Texas winter wx thread (2009-2010)

[Nederlander]

I have a question for anyone that can answer this..my parents live near Lawton, Ok - the last few days they have heard some rumors that they are expecting another MAJOR Ice Storm before the end of Feb. - actually predicting to be worse than they had a couple weeks ago - and my parents were without electricity for 8 days - luckly they have a propane fireplace! They are very concerned and they knew I listened to you guys...any insight?? Thanks in advance!

Still a good ways out but its looking likely that they will get some form of frozen precip.. Models have been sniffing it for days.. Stay tuned.. Pro mets on here are as good as they come..

[Peanut432]

I have a question for anyone that can answer this..my parents live near Lawton, Ok - the last few days they have heard some rumors that they are expecting another MAJOR Ice Storm before the end of Feb. - actually predicting to be worse than they had a couple weeks ago - and my parents were without electricity for 8 days - luckly they have a propane fireplace! They are very concerned and they knew I listened to you guys...any insight?? Thanks in advance!

Still a good ways out but its looking likely that they will get some form of frozen precip.. Models have been sniffing it for days.. Stay tuned.. Pro mets on here are as good as they come..

I live 30 miles northeast of Childress and didn't have power for 3 days. Over 3000 power poles down in SW Oklahoma. 3-4 weeks later and some parts still don't have power. Lots of different power companies from all over still in town. This isn't going to happen again...is it?

[wxman57]

Those maps with the green precip areas behind the freezing lines can be a bit deceiving, as the precip is occurring up to 12 hours prior to the valid time of the map at 192 hrs. I made a couple meteograms for Dallas from that 18Z GFS to show you what I mean.

Here's the 0-180hr part. Nothing significant except lots of cold rain toward the end:


Now the 180-384hr part that got everyone's attention. Look closely. It's 42F at 12AM Friday (26th) and down to 29F by 12PM Friday (12 hours later). That green bar below the 29F at 12PM represents 0.28" liquid precip that falls during the PREVIOUS 12 hours. That means that the heaviest precip was falling when the 18Z GFS was predicting the temperature to be 42F. It's quite possible that the 0.28" precip ended before the temperature dropped to freezing.

Now I'm not saying that there won't be a significant winter precip event across TX/OK next week, just that the 18Z GFS isn't really showing a big storm for Dallas. I'm always a bit wary of a model that first shows a storm this coming Friday, then Mon/Tue then Wed then the NEXT Friday. Always farther along. I don't think the GFS has the right idea yet. We'll have to wait a few more days. There is a lot of cold air coming down next week, we just don't know the details of what will happen and who'll be hit hardest yet.

Here's the 180-384hr GFS meteogram from 18Z:

[gofrogs2]

Whats the 0z gfs saying.

[Ntxw]

Whats the 0z gfs saying.

A lot of NW flow aloft with rain for just about everyone south of Kansas. Warm (relative) alllll the way up to northern Oklahoma (10c isotherm) with no real surge of cold air. Is that believable? Lasting all the way through 300hr +

[Extremeweatherguy]

Wow, the GFS has not been performing well at all in the long range recently!

As an example, take a look at the absolute lack of consistency it has been showing for next Wednesday afternoon over the last four runs..

2/17/10 6z run = http://i43.photobucket.com/albums/e371/ ... n_180m.gif
2/17/10 12z run = http://i43.photobucket.com/albums/e371/ ... n_174m.gif
2/17/10 18z run = http://i43.photobucket.com/albums/e371/ ... n_168m.gif
2/18/10 00z run = http://i43.photobucket.com/albums/e371/ ... n_162m.gif

This is pretty pathetic IMO. We are less than a week out from this point now, so hopefully the GFS will be able to pull it together soon and give us a more definite solution!

[orangeblood]

Wow!!! Canadian showing a Big Winter Storm for Texas starting next Thursday. Next week is all going to depend on the evolution of the upper low hitting the west coast this weekend.

[Ntxw]

If the Canadian were to verify, prolific. To be fair, the EC isn't so adamant about showing a big winter storm in Texas next week.

[Portastorm]

We all know there is considerable divergence now when it comes to computer model solutions for next week and the pattern is giving the models fits, right? With that in mind, you couldn't find two better examples IMHO of a good AFD and a bad AFD out of a NWSFO. Here you go ... first the good one, then the "other" one.

AMARILLO NWSFO snippet
THE NEXT PERIOD OF CONCERN WILL BE TUESDAY. THERE ARE AS MANY
SOLUTIONS TO WHAT WILL HAPPEN TUESDAY AS THERE ARE MODELS AND
ENSEMBLE MEMBERS. THE SOLUTIONS RANGE FROM THE ECMWF SHOWING A SLOW
CUTOFF BAJA LOW BRINGING PLENTY OF PRECIP TO THE REGION...TO A BARELY
NOTICEABLE PROGRESSIVE UPPER LEVEL SHORTWAVE TROUGH WITH THE GFS.
EXPECT THAT THE CONSIDERABLE DIS AGREEMENT COMES FROM THE FACT THAT
UPPER LEVEL SPLIT FLOW DEVELOPS BY MONDAY. CONSIDERING THE
UNCERTAINTY...HAVE KEPT THE FORECAST DRY THROUGH THIS PERIOD.

AUSTIN/SAN ANTONIO NWSFO
AFTER THOSE WET EPISODES...EXPECT PLEASANT WEATHER CONDITIONS FOR
MUCH OF NEXT WEEK WITH ANOTHER FROPA FORECASTED TO SLIGHTLY INCREASE
CHANCES OF SHOWERS ON THURSDAY.

