bluewave

Yeah, everything lined up perfectly for a below 0°reading in NYC on 2-14-16. Record blocking north of Alaska driving the core of the cold and Arctic high pressure down at a perfect angle. Didn’t matter that it was one of the warmest winters on record or how much UHI there was. We couldn’t even get to or below 0° in NYC during the much colder winters in 13-14 or 14-15. Here at HVN some of our coldest readings have occurred in recent years on strong northerly flow events. Even though 22-23 was another top warmest winter, we still were able to go below 0° here like in 2016. So shorter Arctic outbreaks are still very possible even if we haven’t had a top 10 coldest winter month since February 2015 and top 10 coldest winter since the 1970s. Coldest temperatures at HVN since 47-48 Series Summary for NEW HAVEN TWEED AP, CT - Dec through Feb Click column heading to sort ascending, click again to sort descending. 1 1947-1948 -8 31 2 1960-1961 -7 0 3 2015-2016 -6 0 - 1956-1957 -6 0 4 1967-1968 -5 0 5 2008-2009 -4 0 - 1962-1963 -4 0 6 2022-2023 -3 0 - 2014-2015 -3 0 - 2003-2004 -3 0 - 1966-1967 -3 0 - 1948-1949 -3 0 Climatological Data for NEW HAVEN TWEED AP, CT - February 2023 Click column heading to sort ascending, click again to sort descending. Sum 1314 762 - - 774 0 0.67 Average 46.9 27.2 37.1 5.1 - - - Normal 40.2 23.9 32.0 - 923 0 2023-02-01 37 27 32.0 1.8 33 0 T 2023-02-02 40 20 30.0 -0.3 35 0 0.00 2023-02-03 39 3 21.0 -9.4 44 0 T 2023-02-04 30 -3 13.5 -17.0 51 0 0.00 2023-02-05 43 29 36.0 5.4 29 0 0.00 2023-02-06 56 27 41.5 10.8 23 0 0.00 2023-02-07 41 26 33.5 2.7 31 0 0.07 2023-02-08 53 29 41.0 10.1 24 0 0.00 2023-02-09 52 25 38.5 7.4 26 0 0.00 2023-02-10 62 35 48.5 17.3 16 0 0.00 2023-02-11 47 27 37.0 5.7 28 0 0.00 2023-02-12 47 25 36.0 4.5 29 0 0.00 2023-02-13 54 38 46.0 14.4 19 0 0.01 2023-02-14 55 32 43.5 11.7 21 0 0.00 2023-02-15 58 33 45.5 13.5 19 0 0.00 2023-02-16 68 47 57.5 25.4 7 0 0.03 2023-02-17 56 31 43.5 11.2 21 0 0.21 2023-02-18 42 27 34.5 2.0 30 0 0.00 2023-02-19 48 31 39.5 6.8 25 0 0.00 2023-02-20 58 41 49.5 16.6 15 0 0.00 2023-02-21 48 36 42.0 8.9 23 0 T 2023-02-22 44 27 35.5 2.3 29 0 0.05 2023-02-23 41 36 38.5 5.1 26 0 0.05 2023-02-24 44 24 34.0 0.4 31 0 0.02 2023-02-25 30 19 24.5 -9.3 40 0 0.03 2023-02-26 42 17 29.5 -4.6 35 0 0.00 2023-02-27 42 22 32.0 -2.3 33 0 0.06 2023-02-28 37 31 34.0 -0.5 31 0 0.14

