Alert archive / Maryland / River Flood Warnings in 2021

River Flood Warning 22, NWS Baltimore/Washington

September 23, 2021Frederick County, Maryland

NWS Baltimore/Washington issued this river flood warning at Sep 23, 2021, 1:18 PM EDT for Frederick County, Maryland. It took effect at Sep 23, 2021, 3:03 PM EDT. It was in force for 23 hr.

The area

The outline as issued.

The facts

Issued: Sep 23, 2021, 1:18 PM EDT (17:18 UTC)
In effect from: Sep 23, 2021, 3:03 PM EDT
Expired: Sep 24, 2021, 2:08 PM EDT
In force: 23 hr
Issued by: NWS Baltimore/Washington
Area: Storm-based polygon
Flood severity: Minor

County Frederick County, MD

The radar

The Sterling radar (KLWX), 50 km from the middle of the area, began a volume at 17:20 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 Monocacy River near Frederick at Interstate 70 (FDKM2). The gauge peaked at 19.03 ft at Sep 24, 2021, 6:00 AM EDT.

Action stage: 13 ft
Minor stage: 15 ft
Moderate stage: 17 ft
Major stage: 20 ft

This gauge today: stage, forecast and historic crests

Stage from the USGS instantaneous record for site 01643000, one reading an hour, from a day before the product to a day after it ended. Flood stages are today's.

The text

As transmitted.

908 
WGUS41 KLWX 231718
FLWLWX

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Flood Warning
National Weather Service Baltimore MD/Washington DC
118 PM EDT Thu Sep 23 2021

...The National Weather Service in Baltimore MD/Washington DC has 
issued a Flood Warning for the following rivers in Maryland...

  Monocacy River near Frederick affecting Frederick County.

For the Monocacy River...including Frederick...Minor flooding is 
forecast.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Stay tuned to further developments by listening to your local radio, 
television, or NOAA Weather Radio for further information.

Additional information is available at www.weather.gov/washington or 
www.weather.gov/baltimore.

The next statement will be issued late tonight at 130 AM EDT.

&&


MDC021-240530-
/O.NEW.KLWX.FL.W.0022.210923T2000Z-210924T0825Z/
/FDKM2.1.ER.210923T2000Z.210924T0000Z.210924T0224Z.NO/
118 PM EDT Thu Sep 23 2021

The National Weather Service in Sterling Virginia has issued a

* Flood Warning for
  the Monocacy River near Frederick.
* Until late tonight.
* At 1:01 PM EDT Thursday the stage was 14.7 feet, or 0.3 feet below 
  flood stage.
* Flood stage is 15.0 feet.
* Minor flooding is forecast.
* Forecast...The river is expected to rise above flood stage late 
  this afternoon to a crest of 15.4 feet this evening. It will then 
  fall below flood stage late this evening.
* Impact...At 15.0 feet, Both banks of the river are flooded. Water 
  begins to flood low-lying fields at Monocacy National Battlefield. 
  Water reaches the access road of the Frederick city wastewater 
  treatment plant. Backwater flooding is occurring on several area 
  creeks, particularly Carroll Creek in Frederick.
* Flood History...This crest compares to a previous crest of 15.3 
  feet on 06/28/2006.

&&

River Name  Fld      Observed    Thu   Fri   Fri     Crest       
Location    Stg   Stg  Day/Time  8PM   2AM   8AM   Stg Time Date 

Monocacy River
Frederick   15.0  14.7 Thu 1 pm  15.4  14.4  13.3  15.4 8pm Thu  


&&

LAT...LON 3958 7738 3955 7731 3940 7735 3924 7741
      3922 7745 3926 7748 3951 7742

$$

BJL

7 follow-up statements

786 
WGUS81 KLWX 231903
FLSLWX

Flood Statement
National Weather Service Baltimore MD/Washington DC
303 PM EDT Thu Sep 23 2021

...The Flood Warning is extended for the following rivers in 
Maryland...

  Monocacy River near Frederick affecting Frederick County.

...The Flood Warning continues for the following rivers in West 
Virginia...

  Opequon Creek near Martinsburg affecting Jefferson and Berkeley 
  Counties.

For the Opequon Creek...including Martinsburg...Minor flooding is 
forecast.
For the Monocacy River...including Frederick...Minor flooding is 
forecast.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Motorists should not attempt to drive around barricades or drive 
cars through flooded areas.

Stay tuned to further developments by listening to your local radio, 
television, or NOAA Weather Radio for further information.

