Texas Winter 2011-2012...

[austinrunner]

As others have noted there is just not enough arctic air in western Canada to effect us here in NTX. Until the ridge returns and polor air gets dumped in to NW Canada expect a mild/cool pattern across the southern U.S.

That's not the only possible source for arctic air in Texas. Another source is north central Canada.

[Ntxw]

Current Temperatures in Canada.



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[Snowshoe]

Well when does it look like our next chance for cold and winter weather is? Two or three weeks?

[Ntxw]

Well when does it look like our next chance for cold and winter weather is? Two or three weeks?

It's hard to tell, volatility is incredible right now. Just two days ago you had warmth galore from most of the models. Now you have the Euro going cold for several runs and canadian just flipping. The differences between the Euro and GFS are massive at such a relatively close range...I'd hate to be anyone who has to predict the weather the next 7 days professionally.

Edit: 12z euro continues it's march to an arctic outbreak. -10c line down to Houston at 850mb about a week from today.

[Portastorm]

As others have noted there is just not enough arctic air in western Canada to effect us here in NTX. Until the ridge returns and polor air gets dumped in to NW Canada expect a mild/cool pattern across the southern U.S.

That's not the only possible source for arctic air in Texas. Another source is north central Canada.

True although the vast majority of the time, our polar/Arctic air comes from western Canada into Montana and the lee side of the Rockies. For us to get air from north central Canada, it would almost have to be a backdoor front or a full latitude trough with a north to south direct flow.

[iorange55]

Wow! The GFS and Euro really are disagreeing, Holy Banana bread! That is a big difference, GFS has mild weather and the Euro has some bone chilling cold.

That is crazy that they are so far apart with only a week to go.

[Snowshoe]

Hopefully we get some cold!!!

[Portastorm]

Yeah Ntxw ... get a load of that 12z Euro run! A 1056mb high coming down the Rockies?! That is a true Arctic outbreak.

http://www.meteo.psu.edu/~gadomski/ECMWF_12z/ecmwfloop.html

[Ntxw]

Yeah Ntxw ... get a load of that 12z Euro run! A 1056mb high coming down the Rockies?! That is a true Arctic outbreak.

http://www.meteo.psu.edu/~gadomski/ECMWF_12z/ecmwfloop.html

The ridge that it shoots up into western Canada is mind boggling. Could it be the rubber band snap everyone is waiting for?! For sure if this was true the east coast will certainly be in a for a blizzard.



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[austinrunner]

As others have noted there is just not enough arctic air in western Canada to effect us here in NTX. Until the ridge returns and polor air gets dumped in to NW Canada expect a mild/cool pattern across the southern U.S.

That's not the only possible source for arctic air in Texas. Another source is north central Canada.

True although the vast majority of the time, our polar/Arctic air comes from western Canada into Montana and the lee side of the Rockies. For us to get air from north central Canada, it would almost have to be a backdoor front or a full latitude trough with a north to south direct flow.

That's about what the ECMWF is predicting will happen next week.

[cycloneye]

Here are more graphics of the 12z Euro despicting a biggie for East Coast with Texas getting very cold.

[wxman57]

Definitely NOT an Arctic outbreak indicated by the European. The flow is off the Gulf of Alaska into British Columbia then southward into the U.S. I'm looking at the surface temperature anomaly maps and it's forecasting temps 20F-30F above normal in western Canada through next week. It develops the high center over the U.S., it doesn't bring any really cold air down from the Arctic. Checking its projected surface temps, it's only forecasting a low of around 30F in Houston for next Wednesday (mid to upper 20s in Dallas) as the coldest morning. Certainly nothing out of the ordinary and not too different from what it forecast for Texas temps a week ago valid today/tomorrow. It was too cold on that forecast and it may be too cold for next week.

In contrast, GFS has low temps in the mid 50s along the upper TX coast for next Wed, about 20 deg warmer. There's definitely a difference between the two, but there's no Arctic air involved.

[Portastorm]

Definitely NOT an Arctic outbreak indicated by the European. The flow is off the Gulf of Alaska into British Columbia then southward into the U.S. I'm looking at the surface temperature anomaly maps and it's forecasting temps 20F-30F above normal in western Canada through next week. It develops the high center over the U.S., it doesn't bring any really cold air down from the Arctic. Checking its projected surface temps, it's only forecasting a low of around 30F in Houston for next Wednesday (mid to upper 20s in Dallas) as the coldest morning. Certainly nothing out of the ordinary and not too different from what it forecast for Texas temps a week ago valid today/tomorrow. It was too cold on that forecast and it may be too cold for next week.

In contrast, GFS has low temps in the mid 50s along the upper TX coast for next Wed, about 20 deg warmer. There's definitely a difference between the two, but there's no Arctic air involved.

The 500mb flow is almost north to south from the Northwest Territories and the 850mb temps @ 168 hours over the northeast quarter of the state are like -12 to -14. I don't know ... you're the pro and I'm not but that seems to me to be more than your garden variety cold front. But I get it ... you don't buy the Euro.

[wxman57]

The 500mb flow is almost north to south from the Northwest Territories and the 850mb temps @ 168 hours over the northeast quarter of the state are like -12 to -14. I don't know ... you're the pro and I'm not but that seems to me to be more than your garden variety cold front. But I get it ... you don't buy the Euro.

