December: Warm Days & Cool-Foggy Nights To End 2011

[brazoriatx]

All this talk of wintry mischief is great but the big picture is rain. That we desperately need how
Much can we expect hopefully we can get 1-3 inches area wide hopefully more in line with 2-4 any input would be greatful

I'll be focusing more on this aspect of the storm system later. HPC QPF guidance suggests around 1-3, but as wxman57 just mentioned, there is a possibility of a Coastal Low/Trough developing down near Corpus, so that may add another kink in the forecast.

hmmm,now wouldnt that be something!

[Rich]

I'll be focusing more on this aspect of the storm system later. HPC QPF guidance suggests around 1-3, but as wxman57 just mentioned, there is a possibility of a Coastal Low/Trough developing down near Corpus, so that may add another kink in the forecast.

So you're saying we should be praying for a coastal low if we want some wintry mischief down here?!?

[brazoriatx]

I'll be focusing more on this aspect of the storm system later. HPC QPF guidance suggests around 1-3, but as wxman57 just mentioned, there is a possibility of a Coastal Low/Trough developing down near Corpus, so that may add another kink in the forecast.

So you're saying we should be praying for a coastal low if we want some wintry mischief down here?!?

i think pray if you want some sleet pellets,no snow tho

[Rich]

I'll be focusing more on this aspect of the storm system later. HPC QPF guidance suggests around 1-3, but as wxman57 just mentioned, there is a possibility of a Coastal Low/Trough developing down near Corpus, so that may add another kink in the forecast.

So you're saying we should be praying for a coastal low if we want some wintry mischief down here?!?

i think pray if you want some sleet pellets,no snow tho

That's what I was thinking too! Gotta keep hope alive!

[srainhoutx]

Morning e-mail from Jeff:

Winter Storm responsible for powerful winds over the SW US moving toward TX.

Strong cold front currently extends from near Dallas to NW of Austin to near Del Rio with temperatures in the 20-40’s behind this front and in the 60-70’s ahead of the front. This front is nearly stationary and will remain near this line for much of the next 24-36 hours. Out west a large trough continues to dig over the SW US and this trough will force downstream pressure falls late today over SW/W TX with surface low formation. Onshore flow of warm and muggy air will remain in place over much of TX east of I-35 for the next 24 hours helping to pump moisture into the region.

Upper trough over the SW US will eject out a shearing piece of energy Saturday late into Sunday pushing the strong cold front over central TX toward the coast. Still some timing differences on how fast the front moves toward the coast with some models showing a Sunday PM coastal passage and others not until Monday afternoon…will side with the faster passage around Sunday afternoon/evening. Prior to the front reaching the area will continue to see a south to north band of showers from roughly Matagorda Bay to west of College Station and this area should see the best rain chances until Sunday when more widespread rains are likely. Could see a few thunderstorms on Sunday along the front/pre-frontal trough, but chances look marginal as instability looks weak.

As the current upper trough shears out on Saturday/Sunday another upper trough digs into the SW US late Sunday creating a classic overrunning pattern over the state. Shallow cold dome will be in place over much of the area by early Monday with warm moist 850mb flow pumping Gulf moisture northward over this cold air mass producing widespread clouds, drizzle, rainfall. Thick clouds and rainfall will keep highs on Monday in the low 50’s. Widespread rains are likely with amounts Saturday of less than .25 of an inch and then .5-1.5 inches on Sunday. Widespread rainfall of 1-2 inches additional will be possible Mon-Tues, producing great drought relief over the region. Slow soaking rainfall may actually create some amounts of run-off into falling lakes. Best post frontal rains look aimed at areas north of I-10 ahead/along the 850mb front, but everyone should see some rainfall over the next 4 days. SW counties around Matagorda Bay remain the driest as recent rains have largely missed this region.

Secondary upper trough will eject across TX Tuesday with rains ending from west to east Tuesday afternoon/evening. Profiles remain warm enough to keep everything liquid over SE TX Tuesday and when profiles start to cool enough to favor frozen precipitation, most of the moisture will be east of the region. Will keep an eye on the NW counties for late Tuesday just in case the models are off on their timing of rainfall ending allowing more cold air to flood the low to mid levels and possibly mixing some of the rain with sleet…this is a remote chance at this point. Most areas will not get much above the mid 40’s on Tuesday for high temperatures.

