December Weather Discussion. Will We See Rain?

[redneckweather]

I love your enthusiasm srain (keep it up) but man, as stated above, this is a very poor setup for us to get snow out of. The cold air doesn't even look to be there.

[wxman57]

18z GFS Ensembles:
http://raleighwx.americanwx.com/models/ ... p12144.gif

Sorry for my "amateur " ability to read models but that looks good for us right?

Not really. Look at where the low center is on that ensembles run - way off in the NE Gulf. Now look at the pressure across Houston - 1024+ mb. That's quite high pressure. We wouldn't be getting any precip at that time. Still looks like just cold and dry next week. There probably won't be enough moisture present for precip by the time any upper-air feature moves by. And if any precip did fall out of the mid level deck, then it would most likely evaporate before reaching the ground.

[srainhoutx]

The 00Z output has started. Have fun night crew...oh, and it was -22 in Whitehorse a bit earlier...Celsius...

[TexasMetBlake]

Try -36 F!!!

[Andrew]

00z GFS is a lot colder and soooo close to some winter percip:

[helloitsb]

00z GFS is a lot colder and soooo close to some winter percip:

http://www.nco.ncep.noaa.gov/pmb/nwprod ... p_138l.gif

http://www.nco.ncep.noaa.gov/pmb/nwprod ... p_144l.gif

So close but still so far

[msanwxfan]

The 00z GFS is bit colder and has that trof pull a bit of that energy from that disturbance that develops in sw texas GOM. It shows a trace of rain while temperatures are plummeting to freezing. But with a 1024 high, whatever rain does fall will likely evap as wxman has said, it just depends how much precipitable rain falls and when . The gfs is giving this event more fun" for folks. stay tune.

[Andrew]

The 00z GFS is bit colder and has that trof pull a bit of that energy from that disturbance that develops in sw texas GOM. It shows a trace of rain while temperatures are plummeting to freezing. But with a 1024 high, whatever rain does fall will likely evap as wxman has said, it just depends how much precipitable rain falls and when . The gfs is giving this event more fun" for folks. stay tune.

[sambucol]

What kind of high and low temps will this front bring to our area?

[Andrew]

What kind of high and low temps will this front bring to our area?

I am going to post a meteogram soon but lows will most likely be below freezing with highs dependent on how much cloud cover.

[Andrew]

Here you go:

[Mr. T]

Man, things just aren't phased quite right... If that Pacific system was moving into our area just a bit faster it could possibly phase with that trough over the Great Lakes and allow for some fun to happen. So close

As it stands, we probably have a few nights in the 20s coming up for next week.

What a freaking tease that Euro run was a couple of nights ago... I've been too busy with work stuff to comment on things, but that just wasn't right, man

[Andrew]

Man, things just aren't phased quite right... If that Pacific system was moving into our area just a bit faster it could possibly phase with that trough over the Great Lakes and allow for some fun to happen. So close

As it stands, we probably have a few nights in the 20s coming up for next week.

What a freaking tease that Euro run was a couple of nights ago... I've been too busy with work stuff to comment on things, but that just wasn't right, man

Well we are still 6-7 days out so don't loose all hope.

[srainhoutx]

The Canadian (also the Euro with less moisture) is slower and a bit more moisture, but still would bring some 'hope'...oh, and the Euro at day ten says we'll repeat this again, but I won't even bother posting that chart.

12022010 00Z CMC f144.gif

12022010 00Z Euro f144.gif

[biggerbyte]

Norman, in his iPhone weather webcast, says that we are in for an extended period of cold this time, with a possibilty of winter precip. We'll see about that. Only a couple more days before we'll know for sure.... One thing is for sure. The models do not know yet either....

[wxman57]

6Z GFS is colder than 00Z, but not a trace of precip through 192 hrs. It does appear unlikely that the passing disturbance will have much moisture to work with.



Now, sometimes a passing upper-level low can drop precip from higher-based clouds. This precip often starts out as snow. The Euro and Canadian have an upper-level feature tracking across SE TX on Wednesday morning (GFS, too). But the problem that I see is that Tuesday's front may have scoured out all the moisture across Texas. It looks like there won't be enough moisture for the upper low to produce many clouds, much less any precipitation (according to the GFS). Could be the GFS is wrong and there may at least be some mid-level moisture (700mb-10,000ft) to produce some high-based snow. But the lower levels will likely be so dry that anything falling from way up there will likely evaporate on the way down.



Let's take a look at the longer range, as forecast by the 06Z GFS. Nothing to indicate any colder air coming down beyond next Tue-Wed. Now keep in mind that the "HIGH" temps on the graphic below are not that - they're 6PM CST temps. It's DARK at 6pm and the temps are falling fast. For the afternoon high (3 hrs earlier), you need to add a good 5-7 deg. So lows in the 40s-50s and highs in the 70s for the week leading to Christmas is what the GFS forecasts:

[srainhoutx]

I'm glad you posted the Skew chart wxman57. Those are important to watch as we get closer. What I do see is the potential for an active period of several Upper Air disturbance riding along the trough into the end of next week and that is depicted in the 240 hour Euro.

[wxman57]

By the way, that "Twister" site does soundings, too. Just select the model you want (GFS or NAM) and then the time from one of the green boxes on the left and mouse over the map. Wherever you click you can generate a sounding. Use the +/- navigation to move forward or backward in time.

http://www.twisterdata.com/

The ARL site that I use for the meteograms also does nice soundings. You can even generate a sounding loop there:

http://ready.arl.noaa.gov/READYcmet.php

Here, I made a sounding loop starting at 120hrs and going out 48 hrs on the ARL site. It's for IAH. Note how the air dries out aloft once the cold front arrives:

http://ready.arl.noaa.gov/readyout/3998 ... f_anim.gif

[srainhoutx]

Looking at the 06Z GFS ensemble means, there is some spread between hour 126 and 138. Does it mean anything important? Probably not in the long run...

http://raleighwx.americanwx.com/models/ ... zf126.html

[srainhoutx]

Not to get too far ahead of ourselves, but wow...