Trace amounts of precipitation occurred around the outer perimeter of the basin, resulting in an average basin precipitation of 0.016 inches for yesterday. According to MARFC, the basin precipitation for the month of October is currently at 1 inch, which is about normal for this time of the month. Above the USGS gage at Point of Rocks, this precipitation has returned some of the precipitation totals to near normal or above normal for the month. However, below this USGS gage, greater than 75% below normal precipitation totals for the month remain throughout the basin. The 5-day and 7-day MARFC forecast calls for 0.5 to 0.75 inches of possible precipitation.
Although flows at the USGS gage at Point of Rocks are currently above 2000 cfs, the trigger for daily monitoring, daily monitoring will be continued at this time.
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 precip: 0.01585 (inches)
Past 3-day cumulative area-weighted average basin precip: 0.01585 (inches)
Past 7-day cumulative area-weighted average basin precip: 1.0971 (inches)
Daily Flows:
Little Falls gage flow 2019-10-12: 1280 MGD (1980 cfs)
Little Falls gage flow 2019-10-13: 1312 MGD (est., based on recently available real time data) (2030 cfs)
Note: Gage flow at Little Falls is measured after water supply withdrawals.
Point of Rocks flow 2019-10-12: 1409 MGD (2180 cfs)
Point of Rocks flow 2019-10-13: 1351 MGD (est., based on recently available real time data) (2090 cfs)
Yesterday's Net Potomac withdrawal (2019-10-12):
FW Corbalis withdrawal (Potomac): 101 MGD
WSSC Potomac withdrawal: 174 MGD
Aqueduct withdrawal: 142 MGD
Loudoun withdrawal: 10 MGD
Total Potomac withdrawal: 427 MGD