Alert archive / Maryland / Flash Flood Warnings in 2018

Flash Flood Warning 56, NWS Baltimore/Washington

July 23, 2018Baltimore County, Carroll County, Maryland

NWS Baltimore/Washington issued this flash flood warning at Jul 23, 2018, 10:34 PM EDT for Baltimore County, Carroll 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
Jul 23, 2018, 10:34 PM EDT (02:34 UTC)
Expired
Jul 24, 2018, 1:30 AM EDT
In force
3 hr
Issued by
NWS Baltimore/Washington
Area
Storm-based polygon
Flood severity
None

Counties Baltimore County, MD, Carroll County, MD

The radar

The Sterling radar (KLWX), 82 km from the middle of the area, began a volume at 02:37 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, 2.6 hours before the alert went out and 79 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, Washington/Dulle, VA at 00:00Z on 2018-07-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 791 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, Washington/Dulle, VA at 00:00Z on 2018-07-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 115 square meters per square second.193958Sfc1 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
791 J/kg
Mixed-layer CIN
-4 J/kg
Mixed-layer LCL
722 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
115 m²/s²
0-3 km storm-relative helicity
141 m²/s²
Significant tornado parameter
0.4
Supercell composite
4.2

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 23, 8:37 PM EDT, 1 hour 57 minutes earlier.

Area forecast discussion, Jul 23, 8:37 PM EDT, 1 hour 57 minutes before
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Hazardous weather outlook, Jul 23, 7:39 PM EDT, 2 hours 55 minutes before
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In the hours before

Local storm report, Jul 23, 9:32 PM EDT, 1 hour 2 minutes before
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Local storm report, Jul 23, 10:14 PM EDT, 20 minutes before
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Local storm report, Jul 23, 10:29 PM EDT, 5 minutes before
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      <h1 id="headline">This service is currently unavailable.</h1>
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The office that day

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

IssuedProductOfficeCountiesLasted
Jul 24, 5:54 AM EDTTornado WarningLWXFairfax21 min
Jul 24, 6:14 AM EDTAreal Flood WarningLWXFairfax, Loudoun, Prince William, City of Fairfax, City of Falls Church8 hr
Jul 24, 9:27 AM EDTSpecial Marine WarningLWX93 min
Jul 24, 10:22 AM EDTSpecial Marine WarningLWX38 min
Jul 24, 10:59 AM EDTSpecial Marine WarningLWX61 min
Jul 23, 8:11 PM EDTCoastal Flood AdvisoryLWXAnne Arundel, Harford35 hr
Jul 23, 8:47 PM EDTAreal Flood WarningLWXAnne Arundel, Baltimore, Carroll, Howard6 hr
Jul 23, 9:22 PM EDTAreal Flood WarningLWXAnne Arundel, Baltimore, Carroll, City of Baltimore6 hr
Jul 24, 3:23 AM EDTAreal Flood WarningLWXBaltimore, City of Baltimore43 hr
Jul 24, 8:10 AM EDTAreal Flood WarningLWXAnne Arundel, Calvert, Charles, Prince George's, Saint Mary's15 hr
Jul 24, 9:05 AM EDTAreal Flood WarningLWXAnne Arundel, Baltimore, Howard, Prince George's6 hr
Jul 24, 10:20 AM EDTRiver Flood WarningLWXWashington54 hr
Jul 24, 10:21 AM EDTRiver Flood WarningLWXWashington39 hr
Jul 24, 11:18 AM EDTAreal Flood WarningLWXBaltimore, Harford, City of Baltimore21 hr
Jul 24, 2:58 PM EDTCoastal Flood AdvisoryLWXHarford21 hr
Jul 24, 3:19 PM EDTAreal Flood WarningLWXAnne Arundel, Baltimore, Howard23 hr
Jul 24, 7:12 PM EDTAreal Flood WarningLWXAllegany6 hr
Jul 24, 7:16 PM EDTCoastal Flood AdvisoryLWXCalvert7 hr

Nearby

Flash Flood Warnings in Maryland, 2018Every flash flood warning in 2018

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.