The National Water Model (NWM) forecasts streamflow over the entire continental United States. The system models physical processes such as snowmelt and infiltration to determine how much precipitation forecast by NWS will become runoff, then route that runoff through the river network to simulate discharge levels.
Explore graphs and maps of historical and projected temperature and precipitation variables for any county in the contiguous United States. Additionally, view graphs from individual weather stations and coastal tidal gauges.
View monthly maps showing the probability for precipitation ranking in the top, middle, or bottom third of historical observations. Outlooks that favor drier or wetter periods can raise awareness of the potential for changing conditions.
The National Hurricane Center monitors marine weather and indicates the chance that disturbances will develop into tropical storms. For storms that do develop, the site shows predicted paths and storm status. Monitor this site to be aware of the potential for tropical storms and/or hurricanes.
Check the probability that cumulative rainfall will exceed user-defined thresholds within the next three days during 6- to 24-hour intervals. This forecast can serve as an early alert for potential flooding.
This interactive map shows regions where the risk of having a seasonal extreme in temperature or precipitation is elevated during El Niño or La Niña conditions. Decision makers can identify areas that have an increased or decreased risk of extreme warm/cold (or dry/wet) seasons, and plan accordingly.