2024-2025 La Nina

[mitchnick]

11 hours ago, MJO812 said:

Last night's end of Eps got colder.

https://www.tropicaltidbits.com/analysis/models/?model=eps&region=us&pkg=T850a&runtime=2025012500&fh=360

[mitchnick]

2 minutes ago, PhiEaglesfan712 said:

Looks like we're headed for a continuing la nina, a la spring 2022, rather than a flip to el nino like 2006 and 2009. In those years, the la nina had already peaked by February, setting the stage for an el nino to form the following season.

Forcing disappears after this easterly burst with most modeling heading for the COD. Here's the Eps.

https://charts.ecmwf.int/permalinks/time-longitudes-sections-extended-range-forecast-72885

[mitchnick]

Subsurface warming building in the west and spreading east while the subsurface cold has peaked.

 

[snowman19]

10 minutes ago, mitchnick said:

Subsurface warming building in the west and spreading east while the subsurface cold has peaked.

 

That’s something to look at in the spring for clues to what ENSO does next winter

[donsutherland1]

Some updates on last week’s thoughts:

1. Dry weather continued in southern California through the week. No  rainfall was measured in Blythe, Camarillo, Lancaster, Los Angeles, and Palm Springs.

2. An East Coast snowstorm brought lighter amounts of snow to the I-95 area than had been modeled. Snowfall amounts included: Baltimore: 1.0”; Boston: 5.0”; New York City: 1.6”; Newark: 2.4”; Philadelphia: 2.0”; and Washington, DC: 0.3”  

3. A severe cold shot affected the Great Lakes Region and East Coast from Sunday through Thursday. The lowest temperatures were: Baltimore: 6°; Boson: 10°; Chicago: -8° (two subzero lows); Detroit: -3°; Indianapolis: -3° (two subzero lows); New York City: 10°; Newark: 7° (two single-digit lows); Philadelphia: 10°; and, Washington, DC: 15°

Both New York City and Philadelphia had high temperatures of 19° on January 21.  Those were the coldest high temperatures there since December 24, 2022.

4. The Deep South was hit by a historic snowstorm on Tuesday into Wednesday. Snowfall amounts included: Atlanta: 1.1”; Baton Rouge: 7.6”; Charleston: 2.8”; Gulfport: 7.0”; Mobile: 7.5”; New Orleans: 8.0”; Pensacola: 8.9”; Savanah: 1.1”; Tallahassee: 0.1”. Milton (2 N), FL picked up 9.8” of snow. Prior to this storm, the greatest snowfall for Florida was 5.0” during January 9-10, 1800 (officially, the record was 4.0”). Record cold followed the heavy snowfall. Lafayette, LA, with a period of record that goes back to January 1893, set an all-time record low temperature of 4°.

Four Thoughts Going Forward:

1. Some much needed rain will fall in southern California on Sunday through Tuesday. Los Angeles (LAX) could pick up an inch or more of rainfall. Blythe’s record streak without measurable rainfall will also end. Phoenix and Las Vegas will likely also see their second longest stretches without measurable precipitation end.

2. Parts of Texas, including Houston and Dallas could see significant rainfall, especially late in the week.

3. New York City and Philadelphia will likely see little or no precipitation through the end of January. One or both cities could finish with their driest January on record. The current records ae: New York City: 0.58”, 1981 and Philadelphia: 0.45”, 1955.

4. No significant snowstorms (6” or more) are likely in the Great Lakes and Middle Atlantic regions.

Longer-Range:

A slow moderation in temperatures is likely during the start of February. Above normal but not much above normal temperatures could develop in the eastern quarter of the United States after the first week of February.  It could also turn wetter in the Great Lakes Region and parts of the eastern U.S. However, with the AO likely to be predominantly positive through at least the first week of February, the probability of a significant (6” or above) snowstorm in the New York City and Philadelphia areas will be limited.

