Texas winter wx thread (2009-2010)

[gboudx]

Wow CBS 11 here in Dallas is pretty bold with the forecast next week.

http://weather.cbs11tv.com/US/TX/Dallas.html

It's not really that bold. The NWS mentioned it in the morning AFD.

IF THE CURRENT GFS SOLUTION MATERIALIZES...ANOTHER ROUND OF PRECIPITATION AND POSSIBLY
SNOW WILL ARRIVE TUES NIGHT/WEDNESDAY.

[HockeyTx82]

Wow CBS 11 here in Dallas is pretty bold with the forecast next week.

http://weather.cbs11tv.com/US/TX/Dallas.html

It's not really that bold. The NWS mentioned it in the morning AFD.

IF THE CURRENT GFS SOLUTION MATERIALIZES...ANOTHER ROUND OF PRECIPITATION AND POSSIBLY
SNOW WILL ARRIVE TUES NIGHT/WEDNESDAY.

True, but on the NWS website if you look at the extended forecast they only mention rain for now. We shall see who changes over the next few days.

[iorange55]

Wow CBS 11 here in Dallas is pretty bold with the forecast next week.

http://weather.cbs11tv.com/US/TX/Dallas.html

It's not really that bold. The NWS mentioned it in the morning AFD.

IF THE CURRENT GFS SOLUTION MATERIALIZES...ANOTHER ROUND OF PRECIPITATION AND POSSIBLY
SNOW WILL ARRIVE TUES NIGHT/WEDNESDAY.

New GFS looks like it's trending towards a possible storm next week like the other models, and this one looks to have a lot of moisture with it. Still too early to get excited, though.

This is interesting GFS 12




I imagine it's still too warm with that cold front, so if any of that falls as snow, sleet or freezing rain here in dallas that would be a pretty big storm.

[gboudx]

True, but on the NWS website if you look at the extended forecast they only mention rain for now. We shall see who changes over the next few days.

I hear ya. I never look at their extended forecasts because they are usually conservatives in those. But the AFD's give some insight into what they might be thinking for the extended, and how it may change from the "official" forecast.

[snow and ice]

Wow CBS 11 here in Dallas is pretty bold with the forecast next week.

http://weather.cbs11tv.com/US/TX/Dallas.html

It's not really that bold. The NWS mentioned it in the morning AFD.

IF THE CURRENT GFS SOLUTION MATERIALIZES...ANOTHER ROUND OF PRECIPITATION AND POSSIBLY
SNOW WILL ARRIVE TUES NIGHT/WEDNESDAY.

New GFS looks like it's trending towards a possible storm next week like the other models, and this one looks to have a lot of moisture with it. Still too early to get excited, though.

This is interesting GFS 12




I imagine it's still too warm with that cold front, so if any of that falls as snow, sleet or freezing rain here in dallas that would be a pretty big storm.

Big Ticket item next week for Texas and Oklahoma and on a large scale. GFS is not handling the cold air well. The arctic air will be a lot further south than it is now indicating. By the end of this weekend-early next week, there will be talk of a major winter storm in the southern plains and Texas.

[wxgirl69]

Can we start a thread for next week... It's getting kinda confusing trying to figure who is talking about this Friday and who is talking about next week. Thanks

[gboudx]

Can we start a thread for next week... It's getting kinda confusing trying to figure who is talking about this Friday and who is talking about next week. Thanks

The DFW folks are talking about next week. The ATX and HTX folks are talking about tomorrow.

[jasons2k]

Big Ticket item next week for Texas and Oklahoma and on a large scale. GFS is not handling the cold air well. The arctic air will be a lot further south than it is now indicating. By the end of this weekend-early next week, there will be talk of a major winter storm in the southern plains and Texas.

True, the GFS does not handle shallow cold airmasses well and they typically plunge to the south faster than modelled.

But the model is also indicating a low pressure center along the front. With such a setup, the cold air would dump around the backside of the low - meaning - the cold air may be temporarily held-up in the OK/TX Panhandles until that low passes off to the east...then the cold air would quickly surge southward.

