A blast of bitter cold arctic air brought the coldest temperatures in decades to several Northeast cities Valentine's Day morning. On top of that, wind chills on Sunday dropped into the40sbelow zero in portions of Upstate New York and New England, includingSaranacLake, New York,Pittsfield, Massachusetts, and Montpelier, Vermont.

Record Cold Recap: Temperatures Not Seen in Decades

Northeast Lows Valentine's Day Morning

Actual lows Sunday morning and how long since it's been that cold in each city.

Boston fell to minus 9 degrees Sunday morning, making it the coldest temperature recorded in the city since Jan. 15, 1957, or nearly 60 years. Boston also crushed its Valentine's Day record low of minus 3 degrees set in 1934, and set a daily record low for Feb. 13 (minus 4 degrees) just before midnight on Saturday.The wind chill had fallen as low as minus 36 degrees Sunday morning.

In New York City, the low temperature dipped to a daily record low of 1 degree below zero Sunday morning. This is the coldest reading at Central Park since Jan. 19, 1994, or more than two decades.

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Here are several other cities that have set new daily record lows for Valentine's Day (Feb. 14) and have also seen their coldest temperatures in many years:

Albany, New York: Low of minus 13 degrees beats previous record of minus 10 degrees. Coldest since Jan. 24, 2011.Binghamton, New York: Low of minus 18 degrees crushes previous record of minus 9 degrees. Coldest since Dec. 25, 1980.Hartford, Connecticut (Bradley Airport):Low of minus 12 degrees beats previous record of minus 9 degrees. Coldest since Feb. 5, 1996.Newark, New Jersey: Low of zero degrees ties record low last set in 1979. Coldest since Jan. 16, 2004.Providence, Rhode Island:Low of minus 9 degrees beats previous record of minus 7 degrees. Coldest since Jan. 22, 1984.Syracuse, New York: Low of minus 23 degrees beats previous record of minus 20 degrees set in 1979. Coldest since Jan. 12, 1982.Watertown, New York: Low of minus 37 degrees beat previous record of minus 30 degrees.Worcester, Massachusetts:Low of minus 16 degrees beats previous record of minus 11 degrees. Coldest since Jan. 15, 1957.

The coldest temperature in the Lower 48 on Sunday was reported at Mount Washington, New Hampshire, where the low dropped to minus 40 degrees.

Temperatures remained very cold across the Northeast on Sunday afternoon. Highs were only in the single digits above zero for much of Upstate New York and New England. Highs in the teens stretched from Boston to New York, as well as into the Great Lakes region.

Very cold temperatures gripped the Northeast again Monday morning. Subzero lows were recorded from Connecticut and Rhode Island to Upstate New York and Maine.

Why This Cold Won't Last Long

Now for the good news, if you're already starting to get a little winter fatigue. The bitterly cold air will be very short-lived. Temperatures will already begin to warm up a bit starting Monday, and next weekend should be much less cold.

Above: Forecast surface temperature anomalies (above and below average) from the Friday evening mean of the ECMWF ensemble forecast. Note how the coldest anomalies (pink, purple, blue contours) largely disappear by Tuesday.

The reason for this is another pattern shift in the new week ahead.

ECMWF ensemble mean forecast made at 7 p.m. ET Friday, of Arctic oscillation (blue), Pacific-North American oscillation (light green) and North Atlantic oscillation (red). Note the AO (blue) and PNA (green) flip sign Feb. 15-16, indicative of the pattern change ahead.

(The Weather Company, Professional Division)

Essentially, the large northward bulge of the jet stream bringing record warmth to the West, including California and the Desert Southwest, will flatten a bit. Weather geeks refer to this as a switch from a positive Pacific-North American oscillation to a negative one.

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The corresponding southward plunge of the jet exporting cold air out of Canada into the Midwest and East will then also flatten out next week.

Again, weather geeks would say the Arctic oscillation will switch from negative to positive, meaning the winds around the North Pole will be stronger, keeping the coldest Arctic air bottled up instead of plunging south.

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So, expect a February thaw after this weekend's shivering in parts of the Midwest and East by the latter half of the week.

However, the warm West-chilly East pattern may reestablish itself by the following week. So, enjoy the thaw while you can.

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Jason Souza sweeps the snow from a driveway in New Bedford, Mass., during a snowstorm on Monday, Feb. 8, 2016. The second winter storm in four days to hit the Northeast is expected to bring blizzard conditions to Cape Cod and southeastern Massachusetts and leave behind as much as 18 inches of snow. (Peter Pereira/Standard Times via AP)