January 2025

[LibertyBell]

2 hours ago, Dark Star said:

150 years seems like a good enough data base.  Except we only use 20 years (or 30 years according to Mgerb) for our averages.  And although we don't have records going back before they were officially recorded, I thought we had a fairly reliable estimates from things such as tree cross sections, sedimentations, ice core sampling?  

I suggest we use 60 years so all the airport data matches the data at the park.  60 years is enough, the climate in the early 1900s was radically differently, let alone anything before that.

 

[the_other_guy]

I can’t believe we’re still arguing about this cold January.

 

It was a cold January!

 

And what made it even feel colder was because we’ve had a series of warm Januarys.

 

please don’t minimize how big of a fucking deal it is that we’re gonna finish with a -3 or a minus anything in January.

 

The same people that want to remind us all the time of how warm it is versus a 30 year average now want to minimize the fact that we have a cold month.

Bizzare

[LibertyBell]

2 hours ago, bluewave said:

The CAA into West Virginia which has been very impressive tracked south of the Great Lakes. So the airmass didn’t travel over the warmer Great Lakes with the much lower ice than normal. Plus Erie which is the closest Lake to them is one of the few with sufficient ice cover. Remember, the Great Lakes warmth is a result of the record warmth in Canada which had their warmest year on record. So it’s a symptom of the overall pattern and not the cause. Same goes for the delayed freeze-up on Hudson Bay.

The Northeast being closer to this warmer region to the north is why the cold was muted this month in the Northeast relative to areas to our south. Past instances when West Virginia was so cold in January were significantly colder in the Northeast. This is the first time that parts of Northern Maine are +5 with West Virginia at -10. So this is something new for the Eastern US.

In the old days it didn’t matter that the core of the cold went to our south. That PV lobe would have been far more expansive covering the Northeast and Eastern Canada. So as the climate continues to warm, the geographic footprint of these Arctic Outbreaks will continue to shrink. We saw a version of this smaller sized Arctic outbreak in February 2021 and January 2019. Much smaller areas of Arctic cold focusing into a smaller area than Arctic outbreaks of the past.

 

The size of our winter storms is also getting smaller.

 

[LibertyBell]

44 minutes ago, donsutherland1 said:

Temperatures again reached 40° or above in much of the Middle Atlantic region. The mild weather will likely continue through Wednesday before another cold front arrives. The front could be accompanied by some snow flurries. Behind the front, it will turn 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.

The guidance has accelerated the onset of rainfall on Friday. As a result, prospects for a record dry month have decreased. Nevertheless, Poughkeepsie and White Plains could still surpass their January records.

Precipitation amounts through January 27th and January Records:

Islip: 0.37" (Record: 0.51", 1970)
Mount Pocono: 0.51" (Record: 0.61", 1990)
New York City-Central Park: 0.45" (Record: 0.58", 1981)
New York City-LaGuardia Airport: 0.35" (Record: 0.51", 1981)
Newark: 0.34" (Record: 0.45", 1981)
Philadelphia: 0.39" (Record: 0.45", 1955)
Poughkeepsie: 0.12" (Record: 0.43", 1970)
White Plains: 0.18" (Record: 0.44", 1955)

Out West, Blythe, CA saw its record 300-day streak without measurable precipitation end today.

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 +11.22 today.

The preliminary Arctic Oscillation (AO) was +2.467 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 30.3° (3.6° below normal).

 

Don what caused the acceleration in the rainfall? Is it because of the quicker retreat of the arctic airmass preceding it?

[NorthShoreWx]

7 hours ago, jm1220 said:

Patchy down here in places with full sun, on the south shore where full sun there’s little left. It’s nice to have the snow cover for the days we have and it definitely helped temps get down to the single digits overnight. 

Full sun areas here, like school grounds, have good snow cover.  Cover is thinner near trees...kinda the opposite of usual.

[NorthShoreWx]

6 hours ago, Allsnow said:

I can’t get behind the Great Lakes argument 

 

Open lakes definitely add warmth to the air flowing over them, but when cold air is advecting into this region from the west or southwest, the lakes have little to do with warming here.

Hudson Bay was a bigger deal for a bit, but it's closed up now.

I'd be more impressed with the lake argument if I saw a reasonable study of how, when, and how much modification we see down here.  It would not be a simple study...wind speed, humidity, wind direction with height, heat transfers related to lake effect formation (evaporation - endothermic and deposition - exothermic), and probably tons of things that I would have no clue about

I'm sure the effect is non-zero, but how significant is it under different conditions?

[bluewave]

1 hour ago, Dark Star said:

As a stubborn old guy, I first measure the actual temperature.  After that, then I look at the wind and wind chill effect temperature.  for sure, the wind chills were extremely uncomfortable at times this January, but the actual air temperature was more representative of January (based on the past 150 years or so of data).

