2024-2025 La Nina

[LakePaste25]

31 minutes ago, LibertyBell said:

why don't we get snowfall like that here when our SST are record warm?

In Japan, it’s usually cold air advection driven ocean effect snow, similar to lake effect snow off the great lakes. Far easier to get that when you’re east of a large body of water as opposed to the Atlantic where you need the southern and northern stream to phase and a favorable storm track, otherwise it’s mostly cold and dry.

[LibertyBell]

1 minute ago, LakePaste25 said:

In Japan, it’s usually cold air advection driven ocean effect snow, similar to lake effect snow off the great lakes. Far easier to get that when you’re east of a large body of water as opposed to the Atlantic where you need the southern and northern stream to phase and a favorable storm track. 

so theoretically for long island to get that kind of snow, they'd have to be like 50 miles east of where they are and then get the snow off the prevailing westerlies passing over warmer water and dumping the snow on the east side?

 

[LakePaste25]

4 minutes ago, LibertyBell said:

so theoretically for long island to get that kind of snow, they'd have to be like 50 miles east of where they are and then get the snow off the prevailing westerlies passing over warmer water and dumping the snow on the east side?

 

Yeah exactly. The longer the fetch across water the better. Of course you still generally need cyclonic flow, but a weak clipper or a storm passing offshore over the atlantic would probably be enough to do that. A developing 50/50 low lodged under a block would produce it for several days.

[LibertyBell]

32 minutes ago, LakePaste25 said:

Yeah exactly. The longer the fetch across water the better. Of course you still generally need cyclonic flow, but a weak clipper or a storm passing offshore over the atlantic would probably be enough to do that. A developing 50/50 low lodged under a block would produce it for several days.

I thought maybe some elevation to cause orographic lift would also help (like it does on the Tug Plateau), but that location in Japan is near sea level.

 

[Stormchaserchuck1]

Tropical jet in NW Russia!

That's a 5820dm anomaly in NW Russia in mid-Winter. The frame before looks like it's >+600dm anomaly. Maybe bluewave has something on how record breaking it is. 

[bluewave]

5 hours ago, Stormchaserchuck1 said:

Tropical jet in NW Russia!

That's a 5820dm anomaly in NW Russia in mid-Winter. The frame before looks like it's >+600dm anomaly. Maybe bluewave has something on how record breaking it is. 

It’s a new 500 mb record for this time of year.

 

 

Mika Rantanen

‪@mikarantane.bsky.social‬

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That is a huge blocking predicted to form over NW Russia. Record-breaking in intensity (for the time of the year), with 500 hPa levels half a kilometre higher than normal. It's like a stone in a river that directs the warm, moist air flow from the North Atlantic towards the Arctic.

 

ALT

 

ALT

February 4, 2025 at 8:36 AM

Everybody can

 

 

[bluewave]

On 2/5/2025 at 10:08 PM, LibertyBell said:

Is this near Sapporo, Chris? Is this like our lake effect snow?

 

 

[LibertyBell]

14 hours ago, bluewave said:

It’s a new 500 mb record for this time of year.

 

 

 

Mika Rantanen

‪@mikarantane.bsky.social‬

 

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That is a huge blocking predicted to form over NW Russia. Record-breaking in intensity (for the time of the year), with 500 hPa levels half a kilometre higher than normal. It's like a stone in a river that directs the warm, moist air flow from the North Atlantic towards the Arctic.

 

ALT

 

ALT

February 4, 2025 at 8:36 AM

Everybody can

 

 

What caused this?

[bluewave]

8 hours ago, LibertyBell said:

What caused this?

The record KB block driving the Siberian Airmass SE along with the record SSTs near Japan. 
 

 

[LibertyBell]

30 minutes ago, bluewave said:

The record KB block driving the Siberian Airmass SE along with the record SSTs near Japan. 
 

 

That's very interesting, the Kara Block is what drove the sudden change in the 2015-16 winter too that eventually led to the HECS.  I wonder if the Kara Block is the reason why we're seeing the sudden change in the predictions for this month too.

[bluewave]

Just now, LibertyBell said:

That's very interesting, the Kara Block is what drove the sudden change in the 2015-16 winter too that eventually led to the HECS.  I wonder if the Kara Block is the reason why we're seeing the sudden change in the predictions for this month too.

The KB block is definitely the reason we saw the shift on model forecasts for February. The wave break which just occurred with the record low east of Hudson Bay wasn’t forecast very well back in late January. So this record block is forecast to retrograde back into the AO region. 

