A warm front moved through the area during the morning hours of the 28th. Warm and moist air associated with a tropical air mass overran the relatively cooler air in place, resulting in heavy rainfall. Also, the steering flow aloft was weak so showers and thunderstorms were slow to move. This enhanced the flooding threat.  The resulting flooding moved into larger streams and rivers and continued through the 30th.

Flood in WASHINGTON, MARYLAND
From 28-SEP-18 02:40:00 to 28-SEP-18 04:40:00 (EST-5)
Location: PECKTONVILLE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

The 13200 block of Pectonville Road was closed due to flooding.

Flood in WASHINGTON, MARYLAND
From 28-SEP-18 02:41:00 to 28-SEP-18 04:41:00 (EST-5)
Location: ASHTON
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Ashton Road was closed at Gruber Road due to flooding.

Flood in MONTGOMERY, MARYLAND
From 28-SEP-18 06:09:00 to 28-SEP-18 08:09:00 (EST-5)
Location: BRIGHTON
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

The EM reported Brighton Dam Road closed due to flooding near New Hampshire Avenue.

Flood in WASHINGTON, MARYLAND
From 28-SEP-18 01:05:00 to 28-SEP-18 09:21:00 (EST-5)
Location: PEARRE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The USGS stream gage on Sideling Hill Creek near Bellegrove exceeded the 7.5 foot flood stage during the indicated period, flooding lowlands and farmlands near the creek. The peak level of 8.76 feet occurred at 4:15am EST.

Flood in MONTGOMERY, MARYLAND
From 29-SEP-18 01:00:00 to 30-SEP-18 08:54:00 (EST-5)
Location: KENWOOD
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The USGS stream gage on the Potomac River near Little Falls Dam exceeded the 10 foot flood stage during the indicated period, flooding lowlands and trails near the C&O Canal. The peak level of 11.01 feet occurred at 4:45pm EST on the 29th.

Flood in BALTIMORE, MARYLAND
From 28-SEP-18 04:06:00 to 28-SEP-18 08:12:00 (EST-5)
Location: GLENCOE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The water levels at Gunpowder Falls at Glencoe surpassed flood stage of 7 feet. The water levels crested at 8.47 feet at 6:00 AM September 28th.
Portions of Upper Glencoe Road and Lower Glencoe Road began to flood.

Flood in CARROLL, MARYLAND
From 28-SEP-18 01:24:00 to 28-SEP-18 03:22:00 (EST-5)
Location: KEYMAR
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The USGS stream gage on Big Pipe Creek near Bruceville exceeded the 8 foot flood stage during the indicated period, flooding Keysville-Bruceville Road. The peak level of 8.40 feet was observed at 2:15 am EST.

Flood in WASHINGTON, MARYLAND
From 28-SEP-18 02:42:00 to 28-SEP-18 04:42:00 (EST-5)
Location: PECKTONVILLE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

The 10400 block of Catholic Church Road was closed due to flooding.

Flood in WASHINGTON, MARYLAND
From 28-SEP-18 02:44:00 to 28-SEP-18 04:44:00 (EST-5)
Location: CORBETT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

West Memorial Boulevard was closed at the railroad underpass due to flooding.

Flood in FREDERICK, MARYLAND
From 28-SEP-18 03:43:00 to 28-SEP-18 05:43:00 (EST-5)
Location: PARK MILLS
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

The 8100 block of Peters Road was closed due to flooding.

Flood in FREDERICK, MARYLAND
From 28-SEP-18 03:45:00 to 28-SEP-18 05:45:00 (EST-5)
Location: BOLIVAR
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Shank Road was closed at Alternate Route 40 due to flooding.

Flood in ANNE ARUNDEL, MARYLAND
From 28-SEP-18 01:20:00 to 29-SEP-18 01:11:00 (EST-5)
Location: RAYNOR HGTS
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The stream gauge on the Patapsco River at Elkridge exceeded the 16 foot flood stage during the indicated period. Hammonds Ferry Road flooded and was closed at the Patapsco River. Backwater flooding led to the closure of Furnace Avenue in Elkridge. The peak level of 20.29 feet occurred at 10:40 AM on the 28th.

