Alert archive / Virginia / Flash Flood Warnings in 2015

Flash Flood Warning 19, NWS Baltimore/Washington

June 27, 201510 counties in Virginia; Montgomery County, Prince George's County, Maryland

NWS Baltimore/Washington issued this flash flood warning at Jun 27, 2015, 2:38 PM EDT for 10 counties in Virginia; Montgomery County, Prince George's County, Maryland. 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: Jun 27, 2015, 2:38 PM EDT (18:38 UTC)
Expired: Jun 27, 2015, 5:30 PM EDT
In force: 3 hr
Issued by: NWS Baltimore/Washington
Area: Storm-based polygon
Flood severity: None

Counties Montgomery County, MD, Prince George's County, MD, Arlington County, VA, City of Alexandria, VA, City of Fairfax, VA, City of Falls Church, VA, City of Manassas, VA, City of Manassas Park, VA, Fairfax County, VA, Loudoun County, VA, Prince William County, VA, Stafford County, VA

The radar

The Sterling radar (KLWX), 24 km from the middle of the area, began a volume at 18:39 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, 6.6 hours before the alert went out and 16 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: 603 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: 153 m²/s²
0-3 km storm-relative helicity: 202 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 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 Jun 27, 10:38 AM EDT, 4 hours earlier.

Area forecast discussion, Jun 27, 10:38 AM EDT, 4 hours before

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Hazardous weather outlook, Jun 27, 2:05 PM EDT, 33 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 26, 10:42 PM EDT	Severe Thunderstorm Warning	LWX	Highland	48 min
Jun 27, 12:01 PM EDT	Coastal Flood Advisory	LWX	Arlington, City of Alexandria, City of Falls Church	20 hr
Jun 27, 2:49 PM EDT	Special Marine Warning	LWX		116 min
Jun 27, 2:55 PM EDT	Severe Thunderstorm Warning	LWX	Spotsylvania, Stafford, City of Fredericksburg	50 min
Jun 27, 3:09 PM EDT	Special Marine Warning	LWX		51 min
Jun 27, 3:14 PM EDT	Severe Thunderstorm Warning	LWX	Fairfax, Prince William	31 min
Jun 27, 3:39 PM EDT	Tornado Warning	LWX	Stafford	13 min
Jun 27, 3:46 PM EDT	Special Marine Warning	LWX		119 min
Jun 27, 3:56 PM EDT	Special Marine Warning	LWX		64 min
Jun 27, 3:59 PM EDT	Tornado Warning	LWX	King George	31 min
Jun 27, 4:06 PM EDT	Flash Flood Warning	LWX	King George, Spotsylvania, Stafford, City of Fredericksburg	3 hr
Jun 27, 4:51 PM EDT	Special Marine Warning	LWX		84 min
Jun 27, 5:16 PM EDT	Special Marine Warning	LWX		89 min
Jun 27, 9:04 AM EDT	Coastal Flood Advisory	LWX	Anne Arundel	22 hr
Jun 27, 3:52 PM EDT	Flash Flood Warning	LWX	Carroll, Frederick, Howard, Montgomery	83 min
Jun 27, 4:25 PM EDT	Flash Flood Warning	LWX	Baltimore, Carroll, Howard, Montgomery	3 hr
Jun 27, 4:27 PM EDT	Tornado Warning	LWX	Charles, Saint Mary's	33 min
Jun 27, 4:31 PM EDT	River Flood Warning	LWX	Montgomery	25 hr
Jun 27, 4:52 PM EDT	Flash Flood Warning	LWX	Charles, Saint Mary's	3 hr
Jun 27, 4:52 PM EDT	Tornado Warning	LWX	Calvert, Saint Mary's	38 min
Jun 27, 5:04 PM EDT	Flash Flood Warning	LWX	Anne Arundel, Prince George's	3 hr
Jun 27, 5:06 PM EDT	Flash Flood Warning	LWX	Baltimore, Harford, City of Baltimore	3 hr
Jun 27, 5:20 PM EDT	Areal Flood Warning	LWX	Howard, Montgomery	11 hr
Jun 27, 5:38 PM EDT	Flash Flood Warning	LWX	Anne Arundel, Baltimore, City of Baltimore	3 hr
Jun 27, 6:51 PM EDT	Areal Flood Warning	LWX	Montgomery, Prince George's	7 hr
Jun 27, 7:32 PM EDT	Areal Flood Warning	LWX	Charles, Saint Mary's	118 min
Jun 27, 7:55 PM EDT	Areal Flood Warning	LWX	Anne Arundel, Baltimore, Harford, Howard, Montgomery, Prince George's and 1 more	7 hr

Nearby

Flash Flood Warnings in Virginia, 2015 Flash Flood Warnings in Maryland, 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.