January 1985 was the last time that I got to experience wind chills close to -30° on the Long Beach Boardwalk. 
 

https://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=46&network=NY_ASOS&zstation=JFK&var=wcht&month=jan&_r=t&dpi=100&_fmt=png

 

[TheClimateChanger]

4 hours ago, donsutherland1 said:

Temperatures again reached 40° or above in much of the Middle Atlantic region. The mild weather will likely continue through Wednesday before another cold front arrives. The front could be accompanied by some snow flurries. Behind the front, it will turn 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.

The guidance has accelerated the onset of rainfall on Friday. As a result, prospects for a record dry month have decreased. Nevertheless, Poughkeepsie and White Plains could still surpass their January records.

Precipitation amounts through January 27th and January Records:

Islip: 0.37" (Record: 0.51", 1970)
Mount Pocono: 0.51" (Record: 0.61", 1990)
New York City-Central Park: 0.45" (Record: 0.58", 1981)
New York City-LaGuardia Airport: 0.35" (Record: 0.51", 1981)
Newark: 0.34" (Record: 0.45", 1981)
Philadelphia: 0.39" (Record: 0.45", 1955)
Poughkeepsie: 0.12" (Record: 0.43", 1970)
White Plains: 0.18" (Record: 0.44", 1955)

Out West, Blythe, CA saw its record 300-day streak without measurable precipitation end today.

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 +11.22 today.

The preliminary Arctic Oscillation (AO) was +2.467 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 30.3° (3.6° below normal).

 

Too bad January hath not 30 days.

[bluewave]

4 hours ago, NorthShoreWx said:

Open lakes definitely add warmth to the air flowing over them, but when cold air is advecting into this region from the west or southwest, the lakes have little to do with warming here.

Hudson Bay was a bigger deal for a bit, but it's closed up now.

I'd be more impressed with the lake argument if I saw a reasonable study of how, when, and how much modification we see down here.  It would not be a simple study...wind speed, humidity, wind direction with height, heat transfers related to lake effect formation (evaporation - endothermic and deposition - exothermic), and probably tons of things that I would have no clue about

I'm sure the effect is non-zero, but how significant is it under different conditions?

We had several factors in play. Warmest year on record in Canada. With the secondary effects of delaying the freeze-up on Hudson Bay and the Great Lakes. So this lead to the surface temperature departures modifying much more than the 850 mb temperature departures near and to the east of the Great Lakes with the dominant westerly flow. So the core of the cold departures at the surface was significantly smaller than at 850mb.

 

 

[psv88]

20 minutes ago, bluewave said:

We had several factors in play. Warmest year on record in Canada. With the secondary effects of delaying the freeze-up on Hudson Bay and the Great Lakes. So this lead to the surface temperature departures modifying much more than the 850 mb temperature departures near and to the east of the Great Lakes with the dominant westerly flow. So the core of the cold departures at the surface was significantly smaller than at 850mb.

 

 

Look at the maps you posted. The surface cold was also modified WEST of the lakes. Are you saying the wind blew northeast across the lakes and warmed up the Dakotas?

[NorthShoreWx]

21 minutes ago, bluewave said:

We had several factors in play. Warmest year on record in Canada. With the secondary effects of delaying the freeze-up on Hudson Bay and the Great Lakes. So this lead to the surface temperature departures modifying much more than the 850 mb temperature departures near and to the east of the Great Lakes with the dominant westerly flow. So the core of the cold departures at the surface was significantly smaller than at 850mb.

 

 

Interesting disparity between the surface and 850 anomalies.  The biggest warm anomalies are showing east of Hudson Bay with some bleed down as far as Maine.

[TheClimateChanger]

6 hours ago, bluewave said:

Cold departures don’t mean what they used to in such a rapidly warming climate. New Brunswick which has a record back to 1893 is currently at 28.6°. That’s  a -3.1° departure so far against the warmest 1991-2020 climate normals. It would have been a run of the mill cold month during 1961 to 1990 with a departure around -0.4°. The actual temperature is close to January 2018. Having the 30th coldest January average temperature isn’t that big of a deal. But it feels colder relative to how warm the recent winters have been.

 

Time Series Summary for New Brunswick Area, NJ (ThreadEx) - Month of Jan
Click column heading to sort ascending, click again to sort descending.

