OK / AR / KS / MO Winter 2013-2014

[ouamber]

Rainy day today. Guess it was freezing rain this morning since the schools are closed. Springfield's forecast for this evening and tonight is a bit confusing with a mixed bag here. Looking at this morning's models, it would appear temps would be above freezing, just barely, and everything might stay as rain until the very end of the precip when it may switch to snow.

 

Edit: 12z GFS has a frontal wave with sleet and freezing rain next Friday.

 I see nothing on the 12Z GFS that makes me believe this next Arctic Blast is gonna bring us anything more than just cold.  No major snow storm that I can see, and wouldn't we be able by now to see that IF it were going to occur.  Christmas just looks cold..blah!

[JoMo]

 I see nothing on the 12Z GFS that makes me believe this next Arctic Blast is gonna bring us anything more than just cold.  No major snow storm that I can see, and wouldn't we be able by now to see that IF it were going to occur.  Christmas just looks cold..blah!

 

The sleet/freezing rain chance is there with the frontal wave. The airmass behind the front doesn't look nearly as cold as it was either. Somehow the east coast keeps cashing in though.

 

You can relive past weather experiences through Tulsa's Sig. Weather page though.

http://www.srh.noaa.gov/tsa/?n=sigwxevents

[ouamber]

LOL Jomo! Guess I will go look at the past and remember our great GHD Blizzard of 2011...still hard to believe that actually happened? Do you remember when we started seeing signals that it was gonna happen? I thought it was at least 2 weeks prior, but I could be wrong..

[NJ_Ken]

 I see nothing on the 12Z GFS that makes me believe this next Arctic Blast is gonna bring us anything more than just cold.  No major snow storm that I can see, and wouldn't we be able by now to see that IF it were going to occur.  Christmas just looks cold..blah!

 

Keep the faith.  There is plenty of time for something to develop.  It goes without saying that we can't have winter weather without cold so the Arctic front that is looking increasingly likely to pass through in a week or so is a very critical first step.  We are just going to have to be patient and let the rest unfold.  While I am still holding out reasonable hope for a decent event sometime in the 4 or 5 days leading up to Xmas, even if there is no massive storm, the fact that we will be cold opens up a multitude of possibilities for minor events that could easily make our world look and feel a lot more "like Christmas" even if we don't get buried under a huge blizzard.  Sure I want to see a foot of snow falling on Christmas Eve and/or Christmas Day, but I will gladly take an inch or two in the days before the holiday if that is all mother nature has to offer.       

[JoMo]

LOL Jomo! Guess I will go look at the past and remember our great GHD Blizzard of 2011...still hard to believe that actually happened? Do you remember when we started seeing signals that it was gonna happen? I thought it was at least 2 weeks prior, but I could be wrong..

 

I don't remember. I also forgot about the Feb 8-9th storm that added even more snow. 

[ouamber]

Basically, in a nutshell...we need the front to speed up and the precip to slow down and stop moving off so far east where we get nothing, correct?

[wildweatherman179]

Yeah, we need a true Pacific low coupled with this awesome polar air we keep getting. With the Alaskan ridge, it probably won't happen but when the ridge deteriorates we'll probably warm up. We need it to simply slide west about 200 miles or so and hang out there til march. Lol. Not too much to ask right?

[JoMo]

Springfield says they are considering upgrading the Winter Weather Advisory to a Winter Storm Warning... northeast of me, but they have 3-6" of snow at Springfield tonight and points NE with 1-3" in the Monett area. 

[The Waterboy]

Springfield says they are considering upgrading the Winter Weather Advisory to a Winter Storm Warning... northeast of me, but they have 3-6" of snow at Springfield tonight and points NE with 1-3" in the Monett area. 

It looks to me on the radar that the western back edge of the rain is just about to push through our area.  Is there another disturbance that will fire up later today/tonight?    I must have missed that part in the NWS write-ups. 

[JoMo]

12z Euro is a bit faster with the cold front and farther south with the upper low over the SW. There may be some weak overrunning frozen precip behind the cold front (front passes through entire area by Friday evening (20th). The low ejects out Saturday bringing... (probably snow).. to the area as it shears out.

 

Also of note, the cold air doesn't look as cold, continuing the trend from the previous runs.

[JoMo]

It looks to me on the radar that the western back edge of the rain is just about to push through our area.  Is there another disturbance that will fire up later today/tonight?    I must have missed that part in the NWS write-ups. 

 

Yeah, the main system is tonight, this was just like the WAA stuff out ahead of it. It's pretty weak though. 

