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

[wxman57]

12Z GFS is a good deal wetter for this coming Sunday. Gradual warming trend until then. Indicates a light freeze next Tuesday:

[srainhoutx]

The Euro/Canadian/UKMET suggest a slower progression of the front/trough and keep the 5H (Upper Air) low back to the W. It certainly could lead to another decent rainfall event in the 'warm' air. Further N and W into N MX/TX Panhandle/OK, wintry precip chances does appear to be increasing.

[Kludge]

12Z GFS is a good deal wetter for this coming Sunday. Gradual warming trend until then. Indicates a light freeze next Tuesday:

Excellent...!!! Looks lke perfect weather for Saturday @ 11 as the Undefeated and Number 6 in the Nation Houston Cougars play for the Conference Championship and a Major BCS Bowl Invitation

[texoz]

my son is supposed to play in a soccer tourn in Temple, TX (just south of Waco) on Sat/Sun. I'll be following you guys here closely to see if there's a chance for wintry weather that far south. For now, do you see any chance of that? And for the rain, are we talking light showers, or possible heavy rain event over central Texas? thx

[srainhoutx]

Again this morning I'll post the morning e-mail from Jeff in the December topic as there is interest in what is ahead for late week into the weekend. As Jeff mentions, this is a low confidence forecast due to model mayhem, but certainly worth following as there could be some big changes in the days ahead depending on how the guidance actually plays out:

Another clear and cold morning across the region with temperatures currently in the low to mid 30’s

Secondary surge of colder air will arrive today from the north with winds briefly increasing out of the NW of 10-15mph. This surge will help reinforce the cold and dry air mass already in place and continue to yield lows in the 30’s and highs in the 60’s today and Wednesday. 1025mb surface high pressure dome will shift eastward Thursday allowing SE winds to return to the region, but moisture return will be slow as the air mass over the Gulf has been scoured by the recent cold frontal intrusion. While out west a piece of energy will break off from the northern jet stream and dig southward into the SW US cutting off from the main polar jet stream and upper air flow across the US (a SW US cut off low). The polar stream short wave will continue eastward dragging a strong polar boundary into TX late this week. Unfavorable SW flow aloft due to the digging trough over the SW US and the departing northern stream trough does not support a significant frontal push across TX. In fact the models may be coming into some weak agreement on stalling the boundary across SW to NC TX this weekend. While this may be what the models are suggesting, cold dense air masses tend to bleed southward undercutting unfavorable flow aloft (but how far south) if the question that is nearly impossible to answer. Currently thinking is that the front will stall north and west of SE TX so a gradual warming and moistening trend into the weekend.

Next big item is when and how (what form) does the SW US energy eject into the southern plains. GFS brings the system through the fastest and opens the low as it moves across while the ECMWF and CMC both eject a piece and then quickly reform a secondary upper low again back over the SW US early next week. GFS solution would result in a good shot a rainfall over the weekend followed by a strong polar front through the area and off the coast early next week with some very cold temperatures possible behind the late weekend front. The ECMWF and CMC would support a much warmer and slower frontal passage and then a period of overrunning into early next week as the secondary energy hangs back to the west. Each of the models have been somewhat consistent in their own handling of the weekend storm system, but none on the same page. Ensembles do support more of the progressive GFS solution and most NWS offices are falling in line with that thinking at the current time.

With this reasoning in mind will go with increasing rain chances late Friday into Saturday as the SW US storm forces downstream pressure falls and a rapid influx of Gulf moisture. Rain chances will likely peak over SE TX Saturday afternoon-Sunday near/behind the polar frontal boundary. It should be noted that the best rain chances will be over central and north TX where additional much needed rainfall appears fairly likely late Thursday-Sunday. This is an overall low confidence forecast and some big changes could result over the next few days.

[redneckweather]

I will be heading out early Friday morning for our deer hunt which will be about 20 minutes outside of Meridian. With polar air coming down, I am leaning towards a polar frontal passage in this area coming through Friday sometime and stalling south of the area thinking we will be in the cold sector. Thoughts?

[wxman57]

Meridian, TX being NW of Waco? I made a meteogram from the 6Z GFS (below). GFS is saying cold rain Friday and Saturday. I'd really question that 67 for Saturday's high with the rain. Just what I remember from deer hunting with my father about 45 years ago - cold and rainy (and I was just trying to keep warm and dry all during the hunt).