[GaWx]

5 hours ago, donsutherland1 said:

Some updates on last week’s thoughts:

 

1. Dry weather continued in southern California through the week. No  rainfall was measured in Blythe, Camarillo, Lancaster, Los Angeles, and Palm Springs.

 

2. An East Coast snowstorm brought lighter amounts of snow to the I-95 area than had been modeled. Snowfall amounts included: Baltimore: 1.0”; Boston: 5.0”; New York City: 1.6”; Newark: 2.4”; Philadelphia: 2.0”; and Washington, DC: 0.3”  

 

3. A severe cold shot affected the Great Lakes Region and East Coast from Sunday through Thursday. The lowest temperatures were: Baltimore: 6°; Boson: 10°; Chicago: -8° (two subzero lows); Detroit: -3°; Indianapolis: -3° (two subzero lows); New York City: 10°; Newark: 7° (two single-digit lows); Philadelphia: 10°; and, Washington, DC: 15°

 

Both New York City and Philadelphia had high temperatures of 19° on January 21.  Those were the coldest high temperatures there since December 24, 2022.

 

4. The Deep South was hit by a historic snowstorm on Tuesday into Wednesday. Snowfall amounts included: Atlanta: 1.1”; Baton Rouge: 7.6”; Charleston: 2.8”; Gulfport: 7.0”; Mobile: 7.5”; New Orleans: 8.0”; Pensacola: 8.9”; Savanah: 1.1”; Tallahassee: 0.1”. Milton (2 N), FL picked up 9.8” of snow. Prior to this storm, the greatest snowfall for Florida was 5.0” during January 9-10, 1800 (officially, the record was 4.0”). Record cold followed the heavy snowfall. Lafayette, LA, with a period of record that goes back to January 1893, set an all-time record low temperature of 4°.

 

Four Thoughts Going Forward:

 

1. Some much needed rain will fall in southern California on Sunday through Tuesday. Los Angeles (LAX) could pick up an inch or more of rainfall. Blythe’s record streak without measurable rainfall will also end. Phoenix and Las Vegas will likely also see their second longest stretches without measurable precipitation end.

 

2. Parts of Texas, including Houston and Dallas could see significant rainfall, especially late in the week.

 

3. New York City and Philadelphia will likely see little or no precipitation through the end of January. One or both cities could finish with their driest January on record. The current records ae: New York City: 0.58”, 1981 and Philadelphia: 0.45”, 1955.

 

4. No significant snowstorms (6” or more) are likely in the Great Lakes and Middle Atlantic regions.

 

Longer-Range:

 

A slow moderation in temperatures is likely during the start of February. Above normal but not much above normal temperatures could develop in the eastern quarter of the United States after the first week of February.  It could also turn wetter in the Great Lakes Region and parts of the eastern U.S. However, with the AO likely to be predominantly positive through at least the first week of February, the probability of a significant (6” or above) snowstorm in the New York City and Philadelphia areas will be limited.

Thanks, Don. As I posted in the storm thread, the supposed 1.1” of sleet/snow at KSAV (airport) is not being believed even by the Charleston NWS office (that covers Savannah)! This is an unmanned ASOS and is only checked by an FAA person at a certain time. The CHS met in charge (Brian, who recently moved to CHS from Phil) confirmed to me yesterday that KSAV had a whopping 1.33” of melted liquid equiv and near 100% of this fell with temps under 32 (mainly upper 20s). There was only minimal ZR (outages in the area were a fraction of 1%) and I saw only a little myself in Savannah. That means the 1.33” fell as mainly sleet and snow. I measured about the same melted precip and measured 2.9” of sleet and snow with most being sleet and their precip changed to snow earlier! There are still shaded grassy areas around town with 3”! So, the combo of having ~100% of 1.33” of liquid with temps below 32 , minimal ZR, and 1.1” of IP/SN and considering other SAV area obs (majority of CoCoRaHS reported 2.5-3.5” of mainly sleet) means that even KCHS per yesterday’s telecon isn’t at all believing it’s accuracy. He was very thankful and feels the same frustration. He assured me that it will be thoroughly investigated though he couldn’t at all assure me the official records will change (snowfall and the recorded 0.71” liquid equiv). He said one of the problems on the liquid equiv is that it fell 6PM-6AM (straddled two days) and the observer didn’t wasn’t there at midnight. I suggested they just report the two day total as the storm total and have the equivalent of an asterisk to explain. The 1.1” will also be hard to change due to the observer twice saying it was that. He said it will take months to investigate all the way to the NCDC. I already feel it will be a losing battle. If you have any suggestion please let me know.

