Alert archive / Maryland / River Flood Warnings in 2021
River Flood Warning 12, NWS Baltimore/Washington
NWS Baltimore/Washington issued this river flood warning at Aug 31, 2021, 9:36 PM EDT for Washington County, Maryland. It took effect at Sep 1, 2021, 9:00 PM EDT. It was in force for 45 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 31, 2021, 9:36 PM EDT (01:36 UTC)
- In effect from
- Sep 1, 2021, 9:00 PM EDT
- Expired
- Sep 3, 2021, 5:30 PM EDT
- In force
- 45 hr
- Issued by
- NWS Baltimore/Washington
- Area
- Storm-based polygon
- Flood severity
- Major
County Washington County, MD
The radar
The Sterling radar (KLWX), 82 km from the middle of the area, began a volume at 01:39 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 Conococheague Creek at Fairview (FAVM2). The gauge peaked at 10.61 ft at Sep 2, 2021, 7:00 AM EDT.
- Action stage
- 8 ft
- Minor stage
- 10 ft
- Moderate stage
- 12 ft
- Major stage
- 15 ft
This gauge today: stage, forecast and historic crests
Stage from the USGS instantaneous record for site 01614500, 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.
224
WGUS41 KLWX 010136
FLWLWX
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Flood Warning
National Weather Service Baltimore MD/Washington DC
936 PM EDT Tue Aug 31 2021
...The National Weather Service in Baltimore MD/Washington DC has
issued a Flood Warning for the following rivers in Maryland...
Conococheague Creek at Fairview affecting Washington County.
For the Conococheague Creek...including Fairview...Major 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 Wednesday morning at 945 AM EDT.
&&
MDC043-011345-
/O.NEW.KLWX.FL.W.0012.210902T0100Z-210903T2130Z/
/FAVM2.3.ER.210902T0100Z.210902T1800Z.210903T1530Z.NO/
936 PM EDT Tue Aug 31 2021
The National Weather Service in Sterling Virginia has issued a
* Flood Warning for
the Conococheague Creek at Fairview.
* From Wednesday evening to Friday afternoon.
* At 8:45 PM EDT Tuesday the stage was 1.9 feet, or 8.2 feet below
flood stage.
* Flood stage is 10.0 feet.
* Major flooding is forecast.
* Forecast...The river is expected to rise above flood stage late
tomorrow evening to a crest of 15.4 feet early Thursday afternoon.
It will then fall below flood stage late Friday morning.
* Impact...At 15.0 feet, Water floods several homes north of
Williamsport.
* Flood History...This crest compares to a previous crest of 15.2
feet on 06/19/1996.
&&
River Name Fld Observed Wed Wed Wed Crest
Location Stg Stg Day/Time 3AM 9AM 3PM Stg Time Date
Conococheague Creek
Fairview 10.0 1.9 Tue 8 pm MSG MSG MSG 15.4 2pm Thu
&&
LAT...LON 3972 7786 3972 7776 3966 7778 3958 7781
3961 7784 3963 7786 3965 7787
$$
LFR8 follow-up statements
126
WGUS81 KLWX 011328
FLSLWX
Flood Statement
National Weather Service Baltimore MD/Washington DC
928 AM EDT Wed Sep 1 2021
...The Flood Warning continues for the following rivers in
Maryland...
Conococheague Creek at Fairview affecting Washington County.
For the Conococheague Creek...including Fairview...Major flooding is
forecast.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Stay tuned to further developments by listening to your local radio,
television, or NOAA Weather Radio for further information.
Additional information is available at www.weather.gov/washington or
www.weather.gov/baltimore.
The next statement will be issued this evening at 930 PM EDT.
&&
MDC043-020130-
/O.CON.KLWX.FL.W.0012.210902T0100Z-210903T2130Z/
/FAVM2.3.ER.210902T0100Z.210902T1800Z.210903T1530Z.NO/
928 AM EDT Wed Sep 1 2021
...The Flood Warning remains in effect...
The Flood Warning continues for
the Conococheague Creek at Fairview.
* From this evening to Friday afternoon.
* At 8:45 AM EDT Wednesday the stage was 1.9 feet, or 8.1 feet below
flood stage.
* Flood stage is 10.0 feet.
* Major flooding is forecast.
* Forecast...The river is expected to rise above flood stage late
this evening to a crest of 15.4 feet early tomorrow afternoon. It
will then fall below flood stage late Friday morning.
* Impact...At 15.0 feet, water floods several homes north of
Williamsport.
* Flood History...This crest compares to a previous crest of 15.2
feet on 06/19/1996.
&&
River Name Fld Observed Wed Wed Thu Crest
Location Stg Stg Day/Time 2PM 8PM 2AM Stg Time Date
Conococheague Creek
Fairview 10.0 1.9 Wed 8 am 4.4 9.1 11.7 15.4 2pm Thu
&&
LAT...LON 3972 7786 3972 7776 3966 7778 3958 7781
3961 7784 3963 7786 3965 7787
$$
BKF947
WGUS81 KLWX 011538
FLSLWX
Flood Statement
National Weather Service Baltimore MD/Washington DC
1138 AM EDT Wed Sep 1 2021
...The Flood Warning continues for the following rivers in
Maryland...