Additional information is available at www.weather.gov/washington or 
www.weather.gov/baltimore.

The next statement will be issued late tonight at 315 AM EDT.

&&


MDC021-240715-
/O.EXT.KLWX.FL.W.0022.210923T1903Z-210924T1600Z/
/FDKM2.1.ER.210923T1727Z.210924T0000Z.210924T1000Z.NO/
303 PM EDT Thu Sep 23 2021

...The Flood Warning is now in effect until early tomorrow 
afternoon...

The Flood Warning continues for
  the Monocacy River near Frederick.
* From this afternoon to early tomorrow afternoon.
* At 2:46 PM EDT Thursday the stage was 15.8 feet, or 0.8 feet above 
  flood stage.
* Flood stage is 15.0 feet.
* Minor flooding is occurring and minor flooding is forecast.
* Recent Activity...The maximum river stage in the 24 hours ending 
  at 2:46 PM EDT Thursday was 15.8 feet.
* Forecast...The river is expected to rise to a crest of 16.9 feet 
  this evening. It will then fall below flood stage tomorrow morning.
* Impact...At 17.0 feet, Significant lowland flooding is occurring 
  along the river, with backwater flooding also occurring. Numerous 
  roads are closed. Water is approaching the parking lot at Gambrill 
  Mill on the Monocacy National Battlefield. Backwater flooding from 
  Carroll Creek is likely approaching the underside of the bridge 
  leading to the Frederick city wastewater treatment plant.
* Flood History...This crest compares to a previous crest of 16.9 
  feet on 03/11/2011.

&&

River Name  Fld      Observed    Thu   Fri   Fri     Crest       
Location    Stg   Stg  Day/Time  8PM   2AM   8AM   Stg Time Date 

Monocacy River
Frederick   15.0  15.8 Thu 2 pm  16.9  16.4  14.5  16.9 8pm Thu  


&&

LAT...LON 3958 7738 3955 7731 3940 7735 3924 7741
      3922 7745 3926 7748 3951 7742

$$

WVC003-037-240715-
/O.EXT.KLWX.FL.W.0021.210923T2022Z-210924T0945Z/
/MBGW2.1.ER.210923T2022Z.210924T0000Z.210924T0345Z.NO/
303 PM EDT Thu Sep 23 2021

...The Flood Warning is now in effect until late tonight...

The Flood Warning continues for
  the Opequon Creek near Martinsburg.
* Until late tonight.
* At 1:30 PM EDT Thursday the stage was 9.2 feet, or 0.8 feet below 
  flood stage.
* Flood stage is 10.0 feet.
* Minor flooding is forecast.
* Forecast...The river is expected to rise above flood stage late 
  this afternoon to a crest of 11.0 feet this evening. It will then 
  fall below flood stage late this evening.
* Impact...At 11.0 feet, Water begins to cover backyards of homes on 
  Bowers Road (County Road 1/1). Douglas Grove Road (County Road 
  9/16) is flooded and impassible. Water also approaches Golf Course 
  Road (County Road 36) and Grapevine Road (County Road 9/14).
* Flood History...This crest compares to a previous crest of 11.0 
  feet on 12/27/1973.

&&

River Name   Fld      Observed    Thu   Fri   Fri     Crest       
Location     Stg   Stg  Day/Time  8PM   2AM   8AM   Stg Time Date 

Opequon Creek
Martinsburg  10.0  9.2  Thu 1 pm  11.0  9.4   7.0   11.0 8pm Thu  


&&

LAT...LON 3929 7807 3932 7804 3943 7799 3955 7792
      3951 7786 3938 7792 3924 7800

$$

BJL

365 
WGUS41 KLWX 232206
FLWLWX

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Flood Warning
National Weather Service Baltimore MD/Washington DC
606 PM EDT Thu Sep 23 2021

...Forecast flooding changed from Minor to Moderate severity for the 
following rivers in Maryland...

  Monocacy River near Frederick affecting Frederick County.

For the Monocacy River...including Frederick...Moderate flooding is 
forecast.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Stay tuned to further developments by listening to your local radio, 
television, or NOAA Weather Radio for further information.

Additional information is available at www.weather.gov/washington or 
www.weather.gov/baltimore.

The next statement will be issued Friday morning at 615 AM EDT.

&&


MDC021-241015-
/O.CON.KLWX.FL.W.0022.000000T0000Z-210924T1600Z/
/FDKM2.2.ER.210923T1727Z.210924T0200Z.210924T1000Z.NO/
606 PM EDT Thu Sep 23 2021

...Forecast flooding increased from Minor to Moderate severity...

