January 2025

[Dark Star]

38 minutes ago, mgerb said:

A likely factor: besides imparting sensible heat to the lower atmosphere, the lakes also impart moisture. Slightly increased boundary layer moisture->higher dew points (and perhaps more clouds)->warmer TMINs. This definitely happens, especially closer to the Great Lakes. Down here, to a much lower degree. 

Unquantifiable, therefore, not (officially) a factor here.

[mgerb]

19 minutes ago, Dark Star said:

Unquantifiable, therefore, not (officially) a factor here.

OK....don't know what you mean.

It is quantifiable. Look at a DP map during the winter upwind vs downwind of the Great Lakes. 

[psv88]

Highs are going to be in the mid 40s for much of this week. Winter ended real fast apparently. No cold in sight 

[jm1220]

5 minutes ago, psv88 said:

Highs are going to be in the mid 40s for much of this week. Winter ended real fast apparently. No cold in sight 

When we lose the cross polar source region and go back to modified polar, no surprise the temp forecasts go up as a result. 

[Dark Star]

44 minutes ago, mgerb said:

OK....don't know what you mean.

It is quantifiable. Look at a DP map during the winter upwind vs downwind of the Great Lakes. 

and you can quantify the effect on NYC and it takes in account the effects of downsloping, cloud cover, snow cover, and all other variables?

[Dark Star]

1 hour ago, bluewave said:

Yeah, the much warmer minimum temperature departures than the maximums across the Northeast this month were very obvious.

 

Ever hear that high winds impedes radiational cooling?  If you can show me the calculations, then maybe it can be considered.  Of course you would have to taken in heating due to downsloping, etc...

[mgerb]

28 minutes ago, Dark Star said:

and you can quantify the effect on NYC and it takes in account the effects of downsloping, cloud cover, snow cover, and all other variables?

Never said that. I'm referring to air mass modification vis-à-vis the transport of polar air masses over the Great Lakes, particularly just downwind. The effect is reduced the further you travel from the lakes, but it's not zero. 

[bluewave]

41 minutes ago, Dark Star said:

Ever hear that high winds impedes radiational cooling?  If you can show me the calculations, then maybe it can be considered.  Of course you would have to taken in heating due to downsloping, etc...

High winds plus the record January cloud cover coming off the lakes both worked in tandem to warm the minimum departures. So it’s no surprise that the brief radiational cooling around the 22nd occurred during a relaxation of the flow over the Lakes in conjunction with the snow cover.

It’s also true that the stronger winds across the Great Lakes picked up clouds and downsloped into JFK adding enough warmth so JFK only dropped to 13° which was a little warmer than the 12 in December. This was only the 3rd such occurrence of the January minimum not exceeding the December minimum at JFK in 24 years.

So this January can make for an interesting study of the highly anomalous temperature pattern in the Northeast relative to areas further south. Northern Maine going +5 with West Virginia at -10 never occurred before in modern times during January. Add in the warmest year on record in Canada and latest freeze-up on Hudson Bay along with record Great Lakes warmth to start the season. And we can’t forget the near record 500 mb vortex east of New England for any January acting has a huge gyre causing the flow to travel down from the Hudson Bay and across the Great Lakes. The rapidly warming climate especially since mid 2023 continues to set records.

 

Monthly Lowest Min Temperature for New York-Kennedy Airport Area, NY (ThreadEx)
Click column heading to sort ascending, click again to sort descending.

2024-2025	12	13	12
2023-2024	25	18	18
2022-2023	7	29	7
2021-2022	24	9	9
2020-2021	18	15	15
2019-2020	17	19	17
2018-2019	24	3	3
2017-2018	9	4	4
2016-2017	19	13	13
2015-2016	34	12	12
2014-2015	26	8	8
2013-2014	20	3	3
2012-2013	28	12	12
2011-2012	21	13	13
2010-2011	19	6	6
2009-2010	16	14	14
2008-2009	14	7	7
2007-2008	20	14	14
2006-2007	19	9	9
2005-2006	15	14	14
2004-2005	12	6	6
2003-2004	21	1	1
2002-2003	18	7	7
2001-2002	21	22	21
2000-2001	14	15	14

 

[LibertyBell]

38 minutes ago, Dark Star said:

Ever hear that high winds impedes radiational cooling?  If you can show me the calculations, then maybe it can be considered.  Of course you would have to taken in heating due to downsloping, etc...

wind direction might have something to do with it too.  If we had more of  a northerly wind rather than a westerly wind, we would have much less downsloping and a direct shot of arctic air.

