bluewave

At least we were able to avoid the immediate near to over 50°warm up following our 5”+ events in recent years for the best snowfall retention since 2021. Data for ISLIP-LI MACARTHUR AP, NY Click column heading to sort ascending, click again to sort descending. 2026-01-25 29 12 1.13 12.9 T 2026-01-26 26 17 0.03 0.3 9 2026-01-27 21 14 0.00 0.0 8 2026-01-28 23 10 0.00 0.0 8 2026-01-29 22 10 0.00 0.0 8 2026-01-30 17 8 0.00 0.0 8 2026-01-31 21 0 0.00 0.0 8 2026-02-01 20 12 T T 8 2026-02-02 32 15 0.00 0.0 8 Data for ISLIP-LI MACARTHUR AP, NY Click column heading to sort ascending, click again to sort descending. 2025-12-14 34 22 0.39 5.8 2 2025-12-15 29 19 0.00 0.0 6 2025-12-16 34 25 0.00 0.0 4 2025-12-17 46 24 0.00 0.0 2 2025-12-18 51 27 T 0.0 T 2025-12-19 59 34 0.68 0.0 0 2025-12-20 42 28 0.00 0.0 0 2025-12-21 50 30 0.00 0.0 0 Data for ISLIP-LI MACARTHUR AP, NY Click column heading to sort ascending, click again to sort descending. 2025-12-26 29 21 0.70 5.6 0 2025-12-27 31 22 0.13 1.0 5 2025-12-28 42 16 0.04 0.0 4 2025-12-29 49 32 0.22 0.0 1 2025-12-30 34 28 0.00 0.0 0 2025-12-31 36 28 T 0.1 0 Data for ISLIP-LI MACARTHUR AP, NY Click column heading to sort ascending, click again to sort descending. 2025-02-08 36 23 0.52 4.0 0 2025-02-09 36 27 0.17 T 4 2025-02-10 36 23 0.00 0.0 2 2025-02-11 33 19 0.16 1.4 1 2025-02-12 36 32 0.14 0.5 3 2025-02-13 45 35 0.25 0.0 1 2025-02-14 38 28 0.00 0.0 0 2025-02-15 37 24 0.39 0.5 0 2025-02-16 53 37 1.41 0.0 0 Data for ISLIP-LI MACARTHUR AP, NY Click column heading to sort ascending, click again to sort descending. 2022-01-28 35 26 0.09 1.2 0 2022-01-29 29 14 1.24 23.5 10 2022-01-30 24 6 0.00 0.0 24 2022-01-31 32 6 0.00 0.0 22 2022-02-01 36 11 0.00 0.0 20 2022-02-02 46 26 0.00 0.0 17 2022-02-03 49 37 0.11 0.0 12 2022-02-04 51 27 0.69 0.2 5 2022-02-05 29 19 T T 1 2022-02-06 29 14 0.00 0.0 0 Data for ISLIP-LI MACARTHUR AP, NY Click column heading to sort ascending, click again to sort descending. 2021-02-01 34 27 0.69 10.3 3 2021-02-02 36 30 0.07 0.3 11 2021-02-03 35 28 0.03 0.4 10 2021-02-04 40 25 0.00 0.0 10 2021-02-05 44 27 0.03 0.0 9 2021-02-06 43 27 0.00 0.0 7 2021-02-07 37 26 0.29 6.4 5 2021-02-08 29 13 0.00 0.0 11 2021-02-09 37 13 0.01 0.0 9 2021-02-10 33 21 T T 8 2021-02-11 31 25 0.17 1.8 10 2021-02-12 29 18 0.00 0.0 9 2021-02-13 30 25 T T 9 2021-02-14 36 29 T T 8 2021-02-15 35 32 0.01 T 7 Data for ISLIP-LI MACARTHUR AP, NY Click column heading to sort ascending, click again to sort descending. 2020-12-16 33 24 0.36 5.7 0 2020-12-17 35 24 0.64 1.7 3 2020-12-18 30 23 0.00 0.0 5 2020-12-19 34 19 0.00 0.0 4 2020-12-20 35 24 0.06 0.1 3 2020-12-21 44 33 0.00 0.0 3 2020-12-22 45 35 T 0.0 2 2020-12-23 45 27 0.00 0.0 1 2020-12-24 59 41 0.02 0.0 T 2020-12-25 59 32 1.05 0.0 0