Flood in WASHINGTON, MARYLAND
From 28-SEP-18 06:37:00 to 29-SEP-18 00:03:00 (EST-5)
Location: FAIRVIEW
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The stream gauge along the Conocochague Creek surpassed the flood stage of 10 feet. the gauge crested at 11.08 feet at 1:00 PM EST September 28th. Wishard Road and Kemp Mill Road were both flooded.

Flood in FREDERICK, MARYLAND
From 28-SEP-18 03:48:00 to 28-SEP-18 05:48:00 (EST-5)
Location: CATOCTIN
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

The 3500 Block of Sigler Road was closed due to flooding.

Flood in FREDERICK, MARYLAND
From 28-SEP-18 16:15:00 to 30-SEP-18 09:18:00 (EST-5)
Location: BRUNSWICK
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The river level surpassed the flood stage of 16 feet at Point of Rocks along the Potomac River. The river level crested at 21.39 feet at 11:30 AM EST September 29th.
The boat ramp and lower parking lot at Point of Rocks was flooded. Water approached the water treatment plant in Brunswick. Farmland behind the Tarara Vineyard was flooded. Water approached structures at the Brunswick campground. Water entered the comfort station at the Brunswick boat ramp parking area. The parking lots at both the McKimmey and Brunswick boat ramps were flooded. Flooding of an agricultural field adjacent to the McKimmey boat ramp occurred. About half the lower parking lot of the Point of Rocks boat ramp was also flooded.

Flood in MONTGOMERY, MARYLAND
From 28-SEP-18 00:21:00 to 28-SEP-18 07:46:00 (EST-5)
Location: SENECA
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The USGS stream gage on Seneca Creek near Dawsonville exceeded the 7.5 foot flood stage during the indicated period. The peak level of 8.26 feet was observed at 2:55 AM EST. Berryville Road was closed due to flooding between Seneca Road and Finnegan Farm Road.

Flood in ALLEGANY, MARYLAND
From 28-SEP-18 12:37:00 to 28-SEP-18 23:23:00 (EST-5)
Location: KEIFER
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The river level surpassed the flood stage of 25 feet at Paw Paw along the Potomac River. The river level crested at 25.90 feet at 6:15 PM EST September 28th.
A parking area adjacent to the highway bridge was flooded. The roadway to the C&O Canal parking area flooded, as did the lowest end of the Purslane Run hiker/biker area.

Flood in FREDERICK, MARYLAND
From 28-SEP-18 03:47:00 to 28-SEP-18 05:47:00 (EST-5)
Location: MONROVIA
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Weller Road was closed at Weller Hill Drive due to flooding.

Flood in FREDERICK, MARYLAND
From 28-SEP-18 03:49:00 to 28-SEP-18 05:49:00 (EST-5)
Location: IJAMSVILLE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

The 8800 Block of Ball Road was closed due to flooding.

Flood in FREDERICK, MARYLAND
From 28-SEP-18 03:49:00 to 28-SEP-18 03:49:00 (EST-5)
Location: JEFFERSON
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

The 4300 Block of Lander Road was closed due to flooding.

Flood in HOWARD, MARYLAND
From 28-SEP-18 04:04:00 to 28-SEP-18 06:04:00 (EST-5)
Location: LISBON
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Woodbine Road was closed at Morgan-Woodbine Road due to flooding.

Flood in CARROLL, MARYLAND
From 28-SEP-18 04:11:00 to 28-SEP-18 06:11:00 (EST-5)
Location: HOUCKSVILLE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

The 3000 Block of Hofmann Mill Road was closed due to flooding.

Flood in FREDERICK, MARYLAND
From 28-SEP-18 03:43:00 to 28-SEP-18 05:43:00 (EST-5)
Location: NEW LONDON
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Gas House Pike was closed at New London Road due to flooding.