Upper trough will be east of the area by early Wednesday with clearing skies resulting in potential for freezing conditions possible Wednesday morning, but this is highly dependent on how quickly skies scatter out Tuesday night.

[brazoriatx]

one thing about living in houston..its either cold enough but doesnt have any moisture..or we have plenty of moisture but its not cold enough..man! lol

[wxman57]

I'd say it's more than just a chance of a coastal low, it's nearly a certainty. Perfect setup - stationary front just offshore and a big vorticity max moving into the state Monday with the upper trof. Classic west Gulf low setup. If the air aloft was another 5-8 degrees colder than it's a setup for snow. Not this time, however. Maybe later in the month or in Jan/Feb.

[brazoriatx]

I'd say it's more than just a chance of a coastal low, it's nearly a certainty. Perfect setup - stationary front just offshore and a big vorticity max moving into the state Monday with the upper trof. Classic west Gulf low setup. If the air aloft was another 5-8 degrees colder than it's a setup for snow. Not this time, however. Maybe later in the month or in Jan/Feb.

so getting some sleet is more than possible?

[djmike]

Never say never! ....as we all know here in SETX, anything can happen especially when we least expect it. Remember the last few years?

[Andrew]

I'd say it's more than just a chance of a coastal low, it's nearly a certainty. Perfect setup - stationary front just offshore and a big vorticity max moving into the state Monday with the upper trof. Classic west Gulf low setup. If the air aloft was another 5-8 degrees colder than it's a setup for snow. Not this time, however. Maybe later in the month or in Jan/Feb.

so getting some sleet is more than possible?

No it is still a relatively low chance. Temps will just be a little too warm but I think a couple of sleet pellets could still be possible. Just nothing big.

[wxman57]

I'd say it's more than just a chance of a coastal low, it's nearly a certainty. Perfect setup - stationary front just offshore and a big vorticity max moving into the state Monday with the upper trof. Classic west Gulf low setup. If the air aloft was another 5-8 degrees colder than it's a setup for snow. Not this time, however. Maybe later in the month or in Jan/Feb.

so getting some sleet is more than possible?

It's a little of a stretch here, but not unlikely that we see a few sleet pellets mixed with the rain as the precip ends on Tuesday.

[Ptarmigan]

Next week looks interesting with a strong cold front and possible coastal low, which makes it more interesting in terms of rain amount and even wintry precipitation. In many ways, predicting winter weather in Houston is difficult and more so than compared to hurricanes.

[srainhoutx]

The 12Z GFS has trended more in line with the Euro. The Canadian suggests a coastal low/trough developing near Corpus late Sunday night into Monday throwing a lot of moisture over the shallow cold air at the surface.

[brazoriatx]

The 12Z GFS has trended more in line with the Euro. The Canadian suggests a coastal low/trough developing near Corpus late Sunday night into Monday throwing a lot of moisture over the shallow cold air at the surface.

yay so we r going to get some more rain!

[biggerbyte]

Perfect setup to yank even more cold air across the area, as well as throw more moisture on top of it..

Muhahahaha

[srainhoutx]

One of the main issues with the guidance has been when and where will the 2nd upper air disturbance (500mb) travel as it heads E. The 12Z Euro suggests a track very near the Red River Valley/N TX. That will be one of the interesting developments to watch over the weekend as there have been a lot of questions in the forecast as to just how/where that disturbance eventually ejects.

[srainhoutx]

The HPC updated graphics now suggest a Coastal Low developing near Corpus...

[TexasMetBlake]

GFS now showing snow for College Station:

http://68.226.77.253/text/1DegGFS/GFS_Kcll.txt

[srainhoutx]

Not to get too far ahead of ourselves here but if the Euro is correct, we'll be back into a very interesting situation next weekend. But that is for another day...for now...

[unome]

Dallas NWS Multi-Media Weather Briefing 12/2 - 10:30 am

http://www.srh.noaa.gov/media/fwd/12022 ... layer.html

explains it well, in one "shabang"

edit to add HGX briefing from Dec 2nd: http://www.srh.noaa.gov/hgx/?n=briefing