Extreme weather with fires in California and snow falling in the Deep South

Since we had the good start with snowfall in early November of 8.8 inches, we haven’t seen much of the white stuff since. As of today, a total of 9.6 inches of snow has fallen at Cliff’s station in Coeur d’Alene. That is below the normal of close to 15 inches for the date.

As mentioned in a previous article, when our area gets the early snowfall from late October or early November, Cliff discovered from his records that we often see the dry, foggy and cold conditions over 75 percent of the time for the following six weeks. There is a strong ridge of high pressure locked in over the western states that’s holding out the Pacific storms. Cliff and I do see a chance of snow in front of the Christmas holiday. However, we’re not going to see the big totals like we did over the past two years.

Based on Coeur d’Alene’s climatological data going back to 1895, when the high pressure ridge finally breaks down, the storm door opens up and that’s when we often see above normal snowfalls. We think that January will be a good month for snow across the Inland Northwest.

But, once again, these are crazy weather patterns. That big high pressure system is keep us dry and sending frigid air over the top and into the southern U.S. where they saw some of snowiest conditions in years. Late last week, a rare and “historic” snowstorm resulted in big pileups of cars on roadways in San Antonio, Texas. Houston saw its first measurable snowfall last Friday since Dec. 4, 2009. About 6 inches of snow fell in north Georgia as temperatures were near the freezing mark during the afternoon hours. Jackson, Miss., reported its fourth snowiest day in history on Dec. 8 as nearly 5 inches of the white stuff was reported. In Baton Rouge, La., last Friday was the 22nd day in the city’s history that has seen measurable snowfall since 1892. Snow also fell near New Orleans. Cliff tells me that snowflakes were seen down into northern Mexico last Friday.

Once the storm passed, black ice formed creating more problems for drivers in the Southeast. About 3 to 6 inches of snow fell from the East Coast down into southern Virginia.

We’ve all heard about the out-of-control wildfires in Southern California and the icy weather in the southern U.S. Since the blazes began about a week ago, about 200,000 acres have been burned. Raging infernos from Ventura, Los Angeles, Santa Barbara and San Diego counties have forced nearly 200,000 residents from their homes.

The strong ridge of high pressure locked in over the West has helped to create the very strong winds in Southern California. Many of us know about the “Santa Ana” winds that were gusting up to 80 miles per hour. By the way, a Category 1 hurricane has a wind speed of 74 mph.

With the big high situated over the interior portions of the western states, there is lower pressure over the Pacific Ocean. When there is a big difference in air pressure, winds will rush from high to low. In Southern California, the air gets funneled through the canyons and passes and become stronger. The passes include the Soledad Pass, the Cajon Pass and the San Gorgonio Pass

The Santa Ana winds are also a drying wind as they move down from the mountain to the lower elevations. The down-slope winds dramatically lower humidity levels and raise the temperature. The dry air mass, low humidity, warm air mass and the high wind speeds will usually dry out the vegetation making the region vulnerable to these wildfires.

This particular outbreak of wildfires from a Santa Ana wind event in Southern California is the worst since 2007. During that year, wildfires destroyed thousands of homes and killed 10 people. The winds helped to expand numerous fires in the cities of San Bernardino, San Diego and Los Angeles.

Some of the strongest Santa Ana winds ever recorded happened in December of 2011. The towns of Pasadena and Altadena in the San Gabriel Valley reported “sustained” winds at 97 mph. That was the equivalent of a Category 3 hurricane. There was a wind gust of 167 mph which knocked down thousands of trees and power was out in parts of that area for over a week in December of 2011.

In addition to Southern California, the winds were also very strong in Utah. Mammoth Mountain reported a wind gust of a whopping 175 miles per hour on Dec. 1, 2011.

Next week, I’ll give an update on the cooler La Nina sea-surface temperature event.

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Contact Randy Mann at [email protected]