Alert archive / Virginia / Flood Watches in 2011

Flood Watch 2, NWS Baltimore/Washington

March 8, 201128 counties in Virginia; 11 counties in Maryland; 8 counties in West Virginia

NWS Baltimore/Washington issued this flood watch at Mar 8, 2011, 3:14 AM EST for 28 counties in Virginia; 11 counties in Maryland; 8 counties in West Virginia. It took effect at Mar 9, 2011, 12:00 PM EST. It was in force for 32 hr.

The area

The counties it named.

The facts

Issued: Mar 8, 2011, 3:14 AM EST (08:14 UTC)
In effect from: Mar 9, 2011, 12:00 PM EST
Expired: Mar 10, 2011, 7:56 PM EST
In force: 32 hr
Issued by: NWS Baltimore/Washington
Flood severity: None

All 47 counties

Allegany County, MD, Anne Arundel County, MD, Baltimore County, MD, Calvert County, MD, Carroll County, MD, Charles County, MD, City of Baltimore, MD, Frederick County, MD, Prince George's County, MD, Saint Mary's County, MD, Washington County, MD, Arlington County, VA, City of Alexandria, VA, City of Charlottesville, VA, City of Fairfax, VA, City of Falls Church, VA, City of Fredericksburg, VA, City of Harrisonburg, VA, City of Staunton, VA, City of Waynesboro, VA, City of Winchester, VA, Clarke County, VA, Culpeper County, VA, Fairfax County, VA, Fauquier County, VA, Frederick County, VA, Greene County, VA, Highland County, VA, King George County, VA, Madison County, VA, Nelson County, VA, Orange County, VA, Page County, VA, Rappahannock County, VA, Rockingham County, VA, Shenandoah County, VA, Spotsylvania County, VA, Stafford County, VA, Warren County, VA, Berkeley County, WV, Grant County, WV, Hampshire County, WV, Hardy County, WV, Jefferson County, WV, Mineral County, WV, Morgan County, WV, Pendleton County, WV

The radar

The Sterling radar (KLWX), 44 km from the middle of the area, began a volume at 08:20 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 00:00Z, 8.2 hours before the alert went out and 50 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 2388 m above ground
0-6 km bulk shear: 46 kt
0-1 km storm-relative helicity: -43 m²/s²
0-3 km storm-relative helicity: 40 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 flood watch 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 flood watch went out at Mar 7, 8:39 PM EST, 6 hours 35 minutes earlier.

Area forecast discussion, Mar 7, 8:39 PM EST, 6 hours 35 minutes before

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Hazardous weather outlook, Mar 7, 9:07 PM EST, 6 hours 7 minutes before

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<body>
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    <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.

Issued	Product	Office	Counties	Lasted
Mar 8, 2:57 PM EST	Small Craft Advisory	LWX		55 hr

Nearby

Flood Watches in Virginia, 2011 Flood Watches in Maryland, 2011 Flood Watches in West Virginia, 2011 Every flood watch in 2011

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.