2024-2025 La Nina

[40/70 Benchmark]

31 minutes ago, PhiEaglesfan712 said:

The problem was the December one was way too short (it was gone by the end of the month) and the follow up in March took way too long to develop. By the time everything was in place for the cold, it was late April, early May - and it lasted until June - but it was too late for snow. However, the fact that the temperature departures were -2 to -4 in May and June (which is very rare for that time of year) shows that the potential was there. I think if the follow up block was the one in December instead, then the -3/-4 temperature departures would have taken place in January/February or February/March, which would have meant prime opportunities for snow (when it wasn't dry).

You keep saying the March pattern was too late and you are patently incorrect. That huge storm was the first week of the month. That pattern's shortcomings had nothing to do with the calendar.

[donsutherland1]

Just released C3S multi-model outlook for December 2024-February 2025:

North America:

World:

[40/70 Benchmark]

2 hours ago, bluewave said:

22-23 had a record -AO in December and a good follow up in March but the hostile Pacific and Southeast Ridge linkage kept the best snows up into Central and Northern New England. 

I'd roll the dice with that set up and a slightly less amplifed RNA in the mean....at least where I am.

[LakeEffectOH]

47 minutes ago, donsutherland1 said:

Just released C3S multi-model outlook for December 2024-February 2025:

North America:

 

 

This outlook doesn't surprise me with the PDO setup we currently have.  This PDO setup will probably persist into the winter months.

[Typhoon Tip]

58 minutes ago, donsutherland1 said:

Just released C3S multi-model outlook for December 2024-February 2025:

North America:

World:

all we need to do is ease off this eastern continent tuck trough tendency and that would result in a temperature look that satisfies that above rather nicely - in other words ... continuity moving forward. 

this eastern canadian folder over thing has been enabling the eastern lakes, n ov and ne regions into nostalgia for the cold season. lol.  however, i hunch that the last 3 weeks of temp verification might have us being one of the colder regions there is comparing everywhere else outside that small region of 'stolen late summer warmth', on our side of the hemisphere. this started around the 10th of september

i've had cold hands in my house in the mornings this week, and finally ... i flipped the heat pump to heating mode ... meanwhile, it's been in the mid 80s in north fuckum dakota    ha

 

[mitchnick]

1 hour ago, donsutherland1 said:

Just released C3S multi-model outlook for December 2024-February 2025:

North America:

World:

Looks similar to Euro seasonal, if not better for that 3 month period. C3F has +.5-1C push into the Great Lakes while Seasonal is a decent distance west. Plus, it's colder in NW Canada than Seasonal. So with just map, there is confirmation of the Seasonal which is fine by me...assuming, of course, accuracy. 

[George001]

1 hour ago, 40/70 Benchmark said:

You keep saying the March pattern was too late and you are patently incorrect. That huge storm was the first week of the month. That pattern's shortcomings had nothing to do with the calendar.

Agreed the pattern was not too late at all, it just wasn’t a favorable enough pattern. The epic March 2018 pattern set in just as late but that didn’t matter, it still worked out.

[PhiEaglesfan712]

25 minutes ago, 40/70 Benchmark said:

You keep saying the March pattern was too late and you are patently incorrect. That huge storm was the first week of the month. That pattern's shortcomings had nothing to do with the calendar.

I am aware that the pattern started to change around February 25, and yes, there were storms in the last days of February and the beginning of March to the north. However, the warm ground and sun angle made it nearly impossible for snow to happen anywhere south of Newark/NYC, especially after the +10 temperature departures from January 1-February 23/24. The only way it was going to work is if everything fell into place like they did on March 1-2, 2009, and even then a snowstorm wasn't a guarantee. One big difference between 2009 and 2023 is that 2009 had leftover cold from October-January and a snowstorm in early February. We just had very little to no cold to work with in 2023.

