With rain continuing to fall across much of the basin, flow at the Point of Rocks gage is 1,910 cfs. Over the past 24 hours, rainfall in the basin has ranged from zero in the west to 1.5 inches in the southeast. The 72-hour forecast predicts between 0.5 and 2 inches of rain across the basin, increasing from west to east.
Flows in basin streams have risen modestly due to Monday's rain event, but flow at Point of Rocks remains below 2000 cfs. National Weather Service forecasts call for more rain over the next 72 hours, though the highest accumulations are expected to be in the eastern portion of the basin.
While the entire basin received significant rainfall yesterday, flow at the Point of Rocks gage has not yet risen much. MARFC predicts that flow will rise above 2,000 cfs sometime tomorrow. The highest rainfall amounts, between 1.25 and 1.75 inches, fell in the central part of the basin. The other areas received between 0.25 and 1.25 inches. The 72-hour forecast shows a chance of 0.25 and 1.50 inches of rain, with the amounts increasing in bands from west to east.
Flow at the Point of Rocks gage dropped approximately 400 cfs over the weekend. The western portion of the basin received between trace amounts and 0.5 inches of rain over the last 24 hours. The 72-hour forecast shows a chance of 0.5 to 1.25 inches of rain across the basin. The NOAA/MARFC briefing from Sunday, October 6, indicates that this rain is from a cold front crossing the region, not from Tropical Depression Karen. The heaviest rain is expected east of the I-95 corridor.
Potomac River flows at Point of Rocks and Little Falls are still slightly higher due to last weekend's water quality releases from the North Branch reservoirs. The basin is expected to receive some precipitation - trace amounts up to a half inch - on Sunday. The Middle Atlantic River Forecast Center predicts that flow at Point of Rocks will fall to 1720 cfs over the next 72 hours.
Because flow conditions are expected to be relatively stable over the next 72 hours, CO-OP's daily drought monitoring and reporting will be suspended over the weekend, and will resume on Monday.
No rain fell in the basin over the last 24 hours and none is predicted for the next 72-hour period. The rise in flow at Point of Rocks is due to the release this weekend from the North Branch Reservoirs.
According to the National Weather Service, there was 0 to 0.25 inches of rain in the basin over the last 24 hours. A tenth of an inch of rain in the North Branch is predicted for the next 72 hours.
According to the National Weather Service, there was no rain in the basin over the last 24 hours. No rain is predicted for the next 72 hours.
Daily Flows:
Little Falls gage flow 09/30: 1110 MGD (1710 cfs)
Little Falls gage flow 10/01: 1010 MGD (est., based on recently available real time data) (1560 cfs)
Note: Gage flow at Little Falls is measured after water supply withdrawals.
Point of Rocks flow 09/30: 1170 MGD (1810 cfs)
Point of Rocks flow 10/01: 1090 MGD (est., based on recently available real time data) (1680 cfs)
Point of Rocks flow fell below 2,000 cfs over the weekend and therefore we are continuing daily monitoring. No rain fell in the basin over the last 24 hours and no rain is predicted for the next 72 hours.
Daily monitoring reports will be suspended over the weekend since flow at Point of Rocks is above the monitoring threshold of 2000 cfs. A decision on whether or not to resume daily monitoring will be made on Monday based on flow and weather conditions.