No rain fell in the basin over the past 24 hours. Rainfall is expected over the next 3 days according to the Middle Atlantic River Forecast Center, ranging from 0.1 to 1 inch. The National Weather Service’s 7-day forecast predicts additional rainfall over the course of the next week, with 7-day totals up to 1 ¼ inches in some areas.
Recent basin-wide average precipitation (above Little Falls):
(based on CO-OP's Low Flow Forecast System analysis of Middle Atlantic River Forecast Center (MARFC) gridded multisensor precipitation estimates)
Yesterday's area-weighted average basin precipitation: 0 (inches)
Past 3-day cumulative area-weighted average basin precipitation: 0 (inches)
Past 7-day cumulative area-weighted average basin precipitation: 0.04 (inches)
Daily flows:
Little Falls gage flow 2023-08-22: 587 MGD (908 cfs)
Little Falls gage flow 2023-08-23: 552 MGD (est., based on recently available real-time data) (854 cfs)
Note: Gage flow at Little Falls is measured after water supply withdrawals.
Point of Rocks flow 2023-08-22: 821 MGD (1270 cfs)
Point of Rocks flow 2023-08-23: 808 MGD (est., based on recently available real-time data) (1250 cfs)
Yesterday's Washington metropolitan area Potomac River withdrawals and discharges (2023-08-22):
Fairfax Water Corbalis withdrawal (Potomac): 129 MGD
WSSC Water Potomac withdrawal: 141 MGD
Washington Aqueduct withdrawal: 144 MGD
Loudoun Water withdrawal: 5 MGD
Loudoun Water Broad Run discharge: 6 MGD
Total Potomac withdrawal: 419 MGD
Total net Potomac withdrawal: 413 MGD
Loudoun Water Potomac River (PR) flow values for drought operations protocol (based on yesterday's flows):
QPR: 1270 cfs
QPR, obs: 1270 cfs
QPR, WS: 0 cfs
Note to Loudoun Water: See NWS ensemble flow forecasts (HEFS, GEFS, NAEFS) for Point of Rocks flow for the next 7 days – see https://www.weather.gov/erh/mmefs_marfc?id=PORM2&model=NAEFS.