Conococheague Creek at Fairview affecting Washington County.
For the Conococheague Creek...including Fairview...Major 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 this evening at 1145 PM EDT.
&&
MDC043-020345-
/O.CON.KLWX.FL.W.0012.210902T0100Z-210903T2130Z/
/FAVM2.3.ER.210902T0300Z.210902T1800Z.210903T1400Z.NO/
1138 AM EDT Wed Sep 1 2021
...The Flood Warning remains in effect...
The Flood Warning continues for
the Conococheague Creek at Fairview.
* From this evening to Friday afternoon.
* At 10:45 AM EDT Wednesday the stage was 2.0 feet, or 8.1 feet
below flood stage.
* Flood stage is 10.0 feet.
* Major flooding is forecast.
* Forecast...The river is expected to rise above flood stage late
this evening to a crest of 15.3 feet early tomorrow afternoon. It
will then fall below flood stage late Friday morning.
* Impact...At 15.0 feet, Water floods several homes north of
Williamsport.
* Flood History...This crest compares to a previous crest of 15.2
feet on 06/19/1996.
&&
River Name Fld Observed Wed Thu Thu Crest
Location Stg Stg Day/Time 8PM 2AM 8AM Stg Time Date
Conococheague Creek
Fairview 10.0 2.0 Wed 10 am 8.8 11.5 13.8 15.3 2pm Thu
&&
LAT...LON 3972 7786 3972 7776 3966 7778 3958 7781
3961 7784 3963 7786 3965 7787
$$
BKF775
WGUS81 KLWX 012010
FLSLWX
Flood Statement
National Weather Service Baltimore MD/Washington DC
410 PM EDT Wed Sep 1 2021
...The Flood Warning continues for the following rivers in
Maryland...
Conococheague Creek at Fairview affecting Washington County.
For the Conococheague Creek...including Fairview...Moderate flooding
is forecast.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Stay tuned to further developments by listening to your local radio,
television, or NOAA Weather Radio for further information.
Additional information is available at www.weather.gov/washington or
www.weather.gov/baltimore.
The next statement will be issued late tonight at 415 AM EDT.
&&
MDC043-020815-
/O.EXT.KLWX.FL.W.0012.210902T0300Z-210903T1700Z/
/FAVM2.2.ER.210902T0300Z.210902T1800Z.210903T1100Z.NO/
410 PM EDT Wed Sep 1 2021
...The Flood Warning is now in effect until early Friday afternoon...
The Flood Warning continues for
the Conococheague Creek at Fairview.
* From this evening to early Friday afternoon.
* At 2:45 PM EDT Wednesday the stage was 3.4 feet, or 6.6 feet below
flood stage.
* Flood stage is 10.0 feet.
* Moderate flooding is forecast.
* Forecast...The river is expected to rise above flood stage late
this evening to a crest of 13.7 feet early tomorrow afternoon. It
will then fall below flood stage Friday morning.
* Impact...At 13.0 feet, Water reaches backyards of homes near
Wilson's Bridge. Numerous roads are flooded.
* Flood History...This crest compares to a previous crest of 13.8
feet on 09/19/2004.
&&
River Name Fld Observed Wed Thu Thu Crest
Location Stg Stg Day/Time 8PM 2AM 8AM Stg Time Date
Conococheague Creek
Fairview 10.0 3.4 Wed 2 pm 7.6 11.8 13.2 13.7 2pm Thu
&&
LAT...LON 3972 7786 3972 7776 3966 7778 3958 7781
3961 7784 3963 7786 3965 7787
$$
LFR636
WGUS81 KLWX 020254
FLSLWX
Flood Statement
National Weather Service Baltimore MD/Washington DC
1054 PM EDT Wed Sep 1 2021
...The Flood Warning continues for the following rivers in
Maryland...
Conococheague Creek at Fairview affecting Washington County.
For the Conococheague Creek...including Fairview...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 Thursday morning at 1100 AM EDT.
&&
MDC043-021500-
/O.EXT.KLWX.FL.W.0012.210902T0419Z-210903T0500Z/
/FAVM2.1.ER.210902T0419Z.210902T1200Z.210902T2300Z.NO/
1054 PM EDT Wed Sep 1 2021
...The Flood Warning is now in effect until early Friday morning...
The Flood Warning continues for
the Conococheague Creek at Fairview.
* Until early Friday morning.
* At 9:45 PM EDT Wednesday the stage was 9.1 feet, or 0.9 feet below
flood stage.
* Flood stage is 10.0 feet.
* Minor flooding is forecast.
* Forecast...The river is expected to rise above flood stage just
after midnight tonight to a crest of 11.4 feet tomorrow morning.
It will then fall below flood stage tomorrow evening.
* Impact...At 11.0 feet, Several roads, including Wishard Road,
Kemps Mill Road, Independence Road, Cress Pond Road, and Walnut
Point Road, are flooded north of Williamsport.
* Flood History...This crest compares to a previous crest of 11.4
feet on 02/26/1961.
