SE TX weather thread #4 - Severe weather Fri/Sat

[cctxhurricanewatcher]

We need another thread now. EWG care to start one?

what do you mean another thread? We don't need to start a new one until this reaches 25 pages.

Oh, OK. I guess I meant a new title.

[JenBayles]

With all the eyes on the next cold snap, I have a dumb question - what's driving the slight pops (30%) Monday thru Wednesday? Nice as this weather is, I'm ready for some clouds and hopefully some rain to break the monotony before the front goes thru. Also tired of dragging around the water hose in late November!

[Extremeweatherguy]

With all the eyes on the next cold snap, I have a dumb question - what's driving the slight pops (30%) Monday thru Wednesday? Nice as this weather is, I'm ready for some clouds and hopefully some rain to break the monotony before the front goes thru. Also tired of dragging around the water hose in late November!

Increasing moisture from the GOM ahead of the front should lead to a slight chance of storm Monday and Tuesday and then by Wednesday the front moves closer and with good upper dynamics the storms could become strong to severe. Going to be interesting for sure ahead of the cold snap.

[JenBayles]

Are you thinking a squall line type of event with the frontal passage? I wouldn't be surprised with such different air masses colliding. Guess it just depends on how much Gulf moisture gets pumped up ahead of it?

[Extremeweatherguy]

Are you thinking a squall line type of event with the frontal passage? I wouldn't be surprised with such different air masses colliding. Guess it just depends on how much Gulf moisture gets pumped up ahead of it?

Here is the discussion from the SPC:

http://www.spc.noaa.gov/products/exper/ ... 48prob.gif

...DISCUSSION...

LATEST MEDIUM RANGE GUIDANCE CONTINUES TO SHOW VARIANCE IN AMPLITUDE
AND TO SOME DEGREE SPEED AT WHICH FULL LATITUDE TROUGH WILL PROGRESS
EWD ACROSS THE CNTRL AND ERN PART OF THE NATION. MOREOVER...LAPSE
RATES ARE FORECAST TO BE MARGINAL WITH RICHER BOUNDARY-LAYER AIR
MASS AND RESULTING INSTABILITY REMAINING CONFINED TO THE GULF
COAST.

HOWEVER...GIVEN THE ANTICIPATED STRENGTH OF THE WIND FIELDS AND
DYNAMIC FORCING FOR ASCENT...SOME THREAT OF SEVERE STORMS WILL EXIST
ALONG AND AHEAD OF COLD FRONT IS IT PUSHES THROUGH E TX EWD ACROSS
THE GULF COAST STATES WEDNESDAY NOVEMBER 29TH AND THURSDAY NOVEMBER
30TH.

[double D]

I was browsing through the NWS AFD's and found the Midland/Odessa kind of interesting. I think the trend of lowering highs will continue with other NWS' through out the state.

.LONG TERM...
WILL BEGIN THE LONG TERM IN SOUTHWESTERLY FLOW. SEVERAL WEAK
SHORTWAVES WILL TRANSLATE THROUGH THIS FLOW ON SUNDAY AND MONDAY.
SUNDAY...LIFT ASSOCIATED WITH BOTH A SHORTWAVE AND THE RIGHT
ENTRANCE REGION OF A STRONG 250MB JET COULD BE ENOUGH FOR SOME LIGHT
RAIN OVER SOUTHEASTERN NEW MEXICO. HOWEVER...CONFIDENCE IS LOW
ENOUGH THAT THE GOING FORECAST WITH POPS IN THE LOW TEENS WILL BE
LEFT ALONE. 850MB AND BOUNDARY LAYER RH PROGS INDICATE THAT LOW
CLOUDS WILL DEVELOP SOMETIME OVERNIGHT AND STICK AROUND FOR THE
MORNING ACROSS MUCH OF THE AREA AND POSSIBLY REDEVELOP EARLY MONDAY
MORNING.

