I was amazed that despite the fact we saw some decent sun from the Pike north, the temperatures stayed below freezing. Testament to the cold high pressure system parked overhead. One that keeps us pinned down in below normal temperatures through midweek
It’s a stark contrast to what we saw this time two years ago. This excerpt comes from Michael Rawlins, Asst. Professor at the Department of Geosciences at UMass Amherst:
This time two years ago southern New England experienced one of the most anomalously warm stretches of days since record keeping began in this region in the late 1800s. Over those days locations from Hartford to Boston set high temperature records on several days. A few first-order weather stations recorded daily highs that, when averaged over five days, have no historical analog.
At Amherst, Mass., the daily maximum (high) temperature over the five days of March 18-22, 2012 averaged 30.8 Fahrenheit degrees above the climatological long-term average for those days. This makes that particular five-day anomaly the greatest departure from average over any five-day period during the 130+ year record. Hartford was also 30.8 degrees above the long-term average for those same days, the greatest such departure on record. Boston’s anomaly was 29.0, third all time.
The daily maximum temperature of 83 at Hartford on March 22nd was the warmest it had ever been so early in the year since record keeping began. Previously no temperature greater than 82 (maximum set March 21, 1921) had occurred by that date. The maximum temperature of 82 in Amherst on the 22nd was the warmest it has ever been by that date. Previously no temperature greater than 78 (maximum on three previous dates) had occurred by that date.
Large departures from average, like the ones experienced in March of 2012, and over recent days as well, occur close to the equinoxes when surges of warm air from the south or cold air from the north can easily reach our area.
“For physical reasons related to cloud formation and its cooling effects such large departures from average are highly unlikely during the middle of summer,” [i.e., you won’t see AVG. temps 29-31 degrees above normal in July [[my words]] said Michael Rawlins, manager of the Climate System Research Center and assistant professor of geosciences at Umass Amherst, who compiled the averages.
Few things to take away from this:
- Yes, it can get that warm this time of year.
- The fact that we only had 9.3″ of snow in Boston that season probably gave us a great setup for early-season warmth.
- However, this kind of warmup can’t be explained by normal climate variation.
In this pattern, we’d be lucky to get in the 50s. We’ve had our forays recently, but there isn’t anything long-term that will take hold – and no big shift in the upper air pattern over North America.
Tomorrow, I’ll tell you what may have been behind the deep cold across the continent this winter and what it means for our future seasonal forecasts.
Pete