Yeah, this has been the first time since 17-18 and 10-11 that Islip averaged under 35.0° for both December and January. Monthly Mean Avg Temperature for ISLIP-LI MACARTHUR AP, NY Click column heading to sort ascending, click again to sort descending. 2025-2026 34.3 29.6 32.0 2024-2025 36.5 30.4 33.5 2023-2024 42.2 35.1 38.7 2022-2023 36.8 41.1 39.0 2021-2022 41.7 28.8 35.3 2020-2021 37.2 32.9 35.1 2019-2020 36.8 37.3 37.1 2018-2019 38.1 31.1 34.6 2017-2018 33.8 30.1 32.0 2016-2017 36.6 36.2 36.4 2015-2016 48.4 33.3 40.8 2014-2015 39.6 28.7 34.2 2013-2014 37.1 27.7 32.4 2012-2013 40.5 33.1 36.8 2011-2012 40.5 36.2 38.4 2010-2011 31.5 27.1 29.3 2009-2010 34.5 30.4 32.5 2008-2009 36.7 26.5 31.6 2007-2008 35.1 33.8 34.5 2006-2007 41.1 35.9 38.5 2005-2006 33.5 37.5 35.5 2004-2005 35.2 28.5 31.9 2003-2004 36.6 23.5 30.1 2002-2003 33.5 26.5 30.0 2001-2002 41.2 37.7 39.5 2000-2001 29.6 29.5 29.6 1999-2000 38.3 29.5 33.9 1998-1999 40.0 33.7 36.9 1997-1998 37.7 39.1 38.4 1996-1997 39.0 30.2 34.6 1995-1996 31.4 30.4 30.9 1994-1995 39.7 38.0 38.9 1993-1994 35.2 25.6 30.4 1992-1993 36.1 34.6 35.4 1991-1992 37.3 32.5 34.9 1990-1991 39.9 32.1 36.0 1989-1990 24.8 37.9 31.4 1988-1989 33.4 34.6 34.0 1987-1988 36.8 26.6 31.7 1986-1987 36.4 30.5 33.5 1985-1986 32.1 31.7 31.9 1984-1985 41.2 26.2 33.7 1983-1984 33.6 27.3 30.5 1982-1983 40.1 32.7 36.4 1981-1982 36.1 25.8 31.0 1980-1981 33.5 25.2 29.4 1979-1980 39.1 32.3 35.7 1978-1979 36.9 31.7 34.3 1977-1978 32.8 25.5 29.2 1976-1977 28.9 20.8 24.9 1975-1976 35.2 26.5 30.9 1974-1975 36.9 35.0 36.0 1973-1974 38.4 32.8 35.6 1972-1973 39.6 32.7 36.2 1971-1972 40.1 33.7 36.9 1970-1971 34.0 27.1 30.6 1969-1970 33.4 23.3 28.4 1968-1969 29.3 30.1 29.7 1967-1968 33.1 23.8 28.5 1966-1967 33.0 33.8 33.4 1965-1966 36.0 29.5 32.8 1964-1965 35.5 25.5 30.5 1963-1964 28.1 32.3 30.2

This has been a top 30 coldest 10 day period on Long Island and the coldest since 2017. Minimum 10-Day Mean Avg Temperature for ISLIP-LI MACARTHUR AP, NY Click column heading to sort ascending, click again to sort descending. 1 8.3 1979-02-09 through 1979-02-18 0 2 8.6 1979-02-10 through 1979-02-19 0 3 9.9 1979-02-11 through 1979-02-20 0 4 10.0 1979-02-08 through 1979-02-17 0 5 11.3 1979-02-07 through 1979-02-16 0 6 11.9 1979-02-06 through 1979-02-15 0 7 12.5 1968-01-04 through 1968-01-13 0 8 12.7 1979-02-12 through 1979-02-21 0 9 12.8 1979-02-05 through 1979-02-14 0 10 13.0 1968-01-02 through 1968-01-11 0 11 13.2 1968-01-03 through 1968-01-12 0 12 13.5 1968-01-05 through 1968-01-14 0 13 14.0 1968-01-01 through 1968-01-10 0 14 15.0 1979-02-04 through 1979-02-13 0 15 15.2 1968-01-06 through 1968-01-15 0 16 15.5 1967-12-31 through 1968-01-09 0 17 15.6 2017-12-29 through 2018-01-07 0 - 15.6 1981-01-04 through 1981-01-13 0 18 15.7 1968-01-07 through 1968-01-16 0 19 16.0 2017-12-28 through 2018-01-06 0 - 16.0 1981-01-03 through 1981-01-12 0 - 16.0 1968-01-08 through 1968-01-17 0 20 16.2 1965-01-11 through 1965-01-20 0 21 16.3 1979-02-13 through 1979-02-22 0 22 16.4 1982-01-10 through 1982-01-19 0 23 16.4 1981-01-05 through 1981-01-14 0 24 16.5 1977-01-12 through 1977-01-21 0 25 16.5 1977-01-15 through 1977-01-24 0 26 16.6 2017-12-30 through 2018-01-08 0 - 16.6 1977-01-13 through 1977-01-22 0 - 16.6 1977-01-11 through 1977-01-20 0 27 16.8 2026-01-24 through 2026-02-02 0