THE GUADALUPE MOUNTAINS WILL BEGIN TO SEE AN INCREASE IN WINDS
MONDAY...WITH 700MB WINDS INCREASING TO 35-40KTS. SOME MID-LEVEL
SUBSIDENCE DEVELOPS MONDAY OVER THE MOUNTAINS WHICH COULD AID IN
SOME WINDIER CONDITIONS. 700MB WINDS INCREASE TUESDAY TO 45-50KTS
WITH MID-LEVEL SUBSIDENCE OCCURRING AGAIN ON AND OFF THROUGHOUT THE
DAY. AT THIS TIME...THE TIMING OF THE BEST WINDS AND THE BEST
SUBSIDENCE ISN/T IN AGREEMENT...SO WILL JUST MENTION THE POSSIBILITY
OF HIGH WINDS IN THE HWO. LATER SHIFTS MAY DECIDE TO ISSUE A HIGH
WIND WATCH IF CONDITIONS BECOME BETTER ALIGNED.

A SURFACE LOW WILL SET UP IN THE LEE OF THE ROCKIES ON TUESDAY AND
APPEARS TO INDUCE A BARRIER JET OF 40-60KTS AT THE 850MB LEVEL.
THIS WILL ALLOW THE ARCTIC COLD FRONT TO PROGRESS FURTHER SOUTH THAN
THE MODELS CURRENTLY INDICATE. AHEAD OF THE FRONT...THE REGION WILL
EXPERIENCE TEMPERATURES ABOUT 10 DEGREES ABOVE NORMAL TUESDAY.
HIGHS WILL BE SIMILAR TO WHAT THEY/VE BEEN THIS WEEK...MOSTLY IN THE
LOW TO MID 70S. WEDNESDAY IS A DIFFERENT STORY. AFTER THE ARCTIC
FRONT MOVES THROUGH THE AREA...EXPECT A DRAMATIC CHANGE WITH HIGHS
OPTIMISTICALLY IN THE LOW TO MID 40S. USING 850MB TEMPS AS A GUIDE
AND LOW CLOUDS LIKELY ACCOMPANYING THE FRONT...HIGH TEMPS WEDNESDAY
ARE MORE LIKELY TO BE IN THE LOW TO MID 30S. AT THIS POINT...MAY
LOWER CURRENT TEMPS A FEW DEGREES BUT WILL KEEP THEM ON THE WARM
(RELATIVELY) SIDE FOR NOW. TEMPERATURES WILL WARM ONLY SLIGHTLY ON
THURSDAY THEN AN UPPER LEVEL RIDGE WILL BEGIN TO BUILD INTO THE AREA
AND TEMPERATURES SHOULD REBOUND INTO THE 50S. FOR MORE ON THE
ARCTIC AIR...SEE THE SPECIAL WEATHER STATEMENT ISSUED THIS AFTERNOON
(SPSMAF).

[Extremeweatherguy]

Interesting Thursday night forecast coming in from Beaumont this afternoon...

Thursday Night: A 20 percent chance of showers. Mostly cloudy, with a low around 37.

Precip. + cold temps. = An interesting scenatrio (especially since 37F is likely too warm)

BTW, here is the forecast for Jasper (just slightly NE of Beaumont):

Thursday Night: Mostly cloudy, with a low around 33.

If this is a continuing trend, then wintery precip. may not be out of the question!

still though, the Lake Charles NWS showing highs in the upper 50s is crazy talk IMO. Those type of numbers are way too warm.

[double D]

The trend continues with San Angelo NWS. Also they think the ECMWF and GFS are way too slow on the frontal passage.
.LONG TERM...
WEDNESDAY CONTINUES TO BE THE BIG QUESTION WITH REGARDS TO FRONTAL
TIMING. MODELS TYPICALLY HAVE REAL ISSUES WITH ARCTIC FRONTS. JUST
TOO SHALLOW AND DENSE TO HANDLE WELL. HAVE GONE WITH A FRONTAL
TIMING 6 TO 12 HOURS FASTER THAN THE GFS OR ECMWF...ALTHOUGH
UNCERTAINTY REMAINS HIGH. THIS WOULD STILL ALLOW THE SOUTHERN
COUNTIES TO SEE SOME HEATING...AND HAVE STAYED PRETTY CLOSE TO
GUIDANCE FOR THESE AREAS.

THURSDAY AND FRIDAY LOOK COLD...AND EVEN WITH A LOT OF MODIFICATION...HAVE
UNDERCUT GUIDANCE NUMBERS A FEW DEGREES.

[Extremeweatherguy]

Another weird forecast this afternoon is from the Houston NWS:

Wednesday Night: A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 52.

