Alert archive / Maryland / Severe Thunderstorm Warnings in 2013

Severe Thunderstorm Warning 7, NWS Baltimore/Washington

April 12, 20134 counties in Maryland

NWS Baltimore/Washington issued this severe thunderstorm warning at Apr 12, 2013, 7:04 PM EDT for 4 counties in Maryland. It was in force for 41 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 12, 2013, 7:04 PM EDT (23:04 UTC)
Expired
Apr 12, 2013, 7:45 PM EDT
In force
41 min
Issued by
NWS Baltimore/Washington
Area
Storm-based polygon

Counties Carroll County, MD, Frederick County, MD, Howard County, MD, Montgomery County, MD

The radar

The Sterling radar (KLWX), 52 km from the middle of the area, began a volume at 23:07 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

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 11.1 hours before the alert went out and 90 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, Phillips Aaf/Abe, MD at 12:00Z on 2013-04-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 6 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Phillips Aaf/Abe, MD at 12:00Z on 2013-04-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 439 square meters per square second.19395878Sfc1 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
6 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
416 m above ground
0-6 km bulk shear
69 kt
0-1 km storm-relative helicity
439 m²/s²
0-3 km storm-relative helicity
512 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 12, 3:57 AM EDTSmall Craft AdvisoryLWX25 hr
Apr 12, 7:26 AM EDTSpecial Marine WarningLWX49 min
Apr 12, 8:14 AM EDTSpecial Marine WarningLWX61 min
Apr 12, 1:43 PM EDTSpecial Marine WarningLWX92 min
Apr 12, 2:09 PM EDTSpecial Marine WarningLWX96 min
Apr 12, 6:19 PM EDTSpecial Marine WarningLWX86 min
Apr 11, 9:52 PM EDTCoastal Flood AdvisoryLWXAnne Arundel11 hr
Apr 12, 1:46 PM EDTCoastal Flood AdvisoryLWXAnne Arundel8 hr
Apr 12, 2:42 PM EDTSpecial Weather StatementLWXCalvert18 min
Apr 12, 6:12 PM EDTSpecial Weather StatementLWXFrederick18 min
Apr 12, 6:36 PM EDTSpecial Weather StatementLWXCarroll24 min
Apr 12, 6:51 PM EDTSevere Thunderstorm WarningLWXCarroll, Frederick, Howard, Montgomery39 min
Apr 12, 7:00 PM EDTSpecial Weather StatementLWXFrederick15 min
Apr 12, 7:14 PM EDTSpecial Weather StatementLWXBaltimore31 min
Apr 12, 7:25 PM EDTSpecial Weather StatementLWXBaltimore35 min
Apr 12, 7:45 PM EDTSpecial Weather StatementLWXBaltimore, Howard30 min

Nearby

Severe Thunderstorm Warnings in Maryland, 2013Every severe thunderstorm warning in 2013

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.