KXO Radio AM1230 and FM 107.5

West winds are common in the Imperial Valley from March through May each year. In many years, one of three days will have west winds.  For most cities in the United States, March is windiest month of the year,  followed by April.

During March and April , as the length of the day increases and the sun rises higher in the sky ,  the temperature across the Southern United States begin to warm.  The average afternoon temperature, in the Imperial Valley during the last two weeks of March, is in the low 80s.  Over northern Canada, the sun is still low and temperatures remain cold. There is a huge temperature gradient between the Southern United States and the Canadian Arctic. Weather circulations, coming in from the Pacific, help to relieve this temperature gradient bringing the cold Canadian air south and the warm air from Southern United States northward.  The incoming Pacific weather circulations can cause some rain in the Imperial Valley during March but less so in April and May.  The main feature of the incoming spring weather systems their strong west winds. Most of the time the actual center of the weather circulations move inland from the ocean over Northern and Central California, which means the Imperial Valley is on the southern edge of the weather systems.   As the weather systems pass by they cause strong winds to blow in from the ocean, over the mountains of San Diego County down into the Imperial Valley. Slow moving  weather systems can cause the west winds to blow  for up to three days.  There is a local weather sign you can use to help predict west winds. During the spring, look towards the mountains of San Diego County, in the morning. When you see the clouds hugging the mountain ridge top and seem to be trying to spill over into the deserts, that's a good indicator that there will be west winds that day.

When the speed of the wind reaches 35 miles per hour, it begins to cause blowing sand and dust. The National Weather Service has a criteria for issuing warnings for strong winds. For the Southern California mountains below 7000 feet  and the Imperial Valley, a WIND ADVISORY is issued for forecasted sustained wind speeds of 35 mph or more and/or winds gusts of 45 mph or more.  A HIGH WIND WARNING means even stronger winds and is issued for sustained winds of 45 mph or more with gusts to 58 mph or more.

The west winds bring in fresh cooler air from the Pacific.  In late May and June, the weather systems coming in from the Pacific usually track inland further away to the north and the number of days with west winds decreases and the hotter weather begins in the Imperial Valley. It would be nicer if the cooling west winds would continue during June through August. From mid September into October, the Pacific storm track edges south and closer again bringing a welcome west wind and cooler temperatures.

Jim Christopherson

Jim Christopherson has a long history with Imperial Valley Radio; he has been giving weather reports since 1976. Jim began his weather career as a forecaster for the United States Air Force and he retired as a forecaster from the National Weather Service in 1996.