I know there's no guarantee it works out if the pattern change happened on December 25, rather than February 25. However, it would have bought us 2 more months for something to happen. Here, in the mid-Atlantic, the sun angle is low enough in January, it can snow even following a +10 departure in November/December. (2016 is a famous example.) But it's darn near impossible to snow in March following a +10 departure in January/February.

[donsutherland1]

43 minutes ago, mitchnick said:

Looks similar to Euro seasonal, if not better for that 3 month period. C3F has +.5-1C push into the Great Lakes while Seasonal is a decent distance west. Plus, it's colder in NW Canada than Seasonal. So with just map, there is confirmation of the Seasonal which is fine by me...assuming, of course, accuracy. 

Taken literally, it would be better than the past two winters. I still suspect that the Great Lakes region will be coooler than what is currently shown.

[Terpeast]

2 minutes ago, donsutherland1 said:

Taken literally, it would be better than the past two winters. I still suspect that the Great Lakes region will be coooler than what is currently shown.

Yeah it checks out with my +2 to +3 call for much of the east, but when warm anomalies happen, they are often more extreme than forecast. My hope is that we can get cold air outbreaks to offset some of the warmth.

[PhiEaglesfan712]

52 minutes ago, George001 said:

Agreed the pattern was not too late at all, it just wasn’t a favorable enough pattern. The epic March 2018 pattern set in just as late but that didn’t matter, it still worked out.

February 2018 was near record warm, but at least there was still some leftover cold from earlier in the season. Don't forget that we got some good cold and snows in late December 2017 and early January 2018.

Years like 2009 and 2018 show that it can snow in March in the mid-Atlantic, despite the strong sun angle, but certain things have to be in place/come together to make it happen. It also helps that those years didn't have a +10 temperature departure for weeks on end like we had in January/February 2023.

[40/70 Benchmark]

1 hour ago, PhiEaglesfan712 said:

I am aware that the pattern started to change around February 25, and yes, there were storms in the last days of February and the beginning of March to the north. 4However, the warm ground and sun angle made it nearly impossible for snow to happen anywhere south of Newark/NYC, especially after the +10 temperature departures from January 1-February 23/2. The only way it was going to work is if everything fell into place like they did on March 1-2, 2009, and even then a snowstorm wasn't a guarantee. One big difference between 2009 and 2023 is that 2009 had leftover cold from October-January and a snowstorm in early February. We just had very little to no cold to work with in 2023.

I know there's no guarantee it works out if the pattern change happened on December 25, rather than February 25. However, it would have bought us 2 more months for something to happen. Here, in the mid-Atlantic, the sun angle is low enough in January, it can snow even following a +10 departure in November/December. (2016 is a famous example.) But it's darn near impossible to snow in March following a +10 departure in January/February.

Hogwash IMO. You got heavy snow, it would have stacked.

[roardog]

9 minutes ago, 40/70 Benchmark said:

Hogwash IMO. You got heavy snow, it would have stacked.

I had nearly a foot of snow in late April 2005. This was after highs in the 80s the week before. This is the equivalent of a mid August sun angle. I don’t think a late Feb sun angle is going to inhibit accumulation in Philadelphia if the snow is coming down at a decent clip. 

[George001]

On 10/9/2024 at 9:34 AM, bluewave said:

ACE hasn’t traditionally had much relationship with the winter pattern outside the really high La Niña ACE years over 180  like 95-96, 05-06, 17-18, and 20-21.

 

Accumulated Cyclone Energy - Atlantic ^[14] 

Season	ACE	TS	HU	MH	Classification
1933	258.57	20	11	6	Extremely active
2005	245.3	28	15	7	Extremely active
1893	231.1475	12	10	5	Extremely active
1926	229.5575	11	8	6	Extremely active
1995	227.1025	19	11	5	Extremely active
2004	226.88	15	9	6	Extremely active
2017	224.8775	17	10	6	Extremely active
1950	211.2825	16	11	6	Extremely active
1961	188.9	12	8	5	Extremely active
1998	181.7675	14	10	3	Extremely active
1887	181.26	19	11	2	Extremely active
1878	180.85	12	10	2	Extremely active
2020	180.3725	30	14	7	Extremely active

Looks like we are going to end up at roughly 140 before the next lull. The average ACE increase from now until the end of hurricane season is roughly 20, so that would put us at around 160 ACE by the end of the hurricane season. We probably will fall short, but I’m starting to think there is a very real shot at going over 180. Likely? No, but stranger things have happened.