&&
River Name Fld Observed Thu Thu Thu Crest
Location Stg Stg Day/Time 2AM 8AM 2PM Stg Time Date
Conococheague Creek
Fairview 10.0 9.1 Wed 9 pm 10.6 11.4 11.2 11.4 8am Thu
&&
LAT...LON 3972 7786 3972 7776 3966 7778 3958 7781
3961 7784 3963 7786 3965 7787
$$
JMG622
WGUS81 KLWX 020859
FLSLWX
Flood Statement
National Weather Service Baltimore MD/Washington DC
459 AM EDT Thu Sep 2 2021
...The Flood Warning continues for the following rivers in
Maryland...
Conococheague Creek at Fairview affecting Washington County.
For the Conococheague Creek...including Fairview...Minor flooding is
forecast.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Stay tuned to further developments by listening to your local radio,
television, or NOAA Weather Radio for further information.
Additional information is available at www.weather.gov/washington or
www.weather.gov/baltimore.
The next statement will be issued this afternoon at 500 PM EDT.
&&
MDC043-022100-
/O.CON.KLWX.FL.W.0012.000000T0000Z-210903T0500Z/
/FAVM2.1.ER.210902T0546Z.210902T1200Z.210902T2300Z.NO/
459 AM EDT Thu Sep 2 2021
...The Flood Warning remains in effect...
The Flood Warning continues for
the Conococheague Creek at Fairview.
* Until just after midnight tonight.
* At 3:45 AM EDT Thursday the stage was 10.3 feet, or 0.3 feet above
flood stage.
* Flood stage is 10.0 feet.
* Minor flooding is occurring and minor flooding is forecast.
* Recent Activity...The maximum river stage in the 24 hours ending
at 3:45 AM EDT Thursday was 10.3 feet.
* Forecast...The river is expected to rise to a crest of 11.1 feet
this morning. It will then fall below flood stage this evening.
* Impact...At 11.0 feet, Several roads, including Wishard Road,
Kemps Mill Road, Independence Road, Cress Pond Road, and Walnut
Point Road, are flooded north of Williamsport.
* Flood History...This crest compares to a previous crest of 11.1
feet on 02/24/1998.
&&
River Name Fld Observed Thu Thu Thu Crest
Location Stg Stg Day/Time 8AM 2PM 8PM Stg Time Date
Conococheague Creek
Fairview 10.0 10.3 Thu 3 am 11.1 11.0 9.9 11.1 8am Thu
&&
LAT...LON 3972 7786 3972 7776 3966 7778 3958 7781
3961 7784 3963 7786 3965 7787
$$
JMG856
WGUS81 KLWX 021511
FLSLWX
Flood Statement
National Weather Service Baltimore MD/Washington DC
1111 AM EDT Thu Sep 2 2021
...The Flood Warning continues for the following rivers in
Maryland...
Conococheague Creek at Fairview affecting Washington County.
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 this evening at 600 PM EDT.
&&
MDC043-022200-
/O.EXT.KLWX.FL.W.0012.000000T0000Z-210902T2200Z/
/FAVM2.1.ER.210902T0546Z.210902T1100Z.210902T1703Z.NO/
1111 AM EDT Thu Sep 2 2021
...The Flood Warning is now in effect until this evening...
The Flood Warning continues for
the Conococheague Creek at Fairview.
* Until this evening.
* At 9:45 AM EDT Thursday the stage was 10.4 feet, or 0.3 feet above
flood stage.
* Flood stage is 10.0 feet.
* Minor flooding is occurring.
* Recent Activity...The maximum river stage in the 24 hours ending
at 9:45 AM EDT Thursday was 10.6 feet.
* Forecast...The river is expected to fall below flood stage this
afternoon and continue falling to 3.7 feet Sunday morning.
* Impact...At 10.0 feet, Wishard Road and Kemp Mill Road are both
flooded.
* Flood History...This crest compares to a previous crest of 10.4
feet on 12/30/1942.
&&
River Name Fld Observed Thu Fri Fri Crest
Location Stg Stg Day/Time 8PM 2AM 8AM Stg Time Date
Conococheague Creek
Fairview 10.0 10.4 Thu 9 am 8.8 7.6 6.7 10.6 Thurs 6:15 am
&&
LAT...LON 3972 7786 3972 7776 3966 7778 3958 7781
3961 7784 3963 7786 3965 7787
$$
KJP595
WGUS81 KLWX 021906
FLSLWX
Flood Statement
National Weather Service Baltimore MD/Washington DC
306 PM EDT Thu Sep 2 2021
...The Flood Warning is extended for the following rivers in
Maryland...
Conococheague Creek at Fairview affecting Washington County.
Susquehanna Below Conowingo Dam affecting Cecil and Harford
Counties.
...The Flood Warning continues for the following rivers in
Maryland...West Virginia...
Potomac River at Shepherdstown affecting Jefferson, Washington
and Berkeley Counties.
Monocacy River near Frederick affecting Frederick County.
For the Potomac River...including Paw Paw, Hancock, Dam Number Five,
Shepherdstown, Harpers Ferry, Point of Rocks, Edwards Ferry, Little
Falls...Minor flooding is forecast.
For the Monocacy River...including Frederick...Moderate flooding is
forecast.
For the Susquehanna River...including Conowingo Dam...Minor flooding
is forecast.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Additional information is available at www.weather.gov/washington or
www.weather.gov/baltimore.
The next statement will be issued this evening at 930 PM EDT.