1	1977	19.5	0
2	1918	20.2	0
3	1893	21.4	0
4	1912	21.9	0
5	1982	22.2	1
-	1940	22.2	0
6	1970	22.6	0
7	1981	22.7	0
8	1904	22.8	0
9	1994	23.6	2
10	1988	24.0	0
-	1920	24.0	0
11	2004	24.3	0
12	1948	24.4	0
13	1961	25.1	0
14	1945	25.2	0
15	2014	25.5	0
-	1984	25.5	0
16	1971	25.6	0
17	1985	25.9	0
18	1976	26.0	0
19	2003	26.5	0
20	2009	26.7	0
21	1978	26.8	0
22	2011	26.9	0
-	1936	26.9	0
23	1905	27.1	0
24	1925	27.2	0
25	2015	27.4	0
26	1968	27.5	0
27	1957	27.7	0
28	1965	28.1	0
-	1922	28.1	0
-	1895	28.1	0
	1996	28.4	1
29	1969	28.5	0
-	1935	28.5	0
-	1914	28.5	0
30	2025	28.6	5
-	2018	28.6	I0

I'm inclined to agree with you on this point.  I get told on certain subforums here that top 5/top 10 hottest months, seasons, years aren't that big of a deal. Forgive me for not finding a month where historically more than 1 in every 3 years were colder. And the historical rate was probably more like 1 in 2 before the recent warm period.

[NorthShoreWx]

28 minutes ago, bluewave said:

We had several factors in play. Warmest year on record in Canada. With the secondary effects of delaying the freeze-up on Hudson Bay and the Great Lakes. So this lead to the surface temperature departures modifying much more than the 850 mb temperature departures near and to the east of the Great Lakes with the dominant westerly flow. So the core of the cold departures at the surface was significantly smaller than at 850mb.

 

 

Side note; not shown on these maps, but has anyone noticed how warm the winter has been in eastern Europe (i.e., Russia, Ukraine, Belarus)?  NYC has mostly been colder than Moscow lately.

[TheClimateChanger]

5 hours ago, NorthShoreWx said:

Full sun areas here, like school grounds, have good snow cover.  Cover is thinner near trees...kinda the opposite of usual.

This is apparently a natural phenomenon. I was recently reading "Temperature Differences in Harvard Forest and their Significance" by Dr. Herbert A. Rasche, for the U.S. Army Environmental Protection Research Division (1958). Figure 100 in the report shows what are termed "melt rings" around the trees in Town Line Swamp Knoll in March 1948. Apparently, the dark trees must warm up and melt the snow around them.

[bluewave]

8 hours ago, psv88 said:

Look at the maps you posted. The surface cold was also modified WEST of the lakes. Are you saying the wind blew northeast across the lakes and warmed up the Dakotas?

Read my original post that you quoted. The modification west of the Great Lakes is probably more related to the warmth adjacent to that region in Canada. Plus the modification in areas like Minnesota and Wisconsin is obviously less than that experienced here in the Northeast from the maps I posted. So your characterization of the maps is incorrect. 

[LibertyBell]

9 hours ago, TheClimateChanger said:

Too bad January hath not 30 days.

All months should have 30 days, the whole idea of 31 days is stupid.  

[LibertyBell]

8 hours ago, NorthShoreWx said:

Side note; not shown on these maps, but has anyone noticed how warm the winter has been in eastern Europe (i.e., Russia, Ukraine, Belarus)?  NYC has mostly been colder than Moscow lately.

Yes, it's like the heatwave they had a few years ago.  Also, barely any snow at all in Alaska.

[LibertyBell]

8 hours ago, TheClimateChanger said:

This is apparently a natural phenomenon. I was recently reading "Temperature Differences in Harvard Forest and their Significance" by Dr. Herbert A. Rasche, for the U.S. Army Environmental Protection Research Division (1958). Figure 100 in the report shows what are termed "melt rings" around the trees in Town Line Swamp Knoll in March 1948. Apparently, the dark trees must warm up and melt the snow around them.

It's actually rather ingenious.  Nature creates its own micro environment.

PS-- did you ever read about how trees in the Amazon control their own rainfall?

[bluewave]

8 hours ago, TheClimateChanger said:

I'm inclined to agree with you on this point.  I get told on certain subforums here that top 5/top 10 hottest months, seasons, years aren't that big of a deal. Forgive me for not finding a month where historically more than 1 in every 3 years were colder. And the historical rate was probably more like 1 in 2 before the recent warm period.

They began to use 30 year departures as the basis for the climate normals when we were in more of a stable climate regime prior to 1980. This was in the era before the rapid climate warming took off from the 1980s especially into the 2020s. In those days the departures were more aligned with the top 10 coldest and warmest months. So a -3 month now is close to normal for earlier period. No chance any more of a top  10 or even top 20 cold month with such a departure. But a +2 to +3 month can be top 10 or top 15 warmest with ease. This is why portions of the Northeast have had over 50 top 10 warmest months since 2010 to only 1 top 10 coldest. The global temperature monitoring sites use an earlier baseline like 1850 to 1900 and don’t have this issue.

