December 2022 Weather Discussion

[dce]

The Aussies say we are in phase 4.

[snowbo]

Question: We go up to Michigan every February to snowshoe. Is the upcoming pattern going to benefit the lake effect areas in northwest Michigan?

[tron777]

The Aussies say we are in phase 4.

Thank you Doug for posting this. I have not checked it in a couple of days. No model that I have seen (just checked) has the MJO doing this. All models either keep it in the neutral circle or later on maybe a quick trip in Phase 1 or 2. The thing is... will the MJO have any influence on the pattern at all since the blocking is so intense on top? The blocking "should" override that one would think?

[tron777]

Question: We go up to Michigan every February to snowshoe. Is the upcoming pattern going to benefit the lake effect areas in northwest Michigan?

If the flow is NW it absolutely will. The main storm track should be south of the UP for a lot of synoptic systems in my opinion so you would need NW flow for Lake Effect in the UP to occur. A tad early for high confidence on this but if you want to talk potential, then yes it is there esp since we are dealing with true arctic air pouring into the country over the next few weeks.

[Bgoney]

The CPC had a wonderful write up this afternoon discussing their thinking on the pattern for Weeks 3 and 4 (12/14 thru 1/6/23) This is a great read and they talk about many of the things we've been tracking on our forum too over the last few weeks. They discuss the teleconnections and the MJO (just like we do) Hopefully everyone who reads this post clicks on the link below and takes the time to read this and digest it. It's a really nice write up!

https://www.cpc.ncep.noaa.gov/products/ ... ions/WK34/

Dang that was impressive , I like that guy's style . Usually the CPC hates to go on and on about anything cold, but this guy wasn't having any of that, kudos to him

[dce]

The Aussies say we are in phase 4.

Thank you Doug for posting this. I have not checked it in a couple of days. No model that I have seen (just checked) has the MJO doing this. All models either keep it in the neutral circle or later on maybe a quick trip in Phase 1 or 2. The thing is... will the MJO have any influence on the pattern at all since the blocking is so intense on top? The blocking "should" override that one would think?

Every other model has it in the circle of death. I'm beginning to think the Australian model is always off. If they are correct then every other model is always off. I tend to lean toward the Aussies are off in their plotting, but I really don't know.

[MVWxObserver]

Picked up .20" from Fri.

[tpweather]

The Aussies say we are in phase 4.

I have been watching this since the start of November and glad somebody brought this up. It seems to me that the weather and this tool we use is not matching up this season. I understand there is always a time lag and again this is only a tool not what is happening. Over the years the Aussie mjo has been decent and though not perfect it has come in handy sometimes especially longer term. This season and I am talking since the start of November it seems to be about 5-7 days behind of what is going on with the weather. Usually that has been more like 1-3 days. Though not discounting this I have put little weight into my forecasts until I feel comfortable that the model is correct. Maybe like Les mentioned this is not controlling the weather and since we are seeing some serious blocking to the north does this overtake the mjo to where the mjo has little to no influence at all with the weather in the USA. Not sure but just a few thoughts on what may or may not be happening.

[tpweather]

Good Morning and really nothing changed on the overnight models. Still everything seems onboard for the pattern change. A couple of things to discuss and the first is how much rain do we get later Tuesday into Wednesday. I have been going with the lighter end around .5-1. I can see though if the front stalls out where that total could go higher but going to give it a few days before moving my totals up. Then the colder air works in Thursday through the weekend. Should see temps in the mid-upper 30's during the day and probably mid-upper 20's at night as I expect clouds around with some snow showers and flurries at times. After that I expect a much stronger push of cold air in here starting around the 19th. Will this be brought by another storm or just the cold moving further south as it takes hold. I still believe another system will form somewhere over New Mexico or Colorado and head east. Will this stay to the south or do we see a more northeast movement of this system. I know hard to tell since the models probably don't have it figured in yet but by the middle of next week and you get within the 5 day period I expect this to show up and then we can figure out if this will give us some snow.

[tron777]

The CPC had a wonderful write up this afternoon discussing their thinking on the pattern for Weeks 3 and 4 (12/14 thru 1/6/23) This is a great read and they talk about many of the things we've been tracking on our forum too over the last few weeks. They discuss the teleconnections and the MJO (just like we do) Hopefully everyone who reads this post clicks on the link below and takes the time to read this and digest it. It's a really nice write up!

https://www.cpc.ncep.noaa.gov/products/ ... ions/WK34/

Dang that was impressive , I like that guy's style . Usually the CPC hates to go on and on about anything cold, but this guy wasn't having any of that, kudos to him

They do heavily weight their forecasts on ENSO but as you said, it was nice to see them covering other topics that drive our weather also. Hope that guy continues to do the Week 3/4 write up's each Friday afternoon at 3pm. Hope to remember to check it again.

