GaWx

32 minutes ago, wncsnow said:

Another worry I have is the lack of a southern jet showing up in tne long range. A lot of the models and ensembles are going very dry for the rest of this month. 

 

26 minutes ago, NorthHillsWx said:

The lack of a southern jet is a semi-permanent feature that’s developed through the summer. Models looked like that was flipping coming into the month but nothing has changed. Until we get something coming from the southern stream the ripping northern and pac jet is going to kill us regardless of what cold is available. The ongoing drought is all you need to know about our southern stream energy through the fall. That’s going to be the biggest fail mechanism this winter I’m sure of it

 As we all know, La Niña favors a weaker than average southern jet and we’re solidly into La Niña (per the MEI/RONI). So, this is totally expected based on ENSO. I wouldn’t be surprised if it averages weaker than normal the rest of the winter. That’s the best bet. But as is normal, there are usually short periods of increased S jet from time to time even in La Niña just like there are usually short periods of weak S jet in El Nino.

1 hour ago, Terpeast said:

I didn’t think this was totally unexpected. What would have been a surprise is a much longer stay in phase 8. I’ve been watching the MJO a lot lately, and the little rmm “loop” told us that some of the forcing would be pulled back from 8 to 6, resetting the 6>7>8 progression. Hollmovers showed this pretty clearly. I think we will see another incursion into 8 by years end into january. This may actually be part of a long term shift of the standing wave from 4-6 to 7-8, which will take a while but we may actually be seeing this play out. 

I meant unexpected with regard to the main model MJO projections we follow. None of them on any day’s run had it going into 6 though it likely will leave quickly.

 There’s been an ~3 day lag time in getting the official MJO phase/amp. As it turns out, the initial phase 8 lasted only 5 days (12/3-7) as it went into phase 6 on 12/8 (per 1st image), which was totally unexpected. I’ll keep following this closely to see if it re-enters phase 8, which I think has a very good chance but we’ll see.

 Regarding this initial phase 8 (12/3-7), here are some E half of US anomalies:

- Boston: -8

- NYC: -8

- Baltimore: -7

- RDU: -8

- Atlanta: -7

- Birmingham: -7

- Tulsa: -7

 These are on the border of B and MB normal:
 
 Below are the average anomalies for NDJ, which I believe are in degrees F. These average anomalies were well exceeded even if these are in degrees C:

 Thus, this was a colder than average phase 8 in the E US based on these 7 cities.

Source for daily temperatures:

https://www.weather.gov/wrh/climate

Today’s Euro Weeklies, after the current cold domination ends, are similar in the big picture to yesterday with a stout -PNA and mildness dominating much of the E US, especially the further south you go, into mid Jan though Jan 12-18 is slightly cooler than yesterday. That last week’s PNA is less negative. The NE US is again near normal on most maps. Mid-Atlantic is mainly mild til the last week.

13 minutes ago, Daniel Boone said:

He may of thought those were minus marks before the numbers Larry.

 He’s been trolling AmericanWx for years. You may not be familiar with his posts.

20 minutes ago, Akeem the African Dream said:

that would be historic

 

 

 Hey troll, I didn’t say these were anywhere near historic. The record lows for 12/15 at RDU/ATL are way down at 8/11. But these are ~18 BN.

 The 12Z model consensus is coming in for Mon lows at ~20F for ATL and ~17-20F for RDU.

 It was about a week in advance when the models suddenly got colder for the period starting a few days before Thanksgiving. We’re now about a week before the progged big warmup in the E US. Just saying although I’m not saying that will likely happen again. But it’s good to stay grounded due to the inaccuracy of models more than a week out.

7 minutes ago, SouthboundYank said:

Got down to 29 again last evening in Myrtle Beach...and a 2nd morning of HEAVY frost, almost like snow! But temps rebounding nicely today compared to yesterday...we're up to 50 now with full sun and clear conditions.

It also got down to 29 at KSAV, which was a few degrees colder than the forecasted lower 30s. But it didn’t quite get down to the coldest yet this season, which is the incredible 28 of Nov 11th.

 Per yesterday’s Euro Weeklies, it’s overall looking to average mild from the Mid-Atlantic-OH Valley-lower Midwest south for most of the 4 week long period 12/22-1/18. Could it end up verifying well? Of course, especially the earliest portion, when statistically there’s more skill. Will it? Nobody could possibly know, obviously. Notwithstanding the poor performance for the 3 weeks from just before Thanksgiving through mid Dec, the Euro Weeklies have been just good enough at foretelling general trends that they shouldn’t be ignored by any means. But could they largely end up failing, especially for the Jan portion? Obviously they could.

2 hours ago, BooneWX said:

File this away as well: MJO always has and always will be a vastly overrated teleconnection. We’ll firmly be in 8 for these 70° days. 