It was the only time Central NJ finished a season with 80.8°of snow and Newark couldn’t make it to 50”. Snowfall Data for October 1, 2009 through April 30, 2010 Click column heading to sort ascending, click again to sort descending. WRIGHTSTOWN COOP 80.8 HAMMONTON 3.3 WSW CoCoRaHS 79.6 FRANKLIN TWP 2.7 W CoCoRaHS 79.0 TOMS RIVER COOP 76.0 JEFFERSON TWP 2.4 ENE CoCoRaHS 75.3 BUENA VISTA TWP 2.6 NNE CoCoRaHS 75.2 BETHLEHEM TWP 0.6 S CoCoRaHS 74.3 SPARTA TWP 3.7 E CoCoRaHS 74.3 HAMILTON TWP 2.1 SE CoCoRaHS 74.1 HAMMONTON 1 NE COOP 71.2 INDIAN MILLS 2 W COOP 70.0 PHILADELPHIA/MT. HOLLY WFO COOP 69.7 ESTELL MANOR COOP 68.6 MOORESTOWN TWP 0.6 SE CoCoRaHS 68.0 HOWELL TWP 2.5 W CoCoRaHS 67.6 HOLLAND TWP 2.6 NNE CoCoRaHS 67.2 HARDYSTON TWP 3.2 SE CoCoRaHS 67.1 VINELAND 3.5 NW CoCoRaHS 66.8 SOMERDALE 4 SW COOP 63.5 POINT PLEASANT BEACH 0.5 SW CoCoRaHS 62.9 BERKELEY TWP 2.9 ENE CoCoRaHS 61.2 OAKLAND 0.9 SSE CoCoRaHS 60.0 ROCKAWAY 0.4 NNW CoCoRaHS 59.3 WOODBINE 5.1 NE CoCoRaHS 59.0 BLAIRSTOWN TWP 2.0 SE CoCoRaHS 58.2 RANDOLPH TWP 0.8 W CoCoRaHS 58.2 ATLANTIC CITY INTL AP WBAN 58.1 Atlantic City Area ThreadEx 58.1 GREENWICH TWP 1.6 S CoCoRaHS 58.1 ROCKAWAY TWP 0.7 NE CoCoRaHS 57.6 LACEY TWP 6.3 E CoCoRaHS 57.6 ESTELL MANOR 4.0 WNW CoCoRaHS 57.5 RED BANK 1.3 NW CoCoRaHS 57.5 MANASQUAN 1 NW COOP 57.2 LINWOOD 0.7 SSW CoCoRaHS 57.1 VERNON TWP 1.7 N CoCoRaHS 56.8 LAWRENCE TWP 1.0 NNW CoCoRaHS 56.3 TENAFLY 1.3 W CoCoRaHS 55.7 PENNSAUKEN 1N COOP 55.0 MOUNT OLIVE TWP 2.1 WNW CoCoRaHS 55.0 CAPE MAY 2 NW COOP 54.2 BRICK TWP 1.5 NNE CoCoRaHS 54.0 FLEMINGTON 5 NNW COOP 53.9 CLINTON TWP 3.9 N CoCoRaHS 53.9 TRENTON-MERCER AIRPORT WBAN 53.6 Trenton Area ThreadEx 53.6 CALIFON 0.6 NW CoCoRaHS 53.5 LEBANON 2.8 N CoCoRaHS 53.3 WASHINGTON 0.6 ENE CoCoRaHS 53.0 LIBERTY TWP 1.7 WSW CoCoRaHS 52.7 ROBBINSVILLE TWP 1.7 WSW CoCoRaHS 52.7 VERNON TWP 2.4 WSW CoCoRaHS 52.3 UPPER DEERFIELD TWP 1.7 SW CoCoRaHS 51.8 HILLSBOROUGH TWP 4.7 ESE CoCoRaHS 51.7 KNOWLTON TWP 3.2 SSE CoCoRaHS 51.6 NEW BRUNSWICK 3 SE COOP 51.5 New Brunswick Area ThreadEx 51.5 FRANKLIN TWP 2.8 NNE CoCoRaHS 51.2 HAMILTON TWP 2.3 NE CoCoRaHS 51.0 RAMSEY 0.6 E CoCoRaHS 50.4 HIGH BRIDGE 0.6 WNW CoCoRaHS 50.3 LONG HILL TWP 1.8 WSW CoCoRaHS 50.1 WANTAGE TWP 1.5 SE CoCoRaHS 49.8 SUSSEX 1 NW COOP 49.7 FREEHOLD-MARLBORO COOP 49.4 CHATHAM 2 W COOP 49.4 BRIDGEWATER TWP 3.3 NW CoCoRaHS 49.3 NORTH BRUNSWICK TWP 1.5 W CoCoRaHS 49.1 SADDLE BROOK TWP 0.6 E CoCoRaHS 48.8 HACKETTSTOWN 0.8 W CoCoRaHS 48.6 Newark Area ThreadEx 47.9 NEWARK LIBERTY INTL AP WBAN 47.9

