Flood Watch
2026-09-13T02:00:00-04:00

* WHAT...Flash flooding caused by excessive rainfall is possible. * WHERE...A portion of western Maryland, including the following areas, Eastern Garrett, Extreme Western Allegany and Western Garrett. * WHEN...Through late tonight. * IMPACTS...Excessive runoff may result in flooding of rivers, creeks, streams, and other low-lying and flood-prone locations. Creeks and streams may rise out of their banks. Low-water crossings may be flooded. * ADDITIONAL DETAILS... - Showers and thunderstorms are expected at times through this evening. Given the humid airmass in place, there is the potential for up to 2 inches of rain in an hour, with localized totals of up to 5 inches possible. This would result in rapid rises of water on small streams and creeks and in low-lying areas. - http://www.weather.gov/safety/flood

Realtime Data

Maryland

Explore Interactive Map

Flood Watch
Until 2026-09-13T02:00:00-04:00 • National Weather Service
* WHAT...Flash flooding caused by excessive rainfall is possible. * WHERE...A portion of western Maryland, including the following areas, Eastern Garrett, Extreme Western Allegany and Western Garrett. * WHEN...Through late tonight. * IMPACTS...Excessive runoff may result in flooding of rivers, creeks, streams, and other low-lying and flood-prone locations. Creeks and streams may rise out of their banks. Low-water crossings may be flooded. * ADDITIONAL DETAILS... - Showers and thunderstorms are expected at times through this evening. Given the humid airmass in place, there is the potential for up to 2 inches of rain in an hour, with localized totals of up to 5 inches possible. This would result in rapid rises of water on small streams and creeks and in low-lying areas. - http://www.weather.gov/safety/flood

MCMILLAN F NEAR FORT PENDLETON, MD

Realtime Data • Report • Conditions

2

Discharge (cfs)

0.5

Gauge Height (ft)

USGS 01594950

Streamflow discharge was last observed at 2 cfs, and a gauge height of 0.49 feet. With the % decrease since yesterday, the streamflow average over the past 10 days is 1 .

Weather today, Tomorrow,

There are no major dams on the river. Seasonal trends show a higher flow in the spring due to snowmelt and increased rainfall, while summer months see lower flow levels. The Patuxent River provides drinking water to over 1.6 million people in the D.C. metropolitan area. Interestingly, the river is home to a diverse array of wildlife, including bald eagles, river otters, and several species of fish. The McMillan F stream gauge is an important tool for monitoring and managing the water resources of the Patuxent River watershed.

September 12, 2026

Elevation	2,453.0 ft
Last Updated
Gage height, feet	0.49 ft
Streamflow, ft3/s	2.19 ft3/s
Percent of Normal	7%
Year Over Year Average	36 cfs
24hr Flow Prediction	cfs
Maximum Recorded	821 cfs
Geolocation	39.28, -79.39

SNOFLO^®

Mcmillan F Near Fort Pendleton, Md Realtime Data

MCMILLAN F NEAR FORT PENDLETON, MD

Realtime Data • Report • Conditions

2

Discharge (cfs)

0.5

Gauge Height (ft)

September 12, 2026

Seasonal Comparison

Oceanic Nino Index

SNOFLO®

Mcmillan F Near Fort Pendleton, Md Realtime Data

MCMILLAN F NEAR FORT PENDLETON, MD

Realtime Data • Report • Conditions

2

Discharge (cfs)

0.5

Gauge Height (ft)

September 12, 2026

Seasonal Comparison

Oceanic Nino Index

$4.99

$3.99

Per Month

SNOFLO^®