tron777 wrote: ↑Wed Dec 07, 2022 11:29 am
Wow... 12Z GFS is even slower then the 6Z with that system for next week. If correct, we get wet on Wed and Thurs both. The cold air is delayed until Thurs night or Friday with backlash flurries and snow showers possible.
The storm train is on the move the last part of that run! All kinds of energy heading along the southern part of the country with the cold air kind of entrenched in the Midwest.
The blocking across the top being shown on the 12z GFS is very extreme! Did you see that monster ridge over AK keep reloading? WOW... it was a thing of beauty. Can we get these looks to hold is the ultimate question. I will say one thing, with the pattern becoming very extreme looking and amplified, the OP models especially are going to have some fun looking solutions over the next week or two.
tron777 wrote: ↑Wed Dec 07, 2022 11:29 am
Wow... 12Z GFS is even slower then the 6Z with that system for next week. If correct, we get wet on Wed and Thurs both. The cold air is delayed until Thurs night or Friday with backlash flurries and snow showers possible.
Good Afternoon Les and just got back home and looked at the gfs and cmc as the euro is running at the moment and love what I see. I believe the models are trying to come together and you mentioned how the system looks even slower for next week and that is not a problem. This tells me that the NAO is going to be really negative next week with that setup. Getting a big slow moving storm is wonderful and especially since it looks like to me the cold air itself will have no problem coming in after this system. Then the models will have problems with a southern system and many times will not even show it until about 2-3 days before. I believe one will form and my reasoning is just what I have seen over so many years of trying to forecast winters in this area. Not sure why this happens with the models but it seems to happen at least once every winter and sometimes more than once. Will this form next Friday,Saturday or Sunday is a good question and with the first system slowing down I would expect next weekend the 17th or 18th when this system forms. Before that happens we can get some snow showers or flurries as cold air dives in here but nothing that should cause any problems.
Saying all of that what is the fly in the ointment that kills this decent pattern. We have been talking about the pna and yes it needs to go at least neutral or slightly positive next week. We need that ridging up into Alaska to take hold on models have been going back and forth on this outcome.
tron777 wrote: ↑Wed Dec 07, 2022 11:29 am
Wow... 12Z GFS is even slower then the 6Z with that system for next week. If correct, we get wet on Wed and Thurs both. The cold air is delayed until Thurs night or Friday with backlash flurries and snow showers possible.
The storm train is on the move the last part of that run! All kinds of energy heading along the southern part of the country with the cold air kind of entrenched in the Midwest.
The blocking across the top being shown on the 12z GFS is very extreme! Did you see that monster ridge over AK keep reloading? WOW... it was a thing of beauty. Can we get these looks to hold is the ultimate question. I will say one thing, with the pattern becoming very extreme looking and amplified, the OP models especially are going to have some fun looking solutions over the next week or two.
As Brian Goode stated in his video. A pattern like this can cause snowfall to pop up quickly on the models without much advance warning. I wouldn't be surprised if we see that with such an extreme pattern if it truly does develop.
tron777 wrote: ↑Wed Dec 07, 2022 11:29 am
Wow... 12Z GFS is even slower then the 6Z with that system for next week. If correct, we get wet on Wed and Thurs both. The cold air is delayed until Thurs night or Friday with backlash flurries and snow showers possible.
The storm train is on the move the last part of that run! All kinds of energy heading along the southern part of the country with the cold air kind of entrenched in the Midwest.
The blocking across the top being shown on the 12z GFS is very extreme! Did you see that monster ridge over AK keep reloading? WOW... it was a thing of beauty. Can we get these looks to hold is the ultimate question. I will say one thing, with the pattern becoming very extreme looking and amplified, the OP models especially are going to have some fun looking solutions over the next week or two.
As Brian Goode stated in his video. A pattern like this can cause snowfall to pop up quickly on the models without much advance warning. I wouldn't be surprised if we see that with such an extreme pattern if it truly does develop.
I agree Doug and with such a wild pattern setting up we get some great fantasy storms as well but you must look at those for several days to see if the current pattern works for that kind of storm. We have one big storm next week which makes perfect sense but do we get another one after and that is something like you mentioned may not show up this far out.
Tim / Doug... great posts by the both of you! We can get a -PNA to work in conjunction with a -EPO / -AO / -NAO as long as the PNA isn't very negative. I mean last December the PNA was so negative it overwhelmed everything else that was going on. This time around, the PNA has been negative yes and it's still in charge of our pattern across the US this week and going into next week. A more neutral PNA would be helpful in keeping the SE ridge a little more flatter. Right now, the NAO block is so intense that it's hooking up with the SE ridge. Yes! The SE Ridge and NAO Block (which is a ridge too) are hooking up so thus, the mild pattern. The NAO will remain negative in time, but it won't be so damn intense which is a good thing. That way once the Pacific State changes, the SE Ridge will be impacted as well which we all want. I don't want it to completely disappear then you're looking at Nor Easters and we are cold and dry on the backside of these troughs.