[snowman19]

[40/70 Benchmark]

43 minutes ago, George001 said:

Looks like we are going to end up at roughly 140 before the next lull. The average ACE increase from now until the end of hurricane season is roughly 20, so that would put us at around 160 ACE by the end of the hurricane season. We probably will fall short, but I’m starting to think there is a very real shot at going over 180. Likely? No, but stranger things have happened.

Guy I coordinate with expects about another 40 worth of ACE.

[GaWx]

4 hours ago, donsutherland1 said:

Just released C3S multi-model outlook for December 2024-February 2025:

North America:

World:

Don, how does the US map compare to the Oct 1 C3S forecasts for DJF in recent years? Do you have access to those maps to do a comparison? 

[PhiEaglesfan712]

40 minutes ago, roardog said:

I had nearly a foot of snow in late April 2005. This was after highs in the 80s the week before. This is the equivalent of a mid August sun angle. I don’t think a late Feb sun angle is going to inhibit accumulation in Philadelphia if the snow is coming down at a decent clip. 

The problem was we didn't really have the cold air or precip for a snowstorm. The storms kept missing to the north. The cold and precip didn't really come together until the end of April, and by that point, it was too late for snow:

2023-04-28	56	49	52.5	-6.5	12	0	1.33
2023-04-29	61	49	55.0	-4.4	10	0	0.63
2023-04-30	63	52	57.5	-2.2	7	0	1.51

Like why couldn't we get a storm like this during the winter?

 

[donsutherland1]

2 hours ago, Terpeast said:

Yeah it checks out with my +2 to +3 call for much of the east, but when warm anomalies happen, they are often more extreme than forecast. My hope is that we can get cold air outbreaks to offset some of the warmth.

Yes. I agree. Hopefully, there won't be near wall-to-wall warmth.

[donsutherland1]

26 minutes ago, GaWx said:

Don, how does the US map compare to the Oct 1 C3S forecasts for DJF in recent years? Do you have access to those maps to do a comparison? 

Here are the forecasts. For one year, I had to use the September, not October forecast.

[GaWx]

6 minutes ago, donsutherland1 said:

Here are the forecasts. For one year, I had to use the September, not October forecast.

I know it’s not apples to apples since these are probabilities vs anomalies, but am I correct to say that the comparison implies that 2024-5 is probably the warmest Oct (Sep) forecast by a good margin back at least to 2021-2 for the US as a whole?

[donsutherland1]

7 minutes ago, GaWx said:

I know it’s not apples to apples since these are probabilities vs anomalies, but am I correct to say that the comparison implies that 2024-5 is probably the warmest Oct (Sep) forecast by a good margin back at least to 2021-2 for the US as a whole?

I thought I had posted the anomalies. My error. Here they are.

October 2021 for Winter 2021-22:

September 2022 for Winter 2022-23 (October didn't have a DJF map):

October 2023 for Winter 2023-24:

Top to Bottom: Winter 2021-22, 2022-23, 2023-24 Outcomes:

 

[bluewave]

2 hours ago, George001 said:

Looks like we are going to end up at roughly 140 before the next lull. The average ACE increase from now until the end of hurricane season is roughly 20, so that would put us at around 160 ACE by the end of the hurricane season. We probably will fall short, but I’m starting to think there is a very real shot at going over 180. Likely? No, but stranger things have happened.

We are nearly tied with 2016 for ACE. That was one of the only other times there was more ACE in October than August and September combined along with 1970. So the backloaded nature of this season is in the top 3 along with 2016 and 1970. 

