Southern Plains winter wx thread (2009-2010)

[srainhoutx]

Anyone notice the -40 degrees in the Arctic Areas on the 00Z NAM at 60 Hours.

http://www.nco.ncep.noaa.gov/pmb/nwprod ... p_060l.gif

[iorange55]

Anyone notice the -40 degrees in the Arctic Areas on the 00Z NAM at 60 Hours.

http://www.nco.ncep.noaa.gov/pmb/nwprod ... p_060l.gif

Wow didn't notice that, I was wondering where those were. Let's take a trip up there I'll bring a few thousand pairs of jackets, and some hot cocoa.

[Ntxw]

Wouldn't it be easier to just bring it down here

[srainhoutx]

00Z's are running. The ensembles "hinted" for the first time today that we may infact see a bit of an Arctic bIntrusion as EWX mentioned. I would like to see a few more runs before biting on this new solutions as models struggle with the WPAC moisture plume and a weak Polar Vortex and extremely high heights over the North Pole. The 00Z NAM is showing some -40 degree temps in the 850mb level N of Canada which is about as low of temps I've ever seen via any guidance much less the NAM. We shall see.

http://www.nco.ncep.noaa.gov/pmb/nwprod ... loop.shtml

[Extremeweatherguy]

The front looks to be pushing toward OKC a little bit faster than expected. The 18z run of the RUC showed the front pushing through the city around midnight, but if you look at the latest mesonet obs, you can see that the wind shift and dewpoint drop is only a few counties away and should probably be on our doorstep within just a few hours.





This probably will not have a huge impact on the forecast, but it might make a minor impact. If the front arrives more quickly, then may be that means the cold air will erode a little more slowly too. If that is the case, then the OKC area might be at risk for some freezing rain showers Tuesday morning. Currently the NWS forecast is placing this risk just to our north and west (with temperatures hovering between 32-34F here in the area surrounding OKC), but if the cold air is slower to move out and temperatures are a little colder (even by just a few degrees), then we might be in store for a brief period of light icing too. It will be interesting to watch play out.

[Extremeweatherguy]

The 18z GFS is showing a minor winter weather event setting up for Oklahoma on Friday. It very well could wind up being a bigger player for the state (in terms of winter precipitation) than the midweek event will be:

http://www.nco.ncep.noaa.gov/pmb/nwprod ... n_108l.gif
http://www.nco.ncep.noaa.gov/pmb/nwprod ... n_114l.gif
http://www.nco.ncep.noaa.gov/pmb/nwprod ... n_120l.gif
http://www.nco.ncep.noaa.gov/pmb/nwprod ... n_126l.gif
http://www.nco.ncep.noaa.gov/pmb/nwprod ... n_132l.gif

The temperature profile is very borderline at times between snow vs. ice for Oklahoma City, so it could conceivably go either way. Might even see some light accumulations if things played out like the model is showing. Being that this is just starting to show up in the modeling though, I am not too inclined to buy into it just yet. If we can get some more model consistency tonight into tomorrow however, then it might be worth watching a little more closely.

[Ntxw]

I still think the models are underplaying the amount of cold air that will be in place. Also the midweek storm should lay a good amount of snow cover up north so any arctic air coming down would be less modified

[wx247]

This is going to be a close call here with the midweek system. I am curious to see if we get any model changes tonight or tomorrow with the track of the low.

[Extremeweatherguy]

The front is now pushing into OKC. The winds are increasing and the dewpoints are beginning to drop. The temperature right now is in the lower 40s, but should begin to fall pretty quickly.

UPDATE: Down to 27F now at 1:45am

[srainhoutx]

The front is now pushing into OKC. The winds are increasing and the dewpoints are beginning to drop. The temperature right now is in the lower 40s, but should begin to fall pretty quickly.

Good luck Extremeweatherguy. Think Southern Track.

[iorange55]

The front is now pushing into OKC. The winds are increasing and the dewpoints are beginning to drop. The temperature right now is in the lower 40s, but should begin to fall pretty quickly.

Good luck Extremeweatherguy. Think Southern Track.

Yes also think pictures and lots of reports because we'll be bored with our boring weather period down here.