I'm just reporting what the Euro model is forecasting. For the time being, I have access to all the Euro model data (for a change). The "problem" is the source region is just not that cold (15-25F above normal in west and NW Canada). Yeah, it's colder than we are now by a good bit, but it's not really that cold for Canada. If the Euro is correct, then we could see a strong cold front move through Sunday night with strong northerly winds Monday and temps maybe into the low-mid 50s for highs (which is what the 12Z Euro is forecasting). Could even be a light freeze by Wednesday morning (30-32F). But I suspect the Euro may be a bit TOO cold with its forecast for next week, as it was last week in its forecasts for the current time period.

[TeamPlayersBlue]

Holy Euro, is it a bit much to ask for a littl bit of a -NAO or some Blocking to go with it

How can the 850 temp be -10C i Houston with lows around 30F? Would this be due to a lack of cloud cover?

[wxman57]

Holy Euro, is it a bit much to ask for a littl bit of a -NAO or some Blocking to go with it

How can the 850 temp be -10C i Houston with lows around 30F? Would this be due to a lack of cloud cover?

Hey, don't shoot the messenger! I'm just reporting the figures off the 12Z Euro run. It actually forecasts -13C at 850mb on Tuesday afternoon with an 18Z temp of 39F at IAH, 36 at 6pm, 32 at midnight next Tuesday, then 29-30 at IAH at 12Z Wednesday.

[Ntxw]

We might be getting some help from the MJO eventually. It's been a little flippy with forecasting it lately, but it's trending away from phase 5 and begins the magical roll (though weak so far) to the 6, 7, 8 range.



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[CaptinCrunch]

As others have noted there is just not enough arctic air in western Canada to effect us here in NTX. Until the ridge returns and polor air gets dumped in to NW Canada expect a mild/cool pattern across the southern U.S.

That's not the only possible source for arctic air in Texas. Another source is north central Canada.

True although the vast majority of the time, our polar/Arctic air comes from western Canada into Montana and the lee side of the Rockies. For us to get air from north central Canada, it would almost have to be a backdoor front or a full latitude trough with a north to south direct flow.

Or a rex block over greenland, that would dump arctic air from central Canada almost due south.

[Texas Snowman]

@WFAAWeather tweets: "Balmy weather prevails through the end of the year, and not long afterwards, COLD SNAP."

Looks like they're buying into the EURO.

Noticed a Little Rock station tweeted this afternoon about the difference between EURO and GFS. "@FOX16@Weather: European model is giving us a huge blast of arctic air the day after New Year's. The GFS model gives us mild air in the 50's...geesh."

[Ntxw]

FW gives their two cents on today's runs.

IN THE EXTENDED...THE GFS HAS BEEN VERY
INCONSISTENT...FORECASTING A COLD FROPA THAT HAS CHANGED FROM
MONDAY TO SATURDAY TO SUNDAY OVER THE LAST 36 HOURS OF RUNS.
TODAY/S 12Z RUN FORECASTS THE FROPA FOR SATURDAY EVENING...AND
HAS THE FRONT QUITE WEAK. IN CONTRAST...THE ECMWF AND CANADIAN
MODELS HAVE BEEN CONSISTENT...OVER THE LAST COUPLE OF DAYS...IN
DEVELOPING A HIGH AMPLITUDE RIDGE OVER THE WESTERN U.S. AND
DROPPING A DEEP TROF/STRONG COLD FRONT INTO THE PLAINS ON SUNDAY.
THE SUNDAY COLD FRONT HAS VERY COLD CANADIAN AIR BEHIND IT IN THE
CMC/ECMWF AS WELL. GIVEN THE POOR EXTENDED FORECAST TRACK RECORD
OF THE GFS OVER THE LAST FEW WEEKS...I AM GOING TO USE THE
CMC/ECMWF SOLUTION AND HAVE FORECAST A COLD OUTBREAK SUNDAY
THROUGH WEDNESDAY. IF I WERE TO PERFECT PROG THE ECMWF...I WOULD
HAVE DROPPED WEDNESDAY LOW TEMPERATURES INTO THE LOW 20S ACROSS
MUCH OF THE AREA...BUT OPTED FOR LOWS ABOUT 5 DEGREES HIGHER
EXPECTING THE AIRMASS TO MODIFY A BIT AS IT HEADS SOUTH. IF THIS
SYSTEM PROVES TO BE STRONGER/COLDER...LOWS COULD DIP INTO THE
TEENS BY MID WEEK.

ON SUNDAY...MOISTURE APPEARS TO BE LIMITED ACROSS WESTERN NORTH
TEXAS...SO ONLY FORECAST LOW POPS IN THE EASTERN HALF FOR SUNDAY
AFTERNOON AND EVENING. DUE TO THE DRY AIR BEHIND THE FRONT...ANY
PRECIP SHOULD SHUT OFF RAPIDLY...LONG BEFORE THE TEMPERATURES
DROP BELOW FREEZING. AT THIS TIME I DO NOT EXPECT WINTER PRECIP
WITH THIS SYSTEM.

THIS IS A VERY INTERESTING CHANGE IN THE PATTERN...AND NOT
UNUSUAL FOR JANUARY OR FOR LA NINA WINTERS. ALTHOUGH THE SOLUTION
WILL LIKELY NOT BE EXACTLY WHAT IS FORECAST TODAY...IT IS
CERTAINLY A SIGNIFICANT CHANGE AND IT WILL BE INTERESTING TO SEE
HOW IT PLAYS OUT. 84