Michigan weather: Early March Arctic blast -- what it means for the rest of month

March 2019 temperature outlook map (NOAA)
March 2019 temperature outlook map (NOAA)

By the end of this weekend, the latest Arctic blast will be on its way across the Great Lakes, and you’ll be wondering where in the world spring is.  

Before getting to the outlook for the rest of this month, I want to offer a bit of perspective.  

Our long-term average high in early March is in the low 40s, and is in the mid-20s for overnight lows. By the end of the month, those averages rise to the low 50s and mid-30s. But more important than those actual numbers is the fact that they are AVERAGES over a 30-year period of time. Those years included warm days, and cold days, and we see some pretty wild swings in our temperature records in spring (and fall).  

For example, let’s look at the history of March 8: That date’s record low is -1, set in 1943. Meanwhile that day’s record high is 80 degrees, set in 2000 (by the way, that’s the earliest 80-degree day in recorded Detroit weather history).

So having winter temperatures and snow is by no means unusual in March, which is no comfort to those Detroiters that endured 30.2 inches of snow in March 1900. And then there’s March 2010, when we had no measureable snow.

Alright, so what’s ahead after this incoming Arctic blast? Well, that’s a difficult question, because the El Niño that developed in the Pacific Ocean this winter ended up being a very weak one, with little impact on the overall jet stream pattern over North America.  Were this a more impactful El Niño, then we’d likely have a milder March. But this El Niño just isn’t doing the job, so other atmospheric and oceanic circulation patterns have become bigger players.  

Overall, after this Arctic blast, the jet stream pattern should relax, and temperatures should get closer to average.  

So, for the month as a whole, we’re expecting below average temperatures. But remember that those average highs go up a lot this month, so being below average later this month will still feel a lot better than it does now.  

As for precipitation, the pattern isn’t as clear, so we’re less certain about if we’ll end up above or below average -- but we probably won’t end up too far on either side of average.

Just to show you graphically what I’ve just explained, here are the official forecasts from the Climate Prediction Center’s website:




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