Aside: The 1/2018 liq equiv was also severely underreported as ~1/4” when it was really ~3/4” because the measuring device froze up!

Edit: This is extra frustrating because KSAV gets storms like this on average no more often than once a generation. The last time there was one with liquid equiv of 1.33”+ was the late Jan of 1922 precursor to the Washington, DC tragic Knickerbocker snowstorm!! In SAV, it was a severe ZR.

 To have these data reporting issues in our age of advanced tech makes it even more frustrating. And that also gets me thinking about how reliable are 100 year old records.

Edit #2: I’m now picking up my sis from airport. While waiting, l just measured an estimated 2” on the ground of a hard layer) (mainly sleet) and this is over 3 days later!

@Daniel Boone

[donsutherland1]

1 hour ago, GaWx said:

Thanks, Don. As I posted in the storm thread, the supposed 1.1” of sleet/snow at KSAV (airport) is not being believed even by the Charleston NWS office (that covers Savannah)! This is an unmanned ASOS and is only checked by an FAA person at a certain time. The CHS met in charge (Brian, who recently moved to CHS from Phil) confirmed to me yesterday that KSAV had a whopping 1.33” of melted liquid equiv and near 100% of this fell with temps under 32 (mainly upper 20s). There was only minimal ZR (outages in the area were a fraction of 1%) and I saw only a little myself in Savannah. That means the 1.33” fell as mainly sleet and snow. I measured about the same melted precip and measured 2.9” of sleet and snow with most being sleet and their precip changed to snow earlier! There are still shaded grassy areas around town with 3”! So, the combo of having ~100% of 1.33” of liquid with temps below 32 , minimal ZR, and 1.1” of IP/SN and considering other SAV area obs (majority of CoCoRaHS reported 2.5-3.5” of mainly sleet) means that even KCHS per yesterday’s telecon isn’t at all believing it’s accuracy. He was very thankful and feels the same frustration. He assured me that it will be thoroughly investigated though he couldn’t at all assure me the official records will change (snowfall and the recorded 0.71” liquid equiv). He said one of the problems on the liquid equiv is that it fell 6PM-6AM (straddled two days) and the observer didn’t wasn’t there at midnight. I suggested they just report the two day total as the storm total and have the equivalent of an asterisk to explain. The 1.1” will also be hard to change due to the observer twice saying it was that. He said it will take months to investigate all the way to the NCDC. I already feel it will be a losing battle. If you have any suggestion please let me know.

Aside: The 1/2018 liq equiv was also severely underreported as ~1/4” when it was really ~3/4” because the measuring device froze up!

Edit: This is extra frustrating because KSAV gets storms like this on average no more often than once a generation. The last time there was one with liquid equiv of 1.33”+ was the late Jan of 1922 precursor to the Washington, DC tragic Knickerbocker snowstorm!! In SAV, it was a severe ZR.

 To have these data reporting issues in our age of advanced tech makes it even more frustrating. And that also gets me thinking about how reliable are 100 year old records.

Edit #2: I’m now picking up my sis from airport. While waiting, l just measured an estimated 2” on the ground of a hard layer) (mainly sleet) and this is over 3 days later!

I agree with you. From my having seen the changeover to snow/sleet on the observations, I expected a greater accumulation at Savannah. I hope that there will be some measure of quality control and, if appropriate, an adjustment. This was a historic storm and it would be a shame for a bad measurement to minimize what happened at Savannah.