Brooklyn got down to -4° on 1-21-85 when Newark was -8°. So really not sure why Central Park couldn’t go below -2° as even LGA was -3°. I was out on the Long Beach Boardwalk that morning viewing the greatest display of Arctic seasmoke and steamnadoes that I saw there. It was my only time there experiencing temps on the Long Beach Boardwalk in the 0° to -1° range combined with 40-50mph gusts. Data for January 21, 1985 through January 21, 1985 Click column heading to sort ascending, click again to sort descending. NJ ESSEX FELLS SERVICE BLDG COOP -14 NJ CHARLOTTEBURG RESERVOIR COOP -12 NJ WANAQUE RAYMOND DAM COOP -12 NY MIDDLETOWN 2 NW COOP -10 NJ CRANFORD COOP -10 NY PORT JERVIS COOP -9 NJ NEWARK LIBERTY INTL AP WBAN -8 NJ LITTLE FALLS COOP -8 NY YORKTOWN HEIGHTS 1W COOP -8 NY WEST POINT COOP -7 NJ CANOE BROOK COOP -7 CT DANBURY COOP -7 NY GARNERVILLE COOP -6 NJ PLAINFIELD COOP -6 NJ TETERBORO AIRPORT WBAN -6 NY WALDEN 1 ESE COOP -6 NY DOBBS FERRY-ARDSLEY COOP -5 NY NY WESTERLEIGH STAT IS COOP -5 NY SCARSDALE COOP -5 CT NORWICH PUBLIC UTILITY PLANT COOP -5 NY NEW YORK AVE V BROOKLYN COOP -4 CT STAMFORD 5 N COOP -4 NY WESTCHESTER CO AP WBAN -4 NY WESTBURY COOP -4 NY LAGUARDIA AIRPORT WBAN -3 CT MOUNT CARMEL COOP -3 NY PATCHOGUE 2 N COOP -3 NY WANTAGH CEDAR CREEK COOP -3 NY NY CITY CENTRAL PARK WBAN -2 CT NORWALK GAS PLANT COOP -2 CT IGOR I SIKORSKY MEMORIAL AIRPORT WBAN -2 NY JFK INTERNATIONAL AIRPORT WBAN -2

Yeah, the only reason NYC didn’t drop below -10° with all the amazing Arctic outbreaks between December 1976 and January 1994 was the wind direction during those events. That era was known for W to NW flow Arctic outbreaks with the Arctic highs dropping to our SW. February 1934 had a record 1050 MB high north of Cleveland with a N to NNW flow. Many of those winters in the CONUS were as cold or even colder than any of the 1930s Arctic outbreaks. The other time NYC dipped below -10° was December 1917 and that was on a northerly flow down the Hudson Valley also. The only other known time since 1850 that NYC dipped below -10° was 1-10-1859 and that was probably a northerly flow Arctic outbreak also. https://www.ncei.noaa.gov/pub/orders/IPS/IPS-83B7C91F-D13A-41BD-8DA6-B04751ABCF72.pdf https://www.ncei.noaa.gov/pub/orders/IPS/IPS-B52AC2FB-E0E2-4D85-B828-754842FD43C9.pdf k City Temperatures Monday, January 10, 1859 Max. –1.5° Min. –12.0° Mean: -6.75° 12 a.m.: -1.5 (i) 4 a.m.: -2.5 (ii) 7 a.m.: -3.7 (ii) 11 a.m.: -7.5 (ii) 12 noon: -9.0 (iii) 2 p.m.: -3.8 (ii) 9 p.m.: -8.0 (ii) 12 a.m.: -12.0 (iv) (i) Estimate; (ii) Erasmus Hall, Brooklyn, N.Y. readings; (iii) Coldest Weather In Seventy Years. The New York Times, 11 Jan. 1859; (iv) Jamaica, Queens

