Texas Fall 2012

[Rgv20]

Should watch the EPAC closely, GFS has been trying to throw Rosa-to-be into the mix of fun and games late month.

12&18zGFS is eye candy right now


12zGFS on October 30th has a 997mb low near Laredo which looks to be the remnant energy of Rosa to be..


18zGFS on Halloween day has a 993mb low just East of Brownsville which also looks to be energy from Rosa to be..

[Ntxw]

0z GFS follows in line with the ideas. The kind of blocking that's been shown for many many runs is absolutely ridiculous. It's going to create (if verified) such a large dome of cold air over North America and stick it there. It won't be transient even if we get half of the blocking down. The upcoming pattern is better than anything we have seen ALL of last year let alone for Oct/Nov.

http://mag.ncep.noaa.gov/NCOMAGWEB/appc ... mageSize=M

If we look at current 500mb charts, changes are taking place over Alaska and western Canada. High pressure is building and cold pool emerging over British Columbia and the Yukon. The storm currently over the lakes will begin to pump up the ridge into Greenland (-NAO).

[Portastorm]

While it is a harsh term, especially for our family friendly Storm 2K forum, this is what is called model stuff.

I'd rather we saw this kind of set up in December ... but I guess beggars can't be choosers.

[Ntxw]

12z GFS is even more robust, sending the 850 0c line into central Texas.

Source region, below 0 temps are coming in with the building high over Alaska.

[Tireman4]

Please come down Mr Front. Bring your goodness of cold with you. This upcoming week will be just lovely. Not. I have a race, which I am debating about running it ( due to injuries), October 27 at 7 am. Here is a question. I do wonder will be in the process of coming through at that time or after? Humm...

[iorange55]

Wow, you're right, Ntxw. The 12z GFS looks like a model run you might see in December or January; not late October.

[Ntxw]

CPC just flipped their tune 180 and went colder.

[Portastorm]

Hmm ... Wxman57 better take stock of his cold-weather riding gear.

[Rgv20]

If the GFS were to verify it looks like the whole state of Texas will be in for a cool weekend! GFS Ensembles Mean has below normal temperatures in the range of 12-18 degrees Fahrenheit. ECMWF has the front a bit later and not as strong as the GFS tho..

12zGFS Ensembles Temperature Anomalies for Saturday



12zGFS Ensembles Temperature Anomalies for Sunday

[weatherdude1108]

One of the models had a possible freeze next weekend for central Texas.


.PREV DISCUSSION... /ISSUED 405 AM CDT SUN OCT 21 2012/

DISCUSSION...
HUMID AND ABOVE NORMAL TEMPERATURES WILL CONTINUE FOR A FEW MORE
DAYS BEFORE A MUCH COOLER PATTERN SETTLES OVER SOUTH CENTRAL TX LATE
FRIDAY INTO THE WEEKEND.

A PROGRESSIVE ZONAL PATTERN ALOFT WITH AN UPSTREAM DISTURBANCE
PASSING NORTH OF SOUTH CENTRAL TEXAS OVER THE NEXT COUPLE DAYS
WILL REINFORCE DEEP LOW LEVEL MOISTURE AND STABLE AIR ALOFT. THE
BREEZY SOUTH LOW LEVEL WINDS FEEDING INTO THIS PATTERN ALOFT WILL
PROMOTE A FEW MORNING SHOWERS...BUT NO SIGNIFICANT RAINFALL
AMOUNTS ARE EXPECTED. DAYTIME GUSTY WINDS WILL BE STRONGEST
TODAY...THEN TAPERING OFF SOME AS THE DISTURBANCE PASSES TO THE
NORTH MONDAY. RAIN CHANCES FROM THE DISTURBANCE CONTINUE TO BE
SHOWN MAINLY NORTH OF THE AREA...BUT A FEW THUNDERSTORMS COULD
FORM BRIEFLY OVER THE HILL COUNTRY BEFORE LIFTING NE.

MEDIUM RANGE MODELS ARE GAINING MOMENTUM ON FORECASTING A SIGNIFICANT
FRONT AND MUCH COOLER AIR FOR THIS WEEKEND. THE GFS AND ECMWF ARE
CONVERGING TOWARD A DELAYED SOLUTION WITH THE STRENGTH AND TIMING
OF THE GFS FRONT LOOKING MORE REASONABLE FOR THIS FORECAST CYCLE.
THE DGEX WENT FROM A MODERATE PATTERN YESTERDAY TO A STRONG FRONT
AND POSSIBLE FREEZE FOR THIS WEEKEND...SO THE SLIGHTLY LESS COOL
TEMPERATURES OF THE GFS IS PREFERRED OVER THE MILDER ECMWF. A
BRIEF PERIOD OF LIGHT OVERUNNING COULD GENERATE LIGHT SHOWERS
LATE FRIDAY...BUT THE DRY AIR PUSH FROM THE NORTH SHOULD LOWER
RAIN CHANCES ONCE THE FRONTAL INVERSION IS SUFFICIENTLY DEEP. POPS
COVER A BROADER RANGE OF TIME FROM EARLY FRIDAY TO EARLY SATURDAY
TO ACCOUNT FOR TIMING UNCERTAINTIES.

[Ntxw]

So we're all wondering what the models say today? Well certainly the typical battles we see! The cold front is now a when though, blue norther coming this next weekend towards Halloween. Widespread frost and freezes likely for North, Central, and the typical cold spots in SE Texas. We'll have to watch the front moving sooner timing since this air mass is very dense and deep. It might even try to snow in the high plains of the panhandle and west Texas since a lot of lagging vorticity will remain at the base of the trough.

