There was a significant storm over the majority of the basin yesterday. Most locations received 0.75 to 1.5 inches of rain; other locations received as much as 2 to 3 inches of rain. The National Weather Service 48-hour forecast predicts between 0.1 and 0.25 inches of rainfall over much of the basin. The 5-day Quantitative Precipitation Forecast indicates a chance of 0.75 to 1.6 inches of rainfall over much of the basin.
Many of the USGS gages are still not currently reporting flow for yesterday (8/12) and so yesterday's average flow has been estimated from real-time information. Little Falls flow reached 3,018 MGD (4,750 cfs) but is dropping at a fast rate. Point of Rocks flow increased but is still under the 2,000 cfs threshold for daily monitoring.
Daily Flows:
Little Falls gage flow 08/12: 1370 MGD (2110 cfs)
Little Falls gage flow 08/13: 1680 MGD (est., based on recently available real time data) (2600 cfs)
Note: Gage flow at Little Falls is measured after water supply withdrawals.
Point of Rocks flow 08/12: 1000 MGD (1550 cfs)
Point of Rocks flow 08/13: 1140 MGD (est., based on recently available real time data) (1760 cfs)
Yesterday's Net Potomac Production (08/12/10):
FW Corbalis raw water withdrawal (Potomac): 127 MGD
WSSC Potomac Production: 157 MGD
Aqueduct withdrawal: 179 MGD
Total Potomac demand: 463 MGD