We have a -PNA still even on the longer term 12Z OP GFS but look at it's position and look at the SE ridge's position. That's what I want to see right there for big dog potential. Anyway... I am liking the modeling today myself! The 12Z GEFS looks like the OP run and to me, that's a good thing! We haven't seen the OP and Ensemble agree very much as of late.
12Z Euro is about done and it did not slow way down like the GFS did today. The Euro is similar to the overnight run with the front coming thru Thurs morning so we'd see falling temps on Thurs with back lash snow showers on Friday of next week. This is more in line with my thinking attm. We shall see as there is a lot of time for the timing on this system to change. The bottom line though is that every piece of guidance out there continues to show this system as the one to bring about the pattern change we've all been waiting for. The results, naturally are TBD.
tron777 wrote: ↑Wed Dec 07, 2022 2:02 pm
12Z Euro is about done and it did not slow way down like the GFS did today. The Euro is similar to the overnight run with the front coming thru Thurs morning so we'd see falling temps on Thurs with back lash snow showers on Friday of next week. This is more in line with my thinking attm. We shall see as there is a lot of time for the timing on this system to change. The bottom line though is that every piece of guidance out there continues to show this system as the one to bring about the pattern change we've all been waiting for. The results, naturally are TBD.
The Euro is fine as well so all 3 major models are somewhat similar until we get to day 8-10 which is expected and much of that is dealing with how negative the NAO is at that time. Again the timing will change some I believe and they slowed down quite a bit today with next weeks system and it may be correct but would have in here about 12 hours earlier. Of course how much rain do we get between today and the pattern change. No doubt we are coming out of the short term drought and water tables should be in good shape. Sunshine and how much do we see over the next 7 days and my guess the best shot is before the stronger system takes hold Tuesday or Wednesday. I would love to have a day or so where I can finish a few leftover things outside but they are not really important but something I would like to do before it gets cold.
As you can see, the pattern we are going into is now being agreed upon by most Ensemble Guidance as well as some of the Operational models. It appears that we'll have a nice trough NE of Hawaii which really pumps up the ridging towards Alaska (-EPO) The blocking across the top does link up. (-AO and -NAO) The parade of storms will continue thanks to the -PNA. Troughs are forced underneath the block. Now, if a storm gets cranked up too quickly, then you can still get it to cut sometimes. However, should the EPO be very negative and more east based (Eastern AK / NW Canada), such as the EPS shows (it's better with the EPO then even the GEFS from earlier) then yes..... we can have a very productive pattern with southern sliders and overrunning events. The core of the cold will be across the West and Plains and it slowly bleeds to the east and south. Lots of fun times ahead in my opinion and I think we are starting to see some agreement here as to where we are headed. Could it change? Certainly! But a combination where all 4 of the main teleconnection indices are all negative? Been a long time since we've seen a set up like this. I'm excited about the prospects and I'd roll with this pattern in December every single time.
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Great Map Les and also after you sort of get the trough established the trough can deepen from the east as well and this happens many times with a negative NAO. So yes the first trough builds in from the west which is normal but depending on other factors you can get that trough to deepen from the east.
18Z GFS offers up a different solution for next week's pattern changing system. The low occludes over the Dakotas then fills in (weakens), with a second low forming and moving up the front to our West. This second low occludes over the Arrowhead of MN. Sometime between Tues night and Thurs of next week looks to be a very wet period for us. Amounts to be determined as well as timing but I like the 1-2" range that I posted earlier.
What's interesting about that 500mb pattern is , to me the flow into the lower OV is still from the SW off the pacific, not warm pac air but modified cooled pac air which would also be loaded with moisture, hopefully.
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Bgoney wrote: ↑Wed Dec 07, 2022 5:42 pm
What's interesting about that 500mb pattern is , to me the flow into the lower OV is still from the SW off the pacific, not warm pac air but modified cooled pac air which would also be loaded with moisture, hopefully.
