Temperature difference from normal forecast on Wednesday from NAM model.
All-time February record high temperatures are falling and the air feels more like early May.
Wednesday's average high temperature over the Lower 48 was forecast to soar to a balmy 59 degrees - "the near warmest February day during the last three decades", said Ryan Maue, a meteorologist for WeatherBell Analytics.
A stunning 2,805 record high temperatures have occurred across the nation this month compared with just 27 record lows.
The warmest air with respect to normal has focused on the Midwest and, in some areas, it's unlike anything they've ever witnessed.
Flower stems are sprouting in Chicago, and the Great Lakes are practically ice-free. In an area normally thick with ice, "a boat was seen skimming over the calm waters of Lake Michigan on Monday afternoon," CBS Chicago reported.
Chicago set record highs on four straight days between Friday and Monday, complementing a dizzying number of other warm weather milestones. Before Sunday, when it was 70, it had reached 70 only three other times in records dating to 1871. Then it hit 70 again Monday. And it could hit 70 once more Wednesday.
In other words, half of Chicago's February 70-degree days in recorded history are likely to occur in this one astonishingly warm week.
Chicago's forecast high in the low 70s Wednesday may just fall short of its warmest February temperature on record of 75 from Feb. 27, 1976.
"The NORMAL high in Chicago does not reach 70 degrees until May 15th, which underscores how unusual this warmth truly is," explained WGN's weather blog.
Other Midwestern cities are also basking in the unusual warmth and the highest temperatures are likely still to come.
After setting several daily record highs over the past few days, Madison, Wis., and Milwaukee are both forecast to set their all-time February high temperatures Wednesday.
"Only twice in 130 years in Green Bay have we seen Feb temps reach 60º. The forecast calls for 2 this week," tweeted Jeff Last, a meteorologist at the National Weather Service office in Green Bay.
The record warmth predicted for Wednesday will put an exclamation mark on the warm stretch that began late last week. Here are some more of the notable records that have already been set:
- La Crosse, Wis., tied its all-time February record high of 65 on Sunday.
- Moline, Ill., set its all-time February record high of 74 on Sunday.
- Omaha set daily record highs on Thursday, Friday and Sunday.
- Minneapolis set daily record highs Friday, Saturday, Sunday, and Tuesday.
- St. Cloud, Minn., tied its all-time February record high of 59 Saturday.
- Milwaukee and Detroit just missed, by one degree, tying all-time February record highs Saturday.
- North Platte, Neb. tied its all-time February high of 79 Tuesday
- Scores of daily record highs were set between Wednesday (Feb. 15) and Tuesday from Denver to Philadelphia. Weather.com has a good recap.
Lack of snow and ice
Snow and ice levels are near historic lows thanks to the warm weather.
Snow covered a mere 16.5 percent of the Lower 48 states Tuesday morning, the second lowest amount since the National Oceanic and Atmospheric Administration began keeping records in 2004. Only last year's 16.1 percent, on this date, was lower.
© NOAASnow cover on Feb. 21
This year, few locations outside Maine, northern North Dakota, the Upper Peninsula of Michigan and the Mountain West have appreciable snow cover.
On Wednesday, Chicago will log its 67th straight calendar day without receiving one inch of snow, its longest such snow drought on record.
Meanwhile, the Great Lakes have precious little ice. As of Feb. 20, ice covered just 8.1 percent of the Great Lakes compared with normal coverage of around 42 percent.
Winter to storm back
Wednesday will be the last unusually mild day in the Midwest, until next week at least, as a potent storm winds up over the Plains on Thursday and then races through southeast Minnesota into the Great Lakes by Saturday.
The storm will bring accumulating snow from eastern Wyoming through northwest Wisconsin, where the Weather Service has posted winter storm watches. Depending on the storm's exact track, it could dump up to a foot around Minneapolis.
The storm will drag a strong cold front through much of Midwest so that areas that were in the 60s on Wednesday will only be in the 30s on Saturday.
Comment: The warm temperatures are likely contributing to early blooms by many plants, but a quick reversal to cold temperatures will not be good for those same plants that thought spring was here.