The only good news is that my confidence in the GFS's forecast is not good. The Canadian and Euro offer a different solution, with less pre-frontal rain and a slower movement of cold air southward. Have to wait another day or two for a better idea of what's going to happen Saturday/Sunday.

[srainhoutx]

The 12Z GFS continues to advertise an upper air disturbance dropping into the SW and then shearing that feature out into a more troughy pattern elongated from the SW to NE. What will need to be monitored in future guidance is the development of a Coastal Low/Trough that provides for some over running and light rain once the front passes late Saturday night/Sunday morning. The GFS suggests a line of showers as the front moves by and then keeps us in the clouds with cooler temps and light rain chance into Monday. The big question will be if the southern stream energy can phase with a northern stream shortwave allowing colder air to head S. Regardless, it does appear the first winter storm of the season is taking shape for the Central/Southern Rockies and wintry mischief could settle as far S as W TX and the Panhandle. We’ll see what the rest of the operational guidance suggest, but also remember that guidance has been extremely poor in handling the pattern beyond day 3. The upper air feature that drops into he SW will not reach the RAOB network until sometime tomorrow as that feature is nearing the Gulf of Alaska/Pacific NW.

[weatherguy425]

Srain, I know I'm up here in Lubbock now... but I was wondering if I could have your take on the weather in my area. Models have been showing quite a winter storm , at time the GFS was showing accumulations of 6+ inches. The past couple runs have trended further north with the disturbance though... allowing a warm nose to develop and transition the precip over to rain/freezing rain. I haven't really been keeping track of the Euro. I know it's far out and this system hasn't even been sampled...but what do you think?

[srainhoutx]

Srain, I know I'm up here in Lubbock now... but I was wondering if I could have your take on the weather in my area. Models have been showing quite a winter storm , at time the GFS was showing accumulations of 6+ inches. The past couple runs have trended further north with the disturbance though... allowing a warm nose to develop and transition the precip over to rain/freezing rain. I haven't really been keeping track of the Euro. I know it's far out and this system hasn't even been sampled...but what do you think?

I saw the Special Weather Statement this morning for Lubbock and they have been leary to bite on any solution given the fact that guidance has just not performed well beyond the 3 day time frame. That said, the new Canadian just trended to what the GFS has suggested regarding opening up the upper air disturbance in the SW and dropping another 5H (500mb) disturbance in the upper airflow into the Desert SW. We'll just need to watch and see how guidance handles everything in the next couple of days. This is a very tricky forecast with these upper lows and accurately forecasting what the different thermal layers will be at multiple levels. Hopefully once the features get into the RAOB network guidance will begin to hone in on a more trust worthy solution.

[weatherguy425]

Yeah, and it looks like some mighty cold air will be in place if that second disturbance does in fact come to fruition.

[srainhoutx]

The 12Z Euro trended slightly with what the GFS and Canadian offered today in suggesting a bit of shearing out of the SW upper air disturbance before dropping another 5H (upper low) in the Desert SW. Also of note, the Euro is beginning to come around to the idea of colder weather dropping S behind the front and setting the stage for another possible freeze event early next week. This is all subject to change, but this does bode well with a little better agreement in model world in regards to what could happen as we look ahead. It still appears a Winter Storm is shaping up for the Central/Southern Rockies into the Panhandle of TX and points NE over the weekend. We will see…

[srainhoutx]

And just for grins, the long range Operation 12Z Euro...

[srainhoutx]

HPC surface feature charts for the upcoming weekend into early next week...

[srainhoutx]

With the 12Z Operational guidance now in, Special Weather Statements for cold and possible wintry michief are being issued from Midland/Odessa to N MX and points N into Panhandle's of TX/OK as well as SW Kansas.

[JackCruz]

(I'm not too knowledgeable about the weather models, now learning)

Okay so I'm looking at the GFS models on Wunderground and I saw the cold coming in to Houston early next week, it looks to produce about the same temperatures we saw during the beginning of this week...even KHOU forecast a high of 55 and a low of 34 next week on Tuesday...however every other forecasters and website have different numbers and even amounts of precip...so far I don't see any precip on Tuesday when I watched the news today. On Accuweather.com however, On Monday and Tuesday it looks interesting. On Monday the high will be 66 and the low around 36 (rain throughout the day...cloudy during the night)...on Tuesday the high 56 and low 34 (mostly cloudy)

Am I over-thinking this or can this lead to something? Because the GFS is showing sufficient precip not just for ONE day of next week...but for about 3 days.

