Monitoring Reports

Potomac River flows continue to fall. National Weather Service forecasts indicate that no rain will fall in the basin over the next three days.

Potomac River flows at Little Falls have been relatively steady for the past few days. The USGS conducted two field discharge measurements at Point of Rocks over the course of the past few days and adjusted flow values accordingly.  No rainfall is expected in the basin over the next three days.

CO-OP is reinitiating daily drought monitoring and reporting today because Potomac River flow at the US Geological Survey’s stream gage at Point of Rocks, Maryland, is approaching the 2000 cubic feet per second (cfs), CO-OP's daily monitoring threshold. According to the Middle Atlantic River Forecast Center, no rainfall is expected in the basin over the next three days.

CO-OP is suspending daily drought monitoring emails because flow at the US Geological Survey’s gage at Point of Rocks, Maryland, has risen above the 2000 cfs monitoring threshold. Yesterday, a tornado watch lasted until 9 p.m., but there were no confirmed tornadoes in the region. Some parts of the basin observed up to 1.75 to 2 inches of precipitation during this time. The Middle Atlantic River Forecast Center predicts an additional 0.1 to 1.25 inches of rainfall over the next 72 hours, possibly arriving by this Thursday.

Precipitation amounts over the past 24 hours varied from trace amounts in the middle of the basin to over an inch in some locations in far western areas and in some parts of the DC metro area.  Given the locations of the heaviest rainfall amounts, only a modest increase in flows at the USGS gage at Point of Rocks has occurred at this time.  Flows remain below the threshold for daily monitoring.

The basin received negligible rain over the past 24 hours. But the weather forecast shows some potential relief in the coming days. According to the Middle Atlantic River Forecast Center, precipitation totals ranging from 0.25 to 2 inches are expected in the next 72 hours throughout the basin.

River flows continue to slowly decline. National Weather Service forecasts indicate that there will be significant rainfall in the northern half of the basin – 0.5 to 1.5 inches - over the next three days.

The basin received negligible precipitation yesterday. According to the Middle Atlantic River Forecast Center, precipitation totals up to 0.1 inches are expected in the next three days. River Flows have been gradually decreasing over the past week.

Yesterday, there was no recorded rainfall. In the next 72 hours, 0.1 to 0.5 inches of rain are expected in the basin.

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: 0.14 (inches)
Past 7-day cumulative area-weighted average basin precipitation: 0.63 (inches)

Yesterday, there was no recorded rainfall, and the current Point of Rocks flow is estimated to be 1600 cubic feet per second (cfs).  The cumulative forecast for the basin over the next 7-10 days indicates less than an inch of rain.