The old forecasters rule was that if the models started showing a major snowstorm in Philly it would keep coming north into our area right up until storm time. This was the case in 1983, 1996, and 2016 when the forecasts started out showing the heaviest snows staying to the south of our area. 2-6-10 was the one exception in modern times. It was the first time in recorded history that Newark recorded less than 1” of snow with 20”+ in Philly. Let’s hope we never see a snowfall cutoff like that ever again. Snowstorms over 20” in Philly vs Newark 1-9-1996…….PHL…31.0”….EWR….27.8” 2-7-2010……..PHL…28.5”…EWR….0.4” 12-21-2009….PHL….23.2”…EWR….11.2” 1-24-2016……PHL….22.4”…EWR….24.2” 2-13-1983……PHL….21.9”….EWR….16.1” 12-27-1909….PHL…..21.0”…EWR….7.5” 2-17-2003…..PHL…..20.7”…EWR….23.1”

Unfortunately, 2-5-10 was one of our worst cases of suppression as the record snows went just to our south.

Very impressive Arctic outbreak possible next weekend as a lobe of the polar vortex is forecast to dive into the Northeast. Places like NYC have a chance to drop lower than this weekend since the winds look to be stronger with more of NW flow and stronger high pressure to the west. Instead of the light winds like we had this weekend which didn’t transport the coldest air into the heat island. My guess is that we will finally get a thaw beginning a few days later as the entire polar vortex shifts back closer to the Arctic and Asia.

We finally got the Southern Stream to become active over the last 7 days. So it delivered our first KU Benchmark storm since 2022 with widespread 10”+ amounts across the Northeast. The benchmark track which is a prerequisite allowed several stations to finally have a 25” season before we even reached February. But since the Western ridge has been so overpowering this winter, the big storm last weekend occurred with a deep trough out West and a transient Southeast ridge. So we needed a relaxation of the ridge for our big storm. One of the December clippers also occurred with a trough out West and a transient Southeast ridge. But that event was Northern Stream dominant so there weren’t widespread 10”+ amounts since the Atlantic and Gulf moisture couldn’t get tapped. The ridge and trough axis was too far east today for the big ocean storm to come closer to the coast. So the Western ridge was just a little too overpowering this weekend. Same theme for much of the winter outside one of our December clippers and the big storm last weekend. The other thing is that getting two 10” events only 7 days apart has only happened once in our area since the 1990s. This was the rare twin 10”+ snowstorms only a few days apart in February 1994. Even during the phenomenal 2010-2018 snowfall run we needed at least several weeks to reload the 10”+ snowfall pattern. The best run from this period was the 60”+ in 33 days from December 2010 into January 2011. But the storms were spaced out at longer than 7 day intervals. Overpowering Western ridge relaxed for the clipper and benchmark storms Late January benchmark track Ridge and trough axis today just a little too far east