[tron777]

The Aussies say we are in phase 4.

Thank you Doug for posting this. I have not checked it in a couple of days. No model that I have seen (just checked) has the MJO doing this. All models either keep it in the neutral circle or later on maybe a quick trip in Phase 1 or 2. The thing is... will the MJO have any influence on the pattern at all since the blocking is so intense on top? The blocking "should" override that one would think?

Every other model has it in the circle of death. I'm beginning to think the Australian model is always off. If they are correct then every other model is always off. I tend to lean toward the Aussies are off in their plotting, but I really don't know.

I typically favor the Aussie Model myself, but in this case none of them are correct. Even Kyle MacRitchie's experimental MJO model has been awful.

[tron777]

The Aussies say we are in phase 4.

I have been watching this since the start of November and glad somebody brought this up. It seems to me that the weather and this tool we use is not matching up this season. I understand there is always a time lag and again this is only a tool not what is happening. Over the years the Aussie mjo has been decent and though not perfect it has come in handy sometimes especially longer term. This season and I am talking since the start of November it seems to be about 5-7 days behind of what is going on with the weather. Usually that has been more like 1-3 days. Though not discounting this I have put little weight into my forecasts until I feel comfortable that the model is correct. Maybe like Les mentioned this is not controlling the weather and since we are seeing some serious blocking to the north does this overtake the mjo to where the mjo has little to no influence at all with the weather in the USA. Not sure but just a few thoughts on what may or may not be happening.

That is exactly what I think Tim. The MJO in my opinion did help get us that colder pattern back in November. For the next cold spell that begins Friday of next week... other factors have been at work to produce this pattern with the MJO not being one of them. What I believe happened was a splitting of the PV (remember it's been weak all along this season) and we got lucky this time as the coldest air is here and not in Siberia. We've been seeing tendencies for blocking all year long, even over the summer. I've been noticing all of this playing out so it makes sense to me why we are continuing to see this blocking despite a Nina background state. I think the MJO not driving the pattern right now is a good thing or else we would never be able to get this awesome blocking pattern to set up like it appears to be doing. Furthermore, it looks to be fairly sustainable too! Once this block gets rolling, models are going to want to rush breaking it down. As a matter of fact, I think after the New Year, the blocking reloads and more fun to be had. As we've discussed Tim... a 3-4 week period of potential is coming.

[tron777]

Good Morning and really nothing changed on the overnight models. Still everything seems onboard for the pattern change. A couple of things to discuss and the first is how much rain do we get later Tuesday into Wednesday. I have been going with the lighter end around .5-1. I can see though if the front stalls out where that total could go higher but going to give it a few days before moving my totals up. Then the colder air works in Thursday through the weekend. Should see temps in the mid-upper 30's during the day and probably mid-upper 20's at night as I expect clouds around with some snow showers and flurries at times. After that I expect a much stronger push of cold air in here starting around the 19th. Will this be brought by another storm or just the cold moving further south as it takes hold. I still believe another system will form somewhere over New Mexico or Colorado and head east. Will this stay to the south or do we see a more northeast movement of this system. I know hard to tell since the models probably don't have it figured in yet but by the middle of next week and you get within the 5 day period I expect this to show up and then we can figure out if this will give us some snow.

Good morning Tim! I think your call is right on the mark for rainfall amounts on Wed. Mine is overdone. Guidance looks great showing around 3/4" at CVG give or take so that 0.50" to 1" call is money. You've got my support, as I am abandoning my higher call. I think you are dead on with the severe storms robbing us of some moisture and due to the fact that the low is occluding, the heavier totals will be west of us and lighter as one goes east. Then we get the back lash snow showers Fri maybe into Sat. No issues of course are expected.

So now what? What happens next? Give me a bit as I've got some things I want to write up in a separate post.