&&
MDC043-030130-
/O.EXT.KLWX.FL.W.0012.000000T0000Z-210903T0120Z/
/FAVM2.1.ER.210902T0546Z.210902T1100Z.210902T1920Z.NO/
306 PM EDT Thu Sep 2 2021
...The Flood Warning is now in effect until late this evening...
The Flood Warning continues for
the Conococheague Creek at Fairview.
* Until late this evening.
* At 2:45 PM EDT Thursday the stage was 10.2 feet, or 0.2 feet above
flood stage.
* Flood stage is 10.0 feet.
* Minor flooding is occurring.
* Recent Activity...The maximum river stage in the 24 hours ending
at 2:45 PM EDT Thursday was 10.3 feet.
* Forecast...The river is expected to fall below flood stage late
this afternoon and continue falling to 3.5 feet early Sunday
afternoon.
* Impact...At 10.0 feet, Wishard Road and Kemp Mill Road are both
flooded.
* Flood History...This crest compares to a previous crest of 10.2
feet on 06/14/1951.
&&
River Name Fld Observed Thu Fri Fri Crest
Location Stg Stg Day/Time 8PM 2AM 8AM Stg Time Date
Conococheague Creek
Fairview 10.0 10.2 Thu 2 pm 8.8 7.6 6.7 MSG unknown
&&
LAT...LON 3972 7786 3972 7776 3966 7778 3958 7781
3961 7784 3963 7786 3965 7787
$$
MDC043-WVC003-037-030715-
/O.EXT.KLWX.FL.W.0016.210903T0100Z-210903T1321Z/
/SHEW2.1.ER.210903T0100Z.210903T0600Z.210903T0721Z.NO/
306 PM EDT Thu Sep 2 2021
...The Flood Warning is now in effect until late tomorrow morning...
The Flood Warning continues for
the Potomac River at Shepherdstown.
* From this evening to late tomorrow morning.
* At 2:46 PM EDT Thursday the stage was 12.5 feet, or 2.5 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 evening to a crest of 15.7 feet just after midnight tonight.
It will then fall below flood stage late tonight.
* Impact...At 16.0 feet, Water goes over the banks of the Potomac
near the mouth of the Opequon River.
* Flood History...This crest compares to a previous crest of 15.7
feet on 02/27/1972.
&&
River Name Fld Observed Thu Fri Fri Crest
Location Stg Stg Day/Time 8PM 2AM 8AM Stg Time Date
Potomac River
Shepherdstown 15.0 12.5 Thu 2 pm 14.7 15.7 12.6 15.7 2am Fri
&&
LAT...LON 3941 7779 3944 7782 3947 7782 3952 7788
3952 7786 3954 7784 3953 7780 3950 7775
3945 7775 3942 7771
$$
MDC015-025-030715-
/O.EXT.KLWX.FL.W.0017.210903T0600Z-000000T0000Z/
/CNWM2.1.ER.210903T0600Z.210903T0600Z.000000T0000Z.NO/
306 PM EDT Thu Sep 2 2021
...The Flood Warning is now in effect until further notice...
The Flood Warning continues for
the Susquehanna Below Conowingo Dam.
* From late tonight until further notice.
* At 2:30 PM EDT Thursday the stage was 22.2 feet, or 1.3 feet below
flood stage.
* Flood stage is 23.5 feet.
* Minor flooding is forecast.
* Forecast...The river is expected to rise above flood stage just
after midnight tonight and continue rising to 23.5 feet just after
midnight tonight. Additional rises are possible thereafter.
* Impact...At 23.7 feet, Minor flooding begins in the town of Port
Deposit, Maryland.
* Flood History...This crest compares to a previous crest of 23.5
feet on 05/18/1989.
&&
River Name Fld Observed Crest
Location Stg Stg Day/Time 6 hr 12hr 18 Stg Time Date
Susquehanna
Conowingo Dam 23.5 22.2 Thu 2 pm MSG MSG MSG MSG unknown
&&
LAT...LON 3966 7622 3968 7616 3955 7604 3952 7611
$$
MDC021-030715-
/O.CON.KLWX.FL.W.0015.000000T0000Z-210903T1300Z/
/FDKM2.3.ER.000000T0000Z.210902T1801Z.210903T0700Z.NO/
306 PM EDT Thu Sep 2 2021
...The Flood Warning remains in effect...
The Flood Warning continues for
the Monocacy River near Frederick.
* Until late tomorrow morning.
* At 2:46 PM EDT Thursday the stage was 22.0 feet, or 7.0 feet above
flood stage.
* Flood stage is 15.0 feet.
* Major flooding is occurring and moderate flooding is forecast.
* Recent Activity...The maximum river stage in the 24 hours ending
at 2:46 PM EDT Thursday was 22.0 feet.
* Forecast...The river is expected to fall below flood stage late
tonight and continue falling to 5.4 feet early Sunday afternoon.
* Impact...At 21.0 feet, Maryland Route 26 is flooded near the
Monocacy River bridge.
* Flood History...This crest compares to a previous crest of 22.0
feet on 09/06/1979.