Here is another example of how in the past we often had coast to coast cold at durations lasting a month to occasionally the entire DJF winter season. December 2025 was the 39th coldest in the Northeast and the same average temperature of 24.2° as 2017 was. But this is the first time an average Northeast December temperature in this range occurred with all-time warmth in the West near +15° above the long term averages. Back in 2017 we did have some warmth in the Southwest but nothing as extreme as this December was. The other years with that were within about 0.6°which the Northeast was this December had the cold extending to the West Coast. So we can see the warmth expanding out of the Southwest over time and increasing in coverage and magnitude.

That is just one example. The total amount across many locations and timeframes is too vast for me to list in one thread. But I have plenty of more examples for other individual locations and time periods.

This January was much warmer in the Arctic and the CONUS than 1977.

2019 was the warmest January at Rockford, IL to feature a -25° or colder reading with the big temperature swings that month and a high over 50°. Climatological Data for Rockford Area, IL (ThreadEx) - January 2019 Click column heading to sort ascending, click again to sort descending. Sum 788 333 - - 1449 0 2.27 24.9 - Average 25.4 10.7 18.1 -3.7 - - - - 5.9 Normal 29.1 14.5 21.8 - 2019-01-01 32 23 27.5 4.2 37 0 T T 0 2019-01-02 28 22 25.0 1.9 40 0 T T 0 2019-01-03 39 20 29.5 6.5 35 0 0.00 0.0 0 2019-01-04 46 26 36.0 13.2 29 0 0.00 0.0 0 2019-01-05 50 26 38.0 15.3 27 0 0.00 0.0 0 2019-01-06 40 26 33.0 10.5 32 0 T 0.0 0 2019-01-07 51 37 44.0 21.6 21 0 0.53 0.0 0 2019-01-08 44 21 32.5 10.3 32 0 0.00 0.0 0 2019-01-09 23 16 19.5 -2.6 45 0 T T 0 2019-01-10 27 14 20.5 -1.5 44 0 0.00 0.0 0 2019-01-11 29 17 23.0 1.2 42 0 0.00 0.0 0 2019-01-12 31 29 30.0 8.3 35 0 0.28 3.8 0 2019-01-13 32 26 29.0 7.4 36 0 0.01 0.2 4 2019-01-14 26 23 24.5 3.0 40 0 0.00 0.0 4 2019-01-15 33 24 28.5 7.0 36 0 T T 4 2019-01-16 34 26 30.0 8.6 35 0 T 0.0 3 2019-01-17 33 27 30.0 8.7 35 0 T T 3 2019-01-18 30 23 26.5 5.2 38 0 0.17 2.3 2 2019-01-19 24 6 15.0 -6.2 50 0 0.13 4.0 8 2019-01-20 10 -2 4.0 -17.2 61 0 0.00 0.0 8 2019-01-21 14 -7 3.5 -17.7 61 0 0.00 0.0 8 2019-01-22 31 13 22.0 0.8 43 0 0.24 1.5 7 2019-01-23 29 9 19.0 -2.2 46 0 0.23 4.2 11 2019-01-24 22 -2 10.0 -11.2 55 0 T 0.2 13 2019-01-25 1 -11 -5.0 -26.3 70 0 0.05 0.6 12 2019-01-26 5 -21 -8.0 -29.3 73 0 0.07 1.5 14 2019-01-27 8 -15 -3.5 -24.9 68 0 0.10 1.3 14 2019-01-28 21 9 15.0 -6.5 50 0 0.38 4.0 17 2019-01-29 10 -16 -3.0 -24.6 