[Extremeweatherguy]

The front is now pushing into OKC. The winds are increasing and the dewpoints are beginning to drop. The temperature right now is in the lower 40s, but should begin to fall pretty quickly.

Good luck Extremeweatherguy. Think Southern Track.

Yes also think pictures and lots of reports because we'll be bored with our boring weather period down here.

I doubt there will be much to report or take pictures of even up here. If we don't get lucky with a more southern storm track, then the chances for winter precipitation with the Tuesday system look slim..may be some light icing if things play out right, or a few back end snowflakes, but that's probably about it. We could still get some very strong winds though (possibly even to High Wind Warning criteria), so that might be worthy of reports/pictures if any damage is generated. I guess we'll see. I'm truthfully already starting to look towards the next system which could arrive later this week around Friday. If the latest models are right, then there could be a much better chance for some winter precipitation into central Oklahoma (and perhaps even further south) with that event.

[Ntxw]

The later storm does look quite interesting

[Ntxw]

For interests, 0z gfs tonight in lala land shows possible wintry precip from Texas all the way down to parts of Florida lol

[Extremeweatherguy]

I just took a look at the 00z GFS in more detail, and wow it is definitely going to be a very chilly week regardless of whether or not we get wintery precipitation. Check out the temperatures the model run is predicting...

OKLAHOMA CITY:

MONDAY (TODAY)
High - 36F
Low - 26F

TUESDAY
High - 53F
Low - 34F

WEDNESDAY
High - 32F
Low - 24F

THURSDAY
High - 33F
Low - 21F (GFS MOS shows 17F)

FRIDAY
High - 31F
Low - 31F

SATURDAY
High - 33F
Low - 22F

SUNDAY
High - 40F
Low - 30F

5 out of 7 days feature high temperatures that struggle to get much above freezing. That would be quite impressive! The 53F on Tuesday, IF we even make it there (the GFS MOS and NAM MOS are both colder), would be the warmest reading of the week. It is not often that you see this kind of prolonged cold around here in early December.

DALLAS:

MONDAY (TODAY)
High - 44F
Low - 41F

TUESDAY
High - 60F
Low - 45F

WEDNESDAY
High - 52F (early morning low..colder during the afternoon)
Low - 34F

THURSDAY
High - 43F
Low - 32F

FRIDAY
High - 46F
Low - 40F

SATURDAY
High - 40F
Low - 33F

SUNDAY
High - 49F
Low - 34F

Dallas, while warmer than Oklahoma City, also looks to have a chilly week if the 00z GFS is correct, with several sub-50F days and morning lows hovering near the freezing mark on 4 days. Impressive considering the average high this time of year is in the upper 50s with an average low in the upper 30s.

[Ntxw]

chilly stuff I would bet those are conservative numbers based on how cold it is up north

[Extremeweatherguy]

The Norman NWS is not forecasting anything even close to what the 00z GFS showed for late this week. Their latest forecast is calling for high temperatures well into the 40s on Friday and Saturday with just plain old rain showers around.

It's worth noting that the 6z GFS has trended a little warmer - so it is very possible that their warmer-looking forecast will be correct.

[vbhoutex]

For interests, 0z gfs tonight in lala land shows possible wintry precip from Texas all the way down to parts of Florida lol

The question is, is this a hint of things to come or is it truly lala land? We have been having hints this may be coming in some earlier runs. Now we watch to see if it is an anomaly or a trend.

[Extremeweatherguy]

One thing I noticed this morning is that all of the major models are showing a big buildup of arctic air into SW Canada by the weekend. The models then differ on whether or not to bring the airmass full blast down into the USA, but based on similar setups in the past, I suspect that it will at least try. Both the 00z ECMWF and CMC show the cold arctic air making it deep into the southern plains by early next week, while the 00z GFS holds the airmass up in Canada and fizzles it out before ever coming south.

[Portastorm]

Normally I would be dismissive of the GFS in winter time but so far, the model has done quite well I think. The last two winter storms that have rolled through Texas have been progged semi-accurately by the GFS and done so well out in the future (like 240 hours).

The old adage of the GFS doing well in the very long range, losing storms in the middle range, and picking up on them 5-6 days out may still hold. Who knows.