&&
River Name Fld Observed Thu Fri Fri Crest
Location Stg Stg Day/Time 8PM 2AM 8AM Stg Time Date
Monocacy River
Frederick 15.0 22.0 Thu 2 pm 19.2 15.7 13.2 MSG unknown
&&
LAT...LON 3958 7738 3955 7731 3940 7735 3924 7741
3922 7745 3926 7748 3951 7742
$$
LFR533
WGUS81 KLWX 030127
FLSLWX
Flood Statement
National Weather Service Baltimore MD/Washington DC
927 PM EDT Thu Sep 2 2021
...The Flood Warning is expired for the following rivers in
Maryland...
Conococheague Creek at Fairview affecting Washington County.
MDC043-030230-
/O.EXP.KLWX.FL.W.0012.000000T0000Z-210903T0120Z/
/FAVM2.1.ER.210902T0546Z.210902T1100Z.210902T1920Z.NO/
927 PM EDT Thu Sep 2 2021
...The Flood Warning for the Conococheague Creek at Fairview has
expired...
The Flood Warning has expired for
the Conococheague Creek at Fairview.
* At 8:45 PM EDT Thursday the stage was 9.9 feet, or 0.1 feet below
flood stage.
* Flood stage is 10.0 feet.
* Recent Activity...The maximum river stage in the 24 hours ending
at 2:45 PM EDT Thursday was 10.3 feet.
* Forecast...The river will continue to slowly fall further below
flood stage.
&&
River Name Fld Observed Fri Fri Fri Crest
Location Stg Stg Day/Time 2AM 8AM 2PM Stg Time Date
Conococheague Creek
Fairview 10.0 10.2 Thu 2 pm 7.6 6.7 6.1 MSG unknown
&&
LAT...LON 3972 7786 3972 7776 3966 7778 3958 7781
3961 7784 3963 7786 3965 7787
$$
RCMWhat 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 Aug 31, 9:26 PM EDT, 10 minutes earlier.
Area forecast discussion, Aug 31, 9:26 PM EDT, 10 minutes before
Area Forecast Discussion...UPDATED
National Weather Service Baltimore MD/Washington DC
926 PM EDT Tue Aug 31 2021
.SYNOPSIS...
A front will lift northward overnight as the remnants of Ida
approach from the southwest. The remnants of Ida will interact
with that frontal boundary tomorrow into tomorrow night as it
progresses through our area. Ida's remnants will track off to
our north and east on Thursday, allowing high pressure to build
over the area for Friday through the weekend.
&&
.NEAR TERM /THROUGH TONIGHT/...
Frontal zone has shifted south of the area per sfc obs and model
MSLP fields. A weak wedge of high pressure seems to be in place
west of U.S. 29. Hopefully, this will keep air mass stable
overnight minimizing the tornado risk overnight. However,
showers are expected to increase overnight as overrunning
strengthens. However, areas south of the Rappahannock River may
see the tornado risk increase toward daybreak.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... All eyes will
turn to the remnants of Ida tomorrow, as a potentially
significant weather event unfolds across our area. While there
still is a small amount of spread, 12z guidance has started to
come into better agreement with respect to the track of Ida and
the resultant rainfall distribution across the area.
The character of the event can be split up into two separate
regimes across our forecast area. The first regime will be to
the west of the Blue Ridge, where steady precipitation will
persist nearly continuously from tonight through tomorrow
afternoon. Dynamically speaking, this is where the remnants of
Ida will interact with the mid-latitude trough off to our north
and west, undergoing extratropical transition as it tracks
across our forecast area. As the remnant wind field and copious
amounts of moisture associated with Ida encounter the
baroclinic zone associated with the trough to our west, strong
warm advection/frontogenesis will ensue aloft, leading to a long
lived period of heavy rainfall within the right entrance region
of the upper level jet situated to our north. This prolonged
period of steady, heavy rain will primarily be located across
the WV Panhandle and western MD, where widespread rainfall
totals of 3-6" are expected, with localized totals exceeding 8"
also possible. Some of these totals may also extend across far
northern MD further to the east as the zone of interaction
between Ida and the upper jet spreads eastward across PA. This
will lead to a high end threat for flash flooding across these
areas tomorrow, and then a threat for river flooding in the days
following (see hydrology section for details).
Locations to the east of the Blue Ridge will be further
displaced from the upper trough and resultant jet dynamics. As a
result, many locations there may start off the day dry. Not
only will locations be dry, but a few breaks of filtered
sunshine may develop by later in the morning into the early
afternoon hours. This will lead destabilization, with MLCAPE
values increasing into the 1000-1500 J/kg range. Also of note
from a thermodynamic perspective is the steepening of low-level
lapse rates near the surface in many of the CAMs, which when combined
with 3CAPE values of 100-150 J/kg should promote low-level
stretching of vertical vorticity in any stronger storms.
Kinematically speaking, the wind field associated with the
remnants of Ida is very impressive, with 40-50 knots of flow
extending from 925 hPa all the way up through the mid-levels of
the atmosphere. Hodographs have impressive clockwise curvature
through up 6 km, making ample streamwise vorticity available to
any right moving storms. CAMs show multiple arcs of storms
developing to the east of the Blue Ridge tomorrow afternoon.
Given the environment in place, any storm that forms tomorrow,
whether discrete or embedded within a larger linear structure
should be capable of exhibiting supercellular characteristics.