[jm1220]

2 hours ago, 40/70 Benchmark said:

Hogwash IMO. You got heavy snow, it would have stacked.

It can definitely snow and stick here in late March even into April. 2018 the best/latest example. 

[GaWx]

26 minutes ago, donsutherland1 said:

I thought I had posted the anomalies. My error. Here they are.

October 2021 for Winter 2021-22:

September 2022 for Winter 2022-23 (October didn't have a DJF map):

October 2023 for Winter 2023-24:

Top to Bottom: Winter 2021-22, 2022-23, 2023-24 Outcomes:

 

Thanks, Don. So, the Oct fcast for DJF is clearly the warmest of these going back to 2021-2. The +1 to +2 in the current one covers nearly all of the US, which is larger coverage than all of these. Note also that none had anything >2. I wonder if that is due to a cold bias. Note also that E Canada is warmer than 2021-2 and 2022-3 although it is less warm than 2023-4.

 So for the E US:

-2021-2 ended up too warm, especially Midwest/Lakes

-2022-3 ended up not warm enough especially NE

-2023-4 ended up not warm enough Midwest/NE

[40/70 Benchmark]

32 minutes ago, bluewave said:

We are nearly tied with 2016 for ACE. That was one of the only other times there was more ACE in October than August and September combined along with 1970. So the backloaded nature of this season is in the top 3 along with 2016 and 1970. 

Both of those seasons are members of my polar analog composite that I made back in August.

https://easternmassweather.blogspot.com/2024/08/preliminary-analysis-of-polar-domain.html

Eastern Mass Weather Preliminary Polar Analogs for Winter 2024-2025

1970

1975

1999

2007

2016

2022

[PhiEaglesfan712]

23 minutes ago, jm1220 said:

It can definitely snow and stick here in late March even into April. 2018 the best/latest example. 

Yes, but you need cold air and precipitation for a snowstorm to happen. We had that in March/April 2018. We just didn't have that in March/April 2023, at least where I lived, until the huge rainstorm at the end of April.

I mean, it's pretty hard to get snow when your late March/early April looks like this:

2023-03-21	61	32	46.5	1.5	18	0	0.00	0.0	0
2023-03-22	64	38	51.0	5.6	14	0	0.00	0.0	0
2023-03-23	62	48	55.0	9.3	10	0	0.42	0.0	0
2023-03-24	59	44	51.5	5.5	13	0	0.12	0.0	0
2023-03-25	49	44	46.5	0.1	18	0	0.23	0.0	0
2023-03-26	63	44	53.5	6.7	11	0	0.00	0.0	0
2023-03-27	66	39	52.5	5.4	12	0	0.15	0.0	0
2023-03-28	53	39	46.0	-1.5	19	0	0.00	0.0	0
2023-03-29	57	37	47.0	-0.9	18	0	T	0.0	0
2023-03-30	48	33	40.5	-7.7	24	0	0.00	0.0	0
2023-03-31	63	35	49.0	0.4	16	0	0.00	0.0	0

2023-04-01	71	50	60.5	11.5	4	0	0.50	0.0	0
2023-04-02	52	39	45.5	-3.9	19	0	0.00	0.0	0
2023-04-03	63	35	49.0	-0.8	16	0	0.00	0.0	0
2023-04-04	77	50	63.5	13.4	1	0	0.00	0.0	0
2023-04-05	72	55	63.5	13.0	1	0	0.00	0.0	0
2023-04-06	83	55	69.0	18.1	0	4	0.27	0.0	0
2023-04-07	59	47	53.0	1.7	12	0	0.00	0.0	0
2023-04-08	51	39	45.0	-6.7	20	0	0.00	0.0	0
2023-04-09	59	36	47.5	-4.6	17	0	0.00	0.0	0
2023-04-10	65	37	51.0	-1.5	14	0	0.00	0.0	0
2023-04-11	74	45	59.5	6.6	5	0	0.00	0.0	0
2023-04-12	83	55	69.0	15.7	0	4	0.00	0.0	0
2023-04-13	86	56	71.0	17.4	0	6	0.00	0.0	0
2023-04-14	84	57	70.5	16.5	0	6	0.00	0.0	0

[40/70 Benchmark]

8 minutes ago, PhiEaglesfan712 said:

Yes, but you need cold air and precipitation for a snowstorm to happen. We had that in March/April 2018. We just didn't have that in March/April 2023, at least where I lived, until the huge rainstorm at the end of April.