[JoMo]

It looks like the models are doing a bit of reshuffling of the teleconnections. Not only is the AO and NAO going to be pretty strongly positive but the WPO and EPO want to go back to around neutral it looks like. It will be interesting to see the Euro ensembles later this afternoon. 

[ouamber]

It looks like the models are doing a bit of reshuffling of the teleconnections. Not only is the AO and NAO going to be pretty strongly positive but the WPO and EPO want to go back to around neutral it looks like. It will be interesting to see the Euro ensembles later this afternoon. 

 

OK Jomo, please remind me what teleconnections we want if we want to see a lot of snow in our area? -AO, -NAO, +PNA?

[beavis1729]

It looks like the models are doing a bit of reshuffling of the teleconnections. Not only is the AO and NAO going to be pretty strongly positive but the WPO and EPO want to go back to around neutral it looks like. It will be interesting to see the Euro ensembles later this afternoon. 

 

Interesting...thanks JoMo. 

 

Do you know if the massive arctic outbreak is still being shown in 6-8 days...or has it vanished?

[wildweatherman179]

12z Euro is a bit faster with the cold front and farther south with the upper low over the SW. There may be some weak overrunning frozen precip behind the cold front (front passes through entire area by Friday evening (20th). The low ejects out Saturday bringing... (probably snow).. to the area as it shears out.

Also of note, the cold air doesn't look as cold, continuing the trend from the previous runs.

If the front is not as cold/intense, would there not be a better chance that the levels of shear come down some and that more moisture could hang around than anticipated?

[JoMo]

Interesting...thanks JoMo. 

 

Do you know if the massive arctic outbreak is still being shown in 6-8 days...or has it vanished?

 

It's still there, just not as crazy cold. The 12z Euro ensembles have it cooler than the operational/control run which warms it up rather quickly. The ensembles have it colder/cooler than normal through the entire run (Morning of Dec 28th) with the coldest of the air shifting to the northern Great Lakes and northeast and warmer than normal air in SW Canada.

[westhope84]

Seems like models may be having difficulty handling the extremity of the cold air. Perhaps the coldest will hold of until just after next weekend? Regardless, I think it will be a very cold Christmas. Yes, I hope we can manage a few inches of snow, but cold is better than nothing, in my book.

[The Waterboy]

SRAIN posted this earlier in the Texas forum.  This may be helpful for us when considering exactly how cold it could be.  Sounds like we won't know until early next week when we look up into Canada/Alaska. 

 

Morning Update from Meteorologist Jeff L (Harris County Flood Control District):

 

Dec 21-26:

Upper air pattern will undergo significant amplification along the US west coast with upper level high pressure building northward deep into Alaska and possibly northern Siberia. Global forecast models show heights rising into the 2-3 standard deviations above normal in this region by the middle of next week. Additionally, the water temperatures in the northern Pacific Ocean are some of the warmest in recent decades (nearing some historical values) and this warm pool in the region south of the Gulf of Alaska tends to favor not only building high pressure in this region, but larger and stronger high pressures cells. Upper level high pressure development in this region helps to foster a strong downstream trough over Canada and the US and its intensity/depth is dependent on the intensity of the ridging over Alaska…so the stronger the Alaskan ridge the deeper the downstream US trough.

 

All of the major global forecast models show a pattern of varying degrees of building high pressure along the US west coast deep into Alaska and potentially northern Russia by the middle to end of next week. This pattern also allows the formation of intense surface high pressure cells over NW Canada promoting the development of a pool of bitter cold air as this area is currently experiencing near zero sunshine. This cold air pool has yet to fully develop and that is why forecast models are having such a hard time determining how cold it is going to get the week of Christmas.

 

The pattern will certainly favor an arctic air outbreak into the US by the weekend of the 21^st, but how cold and how long remain viable questions this morning. With model guidance now so widely available on the internet one must be cautious to avoid believing each model run and the “extreme” numbers that at times can be shown and have been shown over the past 3-4 days. The area to watch over the coming days will be northern Russia into NW Canada and eastern Alaska in the Sunday-Tuesday time period to see how cold the air mass in the source region becomes and if surface pressures build to the forecasted values being shown (1050-1060mb). Surface air temperatures in this region are already running in the -25F to -40F range this morning. This will be much of the focus for the next several days leading into Christmas week.  

[JoMo]

OK Jomo, please remind me what teleconnections we want if we want to see a lot of snow in our area? -AO, -NAO, +PNA?