Yeah, the Euro and GFS were too suppressed to the south with the snowfall forecast being 10-20” too low while the NAM did a great job. https://ams.confex.com/ams/44Broadcast/webprogram/Paper294758.html The snowstorm of 22-23 January 2016 in the northeastern United States produced one of the largest snowfalls ever recorded in the metropolitan corridor that extends from Washington, DC to New York, NY. The indication for major cyclogenesis with a potential significant east coast snowfall was predicted 12 days and 6 days in advance by the GFS and the ECMWF models, respectively. Early and consistent model forecasts led to high confidence in predicting very heavy snowfall for Virginia, Maryland and southeastern Pennsylvania including the cities of Washington, Baltimore, and Philadelphia. Further, the models consistently indicated that there would be a very strong gradient in snowfall accumulation near the northern extent of the precipitation shield, which was predicted to fall within 100km north or south of the New York City metropolitan region. Variations in the northern extent of snowfall across the operational and ensemble model suites led to significant uncertainty in snowfall predictions for New York City. Just 12 hours before the onset of precipitation in New York City, deterministic model forecasts varied greatly with snowfall forecasts from the GFS, ECMWF, NAM, and WSI's RPM being 12, 11, 26, and 29 inches respectively. Further, NCEP's short-range ensemble forecasts (SREF) had even larger spread with ranges from 1" to over 32" of snow. Retrospective analysis of global model forecasts and of NCEP's short-range ensemble forecasts system (SREF) revealed that forecasts based on the WRF-ARW dynamical core (including WSI RPM) were much more consistent and accurate at predicting the northern extent of heavy precipitation than forecasts based on other dynamical cores (NAM, GFS, and ECMWF). This presentation will provide both an analysis of the available real-time numerical weather prediction models, as well as an analysis of retrospective runs of the RPM system (using its WRF-ARW core) to reveal what components of the WRF-ARW contributed to the accurate snowfall forecasts, especially in the northern part of this snowstorm.

UHI can’t stop CAA when the airmass is cold enough. This is why Chicago had colder temperatures in the 1980s with much more UHI than the late 1880s. Cities like NYC always needed strong CAA since around 1900 when UHI become firmly established in NYC. The same goes for areas near the Long Island Sound and the South Shore. Coastal areas need the winds to stay up in order to deliver the coldest readings. Manhattan Island probably was never a great radiational cooling spot even before the Dutch arrived. The February 1934 Arctic outbreak was much colder than anything we have seen since then. If we could recreate that Arctic airmass again urbanized areas would have no problem dropping from-10 to -20 as Chicago recently proved with -20s back in January 2019. You need the cold right down to the the coast like in February 1934 in order to get so much ice on the local waterways which we have not seen since. Click on top title below to get video to load

February 1934 was the last time we had widespread -10° to -20° readings near the coast. Monthly Data for February 1934 for Upton NY NWS CWA Click column heading to sort ascending, click again to sort descending. NJ CANOE BROOK COOP -26 NY WALDEN 2 NE COOP -24 NY CARMEL COOP -24 NJ CHARLOTTEBURG RESERVOIR COOP -21 CT COLCHESTER 2 W COOP -21 CT NORWALK COOP -20 CT BRIDGEPORT COOP -20 NY PORT JERVIS COOP -19 NY BEDFORD HILLS COOP -19 NJ LITTLE FALLS COOP -18 NY SCARSDALE COOP -18 NJ PLAINFIELD COOP -17 NJ RIDGEFIELD COOP -17 NY WEST POINT COOP -17 CT NEW LONDON COOP -17 NJ PATERSON COOP -16 CT WATERBURY ANACONDA COOP -16 CT WATERBURY CITY HALL COOP -16 NJ ELIZABETH COOP -15 NY NY CITY CENTRAL PARK WBAN -15 NJ JERSEY CITY COOP -14 NJ NEWARK LIBERTY INTL AP WBAN -14 NY WORLD TRADE CENTER WBAN -14 NY FLUSHING COOP -14 NY MOUNT VERNON COOP -14 NY FARMINGDALE 2 NE COOP -12 NY BRIDGEHAMPTON COOP -12 NY SETAUKET STRONG COOP -11 NY CUTCHOGUE COOP -10

New all-time highest wind gust for Ireland.