[GaWx]

7 hours ago, snowman19 said:

That’s something to look at in the spring for clues to what ENSO does next winter

New Euro Weeklies trended colder/quite cold Feb 3-9 W 2/3 of US while E 1/6 retains warmth due to SE ridge…will need to see whether or not this cold will eventually be able to make it to the E at least in modified form:

Feb 3-9:

Feb 10-16 trended much colder in E US, where it had been mild, with no AN: this has the look of those cold leftovers making it to E despite a SE ridge pattern:

 

Yesterday’s 2/10-6: mild throughout E US!

 

 

[snowman19]

Region 3.4 dropping like a rock, the lowest of this event….approaching -1.5C. We are now at moderate on the dailies 

[purduewx80]

Looking forward to off-and-on highs in the 70s and an early spring here in ATL.

[so_whats_happening]

On 1/25/2025 at 9:46 AM, GaWx said:

Thanks, Don. As I posted in the storm thread, the supposed 1.1” of sleet/snow at KSAV (airport) is not being believed even by the Charleston NWS office (that covers Savannah)! This is an unmanned ASOS and is only checked by an FAA person at a certain time. The CHS met in charge (Brian, who recently moved to CHS from Phil) confirmed to me yesterday that KSAV had a whopping 1.33” of melted liquid equiv and near 100% of this fell with temps under 32 (mainly upper 20s). There was only minimal ZR (outages in the area were a fraction of 1%) and I saw only a little myself in Savannah. That means the 1.33” fell as mainly sleet and snow. I measured about the same melted precip and measured 2.9” of sleet and snow with most being sleet and their precip changed to snow earlier! There are still shaded grassy areas around town with 3”! So, the combo of having ~100% of 1.33” of liquid with temps below 32 , minimal ZR, and 1.1” of IP/SN and considering other SAV area obs (majority of CoCoRaHS reported 2.5-3.5” of mainly sleet) means that even KCHS per yesterday’s telecon isn’t at all believing it’s accuracy. He was very thankful and feels the same frustration. He assured me that it will be thoroughly investigated though he couldn’t at all assure me the official records will change (snowfall and the recorded 0.71” liquid equiv). He said one of the problems on the liquid equiv is that it fell 6PM-6AM (straddled two days) and the observer didn’t wasn’t there at midnight. I suggested they just report the two day total as the storm total and have the equivalent of an asterisk to explain. The 1.1” will also be hard to change due to the observer twice saying it was that. He said it will take months to investigate all the way to the NCDC. I already feel it will be a losing battle. If you have any suggestion please let me know.

Aside: The 1/2018 liq equiv was also severely underreported as ~1/4” when it was really ~3/4” because the measuring device froze up!

Edit: This is extra frustrating because KSAV gets storms like this on average no more often than once a generation. The last time there was one with liquid equiv of 1.33”+ was the late Jan of 1922 precursor to the Washington, DC tragic Knickerbocker snowstorm!! In SAV, it was a severe ZR.

 To have these data reporting issues in our age of advanced tech makes it even more frustrating. And that also gets me thinking about how reliable are 100 year old records.

Edit #2: I’m now picking up my sis from airport. While waiting, l just measured an estimated 2” on the ground of a hard layer) (mainly sleet) and this is over 3 days later!

@Daniel Boone

Such a shame to read this but this sounds like a training issue in measuring. As a weather observer, we go through training every season/ monthly (depending on what training is needed) to refresh what may come our way. Sounds to me like they did an end of system measurement versus an hourly which would offer a completely different outcome for totals. This is an SWO/Contractor issue that will be looked into because someone will be on the line for such erroneous measurements. This tends to be an issue that comes up in areas that don't experience certain weather conditions. Since the deep south typically does not experience a lot of wintry precip and if this happens to be a newer individual that would make sense. Just like further north around here we get thunderstorms but not often hail or tornadic systems so the training is important.

Also as another aside the equipment being used is very old in most locations with no plans of upgrades anytime soon, if they upgrade it would be AI generated (whenever this comes about) unless it is absolutely necessary to upgrade.

