Upcoming cold for the South (Models, Maps, Discussions)

#801 Postby **Portastorm** » Mon Feb 06, 2006 4:05 pm

Wow, I'm kinda surprised by how the NWS discussions so far this afternoon out of Texas offices are all kinda ho-hum about this weekend. Yes, I agreed with some of you earlier when you said 7 days was too far out to get excited. But, most of these offices have already used the A word -- as in "arctic" -- yesterday in their discussions and once you mention it, it's surprising to see such softpeddling language like "frontal passage" and "cooler temps."

Technically, it's accurate but ... :roll:

Extremeweatherguy · #802 Postby **Extremeweatherguy** » Mon Feb 06, 2006 4:09 pm

Portastorm wrote:Wow, I'm kinda surprised by how the NWS discussions so far this afternoon out of Texas offices are all kinda ho-hum about this weekend. Yes, I agreed with some of you earlier when you said 7 days was too far out to get excited. But, most of these offices have already used the A word -- as in "arctic" -- yesterday in their discussions and once you mention it, it's surprising to see such softpeddling language like "frontal passage" and "cooler temps."

Technically, it's accurate but ...

well the models are not really any warmer, and the pattern does not look like it will be any different...so I am assuming that they are not mentioning it so strongly b/c they already did yesterday. They will probably get more detailed into the "arctic" forecast as we get closer. For now, most offices are having to deal with red flag warnings, wind advisories and lots of other things today and probably are not thinking too much about 5 days out right now.

BTW, here is a portion of the Houston HWO issued this morning...this looks hopeful:

A STRONG COLD FRONT IS EXPECTED TO CROSS SOUTHEAST TEXAS FRIDAY
NIGHT USHERING IN SOME OF THE COLDEST WEATHER OF THE SEASON THIS
WEEKEND. FREEZING TEMPERATURES APPEAR LIKELY ACROSS THE INLAND
COUNTIES OF SOUTHEAST TEXAS SATURDAY NIGHT AND POSSIBLY AGAIN
SUNDAY NIGHT.

Extremeweatherguy · #803 Postby **Extremeweatherguy** » Mon Feb 06, 2006 4:12 pm

Also...the Dallas AFD looks hopeful this afternoon..here is part of it:

RETURN FLOW WILL DEVELOP RAPIDLY ON THURSDAY...WITH A SLIGHT WARMING
TREND EXPECTED. MEANWHILE...MEDIUM RANGE GUIDANCE CONTINUES TO SHOW
REMARKABLE CONSISTENCY IN DEVELOPMENT OF A SIGNIFICANT SPLIT FLOW
BLOCKING PATTERN ALONG THE WESTERN COAST OF NORTH AMERICA TOWARD THE
END OF THE WEEK...AS CUT-OFF UPPER LOW MEANDERS NEAR NORTHERN BAJA
AND RIDGING BECOMES STRONGLY AMPLIFIED ALONG THE COAST OF BRITISH
COLUMBIA. OVERALL...THE UPPER FLOW PATTERN WILL BECOME VERY
FAVORABLE FOR AN OUTBREAK OF COLD AIR ACROSS THE SOUTHERN PLAINS
THIS WEEKEND...AND INDEED GUIDANCE FROM THE CMC/ECMWF AND GFSLR SHOW
A 1040-1050 MB HIGH PLUNGING SOUTHWARD ALONG THE LEE OF THE ROCKIES
ON FRIDAY.

HOWEVER...TO COMPLICATE MATTERS FURTHER...THE PREVIOUSLY MENTIONED
UPPER LOW OVER BAJA IS FORECAST TO MOVE ACROSS NORTHERN MEXICO ON
FRIDAY...RESULTING IN A FAVORABLE COMBINATION OF WARM ADVECTION AND
WEAK ISENTROPIC ASCENT FOR PRECIPITATION ACROSS THE SOUTHERN HALF OF
STATE. AS IT APPEARS AT THIS TIME...MOST OF THE PRECIPITATION WILL
OCCUR ON FRIDAY AND FRIDAY NIGHT...WITH PRECIPITATION ENDING AS
COLDER AIR ENTERS THE REGION ON SATURDAY MORNING. HAVE INCREASED
POPS INTO THE CHANCE CATEGORY...GIVEN MODEL CONSISTENCY AND
FAVORABLE PATTERN RECOGNITION. HOWEVER...CHANGES IN FRONTAL TIMING
OR STRENGTH OF THE SOUTHERN STREAM SYSTEM WOULD NECESSITATE CRITICAL
CHANGES IN FORECAST OF PRECIPITATION TYPE. PRECIPITATION WILL CLEAR
THE SOUTHERN ZONES ON SATURDAY MORNING...BUT CLOUDY SKIES AND COLD
ADVECTION WILL LIKELY MAINTAIN TEMPERATURES IN THE 40S FOR MUCH OF
THE AREA ON SATURDAY. A BRIEF WARMING TREND IS EXPECTED ON SUNDAY...
WITH YET ANOTHER WEAKER COLD FRONT PROGGED TO PUSH ACROSS THE AREA
ON MONDAY.

