Storm Impacting the Northwest U.S.; Fire Weather Conditions in Southern California; Severe Weather in the South

A Pacific storm is bringing areas of low elevation rain, moderate to heavy mountain snow, and high winds to the Northwest. Strong Santa Ana winds and very dry conditions are producing elevated to critical fire weather conditions in southern California. Isolated strong to severe thunderstorms are possible through early Wednesday morning across parts of northeast Texas into western Tennessee. Read More >

A La Niña Watch has been issued by the Climate Prediction Center. There is a 50-55% chance of La Niña conditions developing this fall and continuing through the winter.

Learn more about:

Below is a map of the typical effect La Niña has on the November-March temperatures in the United States. The yellow and orange colors indicate areas where temperatures often average warmer than normal during a La Niña winter:

La Nina temperature anomalies

Here is a map showing the typical effect La Niña has on November-March precipitation. The blue and green colors in the Ohio Valley indicate a tendency toward wetter than normal conditions:

La Nina precipitation anomalies

It is important to remember:

The influence of La Niña on the Ohio Valley is not very strong
Every La Niña is different, and not all La Niña winters behave the same way
The strength of the La Niña may make a difference in how it affects our weather both in terms of precipitation and temperature (so far, this La Niña is expected to be weak)
There are myriad factors that work together to result in the weather we experience -- La Niña is just one of them