[donsutherland1]

Some updates on last week’s thoughts:  

1. Heavy rain affected northern California. Through Thursday, Redding picked up 7.60” of rain for the week.  The 4.33” that fell on Sunday broke the daily record of 4.20” for February 2 that was set in 1915. That was also the highest daily rainfall on record for any day in February and the 6^th highest daily rainfall on record.

2. Only light snow was recorded in the Washington, DC to New York City region and Chicago and Detroit areas. Snowfall amounts for February 3-6 included: Billings: 5.8”; Great Falls: 4.1”. A light accumulating snowfall occurred in Rapid City, but the amount was listed as “Missing” as of this post.

3. Very warm weather affected parts of the West. Denver reached 68° on February 3 (just below its daily mark of 70°). Oklahoma demolished its record high of 78° on February 3 with a high of 84°.  Phoenix tied daily records on February 2 (82°) and February 3 (86°). It also set a new daily record on February 4 with a high of 86°. The peak warmth occurred somewhat earlier in Little Rock with a near record high of 77° on February 3. Nashville reached a record high of 78° on February 6. The week concluded with near record to record heat in parts of Texas. Rio Grande Village reached 100°, the second earliest such reading on record for the United States.

Three Thoughts Going Forward:

1. A significant rainstorm could move into southern and central California late in the week. Rainfall of 2” or more is likely in Los Angeles and San Francisco.

2. The New York City area will likely experience its biggest snowstorm of the season so far tonight into tomorrow. The biggest storm so far this season is 1.8”. Boston and parts of southern New England will see a significant (6” or above) snowfall. A second storm could bring a moderate (4”+) to perhaps significant (6”+) snowfall to Washington, DC near midweek. For reference, the last time Washington, DC saw two 6” or above snowstorms in a winter was 2013-2014.

3. A moderate (4” or above) to significant (6” or above) snowfall is possible in Chicago and Detroit Wednesday into Thursday.

Longer-Range:

The preponderance of guidance has now shifted toward a cooler than normal temperatures in much of the eastern United States, except for the Southeast. Precipitation for the Great Lakes Region and Northeast could be above normal during the second half of February. The Southwest will likely wind up warmer than normal.

[George BM]

The Dec/Jan MEIv2 index came in at exactly -1 (-1.00).

[GaWx]

2024-5 has a good chance to end up with the strongest +PNA for a non-El Nino winter since at least 1949-50.

Edit: Current highest +PNA DJFs back to 1949-50 are El Niño winters of 1976-7 and 2015-6. It actually isn’t out of the realm of realistic possibilities for 2024-5 to even exceed those and become the new highest!

[PhiEaglesfan712]

Eagles win the Super Bowl, we're getting a lot of snow the next 3 days, and a parade on Friday. Not sure anyone else has it any better.

[snowman19]

It’s do or die time. We have a limited window starting next week and into the following week to do something snow wise with the high latitude (-AO/-NAO) blocking we get. There is growing evidence that by the time we get to the beginning of March, all the blocking breaks down, MJO forcing goes back to the IO and Maritime Continent and the SPV strengthens substantially…
 

 

 

 

 

 

 

 

 

[roardog]

1 hour ago, snowman19 said:

It’s do or die time. We have a limited window starting next week and into the following week to do something snow wise with the high latitude (-AO/-NAO) blocking we get. There is growing evidence that by the time we get to the beginning of March, all the blocking breaks down, MJO forcing goes back to the IO and Maritime Continent and the SPV strengthens substantially…
 

 

 

 

 

 

 

 

 

It’s met spring by then and I feel like the mid Atlantic had a decent winter by Nina standards. 

[PhiEaglesfan712]

February 20-21 looks promising: 

 

[LibertyBell]

8 hours ago, snowman19 said:

It’s do or die time. We have a limited window starting next week and into the following week to do something snow wise with the high latitude (-AO/-NAO) blocking we get. There is growing evidence that by the time we get to the beginning of March, all the blocking breaks down, MJO forcing goes back to the IO and Maritime Continent and the SPV strengthens substantially…
 

 

 

 

 

 

 

 

 

right our window to get to average snowfall for the season is February 17-28.

