Texas Winter 2013-2014

[TheProfessor]

There's a big difference between model forecasts 2 weeks out vs. 2 days out. From 2-3 days before an event, model trends will provide good insight into what will happen. Sometimes, though, it's just a matter of a degree or two at the surface or aloft that makes all the difference. In such cases, models are less useful even from a day out. The problem I see in the D-FW area is lack of moisture Thu/Fri. Model soundings indicate an airmass well below freezing from the surface up, but quite dry air aloft.

Any chance that the rain we got today helps keep the atmosphere a little more moist?

[ndale]

It has gotten quite, the crazy computer runs must have stunned everyone into silence.

[Portastorm]

It has gotten quite, the crazy computer runs must have stunned everyone into silence.

They've taken a dramatic turn in the last 12 hours. It will be interesting to see if the 12z guidance continues the trend.

The WPC in its early morning model diagnostic discussion speaks to this:


...LOW CLOSING OFF OVER THE NORTHWEST EARLY FRI/TROUGH OVER THE
WESTERN U.S....

PREFERENCE: GFS/ECMWF COMPROMISE...GEFSMEAN
CONFIDENCE: BELOW AVERAGE

00Z GFS/UKMET/CANADIAN GLOBAL HAVE ALL MADE A MARKED TREND TOWARD
A MORE SHEARED/NORTHERLY LOW OVER THE NORTHWEST BY EARLY MON. THE
NAM MADE A SIMILAR TREND...BUT NOT TO THE SAME DEGREE...LEAVING IT
MORE IN LINE WITH THE 12Z GUIDANCE. THE 00Z ECMWF HAS CONTINUED
THIS NORTHERLY TREND...MORE SO THAN THE NAM...BUT LESS THAN THE
GFS/UKMET/CANADIAN GLOBAL. THE 00Z GEFSMEAN HAS ALSO TRENDED
FURTHER TO THE NORTH...BUT IS FURTHER TO THE SOUTH THAN THE GFS.
IN ADDITION TO THE SPREAD...CONFIDENCE IS FURTHER LIMITED BY THE
FACT THAT A KEY PLAYER IN THE EVOLUTION OF THIS SYSTEM IS ENERGY
DROPPING IN FROM WELL TO THE NORTH OVER THE POORLY SAMPLED POLAR
REGION...SUGGESTING FURTHER RUN-TO-RUN DISCONTINUITIES MAY BE IN
STORE. WITH LIMITED CONFIDENCE...SUGGEST A COMPROMISE ON DAY 3
BETWEEN THE GFS/ECMWF...SIMILAR TO THE GEFSMEAN. FURTHER TO THE
SOUTH ACROSS CA INTO THE SOUTHWEST THE FORECAST IS EQUALLY MURKY
WITH THE MODELS SHOWING A FAIR AMOUNT OF SPREAD/DIVERGING TRENDS
WITH THE TIMING/AMPLITUDE OF THE ENERGY DIGGING INTO THE REGION ON
DAY 3. HERE TOO A COMPROMISE BETWEEN THE GFS/ECMWF MAY BE IN
ORDER...AT LEAST UNTIL THE GUIDANCE BEGINS TO SHOW A MORE
CONSISTENT TREND.

[gpsnowman]

It has gotten quite, the crazy computer runs must have stunned everyone into silence.

Silent and sick. Just read NWSAFD from Cavanaugh, great as usual, but I think I am ready to raise the white flag. Not looking promising for a good snow. Zonal flow kicks in next week which is something wxman57 touched on earlier. Hope this is wrong of coarse but winter is slowly fading into spring starting next week.

[Portastorm]

WPC still thinks a wide swath of light freezing precip will be occurring later on Thursday into Friday morning from south central Texas up into northeast Texas. The color guide bar on the left indicates the likelihood (by percentile) of at least .01 inches of freezing precip to occur in a given location.




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[gboudx]

From jeff:

A series of storm systems will move across the state over the next 7 days bringing fairly rapid daily changes to the weather.

Currently a warm front is approaching the upper TX coast with sea fog noted at oil rigs off both the TX and LA coasts. Warm front may reach to near the coastal counties by late morning, but do not expect much if any penetration of the boundary. North of the boundary widespread light rain, drizzle, and fog is ongoing with a cool air mass locked in place due to coastal troughing located off Matagorda Bay. This is resulting in NE winds being overrun by southerly winds just above the surface and the widespread clouds and drizzle. Upper level system ejecting out of the southern Rockies into the central plains currently with the main forcing for ascent located from NE TX into OK and AR where the greatest and heaviest precipitation is occurring. Expect to see current weather continue through early after followed by rapid clearing from the west this evening as a cold front sweeps across the area. Rainfall amounts today will again be on the light side with most locations between .10 and .20 of an inch.