Multiple tornadoes and instances of damaging straight line winds
appear possible across the area in association with these
storms. As a result, the Storm Prediction Center has upgraded a
large portion of the area to the east of the Blue Ridge to an
Enhanced Risk for severe thunderstorms.
While rainfall won't be steady to the east of the Blue Ridge,
individual thunderstorms will be capable of producing very high
instantaneous rainfall rates, given the potential for very
strong updrafts and the high precipitable water environment in
place. As a result, flash flooding is also possible in these
areas as well, but on a more localized basis compared to west of
the Blue Ridge.
Ida's remnants will progress off to the east overnight Wednesday
night, bringing precipitation to an end areawide by daybreak
Thursday. High pressure will build in behind Ida during the day
Thursday, bringing a return to quieter weather conditions.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
Not much change in the thinking for the medium range period. The
remnants of Ida are expected to be offshore by Friday morning with
high pressure building in from the Great Lakes region. Our area will
still feel the effects from Ida in the form of a northerly flow on
the far western edge of the remnant system. The northerly flow will
lead to cooler and drier conditions, with highs in the mid to upper
70s Friday and highs in the upper 70s to lower 80s on Saturday. Near
to below average overnight lows are forecast both Friday and
Saturday nights in the 50s to lower 60s.
A return flow is forecast to return on Sunday as a cold front
approaches from the northwest. Ahead of the front, southerly flow
will lead to weak warm air advection with afternoon highs trending
up into the mid 80s with dewpoints in the mid 60s. Showers will be
possible late Sunday afternoon and into the evening as the front
combined with shortwave energy aloft provides enough lift for
precipitation to form. The threat for thunderstorms appears minimal
as the shear remains weak and the instability is low. Winds will
become northwesterly behind the frontal passage and cooler and drier
air should limit the threat for any precipitation on Monday.
Overnight lows Sunday into Monday will be mild in the 60s with highs
peaking in the mid 80s
&&
.AVIATION /01Z WEDNESDAY THROUGH SUNDAY/...
These showers and storms will lift northward through the area
overnight. Ceilings will lower as this activity moves through
and remain low end MVFR to high end IFR across the area through
the second half of the night and through the daytime hours
tomorrow. Shower/thunderstorm activity will persist through the
morning to the west of the Blue Ridge, including MRB.
Thunderstorms will develop and spread across the area from west
to east tomorrow afternoon. These storms could be quite intense,
and confidence is high that they will occur, so VCTS has been
added to the TAF sites to the east of the Blue Ridge. Rain will
pull out of the area from west to east during the overnight
hours Wednesday night. Winds may briefly pick up for a short
time late Wednesday night on the back side of Ida. VFR
conditions are expected for both Thursday and Friday as high
pressure builds into the area.
Mainly VFR with NE flow becoming SE this weekend.
&&
.MARINE...
Easterly to southerly flow will strengthen late tonight into
Wednesday as the approaching remnants of Ida cause the front to
strengthen and lift back north. Very strong wind a couple
thousand feet above the surface will likely be mixed down in
stronger showers and thunderstorms Wednesday afternoon into
Wednesday night. Some gusts to well in excess of gale force are
possible, along with waterspouts and greatly reduced
visibility/higher waves with heavy rain bands and thunderstorms.
The remnants of Ida will traverse the waters Wednesday night, moving
east and heading out to sea by Thursday morning. This will turn the
wind to the northeast. Some guidance indicates a period of very
gusty winds as the low departs, so gale conditions are possible
Thursday morning. The wind should gradually subside later Thursday.
&&
.HYDROLOGY...
The remnants of Ida will interact with a stalled frontal
boundary over our region tonight through late Wednesday night.
This will result in a period of very heavy rainfall,
particularly near the MD/PA border and into eastern WV. Average
rainfall amounts are currently expected to be around 3-6 inches
in this area, with locally high end amounts of 8-10 inches
possible. Areas further south and east will be closer to 1-3
inches, with higher localized maxima where training of
thunderstorms occurs. This amount of rainfall would result in
scattered to numerous instances of flooding/flash flooding, some
considerable. Additionally, in the days following, expect river
flooding to become an issue. Many locations are forecast to
enter minor or moderate flood stage, and river flood watches
have been issued accordingly for locations that are expected to
reach flood stage in the next 48 hours. A few locations may
even approach major flooding, especially across northwestern
portions of the forecast area. Additional river flood watches
will likely be issued as confidence increases and the event
draws nearer.
&&
.TIDES/COASTAL FLOODING...
A Coastal Flood Watch has been issued for Annapolis based on
CBOFS and PETSS guidance. Anomalies will rise over the next
couple of days as the remnants of Ida approach from the
southwest. Strengthening S/SE winds will pile up water along the
shore. The range of possibilities remains somewhat large, with
PETSS guidance continuing to show moderate flooding at more
vulnerable locations like Annapolis. Though possible, the
relatively progressive nature of the strongest southerly flow
may tend to keep things below moderate, so have sided more with
the ETSS/ESTOFS for now, but this bears a close watch the next
36 hours before offshore flow takes over and decreases water
levels Thursday into Friday.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...Flash Flood Watch from Wednesday morning through Thursday
morning for DCZ001.