The Flood Warning continues for
  the Monocacy River near Frederick.
* Until early tomorrow afternoon.
* At 5:45 PM EDT Thursday the stage was 16.9 feet, or 1.9 feet above 
  flood stage.
* Flood stage is 15.0 feet.
* Minor flooding is occurring and moderate flooding is forecast.
* Recent Activity...The maximum river stage in the 24 hours ending 
  at 5:45 PM EDT Thursday was 16.9 feet.
* Forecast...The river is expected to rise to a crest of 17.2 feet 
  late this evening. It will then fall below flood stage tomorrow 
  morning.
* Impact...At 17.0 feet, Significant lowland flooding is occurring 
  along the river, with backwater flooding also occurring. Numerous 
  roads are closed. Water is approaching the parking lot at Gambrill 
  Mill on the Monocacy National Battlefield. Backwater flooding from 
  Carroll Creek is likely approaching the underside of the bridge 
  leading to the Frederick city wastewater treatment plant.
* Flood History...This crest compares to a previous crest of 17.2 
  feet on 12/02/1934.

&&

River Name  Fld      Observed    Fri   Fri   Fri     Crest       
Location    Stg   Stg  Day/Time  2AM   8AM   2PM   Stg Time Date 

Monocacy River
Frederick   15.0  16.9 Thu 5 pm  16.8  14.5  11.9  17.2 10pm Thu 


&&

LAT...LON 3958 7738 3955 7731 3940 7735 3924 7741
      3922 7745 3926 7748 3951 7742

$$

KJP

524 
WGUS81 KLWX 240146
FLSLWX

Flood Statement
National Weather Service Baltimore MD/Washington DC
946 PM EDT Thu Sep 23 2021

...Observed flooding changed from Minor to Moderate severity and 
increased in duration for the following rivers in Maryland...

  Monocacy River near Frederick affecting Frederick County.

For the Monocacy River...including Frederick...Moderate flooding is 
forecast.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Motorists should not attempt to drive around barricades or drive 
cars through flooded areas.

Stay tuned to further developments by listening to your local radio, 
television, or NOAA Weather Radio for further information.

Additional information is available at www.weather.gov/washington or 
www.weather.gov/baltimore.

The next statement will be issued Friday morning at 945 AM EDT.

&&


MDC021-241400-
/O.EXT.KLWX.FL.W.0022.000000T0000Z-210924T1500Z/
/FDKM2.2.ER.210923T1727Z.210924T0116Z.210924T0900Z.NO/
946 PM EDT Thu Sep 23 2021

...Observed flooding increased from Minor to Moderate severity and 
increased in duration until late tomorrow morning...

The Flood Warning continues for
  the Monocacy River near Frederick.
* Until late tomorrow morning.
* At 9:16 PM EDT Thursday the stage was 17.6 feet, or 2.6 feet above 
  flood stage.
* Flood stage is 15.0 feet.
* Moderate flooding is occurring and minor flooding is forecast.
* Recent Activity...The maximum river stage in the 24 hours ending 
  at 9:16 PM EDT Thursday was 17.6 feet.
* Forecast...The river is expected to fall below flood stage late 
  tonight and continue falling to 5.0 feet Sunday evening.
* Impact...At 17.0 feet, Significant lowland flooding is occurring 
  along the river, with backwater flooding also occurring. Numerous 
  roads are closed. Water is approaching the parking lot at Gambrill 
  Mill on the Monocacy National Battlefield. Backwater flooding from 
  Carroll Creek is likely approaching the underside of the bridge 
  leading to the Frederick city wastewater treatment plant.
* Flood History...This crest compares to a previous crest of 17.5 
  feet on 04/21/1940.

&&

River Name  Fld      Observed    Fri   Fri   Fri     Crest       
Location    Stg   Stg  Day/Time  2AM   8AM   2PM   Stg Time Date 

Monocacy River
Frederick   15.0  17.6 Thu 9 pm  16.5  14.1  11.9  17.8 Thu 10 pm 


&&

LAT...LON 3958 7738 3955 7731 3940 7735 3924 7741
      3922 7745 3926 7748 3951 7742

$$

KJP

980 
WGUS81 KLWX 240550
FLSLWX

Flood Statement
National Weather Service Baltimore MD/Washington DC
150 AM EDT Fri Sep 24 2021

...Forecast flooding changed from Minor to Moderate severity and 
increased in duration for the following rivers in Maryland...