 

[bluewave]

19 minutes ago, LibertyBell said:

wind direction might have something to do with it too.  If we had more of  a northerly wind rather than a westerly wind, we would have much less downsloping and a direct shot of arctic air.

 

It’s why areas most east of the Hudson this month couldn’t come anywhere close the lows from early February 2023 with that impressive northerly flow which avoided the Great Lakes.

 

[steve392]

Winds are absolutely howling up here in Mahwah.  Looks like its  snowing but its all the dried up rock salt getting blown all over.

[Dark Star]

1 hour ago, mgerb said:

Never said that. I'm referring to air mass modification vis-à-vis the transport of polar air masses over the Great Lakes, particularly just downwind. The effect is reduced the further you travel from the lakes, but it's not zero. 

I will daresay less than 1 degree, and a lot less than winds reducing the effect of overnight radiational cooling, downsloping, lack of snow cover.  Until someone can quantify it for NYC, it is a non item.  

[mgerb]

10 minutes ago, Dark Star said:

I will daresay less than 1 degree, and a lot less than winds reducing the effect of overnight radiational cooling, downsloping, lack of snow cover.  Until someone can quantify it for NYC, it is a non item.  

But there IS research on this topic that quantifies climate with/without the Great Lakes. For example, see the paper below. Doesn't answer how much the GLs affect NYC-area climate specifically (falls just outside the "Great Lakes Basin" domain), but it's apparent that the large thermal inertia of the GLs has a notable effect on regional climate. That wouldn't completely disappear outside the domain, but no doubt it's reduced compared to areas closer to the lakes. 

https://journals.ametsoc.org/view/journals/clim/26/3/jcli-d-12-00140.1.pdf

[psv88]

19 minutes ago, Dark Star said:

I will daresay less than 1 degree, and a lot less than winds reducing the effect of overnight radiational cooling, downsloping, lack of snow cover.  Until someone can quantify it for NYC, it is a non item.  

Even if there was an impact why would it only impact night time temps and not day time? That’s what I’m not getting…the lakes only impact the temps at night?

[mgerb]

1 minute ago, psv88 said:

Even if there was an impact why would it only impact night time temps and not day time? That’s what I’m not getting…the lakes only impact the temps at night?

It really would affect both, but would expect to see it more at night when increased moisture and (perhaps) clouds could reduce overnight cooling. During the day, temps are largely driven by solar insolation, and the presence or lack of can overtake other factors. Just spitballing though; it's all very complicated and depends on many factors. Point is, the GLs contain huge thermal inertia that greatly affects climate within the 50-100 miles downwind. Less clear as you get down towards our area and I'd agree that any effect is likely very subtle. 

[Allsnow]

1 hour ago, mgerb said:

It really would affect both, but would expect to see it more at night when increased moisture and (perhaps) clouds could reduce overnight cooling. During the day, temps are largely driven by solar insolation, and the presence or lack of can overtake other factors. Just spitballing though; it's all very complicated and depends on many factors. Point is, the GLs contain huge thermal inertia that greatly affects climate within the 50-100 miles downwind. Less clear as you get down towards our area and I'd agree that any effect is likely very subtle. 

Thank you 

[donsutherland1]

Temperatures rose into the 40s across the Middle Atlantic Region today. Baltimore and Washington, DC topped out at 50° and 54° respectively.

The mild weather will likely continue through tomorrow before another cold front arrives. The front could be accompanied by some snow flurries. Behind the front, it will turn briefly colder, but the coldest anomalies will occur across Upstate New York and New England.

The cold won't rival that of last week. Although the cold air mass will originate in northern Russia, that region has been experienccing near record and record warmth. As a result, the air mass will not be exceptionally cold when it reaches eastern North America.

January will likely end with a rebound in temperatures and rain developing across the Middle Atlantic region. New York City and Philadelphia could pick up 0.50" or more. Upstate New York State and northern New England could see snow and ice.

The AO is now positive and is expected to remain predominantly positive through at least the first week of February. As a result, prospects for a 6" or above snowstorm in the New York City area will be limited. Since 1950, just 2 of 19 (11%) of storms with an AO of +2.000 or above during January 15-February 15 saw 6" or more of snow in New York City. Opportunities for a 6" or above snowstorm could persist for parts of southern New England, including Boston, through the first week of February.   

