Alert archive / Maryland / River Flood Warnings in 2008

River Flood Warning 9, NWS Baltimore/Washington

April 21, 2008Montgomery County, Maryland

NWS Baltimore/Washington issued this river flood warning at Apr 21, 2008, 10:15 AM EDT for Montgomery County, Maryland. It took effect at Apr 21, 2008, 7:00 PM EDT. It was in force for .

The area

The counties it named.

The facts

Issued: Apr 21, 2008, 10:15 AM EDT (14:15 UTC)
In effect from: Apr 21, 2008, 7:00 PM EDT
Expired: Apr 21, 2008, 3:54 PM EDT
In force
Issued by: NWS Baltimore/Washington
Flood severity: Minor

County Montgomery County, MD

The radar

The Sterling radar (KLWX), 30 km from the middle of the area, began a volume at 14:18 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 river

Written for the forecast point Seneca Creek at Dawsonville (DAWM2). The gauge peaked at 6.94 ft at Apr 21, 2008, 5:00 AM EDT.

Action stage: 5 ft
Minor stage: 7.5 ft
Moderate stage: 11 ft
Major stage: 16 ft

This gauge today: stage, forecast and historic crests

Stage from the USGS instantaneous record for site 01645000, one reading an hour, from a day before the product to a day after it ended. Flood stages are today's.

What forecasters said that day

The local office's own words before this river 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 river flood warning went out at Apr 21, 9:57 AM EDT, 18 minutes earlier.

Area forecast discussion, Apr 21, 9:57 AM EDT, 18 minutes before

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Hazardous weather outlook, Apr 21, 5:54 AM EDT, 4 hours 21 minutes before

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In the hours before

Local storm report, Apr 21, 8:48 AM EDT, 1 hour 27 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
Apr 20, 8:43 PM EDT	Coastal Flood Advisory	LWX	Arlington, Fairfax, King George, Stafford, City of Alexandria, City of Fairfax and 1 more	15 hr
Apr 20, 10:06 PM EDT	Tornado Warning	LWX	Frederick, Shenandoah	39 min
Apr 20, 11:59 PM EDT	Areal Flood Warning	LWX	Fairfax, Loudoun, City of Fairfax	6 hr
Apr 21, 12:40 AM EDT	Special Marine Warning	LWX		50 min
Apr 21, 12:41 AM EDT	Areal Flood Warning	LWX	Fauquier	5 hr
Apr 21, 12:08 PM EDT	Coastal Flood Advisory	LWX	Arlington, Fairfax, King George, Stafford, City of Alexandria, City of Fairfax and 1 more	48 hr
Apr 20, 9:06 PM EDT	Areal Flood Warning	LWX	Frederick	6 hr
Apr 21, 12:46 AM EDT	Severe Thunderstorm Warning	LWX	Calvert	24 min
Apr 21, 3:57 AM EDT	River Flood Warning	LWX	Montgomery	6 hr

Nearby

River Flood Warnings in Maryland, 2008 Every river flood warning in 2008

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; radar from the NEXRAD Level II archive; the gauge from the NWS water service and the USGS.