Monitoring Reports

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.

Potomac River flows continue to hold relatively steady. Less than an inch of precipitation is in the cumulative forecast for the basin over the next ten days.

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: 0.14 (inches)
Past 3-day cumulative area-weighted average basin precipitation: 0.23 (inches)

In the past 24 hours, up to 0.5 inches of rain fell in localized areas of the Potomac Basin, mainly in the northwestern portions and around the Washington D.C area. According to the Middle Atlantic River Forecast Center’s cumulative forecast, no substantial rain is expected in the next 72 hours. River flow at Point of Rocks increased slightly but is still close to the 2000 cfs daily monitoring threshold.

About 0.1 inches of rain fell in the Potomac Basin yesterday, mostly in the portion of the basin below Little Falls. The Middle Atlantic River Forecast Center’s cumulative forecast calls for 0.01 to 0.10 inches over the next 72 hours. River flow at Point of Rocks continues to remain below the 2000 cfs daily monitoring threshold.