Exactly Bgoney, Les and I talked about this before and this southwest flow was around quite often in the 70's when we had those wonderful years. Storms were often during those years and you would get the southwest flow but that just brought in more moisture. Not saying we are going to have those kinds of winters around here because they are rare plus back then we were in a weak El Nino which is usually a good pattern for us. Going to be fun the second half of the month and lets hope the potential pans out.
tron777 wrote: ↑Wed Dec 07, 2022 5:32 pm
18Z GFS offers up a different solution for next week's pattern changing system. The low occludes over the Dakotas then fills in (weakens), with a second low forming and moving up the front to our West. This second low occludes over the Arrowhead of MN. Sometime between Tues night and Thurs of next week looks to be a very wet period for us. Amounts to be determined as well as timing but I like the 1-2" range that I posted earlier.
Les I know with a projected very negative NAO that I need to slow the systems down more than I have already.
Bgoney wrote: ↑Wed Dec 07, 2022 5:42 pm
What's interesting about that 500mb pattern is , to me the flow into the lower OV is still from the SW off the pacific, not warm pac air but modified cooled pac air which would also be loaded with moisture, hopefully.
Exactly Bgoney, Les and I talked about this before and this southwest flow was around quite often in the 70's when we had those wonderful years. Storms were often during those years and you would get the southwest flow but that just brought in more moisture. Not saying we are going to have those kinds of winters around here because they are rare plus back then we were in a weak El Nino which is usually a good pattern for us. Going to be fun the second half of the month and lets hope the potential pans out.
Here's a 500mb ,same date, map with winds if anyone wants a visual. Follow the contours for mid level flow
500wh.conus.png
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Former owner of Gut Feeling Forecast (GFF) and Doppler Infinity
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Bgoney wrote: ↑Wed Dec 07, 2022 5:42 pm
What's interesting about that 500mb pattern is , to me the flow into the lower OV is still from the SW off the pacific, not warm pac air but modified cooled pac air which would also be loaded with moisture, hopefully.
Exactly Bgoney, Les and I talked about this before and this southwest flow was around quite often in the 70's when we had those wonderful years. Storms were often during those years and you would get the southwest flow but that just brought in more moisture. Not saying we are going to have those kinds of winters around here because they are rare plus back then we were in a weak El Nino which is usually a good pattern for us. Going to be fun the second half of the month and lets hope the potential pans out.
Agreed fellas.... In some of our best winters, that was the flow we had. Nice temperature gradient patterns too. Tim's right. The pattern (should it occur) is like an El Nino. You typically get an active STJ in a Nino and a more dominant polar jet in a Nina. This is like a "hybrid Nina" of sorts and we can absolutely cash in provided that we are on the cooler side of the gradient. I mentioned overrunning events and southern sliders earlier with a look like that.
tron777 wrote: ↑Wed Dec 07, 2022 5:32 pm
18Z GFS offers up a different solution for next week's pattern changing system. The low occludes over the Dakotas then fills in (weakens), with a second low forming and moving up the front to our West. This second low occludes over the Arrowhead of MN. Sometime between Tues night and Thurs of next week looks to be a very wet period for us. Amounts to be determined as well as timing but I like the 1-2" range that I posted earlier.
Les I know with a projected very negative NAO that I need to slow the systems down more than I have already.
Tim, I'm trying to pad that into my posts. I may need to further adjust once we get closer in time, but the range I have provided should work at least for now based on the data we have available.
tron777 wrote: ↑Wed Dec 07, 2022 5:32 pm
18Z GFS offers up a different solution for next week's pattern changing system. The low occludes over the Dakotas then fills in (weakens), with a second low forming and moving up the front to our West. This second low occludes over the Arrowhead of MN. Sometime between Tues night and Thurs of next week looks to be a very wet period for us. Amounts to be determined as well as timing but I like the 1-2" range that I posted earlier.
Les I know with a projected very negative NAO that I need to slow the systems down more than I have already.
Tim, I'm trying to pad that into my posts. I may need to further adjust once we get closer in time, but the range I have provided should work at least for now based on the data we have available.
The good thing is the snow pack in Canada is still nice and with the system next week expect more snow for southern Canada plus the northern plains and some of the central plains into the upper midwest. To get cold air in here snow is not a must but it helps as the cold flows over the snow it warms much slower then if we had bare grounds across the north. Finally seeing the models show what we were expecting all along is a good sign and a relief because sometimes the pattern I see never happens. Next week the fun and games really begin and though I am not expecting much in the way of severe weather around here for the first system a good dose of rain like you predicted looks on target and then we let the cold start to flow in.
CVG is up to 0.95" of rain now event total since the weekend. Next round comes tomorrow afternoon ending Friday. Not expecting big amounts with this. I think around 0.10" to 0.25" is likely based on the data I've seen. Then, a touch of rain possible on Sat with that weak system passing thru that doesn't phase. Then we prepare for the big rain maker next week. So very active guys and I think the pattern remains active going forward. We can thank the -PNA for that. I'm ready to gamble with the new pattern. It's going to be one of those HRHR (High Risk, High Reward) type of patterns.