  Monocacy River near Frederick affecting Frederick County.

For the Monocacy River...including Frederick...Moderate flooding is 
forecast.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Motorists should not attempt to drive around barricades or drive 
cars through flooded areas.

Stay tuned to further developments by listening to your local radio, 
television, or NOAA Weather Radio for further information.

Additional information is available at www.weather.gov/washington or 
www.weather.gov/baltimore.

The next statement will be issued this afternoon at 200 PM EDT.

&&


MDC021-241800-
/O.EXT.KLWX.FL.W.0022.000000T0000Z-210924T2100Z/
/FDKM2.2.ER.210923T1727Z.210924T0900Z.210924T1500Z.NO/
150 AM EDT Fri Sep 24 2021

...Forecast flooding increased from Minor to Moderate severity and 
increased in duration until late this afternoon...

The Flood Warning continues for
  the Monocacy River near Frederick.
* Until late this afternoon.
* At 1:30 AM EDT Friday the stage was 18.5 feet, or 3.5 feet above 
  flood stage.
* Flood stage is 15.0 feet.
* Moderate flooding is occurring and moderate flooding is forecast.
* Recent Activity...The maximum river stage in the 24 hours ending 
  at 1:30 AM EDT Friday was 18.5 feet.
* Forecast...The river is expected to rise to a crest of 18.6 feet 
  early this morning. It will then fall below flood stage late this 
  morning.
* Impact...At 17.0 feet, significant lowland flooding is occurring 
  along the river, with backwater flooding also occurring. Numerous 
  roads are closed. Water is approaching the parking lot at Gambrill 
  Mill on the Monocacy National Battlefield. Backwater flooding from 
  Carroll Creek is likely approaching the underside of the bridge 
  leading to the Frederick city wastewater treatment plant.
* Flood History...This crest compares to a previous crest of 18.5 
  feet on 05/19/1988.

&&

River Name  Fld      Observed    Fri   Fri   Fri     Crest       
Location    Stg   Stg  Day/Time  8AM   2PM   8PM   Stg Time Date 

Monocacy River
Frederick   15.0  18.5 Fri 1 am  18.2  12.1  10.1  18.6 5am Fri  


&&

LAT...LON 3958 7738 3955 7731 3940 7735 3924 7741
      3922 7745 3926 7748 3951 7742

$$

BKF

755 
WGUS81 KLWX 241338
FLSLWX

Flood Statement
National Weather Service Baltimore MD/Washington DC
938 AM EDT Fri Sep 24 2021

...The Flood Warning is extended for the following rivers in 
Maryland...

  Monocacy River near Frederick affecting Frederick County.

For the Monocacy River...including Frederick...Moderate flooding is 
occurring.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Motorists should not attempt to drive around barricades or drive 
cars through flooded areas.

Stay tuned to further developments by listening to your local radio, 
television, or NOAA Weather Radio for further information.

Additional information is available at www.weather.gov/washington or 
www.weather.gov/baltimore.

The next statement will be issued this evening at 900 PM EDT.

&&


MDC021-250100-
/O.EXT.KLWX.FL.W.0022.000000T0000Z-210925T0100Z/
/FDKM2.2.ER.210923T1727Z.210924T0946Z.210924T1900Z.NO/
938 AM EDT Fri Sep 24 2021

...The Flood Warning is now in effect until late this evening...

The Flood Warning continues for
  the Monocacy River near Frederick.
* Until late this evening.
* At 9:15 AM EDT Friday the stage was 18.4 feet, or 3.4 feet above 
  flood stage.
* Flood stage is 15.0 feet.
* Moderate flooding is occurring.
* Recent Activity...The maximum river stage in the 24 hours ending 
  at 9:15 AM EDT Friday was 19.0 feet.
* Forecast...The river is expected to fall below flood stage late 
  this afternoon and continue falling to 5.0 feet Monday morning.
* Flood History...This crest compares to a previous crest of 18.4 
  feet on 04/27/1952.

&&

River Name  Fld      Observed    Fri   Fri   Sat     Crest       
Location    Stg   Stg  Day/Time  2PM   8PM   2AM   Stg Time Date 

Monocacy River
Frederick   15.0  18.4 Fri 9 am  15.7  13.2  10.4 19.0 5:45AM 9/24   


&&

LAT...LON 3958 7738 3955 7731 3940 7735 3924 7741
      3922 7745 3926 7748 3951 7742

$$

DHOF

935 
WGUS81 KLWX 241611
FLSLWX

Flood Statement
National Weather Service Baltimore MD/Washington DC
1211 PM EDT Fri Sep 24 2021

...The Flood Warning continues for the following rivers in 
Maryland...

