Alert archive / Virginia / Flash Flood Warnings in 2015

Flash Flood Warning 31, NWS Baltimore/Washington

July 5, 20154 counties in Virginia

NWS Baltimore/Washington issued this flash flood warning at Jul 5, 2015, 10:42 PM EDT for 4 counties in Virginia. It was in force for 3 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: Jul 5, 2015, 10:42 PM EDT (02:42 UTC)
Expired: Jul 6, 2015, 1:45 AM EDT
In force: 3 hr
Issued by: NWS Baltimore/Washington
Area: Storm-based polygon
Flood severity: None

Counties Culpeper County, VA, Madison County, VA, Page County, VA, Rappahannock County, VA

The radar

The Sterling radar (KLWX), 79 km from the middle of the area, began a volume at 02:45 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

Roanoke, VA (KRNK), launched 00:00Z, 2.7 hours before the alert went out and 188 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: 186 J/kg
Mixed-layer CIN: -30 J/kg
Mixed-layer LCL: 920 m above ground
0-6 km bulk shear: 43 kt
0-1 km storm-relative helicity: 97 m²/s²
0-3 km storm-relative helicity: 130 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 1.9

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood 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 flash flood warning went out at Jul 5, 9:04 PM EDT, 1 hour 38 minutes earlier.

Area forecast discussion, Jul 5, 9:04 PM EDT, 1 hour 38 minutes before

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Hazardous weather outlook, Jul 5, 10:03 PM EDT, 39 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>
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        The site you requested is temporarily down for maintenance or an unexpected outage.
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        Please try again in a few minutes.
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The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 6, 7:01 PM EDT	Special Marine Warning	LWX		89 min
Jul 6, 7:32 PM EDT	Special Marine Warning	LWX		88 min
Jul 6, 7:15 PM EDT	Flash Flood Warning	LWX	Baltimore, Carroll, Howard	4 hr

Nearby

Flash Flood Warnings in Virginia, 2015 Every flash flood 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.