[JackCruz]

Do you guys think we can get some sleet (at least) around Monday/Tuesday night around Cypress area? or north NW Houston?

I've been looking at the GFs and it's showing sleet to the West of Houston...just a small pocket of sleet...not close enough though.

It's showing a lot of moisture also....and the forecast according to KHOU calls for a low of 35 on Tuesday....but with sunny skies? I think it'll be more cloudy and maybe some drizzle instead of rainy. Accuweather shows lows in the mid 30s for both Monday and Tuesday night with rain on Monday but CLOUDY/ Overcast Monday night (36 degrees) and Tuesday. Tuesday they're showing it to be cloudy with a high of 56 and low of 34...but the GFS is showing much precip around this time frame.


"S" word soon? Or no?

[srainhoutx]

(I'm not too knowledgeable about the weather models, now learning)

Okay so I'm looking at the GFS models on Wunderground and I saw the cold coming in to Houston early next week, it looks to produce about the same temperatures we saw during the beginning of this week...even KHOU forecast a high of 55 and a low of 34 next week on Tuesday...however every other forecasters and website have different numbers and even amounts of precip...so far I don't see any precip on Tuesday when I watched the news today. On Accuweather.com however, On Monday and Tuesday it looks interesting. On Monday the high will be 66 and the low around 36 (rain throughout the day...cloudy during the night)...on Tuesday the high 56 and low 34 (mostly cloudy)

Am I over-thinking this or can this lead to something? Because the GFS is showing sufficient precip not just for ONE day of next week...but for about 3 days.

First off, Welcome to our online weather community, JackCruz. I moved your topic into the December discussions. Chances of anything wintery mischief wise here in the Houston area doesn't look at all likely at this time. Further N and W of Austin and the Hill Country area may be a different story. We will see.

[JackCruz]

(I'm not too knowledgeable about the weather models, now learning)

Okay so I'm looking at the GFS models on Wunderground and I saw the cold coming in to Houston early next week, it looks to produce about the same temperatures we saw during the beginning of this week...even KHOU forecast a high of 55 and a low of 34 next week on Tuesday...however every other forecasters and website have different numbers and even amounts of precip...so far I don't see any precip on Tuesday when I watched the news today. On Accuweather.com however, On Monday and Tuesday it looks interesting. On Monday the high will be 66 and the low around 36 (rain throughout the day...cloudy during the night)...on Tuesday the high 56 and low 34 (mostly cloudy)

Am I over-thinking this or can this lead to something? Because the GFS is showing sufficient precip not just for ONE day of next week...but for about 3 days.

First off, Welcome to our online weather community, JackCruz. I moved your topic into the December discussions. Chances of anything wintery mischief wise here in the Houston area doesn't look at all likely at this time. Further N and W of Austin and the Hill Country area may be a different story. We will see.

Thank you very much for the warm welcome. I hope we get something by mid Jan. Wishful thinking. Loving the colder temps though.

[srainhoutx]

A very complicated forecast is shaping up for late week into early next week. The guidance continues to differ in the handling of the various features and where frontal boundaries will stall and with the upper air disturbances to our W in AZ. The best guess is moisture and clouds will begin to increase late Thursday across the Lone Star State as high pressure moves E and pressures falls to our W. The northern stream will send a cold front S into TX Thursday night/Friday morning and a 500mb mid/upper low cuts off in the Desert SW. Over running rains and even wintry mischief is possible across W TX and parts of the Permian Basin, N of the Hill Country. The NAM is coming in with much colder air in that region while the GFS is not as cold. The Euro/Canadian models suggest the Upper Low will linger over AZ throughout the weekend. It does appear that showers and even a few storms could be possible late Saturday into Sunday for our area as the cold front finally sags S into our region. Over running light rain is possible behind the front with a SW flow aloft and a shallow layer of cold air until the upper air disturbance to our W ejects E. Winter Weather conditions are possible throughout the weekend for N MX, parts of W TX and the Panhandle and even as far S as Abilene. Things look to finally clear out early next week with even colder weather possible in the long range. We will see...