A very mild weather pattern by December standards has engulfed a large swath of the Lower 48 states, setting hundreds of record highs and record-warm daily lows. The warmth has been so incredible that several cities in the Midwest and Northeast have set daily record highs during the morning hours this weekend.
According to preliminary data from NOAA’s National Centers for Environmental Information (NCEI), at least 574 record daily highs were tied or broken across the U.S. during the first 10 days of December, representing just under 2 percent of the roughly 30,000 daily high-temperature reports received from more than 3,000 locations. By comparison, just 88 daily record lows were set in the same time frame, all on or before Dec. 5.
That 574-to-88 ratio is likely to become even more imbalanced as additional reports are processed for Friday, Saturday and Sunday, when widespread warmth gripped most of the nation, squeezing out the possibility of record lows over most of the Lower 48.
Temperatures will soar up to 30 degrees above average into Monday, setting even more records. Below are the forecast details and a recap of the records so far.
Cold Air Stays Bottled Up North
Since meteorological winter began Dec. 1, true arctic air has remained locked up in the territories of extreme northern Canada, well to the north of the U.S. border and even well north of all the major Canadian cities.
Current Canada/Northern U.S. Temperatures
While December is early in the winter season, it is quite common for chunks of bitterly cold air to reach the U.S. during the first half of the month – and entirely expected in the Canadian provinces.
However, most of the North American continent has been dominated by air masses of Pacific origin this month, along with occasional intrusions of tropical air from the Gulf of Mexico and the Pacific Ocean off the coast of Mexico.
As a result, temperatures have been consistently above average most of the month across much of the U.S. and Canada.
Although some cooler air has reached the western states, it is what meteorologists call a maritime polar air mass. This air mass is moving in from the northeastern Pacific Ocean and Gulf of Alaska, whose unfrozen waters have added some warmth and moisture to the air, moderating its chilly bite.
Most computer model forecast guidance shows no sign of Arctic air until later this week, when a small chunk of modified Arctic air may briefly visit parts of the north-central U.S. as part of a “December reality check” lowering temperatures in many areas.
December “Spring Fever” Continues
Forecast Highs Compared to Average
High temperatures will remain 10 to 30 degrees above average for many locations in the East through midweek, setting numerous daily record high temperatures.
Some areas are seeing low temperatures that are warmer than their average high temperatures, and a few places may experience some of the mildest low temperatures on record for the month of December. Numerous daily record warm low temperatures will likely fall by the wayside in the eastern two-thirds of the country.
As mentioned earlier, the warmth has been so impressive, that many stations broke daily record high temperatures Saturday morning and again Sunday morning.
Paducah, Kentucky, reached 68 degrees before 1 a.m. Saturday, quickly breaking their record high for the date before peaking at 73 degrees in the afternoon. Other stations that had already reported record highs by 9 a.m. EST Saturday included Cincinnati and Dayton in Ohio. On Sunday morning, New York City, Milwaukee, and Cedar Rapids, Iowa, were among some of the cities that had already set record highs prior to noon. See below for a more complete listing of record highs and record warm lows.
Through Monday morning, temperatures are not expected to drop below the freezing mark for most areas east of the Mississippi River, with the exception of parts of northern New England.
Forecast Low Temperatures
Daily record high temperatures will be threatened in parts of the Midwest and East again Monday on what will likely be the final day of this warm spell’s most intense phase.
However, several record highs are still in jeopardy Tuesday through Thursday as a mild pattern lingers east of the Mississippi River.
Here are the details:
Monday’s Potential Record Highs:
- How many potential records? More than 40 locations among the 236 major weather observation sites in the Lower 48 will threaten daily record highs.
- Which regions will be affected? Some 18 states in an arc from Iowa east to southern New England and south to Florida may see at least one record high.
- Potential Cities (record to beat is in parentheses): Columbia, South Carolina (79 degrees) | Buffalo, New York (64 degrees) | Orlando (86 degrees) | Philadelphia (69 degrees) | Providence, Rhode Island (59 degrees)
Forecast Highs vs. Normal
So, how long will this last?
For the central and southern Plains, a resurgence in above-average temperatures is forecast Monday and Tuesday. Those regions will retreat to near normal Wednesday.
For the Great Lakes region, highs remain above average through Wednesday and should fall back to around average Thursday.
For the East Coast states, expect temperatures well above normal through and including Thursday, with a drop to near normal in most areas Friday. In New England, however, highs may remain 10 or more degrees above normal into Friday.
December Record Highs Broken So Far
Below is a look at the records set so far from this December warmth by day.