[LibertyBell]

4 hours ago, PhiEaglesfan712 said:

February 20-21 looks promising: 

 

we'll be lucky to get half this amount between now and the end of February lol

[snowman19]

5 minutes ago, LibertyBell said:

we'll be lucky to get half this amount between now and the end of February lol

That map is complete asinine garbage

[snowman19]

Massive fail. After all the non stop, bombastic hype for close to 2 weeks (from BAMWX, Joe Bastardi, Eric Webb and a few others) about a coming massive SSWE along with a split of the SPV for mid-February, some even invoking February, 2018 as an analog for it. Total flop, bust a rama for the ages

[GaWx]

39 minutes ago, snowman19 said:

Massive fail. After all the non stop, bombastic hype for close to 2 weeks (from BAMWX, Joe Bastardi, Eric Webb and a few others) about a coming massive SSWE along with a split of the SPV for mid-February, some even invoking February, 2018 as an analog for it. Total flop, bust a rama for the ages

 

 To their credit, the GEFS and EPS means never came that close to a 60N 10 mb wind reversal. The Euro Weeklies dropped several days in a row and got to as low as +15 on Feb 15th (Feb 2nd run) but that was it. Then it quickly headed back up. Several GFS ops had a major SSW and that in combo with the EPS falling to +15 and realizing that the GFS twice lead the way the prior 2 winters along with Joe D’Aleo’s study showing a high correlation of high solar/W QBO got me thinking there was a decent chance.

 Did Jim Hughes rule out a mid Feb major SSW two weeks ago? If so, kudos to him. But if not he’s just stating what’s obvious now.

[snowman19]

6 hours ago, GaWx said:

 To their credit, the GEFS and EPS means never came that close to a 60N 10 mb wind reversal. The Euro Weeklies dropped several days in a row and got to as low as +15 on Feb 15th (Feb 2nd run) but that was it. Then it quickly headed back up. Several GFS ops had a major SSW and that in combo with the EPS falling to +15 and realizing that the GFS twice lead the way the prior 2 winters along with Joe D’Aleo’s study showing a high correlation of high solar/W QBO got me thinking there was a decent chance.

 Did Jim Hughes rule out a mid Feb major SSW two weeks ago? If so, kudos to him. But if not he’s just stating what’s obvious now.

Joe the clown Bastardi has completely ignored his latest epic bust and has already started to hype a major SSWE in March. He has no shame. Even if we were to see a SSW in March it’s too little, too late, it’ll be spring before any effects are even felt with the lag. Game over, say goodnight and goodbye, adios, fat lady will have sung, bring down the curtain, stick a fork it winter 24-25 at that point, a former winter

[PhiEaglesfan712]

If this pans out, we might rival winter temp departures of 2013-14 and 2014-15 in some places in the Northeast/Mid-Atlantic.

[bluewave]

Interesting split with the EPAC going into El Niño mode while the La Niña remains entrenched in the CPAC.

 

[LibertyBell]

2 hours ago, PhiEaglesfan712 said:

If this pans out, we might rival winter temp departures of 2013-14 and 2014-15 in some places in the Northeast/Mid-Atlantic.

we went into a suppressive pattern in late winter 2014 so this might turn out correct

[GaWx]

3 hours ago, PhiEaglesfan712 said:

If this pans out, we might rival winter temp departures of 2013-14 and 2014-15 in some places in the Northeast/Mid-Atlantic.

At NYC using Don’s projected 3.2 BN for Feb, it would rival the 2009-10 DJF average. But it doesn’t appear to me it would be quite as cold as 2014-5, 2013-4, and 2010-1 (using same base). @donsutherland1what do you think?

[GaWx]

 Below is the latest GEFS +PNA prediction. If it were to verify closely, DJF of 2024-5 would end up at or very near the highest +PNA on record (back at least to 1949-50):

 If the above were to verify closely, I’d project Feb PNA of ~+1.60, which would mean DJF PNA of +1.45! Current highest on record are these:

1976-7: +1.43

2015-6: +1.43

2002-3: +1.20

1969-70: +1.14

1982-3: +1.08

1960-1: +1.07

1963-4: +1.06

1986-7: +1.01

 Note that all of these were El Niño except the ENSO neutral 1960-1. The highest PNA on record currently for La Niña is only +0.86 (2000-01). So, that will be obliterated.

 

https://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/norm.pna.monthly.b5001.current.ascii.table

[donsutherland1]

2 hours ago, GaWx said:

At NYC using Don’s projected 3.2 BN for Feb, it would rival the 2009-10 DJF average. But it doesn’t appear to me it would be quite as cold as 2014-5, 2013-4, and 2010-1 (using same base). @donsutherland1what do you think?

If the numbers verify, Winter 2024-25 would have a seasonal mean temperature of 34.1° in New York City. That would be the coldest winter since 2014-15, which had a mean temperature of 31.7°.