[Portastorm]

Oh how I hope Henry Marguisty from Accuweather is right about this!

[double D]

Big Ticket item next week for Texas and Oklahoma and on a large scale. GFS is not handling the cold air well. The arctic air will be a lot further south than it is now indicating. By the end of this weekend-early next week, there will be talk of a major winter storm in the southern plains and Texas.

True, the GFS does not handle shallow cold airmasses well and they typically plunge to the south faster than modelled.

But the model is also indicating a low pressure center along the front. With such a setup, the cold air would dump around the backside of the low - meaning - the cold air may be temporarily held-up in the OK/TX Panhandles until that low passes off to the east...then the cold air would quickly surge southward.

That's why it's so hard to get snow in the southern 2/3 of the state. Once it's cold enough to snow, the moisture is gone.

[richtrav]

One Question. I live in Deep South Texas in Harlingen about 350 Miles South Of Houston. I am seeing the models of both the NAM and GFS and they are showing the freeze line coming this far south. Am I seeing this correct and do you think we have a chance for frozen stuff. I live in Harlingen and they have a 20% Chance of Rain Low of 33. What do you all think?

No, temps look to be in the 40s right now when the rain hits (the NWS has a 70% chance, not 20). If it does get as cold as they're progging it would probably have to involve some amount of clearing Sat morning after the precip has passed by. You're asking for a tall order; it just got through snowing down here in '04, so extrapolating we're due for our next event around 2113.

[snow and ice]

Big Ticket item next week for Texas and Oklahoma and on a large scale. GFS is not handling the cold air well. The arctic air will be a lot further south than it is now indicating. By the end of this weekend-early next week, there will be talk of a major winter storm in the southern plains and Texas.

True, the GFS does not handle shallow cold airmasses well and they typically plunge to the south faster than modelled.

But the model is also indicating a low pressure center along the front. With such a setup, the cold air would dump around the backside of the low - meaning - the cold air may be temporarily held-up in the OK/TX Panhandles until that low passes off to the east...then the cold air would quickly surge southward.

By then the cold air will have already made it to the coast. That Panhandle low will eventually be suppressed to southern Texas, as that is where the boundary will be by that time. Then, something will pop in the Northern GOM and track NE, throwing a lot of moisture over a very cold dome of air.

[iorange55]

Winter Weather Advisory up for Austin and San Antonio areas.

...WINTER WEATHER ADVISORY IN EFFECT FROM 6 AM TO 6 PM CST
FRIDAY FOR PORTIONS OF SOUTH CENTRAL TEXAS...

THE NATIONAL WEATHER SERVICE IN AUSTIN/SAN ANTONIO HAS ISSUED A
WINTER WEATHER ADVISORY FOR SNOW...WHICH IS IN EFFECT FROM 6 AM
TO 6 PM CST FRIDAY.

SNOW WILL GENERALLY BE LIGHT ACROSS THE EDWARDS PLATEAU...HILL
COUNTRY AND AUSTIN/SAN ANTONIO CORRIDOR...WHERE ACCUMULATIONS OF A
TRACE UP TO ONE HALF INCH ARE POSSIBLE. AT THIS TIME...SNOW IS NOT
EXPECTED TO ACCUMULATE ON ROADS...BRIDGES OR OVERPASSES ACROSS
THIS AREA.

MODERATE SNOW IS LIKELY ACROSS PORTIONS OF FAYETTE...LAVACA AND
DEWITT COUNTIES WHERE ACCUMULATIONS BETWEEN ONE HALF AND TWO
INCHES ARE POSSIBLE. SNOW MAY ACCUMULATE ON SOME ROADS...BRIDGES
AND OVERPASSES OVER PORTIONS OF THESE THREE COUNTIES AND MAKE
TRAVEL HAZARDOUS.

[snow and ice]

Oh how I hope Henry Marguisty from Accuweather is right about this!

He probably made that map based off a run of the GFS. Those upper level features are very tricky to forecast. Satellite imagery and Radar will tell the final solution. By this time tomorrow, the Austin area will know their fate. I still think that omega block saves the Austin area.

