Monitoring Reports

There has been significant rainfall in the DC metropolitan area over the past couple of days, but only approximately 1/4 of an inch in the western portion of the Potomac River basin. The Middle Atlantic River Forecast Center predicts 1/10 to 1/2 of an inch across the southern half of the basin over the next 48 hours, including in the South Branch and Shenandoah areas. The 5-day Quantitative Precipitation Forecast indicates a chance of up to 1 inch of rain across the entire basin.

Significant rain fell in the southeastern portion of the Potomac River basin yesterday, with the heaviest accumulations occurring near the DC metropolitan area. More rain is expected today, and the Middle Atlantic River Forecast Center predicts between 1/4 to 3/4 of an inch in the southern basin, including the DC area and parts of the Shenandoah. Though the recent rainfall has caused Potomac River flow at Little Falls to increase significantly, flows remain low in many upstream tributaries.

There were scattered showers and thunderstorms in the southeastern part of the Potomac River basin yesterday. The National Weather Service predicts heavy rain tomorrow throughout the region with possible accumulations ranging from 2 inches in the southeastern portion of the basin to an inch in the northwest.

There were scattered showers and thunderstorms in the basin yesterday, with accumulations of 0.25 to 0.50 inches in few localized areas. The National Weather Service's Middle Atlantic River Forecast Center predicts accumulations of up to 0.25 inches in parts of the basin, including the Shenadoah and Monocacy sub-basins, over the next 48 hours, and up to 0.5 inches in Washington, DC and surrounding areas. The 5-day quantitative precipitation forecast shows a chance of up to 1.5 inches of accumulated rainfall in the southeastern portion of the basin.

Yesterday there was scattered precipitation across the basin that produced approximately 0.25 to 0.50 inches of rain in the headwaters area, according to the National Weather Service's Middle Atlantic River Forecast Center . Over the next 48 hours, the River Forecast Center predicts an accumulation of up to 0.5 inches of precipitation. The 5-day Quantitative Precipitation Forecast shows a chance of up to 1.5 inches of accumulated rainfall.

Potomac River flows at Point of Rocks and Little Falls have risen due to the recent storms in the eastern portion of the basin. The National Weather Service's Middle Atlantic River Forecast Center reports 1/2 inch to 3/4 inches of rain in a few locations in the eastern part of the basin over the past 24 hours, and predicts accumulations of between 1/4 and 1/2 inches in the watersheds of the North and South Branches of the Potomac over the next 48 hours.

There was a significant storm over the majority of the basin yesterday. Most locations received 0.75 to 1.5 inches of rain; other locations received as much as 2 to 3 inches of rain. The National Weather Service 48-hour forecast predicts between 0.1 and 0.25 inches of rainfall over much of the basin. The 5-day Quantitative Precipitation Forecast indicates a chance of 0.75 to 1.6 inches of rainfall over much of the basin.

There was a significant storm over the northeast portion of the basin this morning with up to 2 inches of rain seen in some locations. The National Weather Service 48-hour forecast predicts 0.25 inches in the western areas of the basin and up to 1 inch in the eastern portion. The 5-day quantitative precipitation forecast indicates a chance of over 2 inches of accumulated rainfall over much of the basin. Many of the USGS gages are not currently reporting flow for yesterday and have not been updated with real-time information since around 1:00 am this morning.

There was no rainfall in the Potomac River Basin over the past 24 hours. National Weather Service forecasts predict accumulations of 1/10 to 1/4 inches of rain over the next 48 hours in portions of the Potomac Basin. The Mid-Atlantic River Forecasting Center quantitative precipitation forecasts (qpfs) indicate that the entire Basin will receive amounts between 1 and 1.5 inches over the next 5 days. USGS real-time data show a steep drop in flow at Little Falls this morning.

There was no significant rainfall in the Potomac River basin over the past 24 hours. National Weather Service forecasts predict 1/10 of an inch of rain over the next 48 hours in portions of the Potomac basin. The Mid-Atlantic River Forecasting Center quantitative precipitation forecasts (qpfs) indicate that the entire basin will receive amounts between 1 and 1.75 inches over the next 5 days. The U. S. Geological Survey observed flows suggest that flow at Little Falls will hold steady for the next couple of days.