Sunday, Dec. 13: Daily record highs were observed in Missouri, Iowa, Illinois, Wisconsin, Michigan, Indiana, Ohio, New York, Pennsylvania, New Jersey, Delaware, Maryland, West Virginia, Virginia, Connecticut, South Carolina, Kentucky, Tennessee, Louisiana, Mississippi, Alabama and Florida.
In New York City, the daily record of 64 at Central Park was tied before 10 a.m. Record highs were also tied or broken before noon in both Madison and Milwaukee, Wisconsin; Youngstown and Toledo, Ohio; and Newark, New Jersey.
Saturday, Dec. 12: Record-breaking warmth reached much of the eastern third of the country, where daily record highs were set at Tupelo, Mississippi (78 degrees), Cape Hatteras, North Carolina (73 degrees), Paducah, Kentucky (73 degrees), Evansville, Indiana (72 degrees), Salisbury, Maryland (72 degrees), Cleveland, Ohio (70 degrees), Indianapolis, Indiana (70 degrees), Fort Wayne, Indiana (69 degrees), Akron, Ohio (68 degrees), Lexington, Kentucky (68 degrees), Trenton, New Jersey (68 degrees), New York City, LaGuardia Airport (66 degrees), New York City, JFK Airport (64 degrees), and Detroit, Michigan (63 degrees).
Dallas-Fort Worth International Airport set a record warm low temperature for the entire month of December at 70 degrees.
Daily record warm low temperatures for Dec. 12 were set in many other locations including New York City (55 degrees), Newark, New Jersey (48 degrees), Louisville, Kentucky (62 degrees), Paducah, Kentucky (65 degrees), and Columbus, Ohio (56 degrees).
Friday, Dec. 11: Unusually warm weather prevailed across much of the central and eastern U.S., where daily record highs were set at San Angelo, Texas (87 degrees), Houston’s Hobby Airport (82 degrees), Wichita Falls, Texas (81 degrees), Shreveport, Louisiana (81 degrees), Mobile, Alabama (78 degrees), Roanoke, Virginia (72 degrees), Rochester, New York (62 degrees) and Sault Ste. Marie, Michigan (47 degrees), among other locations. Record highs were also set in Toronto, Ontario (14 degrees Celsius – 57.2 degrees Fahrenheit) and Ottawa, Ontario (13.5 degrees Celsius – 56.3 degrees Fahrenheit).
Thursday, Dec. 10: More records were broken or tied across the nation’s heartland, including daily record highs at Madison, Wisconsin (56 degrees), and Green Bay, Wisconsin (54 degrees). Rockford, Illinois, hit 57 degrees, tying its record high for the date.
Wednesday, Dec. 9: Record warmth impacted parts of the Plains, where daily record highs included Oklahoma City (74 degrees) and Topeka, Kansas (70 degrees). Minot, North Dakota, hit 62 degrees, tying the daily record and marking its warmest December day since 1939.
Tuesday, Dec. 8: The Northwest saw more record warmth on Tuesday. Seattle-Tacoma Airport set a new daily record high for Dec. 8 of 60 degrees, beating the old record of 59 degrees in 1957. Several other locations in Washington state also set daily record highs, including Spokane, which tied its daily record of 56 degrees. In Oregon, both Portland (62 degrees) and Eugene (62 degrees) set daily record highs Tuesday.
Several daily record highs for Dec. 8 were also set in the Plains Tuesday, including Minot, North Dakota (54 degrees – tie), Lincoln, Nebraska (61 degrees – tie), and Russell, Kansas (67 degrees).
A number of record warm low temperatures were also set for Dec. 8 on Tuesday. Stanley, Idaho, tied its record for any December day with a balmy low of 35. Others included Livingston, Montana (44 degrees), Billings, Montana (43 degrees), Sheridan, Wyoming (36 degrees), Salem, Oregon (59 degrees), and Eugene, Oregon (57 degrees). Eugene beat its old daily record warm low for Dec. 8 by a whopping 10 degrees.
Monday, Dec. 7: Redmond, Oregon, soared to 71 to set a new all-time record high for the month of December. The previous record was 67 on Dec. 1, 2008. Monday’s high also crushed its daily record by a margin of 13 degrees.
Redmond also broke its all-time record-warm daily low for the month of December with a low of 50 Monday, breaking the previous record of 48 set Dec. 10, 2004.
Portland, Oregon, set a new record high of 63 degrees on Monday, as well as a record warm low temperature of 46 degrees. Both of these were recorded at Portland International Airport.