The ENSO Region 1+2 anomaly was -0.4°C and the Region 3.4 anomaly was -0.9°C for the week centered around January 22. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.08°C and the ENSO Region 3.4 anomaly has averaged -0.80°C. La Niña conditions are underway and will likely persist into the start of spring.

The SOI was +14.28 today.

The preliminary Arctic Oscillation (AO) was +1.847 today.

Based on sensitivity analysis applied to the latest guidance, there is an implied near 100% probability that New York City will have a colder than normal January (1991-2020 normal). January will likely finish with a mean temperature near 30.7° (3.2° below normal).

 

[bluewave]

Tomorrow looks like the kind of westerly flow day that high temperatures and winds can beat expectations with the very steep lapse rates and deep mixed layer. A 45-50 day for temps and wind gusts. This has been the strongest westerly flow January of the 2020s.

 

[Brian5671]

Should have been a wind advisory for most of the areas today with gusts to 45-50

[gravitylover]

1 hour ago, bluewave said:

Tomorrow looks like the kind of westerly flow day that high temperatures and winds can beat expectations with the very steep lapse rates and deep mixed layer. A 45-50 day for temps and wind gusts. This has been the strongest westerly flow January of the 2020s.

 

After an anamolously long period of easterlies. 

[SACRUS]

 

Up to 44 today.  Snow 75% gone.

[SACRUS]

 

Records:

Highs:

EWR: 62 (2002)
NYC: 66 (1916)
LGA: 60 (2002)
JFK: 60 (2002)


Lows:

EWR: -4 (1935)
NYC: -2 (1925)
LGA: 7 (2005)
JFK: 6 (2005)

Historical: 

 

1887: Snowflakes "as large as milk pans" fell at Fort Keogh of Montana. The flakes, which were said to measure 15 inches across and 8 inches thick, hold the unofficial size record!

1922 - The "Knickerbocker" storm immobilized the city of Washington D.C. The storm produced 28 inches of snow in 32 hours, and the heavy snow caused the roof of the Knickerbocker movie theatre to collapse killing 96 persons. (David Ludlum)

1963 - The low of -34 degrees at Cynthiana, KY, equalled the state record established just four days earlier at Bonnieville. (The Weather Channel)

 

1969: Heavy rains of tropical origin that began on 1/18 ended on this day. As much as 50 inches of rain fell at 7,700 feet. 31 inches of rain fell on the south slopes of Mt. San Gorgonio, 15.5 inches at San Jacinto Peak, around ten inches at Banning, less than one inch from Indio southeast. 91 were reported dead from flooding and mudslides all over California and state-wide.

 

1977: The Blizzard of '77 was one of the worst winter storms to hit southern Ontario and upstate New York. With the rapid onset of the storm, about 2,000 students in the Niagara region were stranded overnight in schools. 

 

1986: The Space Shuttle Challenger broke apart at 11:39 am EST, 73 seconds after liftoff from the Kennedy Space Center at Cape Canaveral, Florida, on a frigid morning. Starting in the 20s, the ground temperature at liftoff was 36 degrees. Morton Thiokol recommended not launching if the liftoff temperature was below 53 degrees. The cold was blamed for causing the O-rings on the Shuttle's external booster to fail, leading to the explosion. Low-level wind shear also played a factor. 

1987 - A storm moving out of the Central Rockies into the Northern Plains Region produced up to a foot of snow in the Colorado Rockies, and wind gusts to 99 mph at Boulder CO. High winds in Colorado caused 5.6 million dollars damage. (National Weather Summary) (Storm Data)

1988 - Barometric pressure readings of 30.55 inches at Miami FL, 30.66 inches at Tampa FL, and 30.72 inches at Apalachicola FL were all-time record high readings for those locations. (National Weather Summary)

1989 - Nome, AK, reported an all-time record low reading of 54 degrees below zero, and the temperature at Fairwell AK dipped to 69 degrees below zero. Deadhorse AK reported a morning low of 49 degrees below zero, and with a wind chill reading of 114 degrees below zero. In the Lower Forty-eight States, a winter storm over Colorado produced up to 15 inches of snow around Denver. (National Weather Summary) (Storm Data)

