Props to Punxsutawney Phil and his Feb. 2 prediction.
It was a record-warm February and winter for large portions of the Midwest and the Northeast as repeated mild spells were only briefly interrupted by snaps of cold. Average temperatures over the entire Lower 48 states were the warmest on record during the core winter months.
Snow cover averaged over the nation is at historical lows, and, with new rounds of unseasonably warm weather ahead, spring’s grip is set to strengthen.
Here are four major signs the season is upon us:
1. Leaf-out is surging north into a snowless landscape
The first greenery of spring is popping in the D.C. area and at similar latitudes to the west. It has arrived in northern Kansas, Missouri and the southern Ohio Valley. Parts of the Midwest have seen their first leaf-outs 10 to 14 days earlier than average. Leaf-out also has begun in parts of California’s Central Valley and the Southwest a little ahead of schedule.
The green is emerging while there’s little white to be found. The nation’s snow cover is at its lowest extent on record for March 1. At the same time, ice cover over the Great Lakes is also at historical lows.
2. Over 200 locations had a record-warm winter
More than 200 locations posted their warmest winter on record, often by significant margins; this included more than three dozen weather stations with 75 to 150 years of data.
The following cities all registered their warmest climatological winter, defined as December through February:
- Albany, N.Y. — 33.8 degrees (topping 33.4 degrees in 2015-2016).
- Caribou, Maine — 21.8 degrees (topping 21.6 degrees in 2015-2016).
- Des Moines — 33.1 degrees (topping 32.3 degrees in 1881-1882).
- Fargo, N.D. — 26.5 degrees (topping 22.1 degrees in 2011-2012).
- Fresno, Calif. — 52.9 degrees (topping 52.5 degrees in 2014-2015).
- Green Bay, Wis. — 30.6 degrees (topping 27.7 degrees in 2001-2002).
- International Falls, Minn. — 21.2 degrees (topping 19.6 degrees in 1997-1998)
- Syracuse, N.Y. — 34.2 degrees (topping 34 degrees in 2001-2002).
Many of these same locations also notched their warmest February, as did Chicago; Del Rio, Tex.; Milwaukee; Little Rock; Minneapolis; and Paducah, Ky; among others.
The warmth can be linked to the El Niño climate pattern and the increasing concentration of greenhouse gases in the atmosphere from the burning of fossil fuels.
3. It’s part of a trend and what scientists expect
“Over the long term, we are seeing clear and significant trends toward earlier starts to spring,” Theresa Crimmins, director of the National Phenology Network and associate professor at University of Arizona, said in an email.
A warm winter, especially late winter, sets the stage for a faster onset of spring and early blooms. The average February temperature over the Lower 48 states has increased at a rate of about 0.29 degrees per decade over the past century, or by about 3 degrees overall.
“The primary driver to springtime activity (leaf-out, flowering) is exposure to warmth,” Crimmins said.
But too much winter warmth can also confuse plants. In some cases, a lack of accumulated chill can trick plants into ignoring the growing warmth of spring, delaying their development, Crimmins said.
With winter on the ropes this year, Zachary Labe, a climate scientist at Princeton University, warned that the early green-up could leave early bloomers vulnerable to a destructive freeze event should cold weather make a brief comeback.
4. Forecasts indicate more warmth and sneezing ahead
But there’s little sign the spring progression will slow in the near term as March begins with another wave of unseasonable warmth.
On Friday, a handful of record highs were set from the Dakotas to Michigan, and the number will increase over the weekend throughout the Midwest and the Great Lakes region. While not as many records will fall as did early this week, hundreds are still possible through the middle of next week.
Worsening allergies will tag along with the northward burst of spring as trees unload their pollen.
Medium to high pollen levels have spread into the central Plains, parts of the Ohio Valley and the Mid-Atlantic, according to pollen.com. Portions of the southern United States, including Phoenix, Dallas and Daytona, Fla., are dealing with high pollen levels.
Beyond early next week, longer-range outlooks suggest spring will keep marching north in the eastern half of the nation. However, a brief incursion or two of colder weather is possible through at least mid-March.
Labe cautioned that the exceptional warmth seen around this time both this year and in 2023 isn’t a lock to occur every year into the future, even as the climate keeps warming.
“There is still a lot of variability from year-to-year and place-to-place due to local weather conditions — so some years will occasionally have unusually cold springs,” he said.