[tpweather]

Good Morning Les and I agree 100p/c as we know this is a big blocking pattern setting up and models were trying to rush this in but I would not give up on the 16th or so for us to really start getting into the that pattern locally. 3-4 weeks in the mid-Dec - early and middle Jan is all we can ask for and if we get unlucky with snow then it was not meant to be this season. Personally I believe during this 3-4 week period we have several systems move in here and hopefully we get lucky. We have seen years where Lexington gets twice as much snow as Indy and that happens depending on how the storm path finally takes shape. With this pattern I expect an overall snowy pattern for the Ohio Valley and East Coast. Predicting snow totals is one of the hardest areas to predict and the bust potential is always there but since I enjoy throwing myself out there I believe between Dec 16th and Jan 15th that 20 inches will hit CVG. Could be several 1-3 inch snow falls in that time period and hopefully 1 bigger storm to boost the totals. Getting that layer of snow on the ground and having that a couple hundred miles south of here would really help that prediction lol.

[tron777]

Good Morning Les and I agree 100p/c as we know this is a big blocking pattern setting up and models were trying to rush this in but I would not give up on the 16th or so for us to really start getting into the that pattern locally. 3-4 weeks in the mid-Dec - early and middle Jan is all we can ask for and if we get unlucky with snow then it was not meant to be this season. Personally I believe during this 3-4 week period we have several systems move in here and hopefully we get lucky. We have seen years where Lexington gets twice as much snow as Indy and that happens depending on how the storm path finally takes shape. With this pattern I expect an overall snowy pattern for the Ohio Valley and East Coast. Predicting snow totals is one of the hardest areas to predict and the bust potential is always there but since I enjoy throwing myself out there I believe between Dec 16th and Jan 15th that 20 inches will hit CVG. Could be several 1-3 inch snow falls in that time period and hopefully 1 bigger storm to boost the totals. Getting that layer of snow on the ground and having that a couple hundred miles south of here would really help that prediction lol.

I think we get lucky too and I'm not fond of how the GFS is handling the flow once the pattern changes. I will explain it shortly...

[tron777]

Okay so I don't think the GFS is seeing the PNA getting more neutral or even positive. The EPS, OP Euro, CMC, GEPS, etc.. are all showing a tanking -EPO and the PNA perhaps even becoming positive. Even the GEFS has a more neutral PNA then the Operational. Beyond Day 5, toss the GFS in the garbage can in my honest opinion. The cold is coming and the snow chances will be also with the active storm train we've talked about lining up in the Pacific. Check out the EPO and how it tanks from the Euro. Also posted are the individual EPS members on the EPO. Finally, the PNA forecast for your viewing pleasure. Fun times ahead folks...

EuroEPO.jpg

EPSEPOMembers.jpg

PNA.jpg

I think our first chance for wintry weather once the change has completed is around 12/19 - 12/21 time period. Then I believe another one to watch around Christmas itself.

[tpweather]

Les we talked quite a bit about the pna the last few weeks and imo that was the piece of the puzzle that needed to change. In most patterns I love seeing a neutral to slightly positive pna as that seems to work best for us in getting snow chances. I understand sometimes a really positive pna can help us but with the predictions of the other tellies I thought a neutral to slightly positive pna is the best shot of us getting snow.

You are correct the cold is coming and we can put that into the 99.9 percent chance of happening. Snow chances that gives us accumulations is probably in that 75p/c range which is higher than most periods around here.

So early in the season we must give the CMC the award for seeing the new pattern. Euro was a close second but at times would go off the rails. The new gfs seems to be worse than the old version. I have no ideal what is put into those updates but it seems that if a bias is shown that would be one of the items you try and correct. So far that has not happened. I understand each model does better with certain patterns but all of them should be able to correct themselves as we get closer to a new pattern. What worries me is the gfs will make a correction in the next several days and then we get those wild snow storms this model likes to throw out.

[tpweather]

Les we talked about how the cold was on this side of the earth and over the past 6 weeks that has been true except for the last week eastern Siberia has been getting colder which you would expect this time of year. Normally that would put up a red flag that the cold may be switching to the other side of the earth but this season not so much. The PV is there as always but not nearly as strong for this time of year and getting disruptions is so much easier. Also with the blocking that is predicted getting a cross-polar flow is higher than normal. When you get a strong PV and it gets disrupted you better be in the correct place for a few weeks of really cold air. Sure sooner or later we will need the cold air to build up once again but having this push in mid-Dec gives us the best chance of it lasting several weeks. We saw that first hint of blocking in the middle 10 days of November and that was nice but it was not going to last that time of year. Same is true once you get into later February and March as you can get a nice shot of cold air but only for a brief period.

One last thing this morning and we talk about overriding precip with a pattern like this and does this mean we are talking about ice. If the pattern sets up the way I expect the answer is not really as we would be deep enough in the cold air that snow is more likely. This could be a bigger problem though in the Tn Valley and upper gulf states.