[Dark Star]

6 minutes ago, bluewave said:

They began to use 30 year departures as the basis for the climate normals when we were in more of a stable climate regime prior to 1980. This was in the era before the rapid climate warming took off from the 1980s especially into the 2020s. In those days the departures were more aligned with the top 10 coldest and warmest months. So a -3 month now is close to normal for earlier period. No chance any more of a top  10 or even top 20 cold month with such a departure. But a +2 to +3 month can be top 10 or top 15 warmest with ease. This is why portions of the Northeast have had over 50 top 10 warmest months since 2010 to only 1 top 10 coldest. The global temperature monitoring sites use an earlier baseline like 1850 to 1900 and don’t have this issue.

Good points.  I think this topic could use its own thread.  

[Dark Star]

13 hours ago, NorthShoreWx said:

Open lakes definitely add warmth to the air flowing over them, but when cold air is advecting into this region from the west or southwest, the lakes have little to do with warming here.

Hudson Bay was a bigger deal for a bit, but it's closed up now.

I'd be more impressed with the lake argument if I saw a reasonable study of how, when, and how much modification we see down here.  It would not be a simple study...wind speed, humidity, wind direction with height, heat transfers related to lake effect formation (evaporation - endothermic and deposition - exothermic), and probably tons of things that I would have no clue about

I'm sure the effect is non-zero, but how significant is it under different conditions?

As I have said, too many variables to make a generalized statement of the effects of the Great Lakes on NYC temperatures.  And surely, why would the effect be greater at night than during the day?

[LibertyBell]

11 minutes ago, bluewave said:

They began to use 30 year departures as the basis for the climate normals when we were in more of a stable climate regime prior to 1980. This was in the era before the rapid climate warming took off from the 1980s especially into the 2020s. In those days the departures were more aligned with the top 10 coldest and warmest months. So a -3 month now is close to normal for earlier period. No chance any more of a top  10 or even top 20 cold month with such a departure. But a +2 to +3 month can be top 10 or top 15 warmest with ease. This is why portions of the Northeast have had over 50 top 10 warmest months since 2010 to only 1 top 10 coldest. The global temperature monitoring sites use an earlier baseline like 1850 to 1900 and don’t have this issue.

How long will it take for us to change and adopt the global method too?

[Dark Star]

14 hours ago, the_other_guy said:

I can’t believe we’re still arguing about this cold January.

 

It was a cold January!

 

And what made it even feel colder was because we’ve had a series of warm Januarys.

 

please don’t minimize how big of a fucking deal it is that we’re gonna finish with a -3 or a minus anything in January.

 

The same people that want to remind us all the time of how warm it is versus a 30 year average now want to minimize the fact that we have a cold month.

Bizzare

 

[bluewave]

5 minutes ago, Dark Star said:

Good points.  I think this topic could use its own thread.  

You can see how the small cold departure over the area back in December disappears as we go back to the earlier climate normal periods. 
 

 

[LibertyBell]

2 minutes ago, bluewave said:

You can see how the small cold departure over the area back in December disappears as we go back to the earlier climate normal periods. 
 

 

Chris, what does it look like using the global method?

[bluewave]

33 minutes ago, LibertyBell said:

Chris, what does it look like using the global method?

Those charts don’t go back that far since they are more geared for modern departures. If we use the 1871-1900 January means for NYC, then this month so far is +0.3° rather than the -3.5° of 1991-2020. But even getting an average January vs the older climo is an accomplishment these days. The last really cold January in NYC was back in 2004. That was the 11th coldest January on record. So even using the 1871-1900 means it was still -5.2°. 

[LibertyBell]

1 minute ago, bluewave said:

Those charts don’t go back that far since they are more geared for modern departures. If we use the 1871-1900 January means for NYC, then this month so far is +0.3° rather than the -3.5° of 1991-2020. But even getting an average January vs the older climo is an accomplishment these days. The last really cold January in NYC was back in 2004. That was the 11th coldest January in record. So even using the 1871-1900 means it was still -5.2°. 

The only historically cold winter months I remember since the 80s ended are January 1994, January 2004 and February 2015.

 

[Dark Star]

1 hour ago, bluewave said:

You can see how the small cold departure over the area back in December disappears as we go back to the earlier climate normal periods. 
 

 

Thank you!

[mgerb]

1 hour ago, Dark Star said:

As I have said, too many variables to make a generalized statement of the effects of the Great Lakes on NYC temperatures.  And surely, why would the effect be greater at night than during the day?

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. 

[bluewave]

24 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. 

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