Northeast Wisconsin experienced its warmest winter on record
(WFRV) – Last weeks milestone 70-degree day and subsequent drop in temperatures back to below freezing with accumulating snowfall helped solidify meteorological winter of 2023-2024 as a record breaking season in many ways. This serves as a recap of the unseasonably warm and drier winter northeast Wisconsin experienced.
Warmest Winter on Record
To clarify, meteorological winter starts on December 1st through the end of February, however astronomical winter began earlier on the Winter Solstice (Dec. 21-22) through the Vernal Equinox (March 20-21).
In late October, the National Oceanic and Atmospheric Administration forecasted a 40% chance of above average temperatures and a 40% chance of drier then normal conditions, but no one expected to see the historic warmth we experienced this winter. Green Bay recorded is warmest winter on record and by a good margin.
When taking the high and low temperature of all 90 days of this winter and average them together, you get a temperature of 30.6°F, three degrees above the previous warmest winter back in 2001-2002. Digging deeper into the data, the difference between the 2nd and 15th warmest winters on record is also roughly three degrees, going to show how warm this winter was compared to all the rest.
Next, lets break this down by month. December of 2023 was the warmest on record at 34.9°F, breaking the previous record set back in 2015 by a half a degree. Flashback to Christmas Eve and Christmas Day where our highs were 52°F and 54°F respectively, the warmest on record for both days.
Heading into January, we started off fairly mild at a top ten warmest pace and then came our big cold snap on the backside of the seasons major winter storm. Temperatures crashed upwards of 15-25 degrees below average for a week of time, but we then warmed up and still managed to squeak out the 12th warmest winter on record.
Finally onto February and what a month it was to say the least. Wisconsin saw its first tornados recorded in the month of February in Juda and Evansville, WI, but closer to home in the Fox Valley, the weather story was the continued mild temperatures. February of 2024 was the warmest on record at 33.1°F, besting the previous mark by just under two degrees. For reference, this years February average temperatures was warmer then the average March temperature of 32.1°F!
El Nino was a big driver in our unseasonably mild winter on a global scale, but lets take a deeper dive into more of the numbers behind this historic winter. First, of the 90 days this winter, 74 days were recorded over 32°F and doing the math, that’s 82% of the possible days above freezing.
Looking at the graphic below, we saw more 50-degree days this winter then temperatures between 0 and 20 degrees combined and no days with below zero high temperatures. We also saw a staggering 43 days with high temperatures between 30-39 degrees!
Another way to quantify how warm this winter was is by looking at how many days saw above normal temperatures and by how many degrees. Northeast Wisconsin experienced a total of 78 days above average and only 13 days of below average temperatures, resulting in 87% of the possible days in the mild category.
Adding on, we had 26 days with temperatures 10-15 degrees above normal and more days of temperatures 15-20 degrees above then 5-10 above normal; that is how you get some record warmth. On the flip side, our coldest departure from normal was on January 16th, with a temperature departure of 21-degrees below normal.
Snow and Liquid Precipitation
The mild temperatures got much of the talk this winter, but periods of snow did come and it all happened in a very short span of time. We recorded 30.5in of snow this winter, ranking it as the 73rd snowiest winter out of 138 seasons. The average, however, is 32.9in, so we were just barely below it, but you could not tell we recorded that much snow if you looked out your window for many portions of the winter with big chunks of time of bare ground. If the major winter storm in mid January never happened, we would have had a completely different story to tell.
When looking at how much liquid precipitation we saw compared to average, it quantifies as to why portions of northeast Wisconsin are still in some sort of drought. Green Bay tallied 3.63in of liquid precipitation when you combine rain and melting snow. This results in a tie for the 91st wettest out of the possible 138 years of record.
Records Broken
A healthy amount of high temperature records were broken during the winter of 2024. For context, only eight high temperature records were broken in the Spring, Summer and Fall of 2023 combined. We tallied seven records in just winter 2024 alone, a years worth of records in one season!
52° on December 24, 2023
54° on December 25, 2023
46° on February 1, 2024
46° on February 7, 2024
47° on February 12, 2024
54° on February 25, 2024
70° on February 27, 2024
That 70-degree day just last week broke many records, as a handful of northeast Wisconsin communities saw its first 70-degree day in winter and the month of February, the warmest winter day on record and the second largest drop from high to low temperatures as a sharp cold front brought in low temperatures to well below freezing.
Looking Ahead
The Climate Prediction Centers latest forecast is calling for the month of March to likely see above average temperatures as well as slightly drier then normal for precipitation. As a reminder, this does not mean every day will see above average temperatures and have dry conditions. Instead, it means that the average of all the high and low temperatures in March of 2024 will be above the usual average March temperature of 32.1°F and the tally of precipitation will fall slightly below the usual amount of 1.96in.