#804 Postby **Portastorm** » Mon Feb 06, 2006 4:13 pm

Yeah as usual I opened my yap too soon! :lol:

Both Lubbock and Fort Worth have decent write-ups about this weekend. Here's a sampling:

LUBBOCK
FIRST WEAK COLD FRONT TO MOVE THROUGH THE REGION WEDNESDAY NIGHT
WITH A SECOND MUCH STRONGER FRONT TO MOVE ACROSS THE AREA ON
FRIDAY WITH A COLD CANADIAN SURFACE HIGH PLUNGING DOWN INTO THE
CENTRAL PLAINS BY SUNDAY MORNING AND TOWARD THE TEXARKANA REGION
BY MONDAY MORNING. THUS TEMPERATURES FOR THE WEEKEND EXPECTED TO
BE BELOW NORMAL.

FORT WORTH
OVERALL...THE UPPER FLOW PATTERN WILL BECOME VERY
FAVORABLE FOR AN OUTBREAK OF COLD AIR ACROSS THE SOUTHERN PLAINS
THIS WEEKEND...AND INDEED GUIDANCE FROM THE CMC/ECMWF AND GFSLR SHOW
A 1040-1050 MB HIGH PLUNGING SOUTHWARD ALONG THE LEE OF THE ROCKIES
ON FRIDAY.

Tyler · #805 Postby **Tyler** » Mon Feb 06, 2006 4:27 pm

Houston NWS kisses the GFS MOS this afternoon. There is no way we're reaching the mid 50's on Saturday. Strong CAA, cloudy, 850MB -4 to -6 degrees C, and we're going to reach the mid 50's!? Don't think so.

cctxhurricanewatcher · #806 Postby **cctxhurricanewatcher** » Mon Feb 06, 2006 4:35 pm

Portastorm wrote:Wow, I'm kinda surprised by how the NWS discussions so far this afternoon out of Texas offices are all kinda ho-hum about this weekend. Yes, I agreed with some of you earlier when you said 7 days was too far out to get excited. But, most of these offices have already used the A word -- as in "arctic" -- yesterday in their discussions and once you mention it, it's surprising to see such softpeddling language like "frontal passage" and "cooler temps."

Technically, it's accurate but ...

Typical inconsitency as discussed many times on here about the AFD's. Trouble is alot of local TV mets (in smaller TV markets) mold their forecasts from what these AFD's.

I really wonder what those old timers from the Brownsville NWS offices would have been saying about this.

Extremeweatherguy · #807 Postby **Extremeweatherguy** » Mon Feb 06, 2006 4:59 pm

Tyler wrote:Houston NWS kisses the GFS MOS this afternoon. There is no way we're reaching the mid 50's on Saturday. Strong CAA, cloudy, 850MB -4 to -6 degrees C, and we're going to reach the mid 50's!? Don't think so.

yeah, seriously. With that set up I would doubt we reached the mid 40s...let alone mid 50s. Of course they will change it though...but it will probably be the DAY OF the event (Example = early Dec. cold snap). The NWS will bust once again...

cctxhurricanewatcher · #808 Postby **cctxhurricanewatcher** » Mon Feb 06, 2006 5:02 pm

Extremeweatherguy wrote:
Tyler wrote:Houston NWS kisses the GFS MOS this afternoon. There is no way we're reaching the mid 50's on Saturday. Strong CAA, cloudy, 850MB -4 to -6 degrees C, and we're going to reach the mid 50's!? Don't think so.
yeah, seriously. With that set up I would doubt we reached the mid 40s...let alone mid 50s. Of course they will change it though...but it will probably be the DAY OF the event (Example = early Dec. cold snap). The NWS will bust once again...