1990 - Strong and gusty winds prevailed across the northwestern U.S., and heavy snow continued over the mountains of Washington State and Oregon. In Idaho, Mullan received seven inches of snow, and winds gusted to 65 mph southeast of Burley. Heavy rain soaked coastal sections of western Oregon. Rainfall totals of 1.20 inches at Portland and 1.57 inches at Eugene were records for the date. Winds in Oregon gusting to 60 mph downed power lines in Umatilla County knocking out power to more than 13,000 homes, just prior to the kick-off of the "Super Bowl" game. (National Weather Summary) (Storm Data)

[SACRUS]

 

NYC

Jan 28, 2022 - 8.3 inches of snowfall

[LibertyBell]

7 hours ago, bluewave said:

Tomorrow looks like the kind of westerly flow day that high temperatures and winds can beat expectations with the very steep lapse rates and deep mixed layer. A 45-50 day for temps and wind gusts. This has been the strongest westerly flow January of the 2020s.

 

I hope this is a sign for a lot of westerly flow for the summer  We could use another summer that's hot and not humid a la 1966 and 2010.

[weathermedic]

Wind advisory for the entire area today 

[bluewave]

12 hours ago, gravitylover said:

After an anamolously long period of easterlies. 

These were some of the strongest westerlies since Janaury 1977. So this used to be a much colder pattern. Janaury 1977 was nearly 10° colder on average around the area than this month was. But at least we can brag that we got some version of the Jan 77 analog to repeat in a much warmer fashion.

[Dark Star]

20 hours ago, bluewave said:

High winds plus the record January cloud cover coming off the lakes both worked in tandem to warm the minimum departures. So it’s no surprise that the brief radiational cooling around the 22nd occurred during a relaxation of the flow over the Lakes in conjunction with the snow cover.

It’s also true that the stronger winds across the Great Lakes picked up clouds and downsloped into JFK adding enough warmth so JFK only dropped to 13° which was a little warmer than the 12 in December. This was only the 3rd such occurrence of the January minimum not exceeding the December minimum at JFK in 24 years.

So this January can make for an interesting study of the highly anomalous temperature pattern in the Northeast relative to areas further south. Northern Maine going +5 with West Virginia at -10 never occurred before in modern times during January. Add in the warmest year on record in Canada and latest freeze-up on Hudson Bay along with record Great Lakes warmth to start the season. And we can’t forget the near record 500 mb vortex east of New England for any January acting has a huge gyre causing the flow to travel down from the Hudson Bay and across the Great Lakes. The rapidly warming climate especially since mid 2023 continues to set records.

 

Monthly Lowest Min Temperature for New York-Kennedy Airport Area, NY (ThreadEx)
Click column heading to sort ascending, click again to sort descending.

2024-2025	12	13	12
2023-2024	25	18	18
2022-2023	7	29	7
2021-2022	24	9	9
2020-2021	18	15	15
2019-2020	17	19	17
2018-2019	24	3	3
2017-2018	9	4	4
2016-2017	19	13	13
2015-2016	34	12	12
2014-2015	26	8	8
2013-2014	20	3	3
2012-2013	28	12	12
2011-2012	21	13	13
2010-2011	19	6	6
2009-2010	16	14	14
2008-2009	14	7	7
2007-2008	20	14	14
2006-2007	19	9	9
2005-2006	15	14	14
2004-2005	12	6	6
2003-2004	21	1	1
2002-2003	18	7	7
2001-2002	21	22	21
2000-2001	14	15	14

 

That doesn't prove anything.  Radiational cooling is always minimized with stronger winds, and is at it s peak with no winds.   This theory is going nowhere without true modeling.  While there may be a minute difference in warming from the unfrozen lakes, this is at best a hypothesis that needs an in depth study.  

[bluewave]

14 minutes ago, Dark Star said:

That doesn't prove anything.  Radiational cooling is always minimized with stronger winds, and is at it s peak with no winds.   This theory is going nowhere without true modeling.  While there may be a minute difference in warming from the unfrozen lakes, this is at best a hypothesis that needs an in depth study.  

What theory are you talking about? The planet has warmed tremendously since the 1970s. So even a roughly similar 500 mb pattern won’t be as cold. 

[LibertyBell]

13 hours ago, gravitylover said:

After an anamolously long period of easterlies. 

and hopefully a drier pattern after an anomalously wet period that lasted for a few decades.

[LibertyBell]

13 minutes ago, bluewave said:

What theory are you talking about? The planet has warmed tremendously since the 1970s. So even a roughly similar 500 mb pattern won’t be as cold. 

I think he's talking about the lakes causing higher night time lows for the east coast.