If April showers bring may flowers, then what does March heat bring? Many of you may have heard of Seasonal Affective Disorder, when people become sad or depressed from dreary winter weather. Considering all the change-ups Mother Nature has been throwing our way, many of you may be experiencing another version of SAD, or Seasonal Adjustment Disorder! Looking at the latest 90-Day Temperature Outlook issued by the Climate Prediction Center, we can see that the above normal temperatures aren’t going away anytime soon as much of the Eastern and Southwestern U.S. is forecast to remain above normal.
March has been plagued with everything from record setting severe weather events to high temperatures, and even plenty of Western snowfall. Just since last Monday, there have been 1192 high temperature records set or broken across the U.S., and the forecast for the next several days doesn’t show any reprieve from these record setting highs as parts of the Great Lakes and Upper Midwest see highs 30-40° above normal! Taking a closer look at folks who have seen some record breaking heat, we find that Chicago recently had high temperatures at or above 80° for 5 consecutive days, setting a record for the most 80°+ days during any March. They also saw the warmest St. Patrick’s Day ever since records began in 1872. Records were set again Sunday from the Deep South and up through the Upper Midwest, with even Fargo, ND reaching 83°!
While temperature records have been shattered across the Central and Eastern U.S., the West has been plagued with just the opposite, heavy rain and snow. A heavy snowstorm impacted the Southwestern U.S. over the weekend and up to 3 feet of snow fell across northern Arizona, with Arizona Snowbowl Ski Resort reporting 36” of snow! Check out some of the totals seen across other locations.
So what is responsible for all these extremes? The Jetstream. La Nina has almost completely returned to neutral conditions, so this is not technically a continued result of La Nina. For the past week and a half, there has been a persistent ridge across the Eastern U.S. and a trough across the Western U.S. The trough in the West is allowing colder Canadian air to filter into those regions, while the ridge over the East Coast is allowing very warm, moist air from the Gulf of Mexico to reach as far north as the Upper Midwest, as depicted below.
The very warm winter the country saw in 2011-2012 ended up being the 4th warmest on record, and this could be a factor which has lead to our above normal temperatures in the East as mild winter kept the Gulf waters warmer than normal. This may have acted as a massive heat pump across the Eastern U.S., not only contributing to the record highs, but also to the strong storms seen earlier this month. The Gulf provides lots of warm, moist air that clashes with cooler air coming down from Canada. When you combine these ingredients with a strong jetstream, severe storms and tornadoes can be the result, and more of that can be expected Monday across the Southern Plains.