Yeah, when you have rely on snow cover and the winds going calm there are usually many fewer record lows across a wider area. This is why we didn’t have that many record lows around the region this week. The Arctic outbreaks from the 70s to 90s had both much colder air masses and strong CAA in addition to radiational cooling. Even the places that did get below 0° like SMQ aren’t having Januaries a cold as they did in past at the same low temperature levels. So the more impressive cold this time around was more isolated. It’s much easier these days to get record highs than record lows. Jan 25…..coldest of month …-9°…….avg….26.5° Feb 15…..coldest of month….-9°……..avg….20.3° Jan 14….coldest of month…..-9………avg….23.0° Jan 94….coldest of month….-11°…….avg….20.8°

This was the first -9° around SMQ since 14-15. They came close in January 18. While they only got a little colder in January 1994, other areas in NJ were much colder than anything seen in recent decades. Sussex County, NJ approached -30°. The CAA was so intense in January 1985 that Newark was -8° while SMQ only -7°. Newark got down to -7° in January 1982 and SMQ made it down to -12°. SMQ was -15° in January 1981. It’s interesting that the coldest Arctic outbreaks across the U.S. in recent years have been more radiational cooling based with snow cover as we just saw in Louisiana. This was also the case in Illinois in January 2019. The intensity of the cold was also shorter lasting than when we would see record cold in the past. The older Arctic outbreaks in the 70s through 90s had significantly lower 850mb to surface temps and were with a much more extensive geographic footprint. So places near the coast and in urban areas which rely on CAA and and much colder airmass frequently saw record lows during that era. Monthly Data for January 2025 for New Jersey Click column heading to sort ascending, click again to sort descending. BELVIDERE BRIDGE COOP -17 Belvidere Area ThreadEx -17 SUSSEX AIRPORT WBAN -14 CHARLOTTEBURG RESERVOIR COOP -10 SOMERSET AIRPORT WBAN -9 Monthly Data for January 2018 for New Jersey Click column heading to sort ascending, click again to sort descending. AEROFLEX-ANDOVER AIRPORT WBAN -9 MILLVILLE MUNICIPAL AIRPORT WBAN -8 WANAQUE RAYMOND DAM COOP -8 SUSSEX 1 NW COOP -7 SOMERSET AIRPORT WBAN -7 INDIAN MILLS 2 W COOP -6 FREEHOLD-MARLBORO COOP -5 ESTELL MANOR COOP -5 ATSION COOP -5 Monthly Data for February 2015 for New Jersey Click column heading to sort ascending, click again to sort descending. SUSSEX AIRPORT WBAN -16 SUSSEX 1 NW COOP -15 AEROFLEX-ANDOVER AIRPORT WBAN -14 CHARLOTTEBURG RESERVOIR COOP -12 TOCKS ISLAND COOP -10 SOMERSET AIRPORT WBAN -9 FLEMINGTON 5 NNW COOP -8 Atlantic City Area ThreadEx -6 BELVIDERE BRIDGE COOP -6 BOONTON 1 SE COOP -6 Belvidere Area ThreadEx -6 ATLANTIC CITY INTL AP WBAN -6 CANOE BROOK COOP -5 INDIAN MILLS 2 W COOP -5 Monthly Data for January 2014 for New Jersey Click column heading to sort ascending, click again to sort descending. SUSSEX 1 NW COOP -9 MILLVILLE MUNICIPAL AIRPORT WBAN -9 SOMERSET AIRPORT WBAN -9 SUSSEX AIRPORT WBAN -9 BELVIDERE BRIDGE COOP -8 Belvidere Area ThreadEx -8 INDIAN MILLS 2 W COOP -6 FLEMINGTON 5 NNW COOP -4 ESTELL MANOR COOP -4 Monthly Data for January 1994 for New Jersey Click column heading to sort ascending, click again to sort descending. SUSSEX 1 NW COOP -29 NEWTON COOP -26 SUSSEX 8 NNW COOP -20 LONG VALLEY COOP -18 Belvidere Area ThreadEx -17 BELVIDERE BRIDGE COOP -17 FLEMINGTON 5 NNW COOP -15 PHILLIPSBURG-EASTON BRIDGE COOP -13 BOONTON 1 SE COOP -13 CHARLOTTEBURG RESERVOIR COOP -13 SOMERVILLE 4 NW COOP -11 WANAQUE RAYMOND DAM COOP -11 LAMBERTVILLE COOP -10 CANOE BROOK COOP -10 ESSEX FELLS SERVICE BLDG COOP -9 MOORESTOWN 4 E COOP -8 LITTLE FALLS COOP -8 WAYNE COOP -8 EWING 3 WNW COOP -7 Trenton Area ThreadEx -7 PLAINFIELD COOP -7 CRANFORD COOP -7 PHILADELPHIA/MT. HOLLY WFO COOP -6 SEABROOK FARMS COOP -6 GLASSBORO 2 NE COOP -6 HIGHTSTOWN 2 W COOP -6 BELLEPLAIN STA FOREST COOP -5 TUCKERTON 2 NE COOP -5 WOODSTOWN PITTSGROV 4E COOP -5 INDIAN MILLS 2 W COOP -5 PEMBERTON COOP -5 TOMS RIVER COOP -5 NEW BRUNSWICK 3 SE COOP -5 New Brunswick Area ThreadEx -5 LODI COOP -5 Monthly Data for January 1985 for New Jersey Click column heading to sort ascending, click again to sort descending. SEABROOK FARMS COOP -24 HIGH POINT PARK COOP -16 ESSEX FELLS SERVICE BLDG COOP -14 BOONTON 1 SE COOP -14 EWING 3 WNW COOP -12 Trenton Area ThreadEx -12 CHARLOTTEBURG RESERVOIR COOP -12 WANAQUE RAYMOND DAM COOP -12 NEWTON COOP -11 MOORESTOWN 4 E COOP -10 Belvidere Area ThreadEx -10 CRANFORD COOP -10 LONG VALLEY COOP -10 BELVIDERE BRIDGE COOP -10 ATLANTIC CITY INTL AP WBAN -9 MORRIS PLAINS 1 W COOP -9 SUSSEX 1 NW COOP -9 Atlantic City Area ThreadEx -9 TOMS RIVER COOP -8 NEWARK LIBERTY INTL AP WBAN -8 CANOE BROOK COOP -8 LITTLE FALLS COOP -8 Newark Area ThreadEx -8 WOODSTOWN PITTSGROV 4E COOP -7 SOMERVILLE 4 NW COOP -7 ESTELL MANOR COOP -7 TUCKERTON 2 NE COOP -6 HAMMONTON 1 NE COOP -6 INDIAN MILLS 2 W COOP -6 LAMBERTVILLE COOP -6 NEW BRUNSWICK 3 SE COOP -6 New Brunswick Area ThreadEx -6 PLAINFIELD COOP -6 TETERBORO AIRPORT WBAN -6 GLASSBORO 2 NE COOP -5 AUDUBON COOP -5 PEMBERTON COOP -5 LONG BRANCH-OAKHURST COOP -5 FREEHOLD-MARLBORO COOP -5 HIGHTSTOWN 2 W COOP -5 Monthly Data for January 1982 for New Jersey Click column heading to sort ascending, click again to sort descending. TOMS RIVER COOP -19 MORRIS PLAINS 1 W COOP -16 HIGH POINT PARK COOP -15 BELLEPLAIN STA FOREST COOP -14 PEMBERTON COOP -14 INDIAN MILLS 2 W COOP -13 LAKEHURST NAS WBAN -13 SOMERVILLE 4 NW COOP -12 ESTELL MANOR COOP -12 Trenton Area ThreadEx -11 EWING 3 WNW COOP -11 CHARLOTTEBURG RESERVOIR COOP -11 LONG VALLEY COOP -10 ESSEX FELLS SERVICE BLDG COOP -10 NEWTON COOP -10 MILLVILLE MUNICIPAL AIRPORT WBAN -9 HAMMONTON 1 NE COOP -9 FREEHOLD-MARLBORO COOP -9 LAMBERTVILLE COOP -9 FLEMINGTON 5 NNW COOP -9 BOONTON 1 SE COOP -9 WANAQUE RAYMOND DAM COOP -9 SUSSEX 1 NW COOP -9 New Brunswick Area ThreadEx -8 WOODSTOWN PITTSGROV 4E COOP -8 NEW BRUNSWICK 3 SE COOP -8 Newark Area ThreadEx -7 TUCKERTON 2 NE COOP -7 AUDUBON COOP -7 HIGHTSTOWN 2 W COOP -7 PLAINFIELD COOP -7 NEWARK LIBERTY INTL AP WBAN -7 LITTLE FALLS COOP -7 Monthly Data for January 1981 for New Jersey Click column heading to sort ascending, click again to sort descending. NEWTON COOP -24 SUSSEX 1 NW COOP -22 WANAQUE RAYMOND DAM COOP -20 LONG VALLEY COOP -17 FLEMINGTON 5 NNW COOP -16 SOMERVILLE 4 NW COOP -15 CANOE BROOK COOP -15 CHARLOTTEBURG RESERVOIR COOP -13 INDIAN MILLS 2 W COOP -12 BELVIDERE COOP -12 Belvidere Area ThreadEx -12 BELLEPLAIN STA FOREST COOP -11 HIGH POINT PARK COOP -11 PEMBERTON COOP -10 LAMBERTVILLE COOP -10 MORRIS PLAINS 1 W COOP -10 BOONTON 1 SE COOP -10 FREEHOLD-MARLBORO COOP -9 ESSEX FELLS SERVICE BLDG COOP -9 HIGHTSTOWN 2 W COOP -8 PLAINFIELD COOP -8 CRANFORD COOP -8 NEW BRUNSWICK 3 SE COOP -7 New Brunswick Area ThreadEx -7 ATLANTIC CITY INTL AP WBAN -6