MD...Flash Flood Watch from 2 AM EDT Wednesday through late
Wednesday night for MDZ001-003-501-502.
Flash Flood Watch from Wednesday morning through Thursday
morning for MDZ004>006-008-011-013-014-016>018-503>508.
Coastal Flood Watch from Wednesday evening through Thursday
morning for MDZ014.
VA...Flash Flood Watch from 2 AM EDT Wednesday through late
Wednesday night for VAZ025>031-503-504.
Flash Flood Watch from Wednesday morning through Thursday
morning for VAZ036>040-050>057-501-502-505>508.
WV...Flash Flood Watch from 2 AM EDT Wednesday through late
Wednesday night for WVZ050>053-055-501>506.
MARINE...Flash Flood Watch from Wednesday morning through Thursday
morning for ANZ535.
Small Craft Advisory until noon EDT Wednesday for ANZ530>543.
Gale Warning from noon Wednesday to 6 AM EDT Thursday for
ANZ530>543.
&&
SYNOPSIS...LFR
NEAR TERM...LFR
SHORT TERM...KJP
LONG TERM...DHOF
AVIATION...LFR/DHOF
MARINE...LFR/DHOF
HYDROLOGY...LWX
TIDES/COASTAL FLOODING...LFRHazardous weather outlook, Aug 31, 9:08 PM EDT, 28 minutes before
Hazardous Weather Outlook National Weather Service Baltimore MD/Washington DC 908 PM EDT Tue Aug 31 2021 ANZ530>543-DCZ001-MDZ008-011-013-014-016>018-504-506-508- VAZ052>057-020115- 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- 908 PM EDT Tue Aug 31 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...Tonight A Tornado Watch is in effect for Spotsylvania County until 3 AM tonight. A few severe thunderstorms capable of damaging wind gusts are possible tonight, mainly near and south of the Washington Metropolitan Area. An isolated instance of flooding is also possible. .DAYS TWO THROUGH SEVEN...Wednesday through Monday A Flash Flood Watch is in effect from Wednesday morning through early Thursday morning. Heavy tropical rainfall could result in considerable flash flooding. Flooding on mainstem rivers may then persist through the end of the week. Scattered damaging wind gusts and a few tornadoes are possible with thunderstorms Wednesday afternoon into Wednesday evening. A Gale Warning is in effect Wednesday afternoon and night. A Coastal Flood Watch is in effect for Anne Arundel County from Wednesday evening through Thursday morning. .SPOTTER INFORMATION STATEMENT... Spotter activation will be required tonight. MDZ003>006-503-505-507-VAZ025>031-036>040-050-051-501-502-505>508- WVZ050>053-055-020115- 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- 908 PM EDT Tue Aug 31 2021 This Hazardous Weather Outlook is for portions of eastern West Virginia, northern and central Virginia, and central and western Maryland. .DAY ONE...Tonight A Tornado Watch is in effect for areas generally south of Route 211 until 3 AM tonight. Thunderstorms tonight could produce an isolated damaging wind gust or an isolated instance of flooding, generally near and south of Interstate 66. A Flash Flood Watch is in effect for locations west of the Blue Ridge and Catoctin Mountains late tonight. .DAYS TWO THROUGH SEVEN...Wednesday through Monday A Flash Flood Watch continues for locations west of the Blue Ridge and Catoctin Mountains through late Wednesday night. A Flash Flood Watch is in effect for central Maryland and north- central Virginia from Wednesday morning through early Thursday morning. Heavy tropical rainfall could result in considerable flash flooding. River flooding is also possible, which could continue through the end of the week. Scattered damaging wind gusts and a few tornadoes are possible with thunderstorms Wednesday afternoon into Wednesday evening. A River Flood Watch is in effect for several river basins in parts of western and northern Maryland and the eastern panhandle of West Virginia starting Thursday morning. .SPOTTER INFORMATION STATEMENT... Spotter activation will be required tonight. MDZ001-501-502-VAZ503-504-WVZ501>506-020115- Garrett-Extreme Western Allegany-Central and Eastern Allegany- Western Highland-Eastern Highland-Western Grant-Eastern Grant- Western Mineral-Eastern Mineral-Western Pendleton- Eastern Pendleton- 908 PM EDT Tue Aug 31 2021 This Hazardous Weather Outlook is for the Allegheny Front counties in western Maryland, eastern West Virginia, and Highland County Virginia. .DAY ONE...Tonight Showers and thunderstorms could produce an isolated instance of flooding this afternoon and evening. A Flash Flood Watch is in effect starting late tonight. .DAYS TWO THROUGH SEVEN...Wednesday through Monday A Flash Flood Watch continues through late Wednesday night. Heavy tropical rainfall could result in considerable flash flooding. River flooding is also possible, which could continue into Thursday. A River Flood Watch is in effect for a few river basins in parts of western Maryland and eastern West Virginia starting Thursday morning. .SPOTTER INFORMATION STATEMENT... Spotter activation may be necessary Wednesday.