I mean, it's pretty hard to get snow when your late March/early April looks like this:

2023-03-21	61	32	46.5	1.5	18	0	0.00	0.0	0
2023-03-22	64	38	51.0	5.6	14	0	0.00	0.0	0
2023-03-23	62	48	55.0	9.3	10	0	0.42	0.0	0
2023-03-24	59	44	51.5	5.5	13	0	0.12	0.0	0
2023-03-25	49	44	46.5	0.1	18	0	0.23	0.0	0
2023-03-26	63	44	53.5	6.7	11	0	0.00	0.0	0
2023-03-27	66	39	52.5	5.4	12	0	0.15	0.0	0
2023-03-28	53	39	46.0	-1.5	19	0	0.00	0.0	0
2023-03-29	57	37	47.0	-0.9	18	0	T	0.0	0
2023-03-30	48	33	40.5	-7.7	24	0	0.00	0.0	0
2023-03-31	63	35	49.0	0.4	16	0	0.00	0.0	0

2023-04-01	71	50	60.5	11.5	4	0	0.50	0.0	0
2023-04-02	52	39	45.5	-3.9	19	0	0.00	0.0	0
2023-04-03	63	35	49.0	-0.8	16	0	0.00	0.0	0
2023-04-04	77	50	63.5	13.4	1	0	0.00	0.0	0
2023-04-05	72	55	63.5	13.0	1	0	0.00	0.0	0
2023-04-06	83	55	69.0	18.1	0	4	0.27	0.0	0
2023-04-07	59	47	53.0	1.7	12	0	0.00	0.0	0
2023-04-08	51	39	45.0	-6.7	20	0	0.00	0.0	0
2023-04-09	59	36	47.5	-4.6	17	0	0.00	0.0	0
2023-04-10	65	37	51.0	-1.5	14	0	0.00	0.0	0
2023-04-11	74	45	59.5	6.6	5	0	0.00	0.0	0
2023-04-12	83	55	69.0	15.7	0	4	0.00	0.0	0
2023-04-13	86	56	71.0	17.4	0	6	0.00	0.0	0
2023-04-14	84	57	70.5	16.5	0	6	0.00	0.0	0

It was because of the pattern, not the time of year. Rest assured, if didn't have a trough ampligying down to the baja out west, then you would have experienced a cold March. It was enough for a good portion of New England, but not for most.

[bluewave]

6 hours ago, PhiEaglesfan712 said:

The problem was the December one was way too short (it was gone by the end of the month) and the follow up in March took way too long to develop. By the time everything was in place for the cold, it was late April, early May - and it lasted until June - but it was too late for snow. However, the fact that the temperature departures were -2 to -4 in May and June (which is very rare for that time of year) shows that the potential was there. I think if the follow up block was the one in December instead, then the -3/-4 temperature departures would have taken place in January/February or February/March, which would have meant prime opportunities for snow (when it wasn't dry).

At least May 2020 delivered.

 

 

[PhiEaglesfan712]

I highly doubt we add 40 ACE towards the end of the year. However, if we do, we could finish with a Top 10 ACE year. (NOTE: Data averages Wunderground & NOAA values for years 2016 and before, NOAA values only for 2017 and later)

1            2005      247.65

2            1933      235.785

3            1893      231.0738

4            1995      227.5513

5            1950      227.1413

6            2004      226.94

7            1926      225.7788

8            2017      224.8775           

9            1961      196.95

10          1998      181.8838

11          2020      180.3725

12          1955      178.585