[Ntxw]

LOL snow and ice you sure now how to pull on portastorm's leg

[Jag95]

Hydrological Prediction Center has at least a 10% chance of >4 inches for some areas now.

[double D]

According to the NWS out of Lubbock, light snow is being reported with a temp. of 29 degrees. That's odd because the GFS or NAM predicted no moisture until late tonight and tomorrow morning. Maybe the system is stronger and faster than previously thought

[Portastorm]

LOL snow and ice you sure now how to pull on portastorm's leg

He has for years ...

[jasons2k]

From Jeff:

All models have trended wetter and colder for the Friday event.

Will likely need a Winter Storm Warning for metro Houston and all US 59 corridor counties this afternoon and possible upgrade for the coastal counties also.

Winter Weather Advisory issues for all of C and SC TX.

Discussion:

Moisture advection noted on the visible images out of central Texas moving up the Rio Grande while powerful short wave dips into the southern Rockies. Impressive lift comes to bear over the region starting by mid morning Friday and really cranks into gear by noon. Profiles show a frozen profile all the way down to Hobby and Victoria by noon Friday with a rapid change to all snow north of this line and change to all snow to the coast by mid afternoon. GFS strongly supports a 60-80 mile wide banded heavy snow axis roughly 60 miles either side of US 59 with significant surface accumulations possible. 12Z GFS model pounds the US 59 corridor with 4-6 inches of accumulation. Trend has been a southward shift in the snowfall axis and the heaviest totals may in fact end up over the coastal counties and first inland tier counties. Starting to look very similar to the historic 2004 Christmas Eve event where the moisture near the coast meets the cold air..although not expecting a foot of snow and a version more to the northeast than in 2004.

Accumulations:

Austin to College Station to Huntsville:

Will be lowering totals in this region as focus is shifting southward. A dusting to 2” is possible starting early Friday morning.

Columbus to Conroe to Lake Livingston:

This area should be on the north side of the heavier snow band with accumulations of 1-4 inches possible. Should see onset of snow by early to mid morning with accumulations by late morning as temperatures fall to freezing.

US 59 from Victoria to Liberty Co including metro Houston:

Will be upping accumulations into the 2-4” range across this area including metro Houston with some areas possibly picking up 6”. Will onset snow between 1000am and noon Friday and continue into early evening. May need to add moderate and heavy snow with visibilities tanking to below 1/4th of a mile at times in heavy snow bands. Could see up to 1” per hour of accumulation. Given the possible increased snowfall rates…not only bridges, but surface streets may become issues by Friday afternoon as surface temperatures fall to and below freezing.

Coastal Counties:

Will need to add accumulation to the coastal counties given the latest data with 1-2” likely including the beaches. Will see snow onset before noon in the Victoria area and spread NE up the coast by early afternoon. May need to go even higher on the accumulation in this region if the models continue to trend southward.

Freeze Warning:

Other change was to add a freeze warning to all counties for Friday into mid morning Saturday. Will be lowering temperatures into the mid to upper 20’s by Saturday morning. Freezing and sub-freezing temperatures are expected for 10-12 hours across the region…this will be an advection freeze leading to greater impact to vegetation as ground warmth will be stripped away.

Actions:

TXDOT, Harris County Toll Road Authority, and all county Precincts are applying de-icing agent to area freeways and connector ramps and preparing to sand bridges and overpasses.

Travel will become increasingly hazardous during the day on Friday and should be avoided if possible after snow begins to fall as elevated surfaces glaze over and then accumulate slush.

[jasons2k]

And another update from Jeff:

NWS has expanded the Winter Storm Watch to include all of SE TX including Harris County and metro Houston from 600pm until midnight Friday.

Expect significant snow accumulations along and 30-40 miles either side of US 59 starting by late morning. General accumulations of 1-4” in this zone with isolated totals of 5-6”.

Situation remains in flux and significant changes remain possible with accumulation amounts and location.