GFS went from very cold to cold
Euro and Canadian have flopped from slightly cold to very cold.

[vbhoutex]

If the GFS were to verify it looks like the whole state of Texas will be in for a cool weekend! GFS Ensembles Mean has below normal temperatures in the range of 12-18 degrees Fahrenheit. ECMWF has the front a bit later and not as strong as the GFS tho..

12zGFS Ensembles Temperature Anomalies for Saturday
http://i61.photobucket.com/albums/h62/c ... -13/D7.gif


12zGFS Ensembles Temperature Anomalies for Sunday
http://i61.photobucket.com/albums/h62/c ... -13/D8.gif

If I am reading those maps right it appears to me that we could have some 30's in the Northern Houston metro area with low to mid 40's all over the region.

[Ntxw]

FW discussions this afternoon on the warm week and changes at the end of the period


BIG CHANGES ARE ON THE WAY BY THE END OF THE WEEK. A VERY COLD
AIRMASS WILL BE DEVELOPING AND INTENSIFYING OVER ALASKA AND
WESTERN CANADA DURING THE NEXT FEW DAYS. MODEL GUIDANCE IS IN
AGREEMENT THAT THE LARGE TROUGH OVER THE WESTERN CONTINENT WILL
BEGIN TO MOVE EAST BY THURSDAY WHICH WILL ALLOW THE COLD AIR TO
POUR SOUTHWARD INTO THE PLAINS. MODELS BEGIN TO DIVERGE WITH HOW
DEEP THE TROUGH DIGS AND HOW FAST IT MOVES EAST. THE GFS IS THE
WEAKEST WITH THE UPPER TROUGH AND THEREFORE IS THE SLOWEST AND
WARMEST WITH THE FRONT. THE CANADIAN IS THE MOST AGGRESSIVE AND
SHOWS 850MB TEMPS OF -8C BY THE WEEKEND...WHICH WOULD CERTAINLY BE
RECORD COLD AND WIDESPREAD FREEZING CONDITIONS. THE ECMWF/UKMET
ARE IN BETWEEN THE TWO EXTREMES AND THUS WILL BE FOLLOWED FOR
TIMING AND STRENGTH. EXPECT THE FRONT TO ARRIVE ON FRIDAY...WHICH
MAKES HIGHS FRIDAY DIFFICULT AS TEMPS WOULD END UP FALLING DURING
THE DAY. EXPECT A CHANCE OF RAIN MAINLY BEHIND THE FRONT...BUT
OVERALL NOT EXPECTING A WIDESPREAD OR GOOD RAIN EVENT AT THIS
TIME. LIGHT RAIN AND CLOUDS MAY LINGER INTO SATURDAY BEFORE SKIES
CLEAR. LOWS FRIDAY NIGHT WILL BE IN THE 40S. HIGHS SATURDAY ARE
DEPENDENT ON THE DEGREE OF POST-FRONTAL RAIN...AND MAY END UP
STRUGGLING TO REACH THE MID 50S. AS SKIES CLEAR...SOME LOCATIONS
MAY FLIRT WITH FREEZING SATURDAY NIGHT AND/OR SUNDAY NIGHT AS THE
SURFACE HIGH BUILDING IN.

[weatherrabbit_tx]

If the GFS were to verify it looks like the whole state of Texas will be in for a cool weekend! GFS Ensembles Mean has below normal temperatures in the range of 12-18 degrees Fahrenheit. ECMWF has the front a bit later and not as strong as the GFS tho..

12zGFS Ensembles Temperature Anomalies for Saturday
http://i61.photobucket.com/albums/h62/c ... -13/D7.gif


12zGFS Ensembles Temperature Anomalies for Sunday
http://i61.photobucket.com/albums/h62/c ... -13/D8.gif

If I am reading those maps right it appears to me that we could have some 30's in the Northern Houston metro area with low to mid 40's all over the region

sweet! me likey!!

[TeamPlayersBlue]

Well the next few weeks got even a little more interesting with the emergence of Sandy for the East Coast. Also, remember the squirrel i told you about that i hadnt seen yet? Been busy as a bee all weekend. Running all over the roof this morning. He's back!

[Portastorm]

The Portastorm Weather Center is going out on a limb ... some four days prior to frontal passage ... to say that the currently forecasted temps for this weekend for the Austin area will bust. PWC mets say look for temps to be colder. Doesn't get out of 50s on Saturday. Word!

Models have trouble forecasting shallow cold airmasses for south central Texas this far out.

[Terri]

Well good. It is disgustingly hot and humid right now.

[weatherdude1108]

No kidding! It feels like late Spring out there. Maybe we need a temporary Spring thread until the 50s get here.

[Ntxw]

Looks like the front will arrive sometime Thurs night for DFW. Temps should fall or hold steady most of Friday into the 40s with light rain getting into the 30s by Sat morning and struggle to get over 50. Sunday should remain unseasonably cool. If the Canadian and Euro are correct Sunday could be a large expanse of frost and freezes especially outside of the immediate Urban areas.

For Austin and Houston much of the same story. Frontal passage Friday midday or afternoon with falling temps into the 40s by night and remain cloudy all day with drizzle possible Sat into the mid 50s. 30s Sunday morning in the cold spots frost and freezes here too possible especially hill country if models are off. Will be a quick moving front unlike the last big one.

Rain could be in the picture on Halloween night for many of us so keep an eye.

Edit: Tireman4 asked about the 27th for a race event? If so expect damp and brisk/chilly conditions.

[TeamPlayersBlue]

Dont want to get off topic too much but im sure you guys have seen the perfect storm scenario the Euro has been drawing up the last few days. Holy Moly.