Alert archive / Virginia / Freeze Warnings in 2012

Freeze Warning 7, NWS Baltimore/Washington

April 9, 20125 counties in Virginia; Allegany County, Maryland; 5 counties in West Virginia

NWS Baltimore/Washington issued this freeze warning at Apr 9, 2012, 2:32 PM EDT for 5 counties in Virginia; Allegany County, Maryland; 5 counties in West Virginia. It took effect at Apr 10, 2012, 2:00 AM EDT. It was in force for 6 hr. 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 9, 2012, 2:32 PM EDT (18:32 UTC)
In effect from
Apr 10, 2012, 2:00 AM EDT
Expired
Apr 10, 2012, 7:34 AM EDT
In force
6 hr
Issued by
NWS Baltimore/Washington

Counties Allegany County, MD, City of Harrisonburg, VA, City of Staunton, VA, City of Waynesboro, VA, Highland County, VA, Rockingham County, VA, Grant County, WV, Hampshire County, WV, Hardy County, WV, Mineral County, WV, Pendleton County, WV

The radar

The Sterling radar (KLWX), 132 km from the middle of the area, began a volume at 18:35 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

Pittsburgh, PA (KPIT), launched 12:00Z, 6.5 hours before the alert went out and 204 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, Pittsburgh, PA at 12:00Z on 2012-04-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Pittsburgh, PA at 12:00Z on 2012-04-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 102 square meters per square second.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1202 m above ground
0-6 km bulk shear
62 kt
0-1 km storm-relative helicity
102 m²/s²
0-3 km storm-relative helicity
233 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 freeze 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 freeze warning went out at Apr 9, 12:30 PM EDT, 2 hours 2 minutes earlier.

Area forecast discussion, Apr 9, 12:30 PM EDT, 2 hours 2 minutes before
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Hazardous weather outlook, Apr 9, 12:39 PM EDT, 1 hour 53 minutes before
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      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
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        The site you requested is temporarily down for maintenance or an unexpected outage.
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The office that day

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

IssuedProductOfficeCountiesLasted
Apr 8, 8:19 PM EDTRed Flag WarningLWXAlbemarle, Arlington, Augusta, Clarke, Culpeper, Fairfax and 21 more23 hr
Apr 8, 11:05 PM EDTSmall Craft AdvisoryLWX19 hr
Apr 9, 3:45 AM EDTFreeze WatchLWXHighland11 hr
Apr 9, 10:34 AM EDTFire Weather WatchLWXAlbemarle, Arlington, Augusta, Clarke, Culpeper, Fairfax and 21 more10 hr
Apr 9, 12:37 PM EDTGale WarningLWX7 hr
Apr 9, 12:37 PM EDTSmall Craft AdvisoryLWX5 hr
Apr 9, 2:32 PM EDTFreeze WatchLWXHighland, Rockingham, City of Harrisonburg, City of Staunton, City of Waynesboro13 hr
Apr 9, 5:40 PM EDTSmall Craft AdvisoryLWX44 hr
Apr 9, 7:47 PM EDTSmall Craft AdvisoryLWX42 hr

Nearby

Freeze Warnings in Virginia, 2012Freeze Warnings in West Virginia, 2012Freeze Warnings in Maryland, 2012Every freeze warning in 2012

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.