Alert archive / West Virginia / Flash Flood Warnings in 2021

Flash Flood Warning 64, NWS Baltimore/Washington

September 1, 2021Grant County, Mineral County, West Virginia; Allegany County, Garrett County, Maryland

NWS Baltimore/Washington issued this flash flood warning at Sep 1, 2021, 8:39 AM EDT for Grant County, Mineral County, West Virginia; Allegany County, Garrett County, Maryland. It was in force for 5 hr. 6 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Sep 1, 2021, 8:39 AM EDT (12:39 UTC)
Expired
Sep 1, 2021, 1:46 PM EDT
In force
5 hr
Issued by
NWS Baltimore/Washington
Area
Storm-based polygon
Flood severity
None

Counties Allegany County, MD, Garrett County, MD, Grant County, WV, Mineral County, WV

The radar

The Pittsburgh radar (KPBZ), 162 km from the middle of the area, began a volume at 12:40 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.

What was reported inside it

TimeReportWhereRemark
Sep 1, 12:15 PM EDTFLOOD4 Sse Mc Henry, MDGLENDALE ROAD AT ZEDDOCK MILLER ROAD CLOSED DUE TO STANDING HIGH WATER.
Sep 1, 12:15 PM EDTFLOOD4 Wnw Mc Henry, MDSANG RUN ROAD AT OAKLAND SANG RUN ROAD CLOSED DUE TO HIGH WATER.
Sep 1, 12:15 PM EDTFLOODFrostburg, MDSEVERAL ROADS CLOSED DUE TO FLOODING.
Sep 1, 12:15 PM EDTFLOODMount Savage, MDSEVERAL ROADS CLOSED IN/NEAR MOUNT SAVAGE DUE TO HIGH WATER.
Sep 1, 12:47 PM EDTFLOOD1 Sw Mount Savage, MDMD-36 MOUNT SAVAGE ROAD NORTHWEST WAS CLOSED IN BOTH DIRECTIONS DUE TO FLOODING AT JENNINGS RUN NEAR MD-638 PARKERSBURG ROAD NORTHWEST.
Sep 1, 1:05 PM EDTFLASH FLOODMidland, MD5 REPORTS OF ROADS CLOSED IN WESTERN ALLEGANY COUNTY, MAINLY NEAR GEORGES CREEK AND MOUNT SAVAGE. 1 SWIFT WATER RESCUE OF INDIVIDUAL CAUGHT IN FLOOD WATERS. THEY WERE FOUND. GEORGES CREEK EXPECTED TO BEGIN FLOODING IN MIDLAND ITSELF WITHIN 10 MINS. GEORGES CRE

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Pittsburgh, PA (KPIT), launched 12:00Z, 0.7 hours before the alert went out and 145 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, Pittsburgh, PA at 12:00Z on 2021-09-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Pittsburgh, PA at 12:00Z on 2021-09-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -93 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
666 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
-93 m²/s²
0-3 km storm-relative helicity
-7 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

315 
WGUS51 KLWX 011239
FFWLWX
MDC001-023-WVC023-057-011800-
/O.NEW.KLWX.FF.W.0064.210901T1239Z-210901T1800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Baltimore MD/Washington DC
839 AM EDT Wed Sep 1 2021

The National Weather Service in Sterling Virginia has issued a

* Flash Flood Warning for...
  Western Allegany County in western Maryland...
  Garrett County in western Maryland...
  Northwestern Grant County in eastern West Virginia...
  Southwestern Mineral County in eastern West Virginia...

* Until 200 PM EDT.

* At 839 AM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. The expected rainfall rate is 1 
  to 3 inches in 1 hour. Flash flooding is ongoing or expected to 
  begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Please report observed flooding to local emergency services or law 
enforcement and request they pass this information to the National 
Weather Service when you can do so safely.