Hope it gets resolved properly.

Edit: just saw the part it is unmanned that would mean either two things it would be a local EMS location that undertakes that role which is probably not properly trained to do procedures like this or it was a tower individual at that location doing the obs which they should know at least a little bit better but can't get on them as they are ATC not weather. This may be an issue that arises down the road if cuts do at some point come to airport weather programs (we will see what happens). If there was no auto during those times it was being monitored by someone which most likely would have been ATC then.

[GaWx]

3 hours ago, purduewx80 said:

Looking forward to off-and-on highs in the 70s and an early spring here in ATL.

I think today’s Euro Weeklies will revert back to warmer than yesterday based on today’s 0Z Euro ens at 360.

[MJO812]

1 hour ago, GaWx said:

I think today’s Euro Weeklies will revert back to warmer than yesterday based on today’s 0Z Euro ens at 360.

TPV is entrenched 

It will not warm in New England and that cold will probably bleed down to NYC now.

The weeklies will get colder 

 

[GaWx]

5 hours ago, MJO812 said:

TPV is entrenched 

It will not warm in New England and that cold will probably bleed down to NYC now.

The weeklies will get colder 

 

Today’s Euro Weeklies for 2/10-16 and 2/17-23 are a bit warmer than they were yesterday in the E US. There remains no BN in the E US for these weeks til the end. Canonical La Niña Feb. but nowhere near enough to match the cold of Jan. Thus this winter will ultimately likely be remembered most for the very cold Jan in much of the country along with the historically snowy Deep South. Major kudos to Euro Weeklies for predicting Jan quite well weeks in advance! We’ll see whether or not anything else quite notable will occur in Feb.

 This much warmer Feb vs Jan has been forecasted by the Euro for a number of weeks:

2/10-16: stronger warmth E US with shade 3 in some areas

 

2/17-23: some slight AN part of MidAtlantic south vs all NN yesterday:

 

 

 

[40/70 Benchmark]

On 1/25/2025 at 7:26 AM, PhiEaglesfan712 said:

Looks like we're headed for a continuing la nina, a la spring 2022, rather than a flip to el nino like 2006 and 2009. In those years, the la nina had already peaked by February, setting the stage for an el nino to form the following season.

2008 also peaked late, and was followed by a healthy el Nino....its the best analog in terms of ONI and is the reason I never gave up on La Nina when most did.

[40/70 Benchmark]

13 hours ago, snowman19 said:

Region 3.4 dropping like a rock, the lowest of this event….approaching -1.5C. We are now at moderate on the dailies 

See, this is why I can't wrap my mind around people hugging the IRI guidance like 9 months out....Christ, just last fall they had La Nina failing.

[Maestrobjwa]

1 hour ago, 40/70 Benchmark said:

2008 also peaked late, and was followed by a healthy el Nino....its the best analog in terms of ONI and is the reason I never gave up on La Nina when most did.

Did you mean 2008-09?

[michsnowfreak]

2 hours ago, GaWx said:

Today’s Euro Weeklies for 2/10-16 and 2/17-23 are a bit warmer than they were yesterday in the E US. There remains no BN in the E US for these weeks til the end. Canonical La Niña Feb. but nowhere near enough to match the cold of Jan. Thus this winter will ultimately likely be remembered most for the very cold Jan in much of the country along with the historically snowy Deep South. Major kudos to Euro Weeklies for predicting Jan quite well weeks in advance! We’ll see whether or not anything else quite notable will occur in Feb.

 This much warmer Feb vs Jan has been forecasted by the Euro for a number of weeks:

2/10-16: stronger warmth E US with shade 3 in some areas

 

2/17-23: some slight AN part of MidAtlantic south vs all NN yesterday:

 

 

 

Feb looks stormy in many areas, so easily there could be notable things for some areas in Feb. 

[40/70 Benchmark]

1 hour ago, Maestrobjwa said:

Did you mean 2008-09?

Yes.