No, they will back track sooner than that. We will start seeing special weather statements talking about the coldest front of the winter season about Thrusday morning.

Extremeweatherguy · #809 Postby **Extremeweatherguy** » Mon Feb 06, 2006 5:07 pm

cctxhurricanewatcher wrote:
Extremeweatherguy wrote:
Tyler wrote:Houston NWS kisses the GFS MOS this afternoon. There is no way we're reaching the mid 50's on Saturday. Strong CAA, cloudy, 850MB -4 to -6 degrees C, and we're going to reach the mid 50's!? Don't think so.
yeah, seriously. With that set up I would doubt we reached the mid 40s...let alone mid 50s. Of course they will change it though...but it will probably be the DAY OF the event (Example = early Dec. cold snap). The NWS will bust once again...

No, they will back track sooner than that. We will start seeing special weather statements talking about the coldest front of the winter season about Thrusday morning.

I hope so... It would be nice if we could actually get some good forecasts from them a few days out. It would give us more time to plan ahead on just how cold it will be.

#810 Postby **gboudx** » Mon Feb 06, 2006 5:12 pm

FTW also mentions the upper low tracking into Northern Mexico. For now, they are putting us with a chance of rain, but they caveated that precip types will depend on timing and strength of the arctic front. Stay tuned.

Extremeweatherguy · #811 Postby **Extremeweatherguy** » Mon Feb 06, 2006 5:16 pm

Here are a few NWS forecasts for areas in SE Texas. This shows you how each NWS has a varying opinion right now:

WACO, TX (Fort Worth NWS)

Friday Night: A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 35. South wind 5 to 15 mph becoming north.

Saturday: A 20 percent chance of showers. Partly cloudy, with a high near 46.

Saturday Night: Mostly clear, with a low around 29.

BEAUMONT, TX (Lake Charles NWS)

Friday Night: A 40 percent chance of showers. Mostly cloudy, with a low around 46. South wind between 5 and 10 mph.

Saturday: A 40 percent chance of showers. Mostly cloudy, with a high around 51.

Saturday Night: Partly cloudy, with a low around 34.

SPRING, TX (Houston NWS)

Friday Night: A 30 percent chance of showers. Mostly cloudy, with a low around 50.

Saturday: A 30 percent chance of showers. Mostly cloudy, with a high near 55.

Saturday Night: Partly cloudy, with a low around 31.

AUSTIN, TX (Austin/San Antonio NWS)

Friday Night: A 20 percent chance of showers. Mostly cloudy, with a low around 47. South wind 5 to 10 mph becoming northwest.

Saturday: A 20 percent chance of showers. Mostly cloudy, with a high around 58.

Saturday Night: Partly cloudy, with a low around 32.

**I think that the Ft. Worth NWS is most in line with the situation right now.**

Extremeweatherguy · #812 Postby **Extremeweatherguy** » Mon Feb 06, 2006 5:20 pm

18Z run of the GFS brings the cold air now well east of SE Texas, and only brings us a little bit of chilly air...may be a high of 57 and low of 32 at coldest. But, then again the 6Z and 18Z runs of the GFS should always be discarded and are usually horrible. I will wait until the 0Z run for any serious thought into the possibility of the air missing us by as much as the 18Z has it missing us...but then again I think that the GFS is having an overall problem in handling this situation and I think that there will be a lot of low level cold air that it is not seeing that will try to sink southward. I am still on for my idea of a high below 45 and a low below 30 this weekend.

Tyler · #813 Postby **Tyler** » Mon Feb 06, 2006 5:33 pm

Extremeweatherguy wrote:18Z run of the GFS brings the cold air now well east of SE Texas, and only brings us a little bit of chilly air...may be a high of 57 and low of 32 at coldest. But, then again the 6Z and 18Z runs of the GFS should always be discarded and are usually horrible. I will wait until the 0Z run for any serious thought into the possibility of the air missing us by as much as the 18Z has it missing us...but then again I think that the GFS is having an overall problem in handling this situation and I think that there will be a lot of low level cold air that it is not seeing that will try to sink southward. I am still on for my idea of a high below 45 and a low below 30 this weekend.