&&

LAT...LON 3972 7948 3972 7875 3897 7933 3898 7934
      3907 7930 3909 7936 3912 7933 3915 7933
      3920 7930 3921 7931 3921 7934 3920 7936
      3920 7938 3919 7940 3919 7944 3918 7947
      3919 7949

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-3 INCHES IN 1 HOUR

$$

CS
2 follow-up statements
420 
WGUS71 KLWX 011700
FFSLWX

Flash Flood Statement
National Weather Service Baltimore MD/Washington DC
100 PM EDT Wed Sep 1 2021

MDC001-023-WVC023-057-011800-
/O.CON.KLWX.FF.W.0064.000000T0000Z-210901T1800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Allegany MD-Garrett MD-Grant WV-Mineral WV-
100 PM EDT Wed Sep 1 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 2 PM EDT THIS 
AFTERNOON FOR WESTERN ALLEGANY, GARRETT, NORTHWESTERN GRANT AND 
SOUTHWESTERN MINERAL COUNTIES...

At 100 PM EDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 2 and 3 inches of rain have 
fallen. Additional rainfall amounts of 1 to 3 inches are possible in 
the warned area. Flash flooding is already occurring.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar and observations.

IMPACT...Flash flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other poor
         drainage and low-lying areas.

This includes some of the following Flood Prone areas:
Midland near Georges Creek...
Lonaconing near Georges Creek and Koontz Run...


PRECAUTIONARY/PREPAREDNESS ACTIONS...

Those along any streams or creeks in this warning should closely 
monitor river levels and SEEK HIGHER GROUND IF NECESSARY. They may 
rise quickly.


Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Please report observed flooding to local emergency services or law 
enforcement and request they pass this information to the National 
Weather Service when you can do so safely.

&&

LAT...LON 3972 7948 3972 7875 3897 7933 3898 7934
      3907 7930 3909 7936 3912 7933 3915 7933
      3920 7930 3921 7931 3921 7934 3920 7936
      3920 7938 3919 7940 3919 7944 3918 7947
      3919 7949

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-3 INCHES IN 1 HOUR

$$

CS
295 
WGUS71 KLWX 011746
FFSLWX

Flash Flood Statement
National Weather Service Baltimore MD/Washington DC
146 PM EDT Wed Sep 1 2021

MDC001-023-WVC023-057-011756-
/O.CAN.KLWX.FF.W.0064.000000T0000Z-210901T1800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Allegany MD-Garrett MD-Grant WV-Mineral WV-
146 PM EDT Wed Sep 1 2021

...FLASH FLOOD WARNING FOR WESTERN ALLEGANY, GARRETT, NORTHWESTERN 
GRANT AND SOUTHWESTERN MINERAL COUNTIES HAS BEEN REPLACED WITH A 
FLOOD WARNING...

The heavy rain has ended. Flooding is no longer expected to pose a 
significant threat. Please continue to heed remaining road closures.

A Flash Flood Watch remains in effect until 200 AM EDT Thursday for 
portions of Maryland, Virginia and West Virginia.

LAT...LON 3972 7948 3972 7875 3897 7933 3898 7934
      3907 7930 3909 7936 3912 7933 3915 7933
      3920 7930 3921 7931 3921 7934 3920 7936
      3920 7938 3919 7940 3919 7944 3918 7947
      3919 7949