 

-AO helps deliver colder air farther south. The -EPO, -WPO do the same thing. The AO is expected to remain positive to strongly positive through the end of the GFS ensemble run through Dec 29th. This results in a tight polar vortex. As long as the EPO/WPO remain negative we'll still get cold shots.... although without blocking, they will remain progressive in nature.  The EPO is currently spiking positive with the WPO still in the negative phase. The models show the EPO going back negative shortly with that shot of Arctic air.  Both the Euro/GFS and their ensembles have the WPO climbing to neutral to slightly positive on the Euro operational. Both the Euro/GFS have the EPO remaining negative after it heads back there, however, it's weakly negative.

 

If we lose the -EPO/WPO and the AO remains positive, we will warm up.  

 

PNA doesn't really matter as much here as long as it's +/-

[JoMo]

If the front is not as cold/intense, would there not be a better chance that the levels of shear come down some and that more moisture could hang around than anticipated?

 

The system gets sheared out because the northern stream is dominant and crushes it.

[ouamber]

Thanks Jomo..this helps out a lot. So many variables, it makes my head spin.

[Wx 24/7]

I really do think it is important to do like the article mentions above and focus on the big picture and not get bogged down in the minor details so far out. It is important to watch each run and look for trends, but realize the further out you go the less reliable the model can be. I mean... we can't even get consensus from run to run on these most recent storms.

[JoMo]

12z Euro Ensembles long range (D11-15) shows that the ridge over the Pacific wants to push farther east... this results in the trough being located over the Great Lakes and Northeast US for a few days. Towards the end of the run, the ridge looks to redevelop back west to southwest of Alaska again where it has been sitting. (D14-15) There does look to be a cutoff or something over Baja but it probably won't have any influence on the weather here. It's a very progressive type of pattern that will change, but there's no sign of any major warmup for a long time. 

[JoMo]

I really do think it is important to do like the article mentions above and focus on the big picture and not get bogged down in the minor details so far out. It is important to watch each run and look for trends, but realize the further out you go the less reliable the model can be. I mean... we can't even get consensus from run to run on these most recent storms.

 

Yeah, I'm just talking about the overall pattern in general and watching for any signs of a large ridge or warmer than normal temps. The minor details would be the storms/precipitation themselves which are pretty much subject to change around a great deal. There is a signal for possible frozen precip with a storm for the area next Fri/Sat. The amounts and where or if it happens is still unclear. 

 

It's important to note that we are entering the coldest part of the year in the next few weeks, so 'normal' drops to what?... 40's/20's for highs/lows in a lot of locations? As long as cold air is available to our north, and we get a storm that passes to our south, we could still see frozen precip. 

 

The main problem we have had so far is getting something other than a positive tilted trough out of the pattern. Those typically favor precip out ahead of the front, with overrunning along and behind the front if energy is still back to the west or a stronger wave develops on the front. 

[wildweatherman179]

Thanks JoMo. I appreciate these very detailed responses.

[ouamber]

Only looking at the 12Z GFS...for whatever it's worth (which is nothing lately)...the surprising thing I'm noticing is how fast the arctic front gets shunted off to the east.....That's some mighty cold air that just wants to toy with us before moving on it's way...

[wildweatherman179]

Only looking at the 12Z GFS...for whatever it's worth (which is nothing lately)...the surprising thing I'm noticing is how fast the arctic front gets shunted off to the east.....That's some mighty cold air that just wants to toy with us before moving on it's way...

Saw that also. Doesn't seem to make much sense does it.

[JoMo]

Don't quote this since I linked the images but.....I've noticed this since last year, and JB from WxBell started mentioning it and he calls the 12z and 00z GFS the "first guess" models. The 18z and 06z runs of the GFS tend to go towards whatever the 00z and 12z runs of the Euro show.  JB's guess is because the Euro has a better initialization protocol than the GFS. 

 

Looking at the 12z and 18z GFS....

 

The 12z had general channeled type vorticity across TX/OK.....

 

 

Now here's the 18z GFS for the same hour:

 

You can see a more compact system across N Mexico:

 

That is roughly what the 12z Euro shows. (not sure about timing, but same general system in the same vicinity)

 

 

That ejects out and produces precip across the area.... (18z GFS temps are warmer at this time though, and this is after hour 192 when the model truncates, or loses the better resolution)

 

[wildweatherman179]

Well, it may be too early to say, but I'm not incredibly optimistic about the next 2 weeks as far as accumulating snows go for my neighborhood. Cold without snow is just a waste. I guess I'll have to hope for post Christmas and January for more snow.

[JoMo]

Only looking at the 12Z GFS...for whatever it's worth (which is nothing lately)...the surprising thing I'm noticing is how fast the arctic front gets shunted off to the east.....That's some mighty cold air that just wants to toy with us before moving on it's way...

 

Yeah, for some reason, each run has been getting warmer. I don't know what that's all about.