The GFS makes no sence after 84. The high is WAY to weak. Its a 1036 the whole time. The ECMWF/CMC both keep it at 1045MB. Plus, surface maps don't match well to overall flow. LOL, the 0C line going all the way to South Florida!? :lol:

Ahhh, 18z, you always amaze me more every time.

Again, don't worry about it, its all BS past 84. No models support the 18z.

#814 Postby **Portastorm** » Mon Feb 06, 2006 6:05 pm

Even if the 18z was spinning up a nice wintry weather event for us, I wouldn't buy it BECAUSE it is the 18z run of the GFS. Just about worthless.

You guys are on it!

#815 Postby **jasons2k** » Mon Feb 06, 2006 6:07 pm

Extremeweatherguy wrote:Here are a few NWS forecasts for areas in SE Texas. This shows you how each NWS has a varying opinion right now:

**I think that the Ft. Worth NWS is most in line with the situation right now.**

Actually, those all line-up pretty well. Waco, technically in North Central TX, is going to be cooler than our locations here in SE Texas. So their thinking looks pretty spot-on with the other offices (and vice-versa).

If your line of thought verifies and we're in the mid-40's this weekend, then actually they, too, are way off.

Extremeweatherguy · #816 Postby **Extremeweatherguy** » Mon Feb 06, 2006 6:09 pm

jschlitz wrote:
Extremeweatherguy wrote:Here are a few NWS forecasts for areas in SE Texas. This shows you how each NWS has a varying opinion right now:

**I think that the Ft. Worth NWS is most in line with the situation right now.**

Actually, those all line-up pretty well. Waco, technically in North Central TX, is going to be cooler than our locations here in SE Texas. So their thinking looks pretty spot-on with the other offices.

If your line of thought verifies and we're in the mid-40's this weekend, then actually they, too, are way off.

usually though, I have noticed that waco and austin tend to have similar weather. Austin in this case is forecasting 58 and waco 46. I think a 12 degree gap would be too big for this kind of situation.

#817 Postby **Portastorm** » Mon Feb 06, 2006 6:18 pm

OK, I gotta agree with jschlitz and I need to chime in here given the geography we're talking about!

NWS Fort Worth progs highs Saturday for Lampsas and Temple/Killeen/Fort Hood in the upper 40s. NWS Austin/San Antonio progs the high for metro Austin in the mid 50s. Lampsas and Temple are within 30-35 miles of Austin. Given the close proximity and the urban heat island effect that metro Austin frequently displays, these forecasts are actually pretty much in sync and they are coming from two different NWS offices.

For example today ... with decent cold air advection occuring but with maximum sunshine, the areas of north Austin where I live were 3 degrees cooler than downtown. Not unusual at all. So, conceivably it could be 54 on Saturday in Austin and 48 in Lampasas and Temple and I would say both forecasts would be closely aligned.

#818 Postby **jasons2k** » Mon Feb 06, 2006 6:26 pm

Well, I think you're both right

Portastorm is correct, you would be amazed at the differences between Lampasas and Austin, etc. Not only with the heat island effect (although you have to use Mabry not Bergstrom for that) is a factor and especially topography.

In Extremeweatherguy's defense, a 12 degree spread for an afternoon high with a stiff north wind would be quite a spread unless there was still quite a tight temp. gradient with the front passing through. The 58 from Austin did strike me as the one being out of place.

aggiecutter · #819 Postby **aggiecutter** » Mon Feb 06, 2006 7:11 pm

The scenerio laid out by the CPC in its 8-14 day outlook is the algorithm for a Northern Texas-Mid South winter storm. A moderately strong SE ridge with pressing cold air to the north of a baroclinic zone is the classic setup. The low should come out of the gulf and track NE toward Mississippi throwing moisture back into the cold air. This is the setup that has brought NE Texas and Southern Arkansas some of their most memorable winter storms.

http://www.cpc.ncep.noaa.gov/products/p ... ns/814day/

Weatherfreak14 · #820 Postby **Weatherfreak14** » Mon Feb 06, 2006 7:16 pm

Just wondering what the setup is to be thurs for the southeast. Any Huge winter storm still expected?

Upcoming cold for the South (Models, Maps, Discussions)

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