[srainhoutx]

PRELIMINARY EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
329 AM EST THU FEB 18 2010

VALID 12Z MON FEB 22 2010 - 12Z THU FEB 25 2010


USED AN EVEN BLEND OF THE 00Z/18 ECMWF AND 00Z/18 GEFS MEAN FOR
THE PRELIMINARY FRONTS AND PRESSURES FOR DAY 3...WITH MOSTLY GEFS
MEAN THEREAFTER. THE 00Z/17 GFS AND GEM GLOBAL WERE NORTH WITH
THE MAJOR WAVE CROSSING THE EAST DURING THE FIRST HALF OF THE
PERIOD...AND ARE NOW SOUTH...WHILE THE 00Z/17 ECMWF AND UKMET WERE
SOUTH AND ARE NOW NORTH WITH THE SAME FEATURE. THIS FLIP-FLOPPING
ARGUES FOR A MIDDLE OF THE ROAD SOLUTION...WHICH THE HEAVY
EMPHASIS ON THE GEFS MEAN AFFORDS THIS PACKAGE. THE BLOCK OVER
THE WEST IS NO CLEARER...WITH THE POSITION OF THE COLD MID LEVEL
CORES A BIT LIKE THE SHELL SHUFFLE GAME. HOPEFULLY...THE LIBERAL
USE OF THE MEAN WILL MITIGATE ANY LARGE ERRORS THIS PERIOD.

CISCO

[wxman22]

The European looks nice if you want frozen precip over SOUTH CENTRAL and SOUTHEAST Texas...

[Ntxw]

Meanwhile, the GFS continues it's march to absolutely nowhere with yet another different solution...

[txagwxman]

6z GFS has some frozen precip DFW on Tue...these models are a mess this morning.

[txagwxman]

That would get portastorm excited.

[Portastorm]

Admittedly, I had trouble interpreting that UKMET 0z run this morning. It appears to still be showing surface ridging into Texas but still some troughiness out west? Looks to me like the brunt of the coldest air is going to our northeast. But if you're telling me it's something to get excited about ... then I'm excited!

[txagwxman]

:double:

PRELIMINARY EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
329 AM EST THU FEB 18 2010

VALID 12Z MON FEB 22 2010 - 12Z THU FEB 25 2010


USED AN EVEN BLEND OF THE 00Z/18 ECMWF AND 00Z/18 GEFS MEAN FOR
THE PRELIMINARY FRONTS AND PRESSURES FOR DAY 3...WITH MOSTLY GEFS
MEAN THEREAFTER. THE 00Z/17 GFS AND GEM GLOBAL WERE NORTH WITH
THE MAJOR WAVE CROSSING THE EAST DURING THE FIRST HALF OF THE
PERIOD...AND ARE NOW SOUTH...WHILE THE 00Z/17 ECMWF AND UKMET WERE
SOUTH AND ARE NOW NORTH WITH THE SAME FEATURE. THIS FLIP-FLOPPING
ARGUES FOR A MIDDLE OF THE ROAD SOLUTION...WHICH THE HEAVY
EMPHASIS ON THE GEFS MEAN AFFORDS THIS PACKAGE. THE BLOCK OVER
THE WEST IS NO CLEARER...WITH THE POSITION OF THE COLD MID LEVEL
CORES A BIT LIKE THE SHELL SHUFFLE GAME. HOPEFULLY...THE LIBERAL
USE OF THE MEAN WILL MITIGATE ANY LARGE ERRORS THIS PERIOD.

CISCO

What a cop out.

[srainhoutx]

Not too far off from the ECMWF Portastorm.

[txagwxman]

:uarrow:

Admittedly, I had trouble interpreting that UKMET 0z run this morning. It appears to still be showing surface ridging into Texas but still some troughiness out west? Looks to me like the brunt of the coldest air is going to our northeast. But if you're telling me it's something to get excited about ... then I'm excited!

Ridge of high pressure right into Texas with overrunning precip over Austin...it would be light, but it would be something. Still though these models are all over the place this morning.

[srainhoutx]

:double:

PRELIMINARY EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
329 AM EST THU FEB 18 2010

VALID 12Z MON FEB 22 2010 - 12Z THU FEB 25 2010


USED AN EVEN BLEND OF THE 00Z/18 ECMWF AND 00Z/18 GEFS MEAN FOR
THE PRELIMINARY FRONTS AND PRESSURES FOR DAY 3...WITH MOSTLY GEFS
MEAN THEREAFTER. THE 00Z/17 GFS AND GEM GLOBAL WERE NORTH WITH
THE MAJOR WAVE CROSSING THE EAST DURING THE FIRST HALF OF THE
PERIOD...AND ARE NOW SOUTH...WHILE THE 00Z/17 ECMWF AND UKMET WERE
SOUTH AND ARE NOW NORTH WITH THE SAME FEATURE. THIS FLIP-FLOPPING
ARGUES FOR A MIDDLE OF THE ROAD SOLUTION...WHICH THE HEAVY
EMPHASIS ON THE GEFS MEAN AFFORDS THIS PACKAGE. THE BLOCK OVER
THE WEST IS NO CLEARER...WITH THE POSITION OF THE COLD MID LEVEL
CORES A BIT LIKE THE SHELL SHUFFLE GAME. HOPEFULLY...THE LIBERAL
USE OF THE MEAN WILL MITIGATE ANY LARGE ERRORS THIS PERIOD.

CISCO

What a cop out.

[wxman57]

Is that the main GFS operations center above, srain?

I'm not ready to buy anything the GFS is forecasting beyond the next 2-3 days. There is tremendous variability from one run to the next. Remember that "snow event" for Dallas that everyone here (well, some here) got excited about after the 18Z run yesterday? Two runs later at 06Z the lows are in the mid 40s with highs in the 50s for the same time period and little or no precip. I think that the Euro should be watched more closely than the GFS for now. Canadian has not proven to be very good with these winter systems down here.