1. No teleconnection even comes close to guaranteeing anything. Anyone who says it does is overrating it. But most have notable tendencies that make them helpful for forecasting. They’re useful tools, including the MJO, but they’re not crystal balls as the atmosphere is much too complicated for any one index to be reliable. I’d argue the MJO is about as good a tool as any of them, but like any tool it needs to be used correctly.

2. I recently did an analysis of 3+ day long Dec phase 8 at RDU and found a whopping 78% of them to have been colder than normal:

# of periods: MB 5 (22%), B 13 (57%), NN 0 (0%), A 2 (9%), MA 3 (13%)

 So, there have been nearly 4 times as many B/MB periods as A/MA periods at RDU for Dec phase 8 periods lasting at least 3 days.

3. Regardless, of what may come and in what phase, what about prior to that period? The period 12/3-16, most of which is forecasted to be in phase 8, is forecasted to end up with all colder than normal days at RDU and in much of the SE and to be at least in the top 5 cold for that period of the last 50 years! That would be 90 percentile cold.

4. I plan to average out the temperature anomalies for whatever days end up in phase 8 later this month.

3 hours ago, Met1985 said:

Heavy frost with a low I believe of 30 degrees here in North Charleston.  Not something you see often down in the low country. 

 Thanks. Our areas had a freezing fog advisory late last night, which I believe is quite rare:

309 AM EST WED DEC 10 2025  

..PATCHY FREEZING FOG THIS MORNING  

AREA OBSERVATIONS, SATELLITE IMAGERY, AND WEB CAMS INDICATE THAT  
PATCHY DENSE FOG IS IMPACTING PORTIONS OF SOUTHEAST GEORGIA AND  
SOUTHEAST SOUTH CAROLINA EARLY THIS MORNING. MOST OF THE PATCHY  
FOG IS SHALLOW, BUT IS PRODUCING VISIBILITIES OF A QUARTER OF A  
MILE OR LESS IN ISOLATED AREAS. MUCH OF THE FOG IS FORMING AS  
STEAM FOG NEAR WATERWAYS INCLUDING RIVERS, STREAMS, TIDAL CREEKS,  
AND MARSHES.  

TEMPERATURES ACROSS THE AREA HAVE FALLEN BELOW FREEZING AND INTO THE  
UPPER 20S IN MANY LOCATIONS. FREEZING FOG WILL OCCUR, EVEN  
PRODUCING LIGHT RIME ICE ON ELEVATED AND EXPOSED SURFACES. WHILE  
LOW VISIBILITIES COULD IMPACT TRAVEL, ESPECIALLY WHERE  
VISIBILITIES CHANGE SIGNIFICANTLY OVER SHORT DISTANCES, RIME ICE  
FROM FREEZING FOG IS NOT EXPECTED TO PRODUCE ANY IMPACT ON TRAVEL  
CONDITIONS.  

TEMPERATURES WILL RISE ABOVE FREEZING, AND ANY LINGERING FOG WILL  
DISSIPATE, BETWEEN 8 AND 9 AM THIS MORNING.  

PRECAUTIONARY/PREPAREDNESS ACTIONS...  

IF DRIVING, SLOW DOWN AND LEAVE EXTRA DISTANCE AHEAD OF YOU IN  
CASE A SUDDEN STOP IS NEEDED.

 A half hour ago I finished walking at the park in 35 invigorating degrees. To sort of borrow a phrase from DT, yes, I was the only sick, twisted cold wx freak out there walking. But I was bundled up and had extra energy giving me an extra spring in my step. Winds were calm with clear skies allowing for Gainesville, FL-like ideal radiation. I could even see some cool looking steam fog over water. Dewpoints were only a couple of degrees lower.

 Today’s high was only 45, which is 20 below normal.

Today is the 9th day in a row of highs below 60 at SAV and below 50 at GSO, extending the record! Before this SAV had never even had this for Dec 1-7 going back to 1874. GSO had had a 7 day period one other time.

 Today’s Euro Weeklies for the 4 weeks Dec 22nd through Jan 18th continue to look bad (mild) especially in the SE and MidAtlantic. There’s no way to sugarcoat it. The hope is that they’re just pain wrong. But that’s just a hope:

12/22-28:

12/29-1/4:

1/5-11

1/12-18:

 There’s a college football thread for those who don’t know and are interested that could use more discussion like this:

After a big drop yesterday of 7%, natural gas prices are again sharply lower today (down 5% for a 2 day total of 12%) on warmer E US prospects for at least late this month. It’s very rare for NG to drop that much in early winter with cold looking to dominate for the foreseeable future, which as we know is not at all the case after about a week of intense E US cold per model consensus. Week one’s intense cold is already built into the price.

 It’s usually changes in prospects for week 2 into early week 3 that drive daily changes in NG prices. That’s because week one is normally already priced in and typically doesn’t jump around too much. And beyond early week 3 is usually too far out in fantasyland/too little forecasting skill that far out to have too much impact.