  Monocacy River near Frederick affecting Frederick County.

For the Monocacy River...including Frederick...Minor flooding is 
occurring.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Motorists should not attempt to drive around barricades or drive 
cars through flooded areas.

Stay tuned to further developments by listening to your local radio, 
television, or NOAA Weather Radio for further information.

Additional information is available at www.weather.gov/washington or 
www.weather.gov/baltimore.

The next statement will be issued this evening at 900 PM EDT.

&&


MDC021-250100-
/O.CON.KLWX.FL.W.0022.000000T0000Z-210925T0100Z/
/FDKM2.2.ER.210923T1727Z.210924T0946Z.210924T1900Z.NO/
1211 PM EDT Fri Sep 24 2021

...The Flood Warning remains in effect...

The Flood Warning continues for
  the Monocacy River near Frederick.
* Until late this evening.
* At 12:00 PM EDT Friday the stage was 16.9 feet, or 1.9 feet above 
  flood stage, and falling.
* Flood stage is 15.0 feet.
* Minor flooding is occurring.
* Recent Activity...The maximum river stage in the 24 hours ending 
  at 12:00 PM EDT Friday was 19.0 feet.
* Forecast...The river is expected to fall below flood stage late 
  this afternoon and continue falling to 5.0 feet Monday morning.
* Impact...At 17.0 feet, Significant lowland flooding is occurring 
  along the river, with backwater flooding also occurring. Numerous 
  roads are closed. Water is approaching the parking lot at Gambrill 
  Mill on the Monocacy National Battlefield. Backwater flooding from 
  Carroll Creek is likely approaching the underside of the bridge 
  leading to the Frederick city wastewater treatment plant.
* Flood History...This crest compares to a previous crest of 16.9 
  feet on 03/11/2011.

&&

River Name  Fld      Observed    Fri   Sat   Sat     Crest       
Location    Stg   Stg  Day/Time  8PM   2AM   8AM   Stg Time Date 

Monocacy River
Frederick   15.0  16.9 Fri 12 pm 13.2  10.4  8.8 19.0 5:45AM 9/24 


&&

LAT...LON 3958 7738 3955 7731 3940 7735 3924 7741
      3922 7745 3926 7748 3951 7742

$$

DHOF

514 
WGUS81 KLWX 241808
FLSLWX

Flood Statement
National Weather Service Baltimore MD/Washington DC
208 PM EDT Fri Sep 24 2021

...The Flood Warning is cancelled for the following rivers in 
Maryland...

  Monocacy River near Frederick affecting Frederick County.

MDC021-241915-
/O.CAN.KLWX.FL.W.0022.000000T0000Z-210924T1808Z/
/FDKM2.2.ER.210923T1727Z.210924T0946Z.210924T1900Z.NO/
208 PM EDT Fri Sep 24 2021

...The Flood Warning for the Monocacy River near Frederick has been 
cancelled...

The Flood Warning is cancelled for
  the Monocacy River near Frederick.
* At 1:00 PM EDT Friday the stage was just under 15.0 feet.
* Flood stage is 15.0 feet.
* Recent Activity...The maximum river stage in the 24 hours ending 
  at 1:00 PM EDT Friday was 19.0 feet.
* Forecast...The river is expected to continue falling to 5.0 feet 
  by Monday morning.

&&

River Name  Fld      Observed    Fri   Sat   Sat     Crest       
Location    Stg   Stg  Day/Time  8PM   2AM   8AM   Stg Time Date 

Monocacy River
Frederick   15.0  14.9 Fri 1 pm  13.2  10.4  8.8 19.0 5:45AM 9/24 


&&

LAT...LON 3958 7738 3955 7731 3940 7735 3924 7741
      3922 7745 3926 7748 3951 7742

$$

DHOF

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 Sep 23, 9:44 AM EDT, 3 hours 34 minutes earlier.

