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Abnormally warm weather is toppling records in central and eastern U.S.

An upper-air weather map shows a dome of heat parked over the East Coast. (WeatherBell)

This article, first published Monday evening, has been updated.

Thanksgiving is just around the corner, but the weather feels more like Memorial Day weekend in the central and eastern Lower 48, where highs 15 to 20 degrees above normal have brought about a taste of summer. Even in Michigan and Wisconsin, temperatures have soared well into the 70s.

The mild weather has shattered records in numerous cities and could put some locations on the path to experience their warmest November on record. A brief cool-down is on the way, but signs point to mild weather carrying much of the nation into winter.

On Monday, highs were in the 70s along much of the Eastern Seaboard, approaching the 80-degree mark in spots. The nation’s capital soared to 75 degrees, as did Philadelphia and New York City, where this high temperature set a record for the date. Baltimore lurched to 77 degrees, a degree shy of a record set in 1994. Boston was a bit cooler — in the upper 50s — but could reach the upper 70s on Tuesday afternoon. The National Weather Service reported four dozen new record highs in eastern U.S. alone. Augusta, Ga., Atlantic City, Buffalo, Burlington, Cleveland, Newark, Providence, and Syracuse were among the cities that set records.

D.C.-area forecast: Staying warm for a few more days, but rain returns midweek

The warmth extended into the Upper Midwest, where Chicago set a record high of 75 degrees Monday while Detroit soared to a record high of 77.

In all, the National Weather Service reported 130 locations with temperatures near or above record highs.

High pressure pumps in the heat

The impressive heat comes from a sprawling dome of high pressure centered just off the East Coast. Clockwise flow on the western periphery of the high was deflecting unsettled weather to the north, while also pumping in warm air from the south.

Last week, that mild air mass occupied much of the country, setting record highs in the Intermountain West and High Plains ahead of a cold front.

Highs peaked above 70 degrees all but one day in Minneapolis since Nov. 3, but on Tuesday, the Twin Cities will hover just above freezing.

The same was true in Denver, which had three record highs in a row last week. Saturday, it was 73 degrees; by Monday afternoon, it was snowing.

The surging front has squeezed the heat east, concentrating it from the Midwest and Corn Belt eastward, with highs 15 to 30 degrees above typical values for early to mid-November. On Saturday and Sunday, the Weather Service reported dozens of record high temperatures in the eastern United States. Dozens more came Monday.

The warm spell has set records for its longevity. In Minneapolis; Madison, Wis., and Milwaukee, temperatures reached at least 70 degrees five days in a row, the longest streak ever observed in November. This comes less than three weeks after Minneapolis experienced its largest snowstorm so early in the season.

While the heat will get pushed out of the Midwest in the coming days, it will hang around a bit longer near the East Coast.

Tuesday’s forecast

On Tuesday, the front should stretch from Wisconsin to Kansas City to Oklahoma City, leaving areas ahead of it to enjoy another toasty November day. Chicago could hit 72, a degree above its record from 1949. Indianapolis should reach 75 degrees, flirting with its record high of 76 also set in 1949.

Temperatures in the 80s are possible in the South; a high of 79 or 80 is likely in Houston, Memphis and New Orleans. Upper 80s are possible in Tampa, the latest in what’s been the warmest year to date on record in Tampa, Miami and Orlando.

Washington should hit 74 degrees on Tuesday. In Boston, the forecast will be less fickle than on Monday. Monday’s forecast was “ruined” by a sea breeze that kept the city in the upper 50s most of the day while areas just to the west experienced anomalous warmth; a more southwesterly component of the wind should bring 70s all the way to the coast.

Wednesday’s forecast

On Wednesday, the front will pass through Chicago, knocking temperatures back about 25 degrees into the upper 40s for highs. Indianapolis will likely peak in the mid-50s. Moisture streaming north ahead of Tropical Storm Eta in the Gulf of Mexico will interact with the cold front, bringing moderate to heavy rain along the Eastern Seaboard. Boston, New York, Philadelphia, Baltimore and Washington should still see highs in the 70s.

Springlike warmth set records in the West last week

Rain should linger into Thursday across the Mid-Atlantic and the Northeast, with temperatures dropping late in the week.

In the longer term, however, mild temperatures are likely to stick around across most of the contiguous 48; the National Oceanic and Atmospheric Administration’s Climate Prediction Center highlights above-average odds of unseasonably mild conditions into February.

The intensity and duration of the warm weather over the eastern two-thirds of the nation over the past week is made more likely because of human-caused climate change. NOAA reports more than 3,400 records highs have occurred in that span compared to fewer than 200 record lows.

Jason Samenow contributed to this report.