Alert archive / Maryland / Severe Thunderstorm Warnings in 2014

Severe Thunderstorm Warning 228, NWS Baltimore/Washington

August 31, 2014Anne Arundel County, Montgomery County, Prince George's County, Maryland

NWS Baltimore/Washington issued this severe thunderstorm warning at Aug 31, 2014, 6:18 PM EDT for Anne Arundel County, Montgomery County, Prince George's County, Maryland. It was in force for 57 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 31, 2014, 6:18 PM EDT (22:18 UTC)
Expired
Aug 31, 2014, 7:15 PM EDT
In force
57 min
Issued by
NWS Baltimore/Washington
Area
Storm-based polygon

Counties Anne Arundel County, MD, Montgomery County, MD, Prince George's County, MD

The radar

The Sterling radar (KLWX), 53 km from the middle of the area, began a volume at 22:20 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, 10.3 hours before the alert went out and 46 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-pSkew-T log-p diagram, Washington/Dulle, VA at 12:00Z on 2014-08-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 717 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Washington/Dulle, VA at 12:00Z on 2014-08-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 187 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
717 J/kg
Mixed-layer CIN
-75 J/kg
Mixed-layer LCL
833 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
187 m²/s²
0-3 km storm-relative helicity
154 m²/s²
Significant tornado parameter
0.4
Supercell composite
4.9

Open this sounding in Storm Lab

The office that day

Everything else NWS Baltimore/Washington issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 31, 1:38 PM EDTSmall Craft AdvisoryLWX9 hr
Aug 31, 4:35 PM EDTSevere Thunderstorm WarningLWXClarke, Fauquier, Loudoun, Rappahannock, Warren40 min
Aug 31, 5:09 PM EDTSevere Thunderstorm WarningLWXFauquier, Loudoun, Prince William51 min
Aug 31, 5:32 PM EDTSpecial Marine WarningLWX88 min
Aug 31, 5:45 PM EDTSevere Thunderstorm WarningLWXFairfax, Loudoun, City of Falls Church45 min
Aug 31, 6:07 PM EDTSevere Thunderstorm WarningLWXCulpeper, Fauquier, Prince William, Rappahannock38 min
Aug 31, 6:42 PM EDTSpecial Marine WarningLWX2 hr
Aug 31, 7:19 PM EDTSpecial Marine WarningLWX86 min
Aug 31, 7:35 PM EDTSmall Craft AdvisoryLWX3 hr
Aug 31, 2:39 PM EDTCoastal Flood AdvisoryLWXAnne Arundel9 hr

Nearby

Severe Thunderstorm Warnings in Maryland, 2014Every 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.