It's a race for the warmest winter on record for Minnesota

Minnesotans are living through the warmest winter of our lifetimes.

It’s been so warm this winter that we’re in a race for the warmest winter ever recorded in Minnesota and the Twin Cities since records began in 1873.

I’ve been crunching our balmy winter temperature numbers so far. We’ve just lived through the warmest December on record in Minnesota. December temperatures were 12.3 degrees warmer than average in the Twin Cities. And December was nearly 16 degrees warmer than average in International Falls on the Canadian border! (15.8 degrees)

I’ve also been looking ahead at the most likely temperatures through the first part of February. The conclusion I reach is that we’re about on pace to challenge the warmest meteorological winter (Dec-Feb) on record of 1877-78.

It’s going to depend on temperatures in February. It will have to be one of the warmest Februarys on record to match 1877-78.

To sanity-check my observations and forecast, I checked in Wednesday with Kenny Blumenfeld at the Minnesota State Climatology Office. His data concurs that we’re in a race for the warmest meteorological winter on record in the Twin Cities and Minnesota.

Here’s his assessment:

Hi Paul, we were just discussing this! For the Twin Cities, where we have records back to 1873, we are currently tracking pretty well with the 1877-78 winter, having been slightly ahead in December (by 0.5 F), and now scrambling to catch its January, which was still 4.7 F ahead through January 23—though we are gaining ground at a clip of 0.4 to 0.6 degrees per day. Assuming forecasts are correct, we will end January somewhere near where the 1877-78 winter was at the same time, setting us up for a February showdown. But February of 1878 was no joke; it was the six-warmest February on record and was 11 degrees above today’s normal. To compete, the coming February will need to have high-ranking warmth. So the 1877-78 winter is not going to roll over for us. It really was extraordinary!

Kenny says robust state numbers are harder to come by for the late 1800s.

It’s a different story for the state-averaged temperature records, but no cakewalk either. In the 1870s, the only stations in Minnesota were Duluth and the Twin Cities, meaning there’s no easy way to get a reliable statewide average from such sparse coverage. The same is true all over the US, so NOAA’s area-averaged dataset starts in 1895, when the era of higher data density began. So we can only compare state-averaged temperatures since 1895. Using that data source, this past December’s warmth has no peers and trounced all other Decembers, beating the previous record-holder (from December 2015) by a head-turning margin of over five degrees F. The previous margin between #1 and #2 had been less than one degree F.

Bottom line? The race for the warmest winter on record is neck and neck. But it will take a remarkably warm February to get there.

From the state-averaged data source, the warmest winter since 1895 is 1997-98. We are ahead of that winter for now, but it boasts the warmest February on record, coming in more than 14 degrees above the current normal, which is how above-normal this past December was. It looks to me like the state will need to be several degrees above normal at least in February to match that winter. So whether we are talking about the Twin Cities or the statewide-average numbers, it will be quite a contest to break the all-time average winter temperature records.

Long winter thaw

I also asked Blumenfeld or his perspective on our supersized January thaw this year.

This will likely end up as one of the longest winter thaws on record for Minnesota. I wondered about how to talk about a January thaw that lasts into February. What’s the record for the longest January thaw that includes adjacent months of December and February?

Hi Paul, I have updated our old thaw story, data, and stats to include ALL thaws back to 1873, including those that began in December or ended in February. The longest is now 21 days, from 2006-07. So I would say the way to discuss this episode is that it is an official January Thaw of course, and its length will be determined by its final date with a high above 32 F, whether that date is in January or February (or, heck, March).

Thanks Kenny, but let’s hope this thaw doesn’t last into March!

2nd longest thaw on record?

Looking at forecast models again today, it looks likely our current thaw will last to at least Feb. 8. Our current thaw in the Twin Cities began on Jan. 22. So if my math (and forecast models) are right, that would make 18 straight days of above-freezing temperatures in the Twin Cities and much of southern Minnesota.

This would tie for the second longest “January thaw” on record.

A shot at 50 degrees?

Forecast models continue to crank out gradually warming temperatures through next week. Highs will gradually rise this week and may approach 40 degrees by this weekend.

Next week looks even warmer. Highs in the 40s look increasingly likely next week.

The European model has been hinting at 50 degrees by the weekend of February 3-4.

Stay tuned.