$$

BKF

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 31, 9:44 PM EDTRiver Flood WatchLWXJefferson25 hr
Sep 1, 12:52 PM EDTAreal Flood WarningLWXHampshire, Mineral22 hr
Sep 1, 1:30 PM EDTAreal Flood WarningLWXBerkeley, Jefferson, Morgan27 hr
Sep 1, 1:46 PM EDTAreal Flood WarningLWXGrant, Mineral16 hr
Sep 1, 3:36 PM EDTWind AdvisoryLWXBerkeley, Morgan7 hr
Aug 31, 9:06 PM EDTCoastal Flood WatchLWXAnne Arundel22 hr
Aug 31, 9:36 PM EDTRiver Flood WarningLWXWashington68 hr
Aug 31, 9:44 PM EDTRiver Flood WatchLWXFrederick25 hr
Aug 31, 9:44 PM EDTRiver Flood WatchLWXMontgomery48 hr
Aug 31, 9:44 PM EDTRiver Flood WatchLWXMontgomery25 hr
Sep 1, 3:23 AM EDTAreal Flood WarningLWXMontgomery8 hr
Sep 1, 3:24 AM EDTSevere Thunderstorm WarningLWXMontgomery, Prince George's51 min
Sep 1, 3:50 AM EDTAreal Flood WarningLWXMontgomery, Prince George's6 hr
Sep 1, 4:00 AM EDTSevere Thunderstorm WarningLWXAnne Arundel, Prince George's60 min
Sep 1, 4:10 AM EDTAreal Flood WarningLWXAnne Arundel, Baltimore, Howard, City of Baltimore6 hr
Sep 1, 4:34 AM EDTAreal Flood WarningLWXMontgomery6 hr
Sep 1, 4:39 AM EDTAreal Flood WarningLWXAnne Arundel, Baltimore, Howard, City of Baltimore5 hr
Sep 1, 4:50 AM EDTSevere Thunderstorm WarningLWXAnne Arundel, Baltimore, City of Baltimore40 min
Sep 1, 5:41 AM EDTAreal Flood WarningLWXCecil, Harford5 hr
Sep 1, 6:15 AM EDTAreal Flood WarningLWXCecil5 hr
Sep 1, 10:14 AM EDTCoastal Flood AdvisoryLWXAnne Arundel, Baltimore, Calvert, Cecil, Harford, Saint Mary's and 1 more19 hr
Sep 1, 1:11 PM EDTTornado WarningLWXCharles, Prince George's34 min
Sep 1, 1:23 PM EDTTornado WarningLWXCharles17 min
Sep 1, 1:31 PM EDTTornado WarningLWXCharles, Saint Mary's29 min
Sep 1, 1:56 PM EDTTornado WarningLWXAnne Arundel, Prince George's34 min
Sep 1, 2:12 PM EDTTornado WarningLWXBaltimore33 min
Sep 1, 2:23 PM EDTTornado WarningLWXBaltimore15 min
Sep 1, 2:26 PM EDTFlash Flood Warning Considerable damage threatLWXCarroll, Frederick6 hr
Sep 1, 2:26 PM EDTTornado WarningLWXBaltimore, Harford14 min
Sep 1, 2:27 PM EDTTornado Warning Tornado observedLWXAnne Arundel15 min
Sep 1, 2:48 PM EDTTornado Warning Tornado observedLWXBaltimore, Harford27 min
Sep 1, 3:10 PM EDTTornado WarningLWXBaltimore16 min
Sep 1, 3:17 PM EDTTornado WarningLWXHarford28 min
Sep 1, 3:25 PM EDTFlash Flood Warning Considerable damage threatLWXCarroll, Frederick5 hr
Sep 1, 3:34 PM EDTFlash Flood Warning Considerable damage threatLWXCecil, Harford3 hr
Sep 1, 3:49 PM EDTTornado WarningLWXCecil, Harford26 min
Sep 1, 4:13 PM EDTRiver Flood WatchLWXCecil7 hr
Sep 1, 4:13 PM EDTRiver Flood WarningLWXAllegany7 hr
Sep 1, 4:14 PM EDTRiver Flood WarningLWXAllegany9 hr
Sep 1, 4:37 PM EDTAreal Flood WarningLWXBaltimore, Carroll, Harford13 hr
Sep 1, 5:46 PM EDTTornado WarningLWXCecil29 min
Sep 1, 6:08 PM EDTAreal Flood WarningLWXCecil, Harford17 hr
Sep 1, 6:12 PM EDTTornado WarningLWXCecil19 min
Sep 1, 7:03 PM EDTCoastal Flood WarningLWXAnne Arundel8 hr
Sep 1, 7:27 PM EDTAreal Flood WarningLWXAllegany, Washington15 hr
Sep 1, 7:59 PM EDTAreal Flood WarningLWXCarroll, Frederick2 hr

Nearby

Flash Flood Warnings in West Virginia, 2021Flash Flood Warnings in Maryland, 2021Every flash flood warning in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.