Alert archive / Maryland / Flash Flood Warnings in 2011

Flash Flood Warning 104, NWS Baltimore/Washington

August 15, 2011Anne Arundel County, Baltimore County, City of Baltimore, Maryland

NWS Baltimore/Washington issued this flash flood warning at Aug 15, 2011, 8:01 AM EDT for Anne Arundel County, Baltimore County, City of Baltimore, 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
Aug 15, 2011, 8:01 AM EDT (12:01 UTC)
Expired
Aug 15, 2011, 10:31 AM EDT
In force
3 hr
Issued by
NWS Baltimore/Washington
Area
Storm-based polygon
Flood severity
None

Counties Anne Arundel County, MD, Baltimore County, MD, City of Baltimore, MD

The radar

The Sterling radar (KLWX), 82 km from the middle of the area, began a volume at 12:03 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

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 0.0 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-pSkew-T log-p diagram, Phillips Aaf/Abe, MD at 12:00Z on 2011-08-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 460 joules per kilogram.LCLLFCEL10008507005003002001001 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, Phillips Aaf/Abe, MD at 12:00Z on 2011-08-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 7 square meters per square second.1939587897Sfc1 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
460 J/kg
Mixed-layer CIN
-20 J/kg
Mixed-layer LCL
689 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
7 m²/s²
0-3 km storm-relative helicity
31 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.3

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 Aug 15, 3:22 AM EDT, 4 hours 39 minutes earlier.

Area forecast discussion, Aug 15, 3:22 AM EDT, 4 hours 39 minutes before
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Hazardous weather outlook, Aug 15, 4:30 AM EDT, 3 hours 31 minutes before
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In the hours before

Local storm report, Aug 15, 2:24 AM EDT, 5 hours 37 minutes before
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Local storm report, Aug 15, 2:53 AM EDT, 5 hours 8 minutes before
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Local storm report, Aug 15, 2:57 AM EDT, 5 hours 4 minutes before
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Local storm report, Aug 15, 3:15 AM EDT, 4 hours 46 minutes before
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Special weather statement, Aug 15, 7:51 AM EDT, 10 minutes before
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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
Aug 14, 8:13 PM EDTSpecial Marine WarningLWX92 min
Aug 14, 8:18 PM EDTSpecial Weather StatementLWXKing George, City of Fredericksburg42 min
Aug 14, 8:19 PM EDTSpecial Marine WarningLWX86 min
Aug 14, 8:33 PM EDTSpecial Weather StatementLWX27 min
Aug 14, 8:55 PM EDTSpecial Weather StatementLWX50 min
Aug 14, 9:15 PM EDTSevere Thunderstorm WarningLWXFairfax, Loudoun22 min
Aug 14, 9:43 PM EDTSpecial Marine WarningLWX2 hr
Aug 14, 9:51 PM EDTSpecial Marine WarningLWX84 min
Aug 14, 10:21 PM EDTSpecial Weather StatementLWXArlington, City of Alexandria54 min
Aug 14, 10:32 PM EDTAreal Flood WarningLWXAlbemarle, Nelson, City of Charlottesville3 hr
Aug 14, 11:08 PM EDTSpecial Marine WarningLWX97 min
Aug 15, 12:40 AM EDTSpecial Marine WarningLWX58 min
Aug 15, 1:09 AM EDTCoastal Flood AdvisoryLWXArlington, Fairfax, King George, Stafford, City of Alexandria, City of Fairfax and 1 more9 hr
Aug 15, 8:18 AM EDTSpecial Marine WarningLWX57 min
Aug 15, 12:47 PM EDTSpecial Weather StatementLWXCity of Harrisonburg28 min
Aug 15, 4:42 PM EDTSpecial Marine WarningLWX68 min
Aug 15, 5:17 PM EDTSpecial Marine WarningLWX88 min
Aug 15, 6:14 PM EDTSpecial Marine WarningLWX57 min
Aug 14, 8:29 PM EDTSpecial Weather StatementLWXMontgomery31 min
Aug 14, 9:02 PM EDTSpecial Weather StatementLWXMontgomery28 min
Aug 14, 9:23 PM EDTFlash Flood WarningLWXMontgomery, Prince George's3 hr
Aug 14, 9:36 PM EDTSpecial Weather StatementLWXHoward, Montgomery54 min
Aug 14, 9:54 PM EDTFlash Flood WarningLWXFrederick, Montgomery3 hr
Aug 14, 10:18 PM EDTSpecial Weather StatementLWXCarroll42 min
Aug 14, 10:49 PM EDTSpecial Weather StatementLWXBaltimore, City of Baltimore56 min
Aug 14, 11:27 PM EDTFlash Flood WarningLWXBaltimore, Carroll, Howard, City of Baltimore77 min
Aug 15, 7:51 AM EDTSpecial Weather StatementLWXCity of Baltimore39 min
Aug 15, 9:23 AM EDTFlash Flood WarningLWXBaltimore, City of Baltimore3 hr
Aug 15, 9:36 AM EDTSpecial Weather StatementLWXCity of Baltimore24 min
Aug 15, 12:10 PM EDTFlash Flood WatchLWXBaltimore, Carroll, City of Baltimore6 hr
Aug 15, 1:10 PM EDTFlash Flood WarningLWXBaltimore, City of Baltimore118 min
Aug 15, 3:49 PM EDTSpecial Weather StatementLWXCalvert26 min
Aug 15, 3:53 PM EDTSpecial Weather StatementLWXPrince George's37 min
Aug 15, 4:12 PM EDTSpecial Weather StatementLWXPrince George's33 min
Aug 15, 4:28 PM EDTSpecial Weather StatementLWXSaint Mary's32 min
Aug 15, 4:33 PM EDTFlash Flood WarningLWXPrince George's80 min
Aug 14, 8:15 PM EDTSpecial Weather StatementLWXMineral30 min
Aug 15, 1:01 PM EDTSpecial Weather StatementLWXHardy29 min

Nearby

Flash Flood Warnings in Maryland, 2011Every flash flood warning 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.