Area forecast discussion, Sep 23, 9:44 AM EDT, 3 hours 34 minutes before

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
944 AM EDT Thu Sep 23 2021

.SYNOPSIS...
A strong cold front associated with an area of low pressure
over the Great Lakes will continue to push through the region
this morning through this afternoon, resulting in periods of
heavy rainfall, gusty showers, and embedded thunderstorms.
Meanwhile, high pressure will continue to build into the region
as dry weather returns Friday into the weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
Large upper level low continues to retrograde over the Great
Lakes as an associated cold front continues to push through the
region this morning. Latest radar imagery shows the last batch
of heavy showers and embedded thunderstorms beginning to exit
off into eastern MD. Latest hi-res guidance in conjunction with
the latest obs shows this final band completely clearing the
region within the next hour or so. Latest satellite imagery
shows rapid clearing behind the front with some upslope clouds
across the Alleghenies as a strong W/NW flow ensues.

Numerous Flood Warnings continue across the CWA currently.
However with drying conditions continuing throughout the
remainder of the day, don't anticipate any additional flooding
issues. Will likely be dropping the Flash Flood Watch for the
Baltimore and DC metro areas in the next few hours once the
heavy rain has completely exited the area.

Cooler and drier conditions are expected today through this
weekend with high temperatures this afternoon in the low 70s for
most with some mid 50s across the higher terrain. Lows tonight
will drop down into the mid 40s for most, slightly warmer across
the metros.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
...PREVIOUS DISCUSSION...
Dry and seasonably cool on Friday with highs in the low to mid 70s
as high pressure builds towards the region. This will continue into
Friday night as well, with temps even a touch cooler than Thursday
night.

Temps start to moderate a bit on Saturday as high pressure sets of
to our southwest. Temperatures won't increase much, with highs
closer to the mid 70s. With winds out of the southwest, temps
overnight will trend upwards as well, increasing a few degrees
compared to previous nights.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
High pressure will dominate over the region early next week with
near or slightly below normal temperatures and dry conditions.
Temperatures will moderate Tuesday as the aforementioned high shifts
offshore and winds turning a touch more southerly. Tuesday will also
feature our next chance of precipitation as a weak cold front drops
southward toward the region. Latest guidance depicts scant moisture
with this front, so will maintain low end chance POPs in the
forecast for now. Cooler conditions return toward the middle of next
behind the front as Canadian high pressure builds to our north.

&&

.AVIATION /13Z THURSDAY THROUGH MONDAY/...
The last batch of showers and embedded thunderstorms continue to
exit eastward. Latest radar imagery shows some partial clearing
over BWI with the heaviest of the rain just east of MTN.

Elsewhere, conditions are either or quickly becoming VFR as the
winds shift to the N/NW. VFR conditions are expected to
continue through early next week as high pressure remains in
control.

&&

.MARINE...
Gale Warnings continue through the early afternoon for the
lower Tidal Potomac and the Chesapeake Bay. A Small Craft
Advisory remains in effect for the upper and middle Tidal
Potomac. As a strong cold front continues to track eastward,
gusty showers and thunderstorms are likely where the issuance of
SMWs may be required, and even the potential for an isolated
waterspout.

Northerly winds are expected to develop after the front moves
through the region by Thursday afternoon and persist into Friday.
Additional SCA was issued to cover this threat starting late
tonight. SCA gusts possible in S channeling ahead of a front
Sat PM before becoming NW with SCA gusts possible thru Sun.

Borderline SCA conditions possible Sunday under a westerly wind
regime as high pressure builds mainly south of the waters. The
gradient will relax Sunday night into Monday with continued light
westerly breezes.

&&

.TIDES/COASTAL FLOODING...
Tidal anomalies continue to run high thanks to strong onshore winds
ahead of an approaching cold front. As a result, minor to moderate
tidal flooding is occurring or forecast this morning at all tidal
locations. Confidence in additional tidal flooding with subsequent
high tide cycles this afternoon and evening decreases as winds will
turn offshore as the front slowly crosses the area today. Additional
updates to the forecast will certainly be needed later this morning
as the timing of the front and wind shift becomes clearer, allowing
anomalies to back off.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...Flash Flood Watch until 2 PM EDT this afternoon for DCZ001.
     Coastal Flood Warning until noon EDT today for DCZ001.
MD...Flash Flood Watch until 2 PM EDT this afternoon for MDZ005-006-
     008-011-503>508.
     Coastal Flood Advisory until 2 PM EDT this afternoon for
     MDZ011.
     Coastal Flood Warning until noon EDT today for MDZ014.
     Coastal Flood Advisory until 4 PM EDT this afternoon for
     MDZ508.
VA...Flash Flood Watch until 2 PM EDT this afternoon for VAZ053-054-
     506.
     Coastal Flood Advisory until noon EDT today for VAZ054.
WV...None.
MARINE...Small Craft Advisory until 9 PM EDT this evening for ANZ535-
     536.
     Flash Flood Watch until 2 PM EDT this afternoon for ANZ535.
     Small Craft Advisory until 5 AM EDT Friday for ANZ530>533-
     538>542.
     Gale Warning until noon EDT today for ANZ530>534-537>543.
     Small Craft Advisory until 10 AM EDT Friday for ANZ534-537-543.