68 0 T 0.2 17 2019-01-30 -13 -25 -19.0 -40.7 84 0 0.00 0.0 17 2019-01-31 -2 -31 -16.5 -38.3 81 0 0.08 1.1 16 Climatological Data for Rockford Area, IL (ThreadEx) - January 1982 Click column heading to sort ascending, click again to sort descending. Sum 594 -47 - - 1735 0 1.58 14.8 - Average 19.2 -1.5 8.8 -13.0 - - - - 6.0 Normal 29.1 14.5 21.8 - 1982-01-01 18 3 10.5 -12.8 54 0 0.00 0.0 3 1982-01-02 34 15 24.5 1.4 40 0 0.28 1.9 3 1982-01-03 34 20 27.0 4.0 38 0 0.18 0.3 4 1982-01-04 33 9 21.0 -1.8 44 0 0.16 1.3 4 1982-01-05 31 6 18.5 -4.2 46 0 0.00 0.0 4 1982-01-06 23 5 14.0 -8.5 51 0 0.08 1.1 4 1982-01-07 5 -10 -2.5 -24.9 67 0 0.00 0.0 5 1982-01-08 15 -10 2.5 -19.7 62 0 0.02 0.3 5 1982-01-09 5 -21 -8.0 -30.1 73 0 0.04 0.4 5 1982-01-10 -5 -27 -16.0 -38.0 81 0 0.00 0.0 5 1982-01-11 3 -6 -1.5 -23.3 66 0 0.00 0.0 5 1982-01-12 10 -8 1.0 -20.7 64 0 0.11 1.1 5 1982-01-13 16 -3 6.5 -15.1 58 0 0.07 0.9 6 1982-01-14 7 -15 -4.0 -25.5 69 0 0.00 0.1 6 1982-01-15 12 -18 -3.0 -24.5 68 0 0.04 0.6 6 1982-01-16 6 -24 -9.0 -30.4 74 0 0.00 0.0 6 1982-01-17 2 -25 -11.5 -32.8 76 0 0.11 2.1 6 1982-01-18 22 0 11.0 -10.3 54 0 0.00 0.0 8 1982-01-19 27 5 16.0 -5.2 49 0 0.00 0.0 7 1982-01-20 28 7 17.5 -3.7 47 0 0.09 0.7 7 1982-01-21 27 23 25.0 3.8 40 0 0.00 0.0 8 1982-01-22 37 18 27.5 6.3 37 0 0.16 0.3 7 1982-01-23 37 -1 18.0 -3.2 47 0 0.00 0.0 7 1982-01-24 -1 -9 -5.0 -26.2 70 0 0.02 0.3 7 1982-01-25 7 -9 -1.0 -22.3 66 0 0.08 2.1 9 1982-01-26 9 -18 -4.5 -25.8 69 0 0.00 0.0 9 1982-01-27 35 8 21.5 0.1 43 0 0.00 0.0 9 1982-01-28 34 6 20.0 -1.5 45 0 0.00 0.0 7 1982-01-29 32 6 19.0 -2.6 46 0 0.13 1.1 6 1982-01-30 31 18 24.5 2.8 40 0 0.00 0.0 7 1982-01-31 20 8 14.0 -7.8 51 0 0.01 0.2 6 Climatological Data for Rockford Area, IL (ThreadEx) - January 1985 Click column heading to sort ascending, click again to sort descending. Sum 712 87 - - 1607 0 1.00 13.4 - Average 23.0 2.8 12.9 -8.9 - - - - 8.6 Normal 29.1 14.5 21.8 - 1985-01-01 31 2 16.5 -6.8 48 0 0.34 3.9 9 1985-01-02 10 -8 1.0 -22.1 64 0 0.00 0.0 9 1985-01-03 19 -14 2.5 -20.5 62 0 0.00 0.0 9 1985-01-04 32 -8 12.0 -10.8 53 0 0.00 0.0 9 1985-01-05 39 24 31.5 8.8 33 0 0.00 0.0 8 1985-01-06 37 24 30.5 8.0 34 0 0.00 0.0 7 1985-01-07 37 28 32.5 10.1 32 0 T T 7 1985-01-08 28 8 18.0 -4.2 47 0 T T 7 1985-01-09 22 8 15.0 -7.1 50 0 0.01 0.1 7 1985-01-10 24 15 19.5 -2.5 45 0 0.11 1.7 8 1985-01-11 20 4 12.0 -9.8 53 0 T T 8 1985-01-12 14 0 7.0 -14.7 58 0 0.00 0.0 8 1985-01-13 28 9 18.5 -3.1 46 0 0.00 0.0 8 1985-01-14 35 4 19.5 -2.0 45 0 0.01 0.3 8 1985-01-15 15 -8 3.5 -18.0 61 0 0.00 0.0 8 1985-01-16 22 11 16.5 -4.9 48 0 0.15 2.2 8 1985-01-17 22 11 16.5 -4.8 