A smattering of record highs also occurred across the northern Rockies and Upper Midwest. Impressively, the Grand Portage Ranger Station in the far northeast corner of Minnesota – with 120 years of weather records in the books – reached 50 degrees, crushing the daily record of 43 and setting an all-time record for its latest 50-degree day on record. The site had only previously reached the 50s on two occasions in December – 51 degrees on Dec. 2, 1962, and 52 degrees two days later.
The appropriately-named town of Max, North Dakota, had its warmest daily low on record for the month of December, only dipping as low as 38. The previous record of 35 had just been set two days earlier; that, in turn, beat the record of 34 from Dec. 29, 1999. Records in Max have been kept for 86 years.
Saturday and Sunday, Dec. 5-6: On Saturday, International Falls tied its record warmest low temperature for the month of December, only dipping to 36 degrees just before midnight. The city set a new daily record high of 45 degrees on Sunday.
The cooperative observer near Ladysmith, Wisconsin, reported a high of 46 Sunday – crushing the daily record of 40 in an impressive 114-year period of recordkeeping.
An additional fourteen daily record highs were set in Manitoba Saturday and Sunday, including Emerson (7.1 degrees Celsius/44.8 degrees Fahrenheit on Sunday) where records date back to 1877.
In Oregon, Redmond hit 63 and Roseburg hit 61, both daily record highs for Saturday. Redmond hit 63 again Sunday, setting another daily record.
Friday, Dec. 4: At least 16 Canadian cities set daily record highs, particularly in Manitoba, where the city of Morden, southwest of Winnipeg, soared to 14.2 degrees Celsius (about 57.6 degrees Fahrenheit).
Highs reached the freezing mark as far north as Thompson, Manitoba on Friday (roughly 55 degrees North latitude, about 470 miles north of Winnipeg). The average high on December 4 there is -13.8 C (7.1 F). Just a bit farther northeast of there on Saturday, Gillam, Manitoba, reached the freezing mark which also was a new daily record (0.3 C / 32.5 F).
In the U.S., both Marquette, Michigan (50 degrees at the NWS office in nearby Negaunee Township), and International Falls, Minnesota (45 degrees), tied their daily record highs Friday.
Thursday, Dec. 3: Only a few record highs were set at places with long-term records. Three were in Florida, including 85 at Fort Lauderdale Beach; one was in Washington, where Bellingham hit 62.
Wednesday, Dec. 2: Charleston, South Carolina, and Wilmington, North Carolina, each hit 80 degrees to break daily record highs. On the opposite side of the country, a high of 60 was good for a daily record in Bellingham, Washington.
Tuesday, Dec. 1: A handful of locations in Florida and south Alabama set daily records, including a high of 89 near Avon Park, Florida, where records have been kept for 121 years.
What Effects Will This Warmth Have?
As a result of the jet stream staying north of the U.S. frequently throughout November, parts of the Northeast and Mid-Atlantic have remained rather mild and snowless recently. Philadelphia saw its second warmest November on record in 2015, and made it through the autumn to the start of December without a freeze for the first time since 1939.
For Buffalo, New York, it was the seventh warmest November on record. Buffalo has also yet to see accumulating snowfall this season, marking the longest the city has gone in a snow season without receiving its first measurable snow.
The lack of snowfall and nights below 32 degrees means a tough start for ski resorts in parts of New England and the Appalachians. Over the Great Lakes, on the heels of record late-season ice into spring 2015, lake ice formation may be significantly delayed.
Interestingly enough, a delay in freezing of the lakes could support a later lake-effect snow season, as colder air moving over warmer lake water can lead to the development of heavy snow bands into early winter. This, however, depends on the ability of substantial moisture to coincide with sufficient cold air, something that has struggled to happen so far this season.
It is not just the northeastern quarter of the country that has escaped the bulk of winter’s fury to date.
Florida, in particular, has been on quite a stretch for above normal temperatures. In November, Naples and Fort Lauderdale recorded their warmest November on record. For Miami and West Palm Beach, it was their second warmest November on record.
Fargo, North Dakota has reached 40 degrees or higher on 260 days so far in 2015. Dating back to 1942, the record is 261 days in 2012, but December 2015 could push them over the edge before the month is over.
What About Last Winter?
December 2014 was also a warmer than average month for much of the country. Despite that happening, winter took a fast turnaround in parts of the Northeast.
The pattern changed very quickly in the winter of 2014-15 with record-setting snows hitting parts of New England in January in February.
There are some differences between this winter and last winter, particularly with the strong El Nino currently in place.
Regardless, weather patterns are bound to change at some point, so check back regularly with weather.com for the latest information.