Alert archive / Virginia / Winter Storm Warnings in 2017

Winter Storm Warning 4, NWS Baltimore/Washington

December 8, 20174 counties in Virginia; Calvert County, Charles County, Saint Mary's County, Maryland

NWS Baltimore/Washington issued this winter storm warning at Dec 8, 2017, 2:52 PM EST for 4 counties in Virginia; Calvert County, Charles County, Saint Mary's County, Maryland. It took effect at Dec 8, 2017, 7:00 PM EST. It was in force for 21 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
Dec 8, 2017, 2:52 PM EST (19:52 UTC)
In effect from
Dec 8, 2017, 7:00 PM EST
Expired
Dec 9, 2017, 4:08 PM EST
In force
21 hr
Issued by
NWS Baltimore/Washington

Counties Calvert County, MD, Charles County, MD, Saint Mary's County, MD, City of Fredericksburg, VA, King George County, VA, Spotsylvania County, VA, Stafford County, VA

The radar

The Sterling radar (KLWX), 77 km from the middle of the area, began a volume at 19:49 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, 7.9 hours before the alert went out and 72 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 2017-12-08Temperature 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, Washington/Dulle, VA at 12:00Z on 2017-12-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 44 square meters per square second.1939587897117136156175Sfc1 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
1723 m above ground
0-6 km bulk shear
96 kt
0-1 km storm-relative helicity
44 m²/s²
0-3 km storm-relative helicity
179 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 winter storm 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 winter storm warning went out at Dec 8, 10:07 AM EST, 4 hours 45 minutes earlier.

Area forecast discussion, Dec 8, 10:07 AM EST, 4 hours 45 minutes before
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Hazardous weather outlook, Dec 8, 9:41 AM EST, 5 hours 11 minutes before
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<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
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        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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The office that day

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

IssuedProductOfficeCountiesLasted
Dec 7, 8:24 PM ESTSmall Craft AdvisoryLWX7 hr
Dec 8, 5:50 AM ESTWinter Weather AdvisoryLWXAlbemarle, Amherst, Arlington, Augusta, Culpeper, Fairfax and 23 more51 hr
Dec 8, 11:10 AM ESTSmall Craft AdvisoryLWX67 hr
Dec 8, 11:10 AM ESTSmall Craft AdvisoryLWX53 hr

Nearby

Winter Storm Warnings in Virginia, 2017Winter Storm Warnings in Maryland, 2017Every winter storm 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.