Oh, March. You’re the first month of meteorological spring, but you can still taste like winter at times. You’ve been as cold as 4 degrees (in 1873) and as hot as 93 (in 1907). We’ve seen such volatility in the past five years, too, from the warmest-on-record March in 2012 to a super snowy and cold March just two years later.
This year’s indications present a mix of competing influences, so we’re predicting near-normal temperatures and snowfall, but above-normal rain.
March express forecast
Average temperature: 44.8 to 48.8 degrees (normal: 46.8 degrees)
Precipitation: 3.25 to 4.0 (normal: 3.48 inches)
Snow: 0 to 2 inches (normal: 1.3 inches)
Temperature outlook details
February turned out much milder than expected, but we estimate March will end up closer to normal, thanks to two opposing weather influences.
High pressure building over Greenland, often called the “Greenland Block,” tends to favor colder and stormier than normal weather in our region. It is expected to be a dominating feature through the first half of the month, at least.
However, an evolving dip in the jet stream on the West Coast tends to favor milder Eastern weather. The end result of these two conflicting patterns is a tug of war between colder and milder weather regimes in our region.
Since 2000, we’ve had a mix of mild and cold Marches, but more often mild. We’ve been warmer than normal 11 times and cooler than normal seven times. This year we think we end up between the two extremes.
Precipitation outlook details
The Greenland Block tends to support more coastal storms, and we’ve got at least a couple of those lining up over the next two weeks. As a result, we think March will close slightly wetter than normal.
The National Weather Service Weather Prediction Center precipitation forecast shows a fairly wet seven days ahead even if Washington is in a slight precipitation shadow (as Thursday’s storm in the Ohio Valley skips over Washington before developing into a big nor’easter offshore):
February’s very wet weather has alleviated drought concerns to some degree, and this trend should continue at least through the first half of March.
What about snow?
Do not give up just yet, snow lovers! Last March, we managed to eke out above-normal snow, thanks to two inches in the middle of the month (March 13-14). While this Friday’s event is unlikely to produce more than some non-accumulating flakes, we’re watching another system in the middle of next week and then potentially a couple more.
It is tricky to see accumulating snow in March, as it often depends on the time of day when a weather system hits. A nighttime event can deliver better chances for accumulation, but events during the day tend to struggle because our normal temperatures are getting so high.
Two interesting things about recent March snow trends: 1. March snowfall since 2000 has been higher than normal and 2. We’ve had measurable March snow for the past four years. So while we don’t see a well-defined snow threat yet, we’ll definitely need to watch this series of storms over the next two weeks.
Additional inputs into our March outlook
CFS model leans warm and wet. The National Oceanic and Atmospheric Administration CFS model indicates that the milder Pacific Ocean influences on our weather will slightly win out in March. Our outlook is hedged on both sides of normal to account for this.
National Weather Service also leans warmer for March. The NWS outlook updated two weeks ago also leans warm for the East Coast with no solid inclination on precipitation. They will update their outlook again this evening, and the strong Greenland block may compel them to ease up on the warmth slightly; however, the CFS shown above generally supports their view.