July 3, 2014 in Washington Voices

Randy Mann: El Nino means parts of U.S. should see more rain

 

June was an active month weatherwise across the Inland Northwest.

We had five days last month with thunderstorm activity at the Spokane International Airport and in Coeur d’Alene. The total precipitation for June was 1.84 inches in Spokane, compared to a normal of 1.25 inches. In Coeur d’Alene, 4.6 inches of moisture was reported.

As I mentioned last week, a new El Nino has formed in the south-central Pacific Ocean. The latest information indicates that sea-surface temperatures along the west coast of South America and along the equatorial regions continue to climb. Based on the current data, it appears that we’re in at least a weak El Nino pattern, but it’s quite possible it could be declared a moderate event soon.

This warmer-than-normal ocean temperature pattern will often increase rainfall in the southern U.S. and across the eastern Great Plains and Corn Belt states during the spring. We’ve already seen flooding rains in western Texas and across parts of the central U.S. But, there is a big ridge in the western U.S. that is still forecast to expand and move eastward later this month that could stress the grains and soybeans in the nation’s midsection. We’ve already seen readings near 110 degrees in Texas with this hotter weather expected to move northward and eastward within the next several weeks.

By the late summer and early fall, as El Nino becomes more influential, moisture should dramatically increase in the southern portions of the country. Even drought-ravaged California and the Southwest should see welcome rainfall later in the fall. During El Ninos, California will often receive flooding rains from the stronger subtropical jet stream.

Some scientists believe that the new El Nino will not be strong enough to pull California out of its drought. Historical records show that weak or moderate El Ninos have had little impact on winter weather. A strong El Nino, by contrast, has led to very wet winters in California. In the big El Nino season of 1997-98, San Francisco received nearly 50 inches of rain and experienced widespread flooding.

In our region, an El Nino often leads to a wetter-than-normal fall and much less snow during the winter as the air is milder from the influence of the warmer waters.

Contact Randy Mann at www.facebook.com/ wxmann, or go to www.longrange weather.com for additional information – or follow him on Twitter, @MannWeather, for forecasts and other facts.


There is one comment on this story. Click here to view comment >>

Get stories like this in a free daily email