&&

SYNOPSIS...CJL/SOUZA
NEAR TERM...SOUZA
SHORT TERM...CJL
LONG TERM...BKF
AVIATION...SOUZA
MARINE...BKF/CJL
TIDES/COASTAL FLOODING...STAFF

Hazardous weather outlook, Sep 23, 12:51 PM EDT, 27 minutes before

Hazardous Weather Outlook
National Weather Service Baltimore MD/Washington DC
1251 PM EDT Thu Sep 23 2021

ANZ530>543-DCZ001-MDZ008-011-013-014-016>018-504-506-508-
VAZ052>057-241700-
Chesapeake Bay north of Pooles Island MD-
Chesapeake Bay from Pooles Island to Sandy Point MD-
Chesapeake Bay from Sandy Point to North Beach MD-
Chesapeake Bay from North Beach to Drum Point MD-
Chesapeake Bay from Drum Point MD to Smith Point VA-
Tidal Potomac from Key Bridge to Indian Head MD-
Tidal Potomac from Indian Head to Cobb Island MD-
Tidal Potomac from Cobb Island MD to Smith Point VA-
Patapsco River including Baltimore Harbor-
Chester River to Queenstown MD-Eastern Bay-
Choptank River to Cambridge MD and the Little Choptank River-
Patuxent River to Broomes Island MD-
Tangier Sound and the inland waters surrounding Bloodsworth
Island-District of Columbia-Cecil-Southern Baltimore-
Prince Georges-Anne Arundel-Charles-St. Marys-Calvert-
Central and Southeast Montgomery-Central and Southeast Howard-
Southeast Harford-Prince William/Manassas/Manassas Park-Fairfax-
Arlington/Falls Church/Alexandria-Stafford-Spotsylvania-
King George-
1251 PM EDT Thu Sep 23 2021

This Hazardous Weather Outlook is for the Maryland portion of the
Chesapeake Bay, Tidal Potomac River, and I-95 corridor through
central Maryland, northern Virginia, and District of Columbia.

.DAY ONE...This Afternoon and Tonight

A Coastal Flood Warning is in effect for Anne Arundel County
through this afternoon.

Multiple Flood Warnings remain in effect for portions of the DC
and Baltimore metro areas.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

MDZ003>006-503-505-507-VAZ025>031-036>040-050-051-501-502-505>508-
WVZ050>053-055-241700-
Washington-Frederick MD-Carroll-Northern Baltimore-
Northwest Montgomery-Northwest Howard-Northwest Harford-Augusta-
Rockingham-Shenandoah-Frederick VA-Page-Warren-Clarke-Nelson-
Albemarle-Greene-Madison-Rappahannock-Orange-Culpeper-
Northern Fauquier-Southern Fauquier-Western Loudoun-
Eastern Loudoun-Northern Virginia Blue Ridge-
Central Virginia Blue Ridge-Hampshire-Morgan-Berkeley-Jefferson-
Hardy-
1251 PM EDT Thu Sep 23 2021

This Hazardous Weather Outlook is for portions of eastern West
Virginia, northern and central Virginia, and central and western
Maryland.

.DAY ONE...This Afternoon and Tonight

Flood Warnings remain in effect for portions of north-central
Maryland and the eastern West Virginia panhandle.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

MDZ001-501-502-VAZ503-504-WVZ501>506-241700-
Garrett-Extreme Western Allegany-Central and Eastern Allegany-
Western Highland-Eastern Highland-Western Grant-Eastern Grant-
Western Mineral-Eastern Mineral-Western Pendleton-
Eastern Pendleton-
1251 PM EDT Thu Sep 23 2021

This Hazardous Weather Outlook is for the Allegheny Front
counties in western Maryland, eastern West Virginia, and Highland
County Virginia.

