National Weather Service United States Department of Commerce

Unsettled Weather Continuing over the Western and Eastern U.S. into Mid Week

Two storm systems, one over the Desert Southwest, and one over the Ohio Valley, will continue to bring unsettled weather and cooler temperatures into the middle of the week. Moderate to heavy rainfall, along with the potential for flash flooding, is forecast from the Ohio Valley to the East Coast. Moderate to locally heavy rainfall is expected over the Northern Rockies, Great Basin and Southwest. Read More >

5-yr Running Mean Precipitation

5-yr running mean with annual precipitation

5-yr running mean with annual precipitation

 

Data from the stations below were used to create the three graphs above. Data from 1925 to 2024 were averaged for all nine stations for April to October (which represents the growing season). For the top graph, a 5-year average was used to smooth the data to help highlight the most consistent signals. Blue parts of the line denote wetter than average periods, while red parts of the line denote drier than average periods. Of interest, there is a signal for 5–10-year periods of alternating mostly wet or dry weather. For the middle graph, the raw yearly data (from the combined nine stations) are plotted as a dashed brown line on top of the 5-year average (from the top graph) to illustrate the year-to-year variability. For the third graph, temperature data (red) for the same stations and using the same methods (as for precipitation) are plotted on top of the precipitation (green) from the top graph. This shows rather well an inverse relationship between temperature and precipitation. Specifically, note how the dry 1930s epoch was the warmest period during this time, whereas the wet 1990s epoch was a relatively cool period.

Sites included to produce the running mean