Thursday: Mostly cloudy, with a high near 59.

Thursday Night: Clear, with a low around 36.

Friday: Sunny, with a high near 57.

If we wind up that warm within such a cold arctic airmass overhead, I would be 100% amazed. I just do not see how they could forecast like that. In fact, they even decided to RAISE Thursday night's low from 34. Is it just me...or are they crazy? lol.

They are probably going to end up busting on these numbers by at least 3-6F, if not more.

BTW, compare Houston's forecast with that of Victoria well to our SW:

Thursday: A 20 percent chance of rain. Partly cloudy, with a high near 54.

Thursday Night: Mostly clear, with a low around 32.

Friday: Sunny, with a high near 55.

Interesting, isn't it? Especially when you keep in mind that we are talking about -30 to -50 degree air in western canada and a 1050mb+ high!!! I have never, ever before seen those type of conditions bring the south conditions similar to that of a "typical" early December canadian front. Those conditions are ARCTIC and should be forecasted that way.

[Extremeweatherguy]

The trend continues with San Angelo NWS. Also they think the ECMWF and GFS are way too slow on the frontal passage.
.LONG TERM...
WEDNESDAY CONTINUES TO BE THE BIG QUESTION WITH REGARDS TO FRONTAL
TIMING. MODELS TYPICALLY HAVE REAL ISSUES WITH ARCTIC FRONTS. JUST
TOO SHALLOW AND DENSE TO HANDLE WELL. HAVE GONE WITH A FRONTAL
TIMING 6 TO 12 HOURS FASTER THAN THE GFS OR ECMWF...ALTHOUGH
UNCERTAINTY REMAINS HIGH. THIS WOULD STILL ALLOW THE SOUTHERN
COUNTIES TO SEE SOME HEATING...AND HAVE STAYED PRETTY CLOSE TO
GUIDANCE FOR THESE AREAS.

THURSDAY AND FRIDAY LOOK COLD...AND EVEN WITH A LOT OF MODIFICATION...HAVE
UNDERCUT GUIDANCE NUMBERS A FEW DEGREES.

I wish the Houston NWS would be like that. Instead though, they like to rely heavily on the MOS guidance and they tend to always be way to warm beyond day 4 or 5.

[double D]

I've noticed that too. They tend to be one of the most conservative NWS when it comes to tempertaures. I guess they figure better be safe than sorry.

[JenBayles]

Yeah, but they play it SO safe sometimes, it's unsafe for the public. Like waiting until we're flooding to up rain chances from 30% to 90%. I can't tell you how many times I've read the discussion, and then when you look at the resulting forecast, it reflects nothing they wrote in the discussion. GGGRRRRR!

[Extremeweatherguy]

The morning Houston NWS shift is a little bit better, but compared to other NWS offices across the state, Houston is certainly the most conservative (along with Beaumont). They like to wait until something is imminent before going too drastic with their forecast. The morning NWS shift is a little bit better though (and will usually set the standard for the afternoon shift). That is why I enjoy the morning forecasts and discussions the most. I HOPE that by tomorrow the forecast has been lowered (so I don't have the cringe when I hear on air local mets regurgitate the warm numbers). I just hope everyone is adequately prepared for this cold snap in our area, and prefrably a few days in advance. I remember the last freeze we had here was forecast to be 37-40F the day before (it ended up that I hit 30F and the airport hit 32F).

[cctxhurricanewatcher]

The trend continues with San Angelo NWS. Also they think the ECMWF and GFS are way too slow on the frontal passage.
.LONG TERM...
WEDNESDAY CONTINUES TO BE THE BIG QUESTION WITH REGARDS TO FRONTAL
TIMING. MODELS TYPICALLY HAVE REAL ISSUES WITH ARCTIC FRONTS. JUST
TOO SHALLOW AND DENSE TO HANDLE WELL. HAVE GONE WITH A FRONTAL
TIMING 6 TO 12 HOURS FASTER THAN THE GFS OR ECMWF...ALTHOUGH
UNCERTAINTY REMAINS HIGH. THIS WOULD STILL ALLOW THE SOUTHERN
COUNTIES TO SEE SOME HEATING...AND HAVE STAYED PRETTY CLOSE TO
GUIDANCE FOR THESE AREAS.

