El Niño’s greatest impacts on southern Arizona typically happen between December and March. As of January 21st, you could say we’re closing in on halftime. How are we doing rainfall-wise?
Since December 1st, most southern Arizona communities have picked up at least 1.50″ rainfall & are running a rainfall surplus. This is no huge surprise, as my call from last Summer said it would likely be a wet Winter. Meanwhile in the Sky Islands, Mount Lemmon has received as much as 36″ snow. Much of this fell during a series of early January Winter storms that brought accumulating flakes as low as Oro Valley.
Not much has changed in the forecast thinking through March. I’m still inclined to agree with the Climate Prediction Center’s forecast for above average rain/mountain snow. In case you’re keeping score at home, Tucson’s average rainfall for February & March is 0.86″ and 0.73″, respectively.
Twitter follower Jack asked a couple of interesting questions regarding El Niño. While the frequency of storm systems is impossible to predict between now and late March, we have a general idea of how long these conditions will last in the eastern Pacific.
Global models show waters off the western Mexico coast gradually cooling through the Spring. Odds favor sea surface temperatures entering a “neutral” phase by May. While we may see above average rainfall last into April, we should start to see a shift toward normal in the eastern Pacific with Monsoon 2016 looming.