48 0 0.14 1.9 10 1985-01-18 25 6 15.5 -5.8 49 0 0.02 0.4 11 1985-01-19 6 -24 -9.0 -30.2 74 0 T T 11 1985-01-20 -5 -26 -15.5 -36.7 80 0 T T 11 1985-01-21 17 -6 5.5 -15.7 59 0 T T 11 1985-01-22 22 12 17.0 -4.2 48 0 T T 10 1985-01-23 27 15 21.0 -0.2 44 0 T T 8 1985-01-24 30 21 25.5 4.3 39 0 0.06 0.9 8 1985-01-25 29 -5 12.0 -9.3 53 0 0.01 0.2 9 1985-01-26 22 -10 6.0 -15.3 59 0 0.00 0.0 9 1985-01-27 30 8 19.0 -2.4 46 0 0.00 0.0 8 1985-01-28 15 -5 5.0 -16.5 60 0 0.00 0.0 8 1985-01-29 22 -6 8.0 -13.6 57 0 0.01 0.2 8 1985-01-30 28 9 18.5 -3.2 46 0 0.14 1.5 7 1985-01-31 9 -12 -1.5 -23.3 66 0 T 0.1 9 Climatological Data for Rockford Area, IL (ThreadEx) - January 2009 Click column heading to sort ascending, click again to sort descending. Sum 695 160 - - 1580 0 0.81 12.6 - Average 22.4 5.2 13.8 -8.0 - - - - 5.1 Normal 29.1 14.5 21.8 - 2009-01-01 31 16 23.5 0.2 41 0 0.00 0.0 1 2009-01-02 30 14 22.0 -1.1 43 0 0.00 0.0 T 2009-01-03 37 16 26.5 3.5 38 0 T 0.0 T 2009-01-04 37 14 25.5 2.7 39 0 0.26 0.0 T 2009-01-05 29 9 19.0 -3.7 46 0 0.00 0.0 T 2009-01-06 31 17 24.0 1.5 41 0 0.06 0.8 T 2009-01-07 28 12 20.0 -2.4 45 0 T 0.2 1 2009-01-08 23 9 16.0 -6.2 49 0 T T 1 2009-01-09 30 12 21.0 -1.1 44 0 0.24 2.7 3 2009-01-10 28 18 23.0 1.0 42 0 0.04 3.8 6 2009-01-11 19 8 13.5 -8.3 51 0 T T 7 2009-01-12 27 7 17.0 -4.7 48 0 0.05 1.7 7 2009-01-13 22 -5 8.5 -13.1 56 0 0.01 0.4 7 2009-01-14 9 -6 1.5 -20.0 63 0 0.12 1.9 8 2009-01-15 -6 -17 -11.5 -33.0 76 0 0.00 0.0 9 2009-01-16 0 -25 -12.5 -33.9 77 0 0.00 0.0 9 2009-01-17 27 0 13.5 -7.8 51 0 T T 8 2009-01-18 17 9 13.0 -8.3 52 0 T 0.1 8 2009-01-19 20 6 13.0 -8.2 52 0 0.02 0.4 8 2009-01-20 19 6 12.5 -8.7 52 0 0.00 0.0 7 2009-01-21 25 10 17.5 -3.7 47 0 0.00 0.0 7 2009-01-22 31 5 18.0 -3.2 47 0 0.00 0.0 7 2009-01-23 27 12 19.5 -1.7 45 0 0.00 0.0 6 2009-01-24 12 -5 3.5 -17.7 61 0 0.00 0.0 6 2009-01-25 11 -5 3.0 -18.3 62 0 0.00 0.0 6 2009-01-26 14 -4 5.0 -16.3 60 0 T T 6 2009-01-27 15 4 9.5 -11.9 55 0 0.01 0.2 6 2009-01-28 16 1 8.5 -13.0 56 0 T 0.3 6 2009-01-29 29 15 22.0 0.4 43 0 T 0.1 6 2009-01-30 16 0 8.0 -13.7 57 0 T T 6 2009-01-31 41 7 24.0 2.2 41 0 0.00 0.0 6 Climatological Data for Rockford Area, IL (ThreadEx) - January 1924 Click column heading to sort ascending, click again to sort descending. Sum 792 90 - - 1566 0 1.27 9.5 - Average 25.5 2.9 14.2 -7.6 - - - - 3.8 Normal 29.1 14.5 21.8 - 1924-01-01 19 -13 3.0 -20.3 62 0 0.00 0.0 5 1924-01-02 24 -4 10.0 -13.1 55 0 T T 5 1924-01-03 21 -6 7.5 -15.5 57 0 0.00 0.0 5 1924-01-04 12 -11 0.5 -22.3 64 0 T T 5 1924-01-05 -11 -25 -18.0 -40.7 83 0 0.00 0.0 5 1924-01-06 23 -19 2.0 -20.5 63 0 0.00 0.0 5 