Alert archive / Maryland / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 232, NWS Baltimore/Washington

September 12, 2015Saint Mary's County, Maryland

NWS Baltimore/Washington issued this severe thunderstorm warning at Sep 12, 2015, 10:45 AM EDT for Saint Mary's County, Maryland. It was in force for 45 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 12, 2015, 10:45 AM EDT (14:45 UTC)
Expired
Sep 12, 2015, 11:30 AM EDT
In force
45 min
Issued by
NWS Baltimore/Washington
Area
Storm-based polygon

County Saint Mary's County, MD

The radar

The Dover AFB radar (KDOX), 116 km from the middle of the area, began a volume at 14:46 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 12:00Z, 2.8 hours before the alert went out and 104 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, Wallops Is Stn, VA at 12:00Z on 2015-09-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 104 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, Wallops Is Stn, VA at 12:00Z on 2015-09-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 38 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
104 J/kg
Mixed-layer CIN
-40 J/kg
Mixed-layer LCL
857 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
38 m²/s²
0-3 km storm-relative helicity
98 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 12, 1:55 AM EDTSmall Craft AdvisoryLWX5 hr
Sep 12, 1:55 AM EDTSmall Craft AdvisoryLWX42 hr
Sep 12, 9:25 AM EDTSmall Craft AdvisoryLWX9 hr
Sep 12, 9:30 AM EDTSpecial Marine WarningLWX90 min
Sep 12, 10:17 AM EDTSpecial Marine WarningLWX88 min
Sep 12, 10:53 AM EDTSpecial Marine WarningLWX82 min
Sep 12, 11:41 AM EDTCoastal Flood AdvisoryLWXArlington, City of Alexandria, City of Falls Church10 hr
Sep 12, 12:14 PM EDTSpecial Marine WarningLWX61 min
Sep 12, 2:29 PM EDTSpecial Marine WarningLWX61 min
Sep 12, 2:37 PM EDTSpecial Marine WarningLWX113 min
Sep 12, 2:51 PM EDTSpecial Marine WarningLWX84 min
Sep 12, 2:54 PM EDTSpecial Marine WarningLWX96 min
Sep 12, 3:14 PM EDTSpecial Marine WarningLWX2 hr
Sep 12, 3:55 PM EDTSpecial Marine WarningLWX95 min
Sep 12, 4:25 PM EDTSpecial Marine WarningLWX95 min
Sep 12, 7:57 PM EDTSmall Craft AdvisoryLWX47 hr

Nearby

Severe Thunderstorm Warnings in Maryland, 2015Every 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.