21 minutes ago, TheClimateChanger said:

 

1. Where’s “Star” located?

2. No index ever even comes close to guaranteeing anything. That’s nothing new to us.

3, However: The period Dec 3-17, which is prior to the days his maps are showing, is currently looking to end up much colder than normal in the majority of the E US, including a top 3-5 coldest of the last 50 years in many places. That would jibe well with phase 8’s cold E US tendency.

Per the quite fallible model consensus:

 The -WPO looks to easily be the strongest in Dec since 2013. Other strong -WPO (sub -1.00) Decembers: 2013, 2010, 2009, 2005, 1999, 1995, 1989, 1980, 1976, 1975, 1966, 1961, 1956, 1955, and 1954.

 So, Dec of 2025 has a good shot at making the top 20% strongest -WPOs.

 How was the subsequent Jan WPO for these 15?

Negative WPO Jan: 2011, 1996, 1981, 1977, 1976, 1962, 1957, and 1956 (8 of the 15)

Neutral WPO Jan: 2010, 2000, 1955

Positive WPO Jan: 2014, 2006, 1990, 1967

 So, these strong -WPO Decembers were somewhat biased toward -WPO Jan with twice as many -WPO Jans as +WPO Jans

 The current model consensus *fwiw* suggests there’s a good chance we don’t end up with a -EPO for Dec as a whole with a lean toward fairly neutral to potentially +EPO when averaged out. How often have there been strong -WPO Decs without a -EPO?

- -EPO Dec: 2013, 2009, 2005, 1989, 1980, 1976

- neutral EPO Dec: 2010, 1995, 1966, 1956, 1955

- +EPO Dec: 1999, 1975, 1961, 1954

 So, Dec EPO was pretty balanced for strong -WPO Decembers

Monthly WPO:

https://psl.noaa.gov/data/correlation/wp.data

2 minutes ago, Coach McGuirk said:

More common than you think.  We do get snowstorms in southeaster VA.  It's feast or famine.  Last year was 1 in, 2 in, 2 in, 8.5 inches.  The previous two years were nothing.  We average 8 in a year.  We could be zero or 20 inches.  Nor'easters can drop 8-12 inches on us. 

I forgot to mention that there’s a dedicated thread for today’s storm. For documentation purposes, you may also want to post your results in there:

 Today here I just got an invigorating walk in with low 40s and just enough breeze to give it a nice bite. Today’s high of only 51 (normal is 65) means that every day so far this month has had a high only in the 50s. We already had had the first time in recorded history (back to 1874) of no high reaching 60 for Dec 1-7. Now it’s also the first time for that for Dec 1-8 and tomorrow is going to make it the first time for Dec 1-9!

 Rainfall so far this month is over 2”, which is way above the normal of 0.75” for Dec 1-9. For the first time since at least Thursday we had no rain.

8 minutes ago, Coach McGuirk said:

Storm dying out, probably end up with 6 inches.  But 6 inches that came out of nowhere is fine with me. 

How often has your area received 6” or more from a single storm?

For the record regarding the main indices for today’s wintry event:

- The prior -PNA rose to the more favorable neutral PNA (-0.1)

- AO -1.9, one day after a short-term minimum of -2.2 was hit

- NAO -1.2, one day after a short-term minimum of -1.3 was hit

- MJO likely was inside the circle phase 8 (probably won’t know for sure for a couple of days)

- +EPO

- -WPO

55 minutes ago, snowman19 said:

As I’ve learned and I’m sure many others have…..They are going with persistence forecasting, which is really not advisable at all. When you do that, you are just assuming that a pattern is going to continue and models are all wrong and are just going to keep correcting to cold without any end or breaks. Persistence forecasting works until it doesn’t. Those guys are basically saying “yea, the models have been wrong so far and the pattern hasn’t broken yet, so we are just going to keep forecasting the status quo (cold) indefinitely, no matter what the forcing may do, no matter what in the long wave pattern changes and no matter what the models may show, we don’t care”. Not only unprofessional for mets, but a very bad idea and if it fails, you totally lose credibility and trust 

Good points. But if there were a clearly identified long time model bias,  adjusting for that would obviously make sense.

22 minutes ago, MJO812 said:

The questions are whether or not and, if so, how long these same model misses will continue. It isn’t black and white. Nobody knows including you and me.

Today’s Euro Weeklies for week 3+ are still lacking cold domination to return to most of the E US south of the N tier with a solid -PNA dominating through mid Jan along with no -NAO or -AO. If this verifies, it would likely be pretty mild in much of the E US and nothing like we’ve been experiencing the last 2 weeks. However, models the last 3 weeks have been too warm in the E US with too much SER and missing much of the -NAO and -AO. Also, Midwest snowcover is well above avg, there’s the potential lag effects from the 11/28/25 SSWE, and the MJO remains favorable for E US cold. Are the weeklies/models finally getting their act together or are they going to continue with the same errors? Opinions?