Potomac River flow at Point of Rocks is hovering around 2000 cfs, the trigger for CO-OP daily drought monitoring. It should be noted that flows in the river are not particularly low for this time of year - 2000 cfs is close to the median flow at Point of Rocks in mid-September. The National Weather Service forecast calls for little rain over the next seven days.
This concludes the 2017 Washington Metropolitan Area (WMA) Drought Exercise - thank you for your support of WMA drought preparedness!
Actual daily drought monitoring continues, so suppliers please continue to submit your withdrawal data every morning.
DROUGHT EXERCISE - Afternoon Potomac flow and demand update (Wednesday 8/13/2017) - DROUGHT EXERCISE
NOTE: In our twice daily reports for the 2017 exercise we will be reporting ACTUAL basin flows and system withdrawals, and SIMULATED recommended operations.
Over the past 24 hours, accumulations of rain of up to an inch were recorded in scattered areas, in the northwestern portion of the basin. According to the Middle Atlantic River Forecast Center's quantitative precipitation forecasts, between zero and 1/2 of an inch is expected over the next 72 hours, mainly in the northern portion of the basin.
Little rain fell on the basin over the past 24 hours. According to the Middle Atlantic River Forecast Center's quantitative precipitation forecasts, between zero and 3/4 of an inch of rain is expected throughout the basin over the next 72 hours.
There was no significant rainfall in the basin over the last 24 hours. The National Weather Service predicts basin-wide average accumulations of approximately 1 to 3 inches over the next 2 days and significant rises in flow at the Point of Rocks and Little Falls gages over the next week.
Up to 0.25 inch of rain fell in western portions of the basin over the the past 24 hours. The Middle Atlantic River Forecast Center predicts 0.75 to 2 inches of rain over the next 3 days.
A limited area in southwestern portion of the basin received a half to one inch of rain over the past 24 hours. Other areas in the southern half of the basin received up to a quarter of an inch. Accumulated rainfall predictions over the next three days remain the greatest to the south. Today's prediction ranges from 0.01 to 0.75 inches.
A white water release has begun from Savage Reservoir. It will conclude early this evening.
A negligible amount of rain fell in the basin yesterday. MARFC continues to show some chance of rain through the weekend. Between 0.01 and 0.50 inches are possible today in the southern portion of the basin. The chance of rain extends north on Saturday and Sunday. Accumulated rainfall may reach 1.50 inches to the south. The northern areas may see a 3-day accumulation between 0.10 and 0.50 inches.
Last weekend's artificially varied flow release is now passing Little Falls.
A negligible amount of rain fell in the basin yesterday. MARFC indicates some chance of 0.01 to 1.00 inch of rain Friday and Saturday. The heavier rain is expected to the southwest.
Up to 0.75 inches of rain fell in western areas of the basin yesterday. MARFC predits up to an inch of rain across the basin over the next three days.
Daily Flows:
Little Falls gage flow 09/20: 900 MGD (1390 cfs)
Little Falls gage flow 09/21: 810 MGD (est., based on recently available real time data) (1260 cfs)
Note: Gage flow at Little Falls is measured after water supply withdrawals.
Point of Rocks flow 09/20: 1020 MGD (1580 cfs)
Point of Rocks flow 09/21: 1000 MGD (est., based on recently available real time data) (1540 cfs)