Ireland is a really beautiful country. Had some friends that did a guided tour during the fall for the first time and they loved it. When I lived back in Long Beach we had a very large Irish community in the West End.

This is going to be one of the most severe sting jet wind events for Ireland in recent times.

Very extreme windstorm headed for Ireland caused them to send the hurricane hunters over there.

For Caribou, Maine to go +4.9 so far through January 22nd and Charleston, West Virginia -10.7° is a first. This almost reminds me of all the over the top warm ups we have seen in recent years. But now during the Arctic outbreaks the warmest relative to the means are further north into New England.

Both the core of cold and the storm track got suppressed to our south this month. This has become a common occurrence in recent years. In the old days the Northeast would have been much colder when places to our south were this cold. Just goes to show how the geographic footprint of the Arctic outbreaks has been shrinking in recent years. We also saw this in January 2019 and February 2021.

We can simplify things even more and just look at any 10 year period for a place with at least a 60 year long snowfall measurement period. The lowest 10 year running snowfall average on record at JFK was 18.0” from 67-68 to 76-77. The current 7 year running average snowfall at JFK starting in 18-19 is down to 13.6” which is the lowest. I will update it again at the end of this season since we are just beyond the midpoint in a La Nina winter which usually has most of its snow by the end of January. The previous lowest 7 year running average was 15.8” from 85-86 to 91-92. That 7 year average jumped up in the following seasons due to the record snowfall in 93-94 and 95-96. The lowest previous 10 year running average snowfall ended in 76-77 at 18.0”. We had the record 77-78 season the next year. So we are really going to have to pick up the snowfall rates next 3 to 4 years in order to prevent the 2020s from becoming the lowest cardinal decade along with a new low for any 10 year period. JFK is representative of most of our 60 year+ climate sites across the whole area.