The office that day
Everything else NWS Baltimore/Washington issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 31, 9:06 PM EDT | Coastal Flood Watch | LWX | Anne Arundel | 22 hr |
| Aug 31, 9:44 PM EDT | River Flood Watch | LWX | Frederick | 25 hr |
| Aug 31, 9:44 PM EDT | River Flood Watch | LWX | Montgomery | 48 hr |
| Aug 31, 9:44 PM EDT | River Flood Watch | LWX | Washington | 25 hr |
| Aug 31, 9:44 PM EDT | River Flood Watch | LWX | Montgomery | 25 hr |
| Sep 1, 3:23 AM EDT | Areal Flood Warning | LWX | Montgomery | 8 hr |
| Sep 1, 3:24 AM EDT | Severe Thunderstorm Warning | LWX | Montgomery, Prince George's | 51 min |
| Sep 1, 3:50 AM EDT | Areal Flood Warning | LWX | Montgomery, Prince George's | 6 hr |
| Sep 1, 4:00 AM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Prince George's | 60 min |
| Sep 1, 4:10 AM EDT | Areal Flood Warning | LWX | Anne Arundel, Baltimore, Howard, City of Baltimore | 6 hr |
| Sep 1, 4:34 AM EDT | Areal Flood Warning | LWX | Montgomery | 6 hr |
| Sep 1, 4:39 AM EDT | Areal Flood Warning | LWX | Anne Arundel, Baltimore, Howard, City of Baltimore | 5 hr |
| Sep 1, 4:50 AM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Baltimore, City of Baltimore | 40 min |
| Sep 1, 5:41 AM EDT | Areal Flood Warning | LWX | Cecil, Harford | 5 hr |
| Sep 1, 6:15 AM EDT | Areal Flood Warning | LWX | Cecil | 5 hr |
| Sep 1, 8:39 AM EDT | Flash Flood Warning | LWX | Allegany, Garrett | 5 hr |
| Sep 1, 10:14 AM EDT | Coastal Flood Advisory | LWX | Anne Arundel, Baltimore, Calvert, Cecil, Harford, Saint Mary's and 1 more | 19 hr |
| Sep 1, 12:52 PM EDT | Areal Flood Warning | LWX | Allegany | 22 hr |
| Sep 1, 1:11 PM EDT | Tornado Warning | LWX | Charles, Prince George's | 34 min |
| Sep 1, 1:23 PM EDT | Tornado Warning | LWX | Charles | 17 min |
| Sep 1, 1:30 PM EDT | Areal Flood Warning | LWX | Carroll, Frederick, Washington | 27 hr |
| Sep 1, 1:31 PM EDT | Tornado Warning | LWX | Charles, Saint Mary's | 29 min |
| Sep 1, 1:46 PM EDT | Areal Flood Warning | LWX | Allegany, Garrett | 16 hr |
| Sep 1, 1:56 PM EDT | Tornado Warning | LWX | Anne Arundel, Prince George's | 34 min |
| Sep 1, 2:12 PM EDT | Tornado Warning | LWX | Baltimore | 33 min |
| Sep 1, 2:23 PM EDT | Tornado Warning | LWX | Baltimore | 15 min |
| Sep 1, 2:26 PM EDT | Flash Flood Warning | LWX | Carroll, Frederick | 6 hr |
| Sep 1, 2:26 PM EDT | Tornado Warning | LWX | Baltimore, Harford | 14 min |
| Sep 1, 2:27 PM EDT | Tornado Warning | LWX | Anne Arundel | 15 min |
| Sep 1, 2:48 PM EDT | Tornado Warning | LWX | Baltimore, Harford | 27 min |
| Sep 1, 3:10 PM EDT | Tornado Warning | LWX | Baltimore | 16 min |
| Sep 1, 3:17 PM EDT | Tornado Warning | LWX | Harford | 28 min |
| Sep 1, 3:25 PM EDT | Flash Flood Warning | LWX | Carroll, Frederick | 5 hr |
| Sep 1, 3:34 PM EDT | Flash Flood Warning | LWX | Cecil, Harford | 3 hr |
| Sep 1, 3:36 PM EDT | Wind Advisory | LWX | Allegany, Carroll, Frederick, Washington | 7 hr |
| Sep 1, 3:49 PM EDT | Tornado Warning | LWX | Cecil, Harford | 26 min |
| Sep 1, 4:13 PM EDT | River Flood Watch | LWX | Cecil | 7 hr |
| Sep 1, 4:13 PM EDT | River Flood Warning | LWX | Allegany | 7 hr |
| Sep 1, 4:14 PM EDT | River Flood Warning | LWX | Allegany | 9 hr |
| Sep 1, 4:37 PM EDT | Areal Flood Warning | LWX | Baltimore, Carroll, Harford | 13 hr |
| Sep 1, 5:46 PM EDT | Tornado Warning | LWX | Cecil | 29 min |
| Sep 1, 6:08 PM EDT | Areal Flood Warning | LWX | Cecil, Harford | 17 hr |
| Sep 1, 6:12 PM EDT | Tornado Warning | LWX | Cecil | 19 min |
| Sep 1, 7:03 PM EDT | Coastal Flood Warning | LWX | Anne Arundel | 8 hr |
| Sep 1, 7:27 PM EDT | Areal Flood Warning | LWX | Allegany, Washington | 15 hr |
| Sep 1, 7:59 PM EDT | Areal Flood Warning | LWX | Carroll, Frederick | 2 hr |
Nearby
River Flood Warnings in Maryland, 2021Every 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.