THURSDAY AND FRIDAY LOOK COLD...AND EVEN WITH A LOT OF MODIFICATION...HAVE
UNDERCUT GUIDANCE NUMBERS A FEW DEGREES.

I wish the Houston NWS would be like that. Instead though, they like to rely heavily on the MOS guidance and they tend to always be way to warm beyond day 4 or 5.

"CLASSIC EXAMPLE OF HOW AUTOMATION AND LAZINESS CAN BURN YOU."

That's the title of one of JB's updates today in reference to the threat of snow in Seattle. I think at times the same goes for some shifts at the NWS offices here in Texas and other points in the south with Arctic Air. I did notice the DFW office thinks the GFS numbers are garbage at this point and are going lower.

[Extremeweatherguy]

The 18Z GFS is odd looking and should probably be thrown out, but it is interesting to note that it shows a huge winter storms for SE Texas. The latest run brings a period of sleet and snow through the area on Friday afternoon (and even shows ACCUMULATION!). This is completely different from the other runs though, so I am not buying into it yet. If this trend continues though, then we may have to really watch closely. This could get interesting..

BTW: Another interesting note is that it is showing this only about 5-6 days out (instead of the fantasy day 9-16 storms it usually shows). A winter storm depicted closer than a week out is noteworthy for sure from the GFS (If it becomes a trend that is).

[double D]

That run is probably the outlier, I think the air behind this front is very dry and moisture does not seem to be available. Saying that, I would not rule anything out as we have seen stranger things happen before.

[weatherrabbit_tx]

got a feeling that nws offices in the southern part of texas are in for a big surprise and to boot some people that dont ever know about this website and bastardi, see the weather channel extented has the woodlands,tomball,katy down to 27 saturday I'm afraid that may have to be lowered

[Extremeweatherguy]

got a feeling that nws offices in the southern part of texas are in for a big surprise and to boot some people that dont ever know about this website and bastardi, see the weather channel extented has the woodlands,tomball,katy down to 27 saturday I'm afraid that may have to be lowered

27F is sure a hell of a lot better than the NWS. I would rather them see that than the NWS forecast right now. However, I do agree that even their forecast is probably too high. Highs in the 40s to near 50 (or 10F colder IF the precip. does indeed occur) Thursday and Friday, and lows in the lower to middle 20s Saturday morning seem more likely.

This reminds me a lot of last Decembers cold snap. The NWS was doing the same thing they were now...highs in the 50s and lows in the mid 30s...but it ended up being MUCH colder with a high of 37F at IAH and a 8-16+ hour stretch of freezing temps (with sleet, frz. rain and snow reported just off to our NW).

[weatherrabbit_tx]

The 18Z GFS is odd looking and should probably be thrown out, but it is interesting to note that it shows a huge winter storms for SE Texas. The latest run brings a period of sleet and snow through the area on Friday afternoon (and even shows ACCUMULATION!). This is completely different from the other runs though, so I am not buying into it yet. If this trend continues though, then we may have to really watch closely. This could get interesting..

BTW: Another interesting note is that it is showing this only about 5-6 days out (instead of the fantasy day 9-16 storms it usually shows). A winter storm depicted closer than a week out is noteworthy for sure from the GFS (If it becomes a trend that is).

if that were to happen god help us, most drivers have trouble driving when its dry much less when something strange is throwin' like rain/ice or even snow, just speaking for the houston metro.....salt or sand trucks......thinking for the best here

[weatherrabbit_tx]

The 18Z GFS is odd looking and should probably be thrown out, but it is interesting to note that it shows a huge winter storms for SE Texas. The latest run brings a period of sleet and snow through the area on Friday afternoon (and even shows ACCUMULATION!). This is completely different from the other runs though, so I am not buying into it yet. If this trend continues though, then we may have to really watch closely. This could get interesting..

BTW: Another interesting note is that it is showing this only about 5-6 days out (instead of the fantasy day 9-16 storms it usually shows). A winter storm depicted closer than a week out is noteworthy for sure from the GFS (If it becomes a trend that is).

if that were to happen god help us, most drivers have trouble driving when its dry much less when something strange is throwin' like rain/ice or even snow, just speaking for the houston metro.....salt or sand trucks......thinking for the best here