1924-01-07 32 7 19.5 -2.9 45 0 0.00 0.0 M 1924-01-08 44 13 28.5 6.3 36 0 0.00 0.0 M 1924-01-09 41 35 38.0 15.9 27 0 0.16 0.0 M 1924-01-10 38 23 30.5 8.5 34 0 0.41 0.0 M 1924-01-11 24 17 20.5 -1.3 44 0 T T M 1924-01-12 21 7 14.0 -7.7 51 0 T T M 1924-01-13 18 -10 4.0 -17.6 61 0 0.00 0.0 M 1924-01-14 25 9 17.0 -4.5 48 0 T T M 1924-01-15 35 20 27.5 6.0 37 0 0.00 0.0 T 1924-01-16 32 1 16.5 -4.9 48 0 0.68 9.5 M 1924-01-17 12 -15 -1.5 -22.8 66 0 0.00 0.0 M 1924-01-18 20 -8 6.0 -15.3 59 0 T T M 1924-01-19 20 0 10.0 -11.2 55 0 0.00 0.0 M 1924-01-20 6 -12 -3.0 -24.2 68 0 0.00 0.0 M 1924-01-21 2 -21 -9.5 -30.7 74 0 0.00 0.0 M 1924-01-22 36 -7 14.5 -6.7 50 0 0.00 0.0 M 1924-01-23 33 16 24.5 3.3 40 0 0.00 0.0 M 1924-01-24 36 11 23.5 2.3 41 0 0.02 T M 1924-01-25 35 -8 13.5 -7.8 51 0 0.00 0.0 M 1924-01-26 8 -8 0.0 -21.3 65 0 0.00 0.0 M 1924-01-27 25 -6 9.5 -11.9 55 0 0.00 0.0 M 1924-01-28 40 19 29.5 8.0 35 0 0.00 0.0 M 1924-01-29 39 33 36.0 14.4 29 0 0.00 0.0 M 1924-01-30 43 27 35.0 13.3 30 0 0.00 0.0 M 1924-01-31 39 25 32.0 10.2 33 0 T 0.0 T

The magnitude of the temperature swings are greater now than in the old days. In order for the CONUS to have a top 5 to top 10 coldest winter there needs to be extensive cold across a large portion of the CONUS which hasn’t happened since the 1970s. These days we can’t get significant Arctic outbreaks without some extreme Arctic warmth like we have been experiencing this winter. No spots in the CONUS this January will see as extreme a departure for the entire month as portions of the Arctic have.

I would say the pattern this winter fits perfectly with what one would expect from a warmer world. First, the extent of the cold this winter was limited compared to what we used to get from Arctic outbreaks across the Northern Hemisphere. The top 5 cold from late January into early February from the Central and Eastern CONUS will only be of a 10 to perhaps 15 day duration. In the old days we could have 60-90 day durations of top 5 cold like in the late 1970s in the CONUS. Plus the record early late November SSW at the time of the lowest Arctic sea ice extent for the late fall into early winter matches model studies which show a link with low Arctic sea ice when combined with a -QBO. Also notice the all-time record warmth out West this winter instead of coast to coast extended cold like we used to get. The presence of the warmth in proximity to the cold can lead to very large temperature swings in some locations.

That’s what makes this top 5 coldest pattern from January 24th through at least February 2nd for the Central and Eastern CONUS so impressive.