning	LWX		45 min
Apr 6, 1:12 PM EDT	Severe Thunderstorm Warning	LWX	Arlington, Fairfax, Fauquier, Loudoun, Prince William, Stafford and 5 more	48 min
Apr 6, 1:26 PM EDT	Tornado Warning	LWX	Fairfax, Loudoun, Prince William	19 min
Apr 6, 1:53 PM EDT	Special Marine Warning	LWX		82 min
Apr 6, 2:30 PM EDT	Special Marine Warning	LWX		90 min
Apr 6, 4:21 PM EDT	Special Marine Warning	LWX		54 min
Apr 6, 4:24 PM EDT	Freeze Watch	LWX	Albemarle, Amherst, Augusta, Clarke, Culpeper, Fauquier and 17 more	21 hr
Apr 6, 7:57 PM EDT	Small Craft Advisory	LWX		48 hr
Apr 6, 3:18 AM EDT	Coastal Flood Advisory	LWX	Calvert, Harford, Saint Mary's	25 hr
Apr 6, 1:57 PM EDT	Severe Thunderstorm Warning	LWX	Baltimore, Carroll, Howard, Montgomery	48 min
Apr 6, 2:01 PM EDT	Severe Thunderstorm Warning	LWX	Anne Arundel, Baltimore, Calvert, Howard, Montgomery, Prince George's and 1 more	44 min
Apr 6, 2:48 PM EDT	Severe Thunderstorm Warning	LWX	Baltimore, Harford	27 min
Apr 6, 6:15 PM EDT	Areal Flood Warning	LWX	Baltimore	6 hr

Nearby

Severe Thunderstorm Warnings in Maryland, 2017 Every severe thunderstorm warning in 2017

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.