[tron777]

Les we talked about how the cold was on this side of the earth and over the past 6 weeks that has been true except for the last week eastern Siberia has been getting colder which you would expect this time of year. Normally that would put up a red flag that the cold may be switching to the other side of the earth but this season not so much. The PV is there as always but not nearly as strong for this time of year and getting disruptions is so much easier. Also with the blocking that is predicted getting a cross-polar flow is higher than normal. When you get a strong PV and it gets disrupted you better be in the correct place for a few weeks of really cold air. Sure sooner or later we will need the cold air to build up once again but having this push in mid-Dec gives us the best chance of it lasting several weeks. We saw that first hint of blocking in the middle 10 days of November and that was nice but it was not going to last that time of year. Same is true once you get into later February and March as you can get a nice shot of cold air but only for a brief period.

One last thing this morning and we talk about overriding precip with a pattern like this and does this mean we are talking about ice. If the pattern sets up the way I expect the answer is not really as we would be deep enough in the cold air that snow is more likely. This could be a bigger problem though in the Tn Valley and upper gulf states.

The extremely -EPO will allow for cross polar flow from Siberia to keep Canada in the ice box which is good news for Lower 48 snow lovers. All precip types will be possible with this set up with the flow trying to come in from the SW aloft but keep it NE at the surface and that is usually a nice recipe for winter storms. I think we will be seeing set up's like this in due time. As you said, as long as the cold air is deep enough, ice shouldn't be an issue but I would not rule out anything at this distance. The bottom line that we can all agree on is that the cold is coming and we'll see how the active pattern interacts with it. Should be fun based on the 500 MB pattern being shown on the Ensemble guidance.

[tron777]

A portion of the AFD from the boys this morning for those with outdoor plans this afternoon and evening...

VSBYs will improve area- wide by mid/late morning before the
arrival of /yet another/ weak system later in the daytime
period. Will probably see some patchy light rain skirt far srn
parts of the ILN FA this afternoon, with locales N of the OH Rvr
expected to remain mostly dry through the daytime.

Highs this afternoon will be right on par with what we have seen
recently, topping out in the mid 40s in the N to lower 50s S of
the OH Rvr.

By this evening, a weak frontal boundary will move in from the
W, bringing with it a narrow axis of ISO/SCT SHRA along the
eastward-advancing boundary. Expect the "best" coverage, which
will be rather limited to begin with, to evolve from W to E from
about 04z through 10z or so. Another few hundredths to around a
tenth of an inch will be possible with this feature.

Temps will be slow to drop off this evening (if they do at all)
before trending cooler in the post-frontal environment between
midnight and dawn. Lows will bottom out in the upper 30s in WC
OH to mid 40s in the lower Scioto Vly/NE KY.

[tpweather]

Gfs is catching on finally. Late to the party but still made it before things get interesting.

[tron777]

Gfs is catching on finally. Late to the party but still made it before things get interesting.

No doubt Tim! I was going to post the same thing. It's finally coming around to the Nor 'Easter solution that really was an easy call since that outcome totally fits the pattern. 1.21" of rain for Wed and Thurs per this run of the GFS.

[tpweather]

Gfs is catching on finally. Late to the party but still made it before things get interesting.

No doubt Tim! I was going to post the same thing. It's finally coming around to the Nor 'Easter solution that really was an easy call since that outcome totally fits the pattern. 1.21" of rain for Wed and Thurs per this run of the GFS.

Les you can see the STJ after we get that first push of cold still alive and well. I will start watching for another system to develop in the New Mexico area next weekend and see how it tracks. Again we will look at each system when it develops but I believe we got the pattern down.

[tron777]

Gfs is catching on finally. Late to the party but still made it before things get interesting.

No doubt Tim! I was going to post the same thing. It's finally coming around to the Nor 'Easter solution that really was an easy call since that outcome totally fits the pattern. 1.21" of rain for Wed and Thurs per this run of the GFS.

Les you can see the STJ after we get that first push of cold still alive and well. I will start watching for another system to develop in the New Mexico area next weekend and see how it tracks. Again we will look at each system when it develops but I believe we got the pattern down.

Agreed. We've got the pattern down and the timing. Now the devil will be in the details in terms of individual storms.

[tron777]

12Z Canadian continues with the most consistent look of a strong Nor' Easter and we get wrap around snow showers Fri ending on Sat. Our first possible event would be around the 20th or so which I've said a few times already. 12Z GEFS looks good with the Nor 'Easter as well. Then by the 18-19th there is energy over the SW that ejects out for our possible around the 20th system. A decent signal from the GEFS today on that.