.DAY ONE...This Afternoon and Tonight

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

DHOF

In the hours before

Local storm report, Sep 23, 12:26 PM EDT, 52 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1226 PM EDT THU SEP 23 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1125 AM     FLOOD            1 NNE RICHARDSMERE      39.71N  76.12W
09/23/2021                   CECIL              MD   911 CALL CENTER

            NEW BRIDGE ROAD CLOSED AT HORSESHOE ROAD DUE TO
            OCTORARO CREEK FLOWING ONTO THE INTERSECTION/BRIDGE.

&&

EVENT NUMBER LWX2106025

CPB

Local storm report, Sep 23, 12:30 PM EDT, 48 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1230 PM EDT THU SEP 23 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1229 PM     FLOOD            1 SSW TANTALLON         38.71N  77.02W
09/23/2021                   PRINCE GEORGES     MD   911 CALL CENTER

            OLD FORT ROAD WAS CLOSED AROUND FORT WASHINGTON ROAD
            DUE TO HIGH WATER.

&&

EVENT NUMBER LWX2106026

BJL

Local storm report, Sep 23, 12:32 PM EDT, 46 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1232 PM EDT THU SEP 23 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1229 PM     FLOOD            BLADENSBURG             38.94N  76.93W
09/23/2021                   PRINCE GEORGES     MD   911 CALL CENTER

            A CAR WAS STUCK IN HIGH WATER IN BLADENSBURG.

&&

EVENT NUMBER LWX2106027

BJL

Local storm report, Sep 23, 12:50 PM EDT, 28 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1250 PM EDT THU SEP 23 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0802 AM     FLOOD            BETHESDA                38.99N  77.12W
09/23/2021                   MONTGOMERY         MD   911 CALL CENTER

            SEVERAL ROADS CLOSED DUE TO HIGH WATER IN/NEAR
            BETHESDA.

&&

EVENT NUMBER LWX2106028

CPB

Local storm report, Sep 23, 1:01 PM EDT, 17 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
101 PM EDT THU SEP 23 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1210 PM     FLOOD            GLENCOE                 39.55N  76.64W
09/23/2021                   BALTIMORE          MD   MESONET

            THE STREAM GAUGE ON GUNPOWDER FALLS AT GLENCOE REACHED
            FLOOD STAGE.

&&

EVENT NUMBER LWX2106029

DH

Local storm report, Sep 23, 1:05 PM EDT, 13 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
105 PM EDT THU SEP 23 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0900 AM     FLOOD            BALTIMORE               39.30N  76.61W
09/23/2021                   BALTIMORE CITY     MD   911 CALL CENTER

            ABOUT A HALF A DOZEN ROADS WERE BLOCKED BY HIGH WATER.

&&

EVENT NUMBER LWX2106030

DH

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 23, 12:25 AM EDT	Coastal Flood Advisory	LWX	Charles	8 hr
Sep 23, 2:02 AM EDT	Areal Flood Warning	LWX	Frederick, Washington	10 hr
Sep 23, 2:34 AM EDT	Flash Flood Warning Considerable damage threat	LWX	Frederick, Washington	3 hr
Sep 23, 3:47 AM EDT	Areal Flood Warning	LWX	Montgomery	12 hr
Sep 23, 3:53 AM EDT	Areal Flood Warning	LWX	Carroll, Frederick	17 hr
Sep 23, 4:17 AM EDT	Flash Flood Warning Considerable damage threat	LWX	Frederick	3 hr
Sep 23, 4:41 AM EDT	Areal Flood Warning	LWX	Howard, Montgomery	9 hr
Sep 23, 5:35 AM EDT	Areal Flood Warning	LWX	Carroll, Frederick	6 hr
Sep 23, 7:08 AM EDT	River Flood Warning	LWX	Montgomery	16 hr
Sep 23, 7:56 AM EDT	Severe Thunderstorm Warning	LWX	Baltimore, Harford	22 min
Sep 23, 8:04 AM EDT	Areal Flood Warning	LWX	Anne Arundel, Baltimore, Harford, Howard, Montgomery, Prince George's and 1 more	10 hr
Sep 23, 9:02 AM EDT	Areal Flood Warning	LWX	Cecil	9 hr
Sep 23, 9:27 AM EDT	Severe Thunderstorm Warning	LWX	Cecil, Harford	78 min
Sep 23, 12:11 PM EDT	Areal Flood Warning	LWX	Frederick	5 hr
Sep 23, 2:15 PM EDT	Coastal Flood Advisory	LWX	Charles	6 hr

Nearby

River Flood Warnings in Maryland, 2021 Every river 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; radar from the NEXRAD Level II archive; the gauge from the NWS water service and the USGS.