Good morning folks! The main topic of discussion I've seen from the overnight guidance is the tanking of the -EPO coming up down the road esp per all EPS Ensemble Members. Cold air delivery into the Lower 48 isn't going to be the problem. How far South and especially East does it get because of the -PNA trying to fight back? Remember... all 4 tellies are going to go negative for this new pattern we keep talking about. If we can see a weak -PNA and a weak -NAO along with a strong -EPO and -AO... if we can get that right balance, we'll score and score BIG! So that's what we are tracking folks in the longer term.
Before we get there it's all about the rain chances and mild weather. Still thinking our chances are light until next week. I still like the 1-2" call somewhere in that Tues - Thurs period once we get the timing nailed down. (Hope to do that by this weekend sometime). Then, we'll see how the pattern reacts once the big storm moves thru. Kind of a short and dirty post this morning but these are the items of interest on my mind.
Good Morning Les and a great post and like you mentioned we just need the right balance. Today another gloomy day as light rain should be around most of the day. May end up with .25-.30 but some folks further north may end up with under 1/10 of an inch. No big changes on the overnight models but I believe what the Euro and CMC see late next week is a strong storm on the east coast and that happens quite often with a healthy negative NAO. The gfs of course is trying show that but the bias of moving systems through too fast is showing up. Still not seeing the second system in the south central states and again I am not expecting that to show up on models until next week. So once the front comes through probably next Thursday cold air will rush in and next weekend will feel and hopefully look like winter. Once the pattern settles in I expect at least 2-3 weeks of winter like weather and that could extend further out but I will need to see what this pattern brings in terms of snow. No doubt this one of the best holiday patterns we have seen in recent years and hopefully we don't waste it on cold and dry but I believe the pattern is filled with energy so getting some decent overrunning systems imo looks very possible.
tpweather wrote: ↑Thu Dec 08, 2022 8:33 am
Good Morning Les and a great post and like you mentioned we just need the right balance. Today another gloomy day as light rain should be around most of the day. May end up with .25-.30 but some folks further north may end up with under 1/10 of an inch. No big changes on the overnight models but I believe what the Euro and CMC see late next week is a strong storm on the east coast and that happens quite often with a healthy negative NAO. The gfs of course is trying show that but the bias of moving systems through too fast is showing up. Still not seeing the second system in the south central states and again I am not expecting that to show up on models until next week. So once the front comes through probably next Thursday cold air will rush in and next weekend will feel and hopefully look like winter. Once the pattern settles in I expect at least 2-3 weeks of winter like weather and that could extend further out but I will need to see what this pattern brings in terms of snow. No doubt this one of the best holiday patterns we have seen in recent years and hopefully we don't waste it on cold and dry but I believe the pattern is filled with energy so getting some decent overrunning systems imo looks very possible.
Tim... to be honest, I don't think we have to worry about cold and dry due to the -PNA. That'll keep the storms rolling in via the STJ across S CA and across the southern US. We of course, need a perfectly timed shortwave dropping in from the polar jet from the NW for the cold air supplier. You get the right timing and balance then bang! IMO, this is what I am going to be watching. If we had a +PNA, then I would def be concerned about cold and dry. I don't think we will have that in December. Maybe later on in the winter but not early on in the game.
I did bust on the timing of the next round of rain since it's already here. I was expecting it to come in this afternoon but it arrived about 6 hours faster then I expected. That STJ means business!!!
tron777 wrote: ↑Thu Dec 08, 2022 8:50 am
I did bust on the timing of the next round of rain since it's already here. I was expecting it to come in this afternoon but it arrived about 6 hours faster then I expected. That STJ means business!!!
The STJ is moving fast and with the nao going really negative next week we have that fight of systems moving fast but the blocking is slowly them down. That is why timing on this systems is hard for us and the models to figure out. I believe with each wave that heads this way we just need to watch radar returns to see if the next system is coming in fast or slowing down.
tron777 wrote: ↑Thu Dec 08, 2022 8:50 am
I did bust on the timing of the next round of rain since it's already here. I was expecting it to come in this afternoon but it arrived about 6 hours faster then I expected. That STJ means business!!!
The STJ is moving fast and with the nao going really negative next week we have that fight of systems moving fast but the blocking is slowly them down. That is why timing on this systems is hard for us and the models to figure out. I believe with each wave that heads this way we just need to watch radar returns to see if the next system is coming in fast or slowing down.
I will say one thing, with the pattern becoming very extreme looking and amplified, the OP models especially are going to have some fun looking solutions over the next week or two.