Wednesday-Saturday:
Fresh arctic air mass moves into the area tonight into Wednesday. Gusty north winds will transport cold air across the snow covered plains southward into TX. Highs on Wednesday even under mostly sunny skies will struggle into the 50’s. Fast upper level flow gives little break in the clouds and light rain chances with the next system already approaching the state by Thursday morning. Yesterday this late week storm system looked more compact and potent as a single storm system….today things are looking different with a mean trough over the area and several disturbances rotating through this trough resulting in a prolonged period of clouds and light rainfall from Thursday through Saturday. Forecast models have been trending drier and drier with this late week weather pattern and rainfall amounts are currently looking on the low side (.05 to .25 of an inch). As for temperatures, critical period appears to be Friday morning with surface temperatures falling into the low to mid 30’s. Current thinking is that while it is possible for a few locations to fall below freezing over parts of the area, temperatures will be warm enough to keep everything liquid. Additionally, given the expected very light rain/drizzle I am not sure we will even see falling precipitation when the air temperature is near the freezing mark. Forecast profiles indicate a significant warm layer in the mid levels with a shallow cold layer near the surface which would support freezing rain over any other precipitation only if the surface temperature is below freezing and at this point this is looking fairly unlikely. There is still a fair amount of uncertainty in this part of the forecast so some changes will be possible toward the end of the week into the weekend.

Climate:
All top four climate sites (CLL, IAH, HOU, GLS) have currently recorded their top 10 coolest low temperatures for the period from November 1 to January 31. Low temperatures departures for this period are running 4.0-4.6 degrees below normal across the area…so indeed this winter has been cold. High temperatures for this same period are running 2.5-3.6 degrees below normal.

Also of interest has been the number of days below freezing for morning lows. All four top climate sites have already passed their average number of daily freezes (Oct –Mar).

IAH:
12.5 (average)
16 (2013-2014)

CLL:
17.7 (average)
21 (2013-2014)

GLS:
2.3 (average)
4 (2013-2014)

[Portastorm]

Important to point out to folks that the above is a forecast note issued by Jeff Lindner, who is a meteorologist for the Harris County Flood Control District. Jeff is also a Storm2k member. Jeff forecasts for the southeast Texas area and will, on occasion, opine about weather in other parts of the state. The forecast above is only in reference to southeast Texas.

[Ntxw]

Watching this thread for a while shows that people seem to focus too much on long range models. I'm not sure what most people consider a verification or a bust, but I don't see much verification.

A couple of weeks back, people were posting models showing record cold and snowfall from TX to the northeast states for early February. Now that we're in that time period, forecasts are only showing moderate cold and average precip, nothing extraordinary at all.

I still maintain that any forecast beyond 72-96 hours is untrustworthy. It may hold true, but things can change too easily.

Crikey, sometimes even the 24 hour forecast isn't completely accurate.

Please don't "assume anything." First of all I don't recall anyone posting any map saying record cold and snow was coming to the US. If there was please feel free to post. There were numerous posts from well seasoned posters saying below to well below average departures as well as snow cover extending far to the south for February. Have you not checked the snow cover map lately? There is a disclaimer hence you read the posts at your own risks. If you don't believe we should talk about it, you don't have to read it. It's not a requirement .

[Ntxw]

IAH:
12.5 (average)
16 (2013-2014)

CLL:
17.7 (average)
21 (2013-2014)

GLS:
2.3 (average)
4 (2013-2014)

If anyone has information regarding the records for freezes a season in SE TX, I'd appreciate it if you could help out. I've been trying to dig for it but it seems HGX doesn't make it easy! GRR

[TheProfessor]

Any hope from the 6z GFS

[Portastorm]

Any hope from the 6z GFS

What do you think? Is there?

[gboudx]

Please don't "assume anything." First of all I don't recall anyone posting any map saying record cold and snow was coming to the US. If there was please feel free to post. There were numerous posts from well seasoned posters saying below to well below average departures as well as snow cover extending far to the south for February. Have you not checked the snow cover map lately? There is a disclaimer hence you read the posts at your own risks. If you don't believe we should talk about it, you don't have to read it. It's not a requirement .

To be fair, there have been maps posted that showed lots of snowfall in the timeframe WeatherGuesser mentioned for areas of Texas. And even you had posted comparison ensemble graphics from 1899 to what was being shown for this time period. You didn't say this would definitely happen, but you did post the graphic. I've seen many times over the years where some posters will take a graphic and run with it; be it Winter weather or a hurricane. So maybe some were getting their hopes up based on that, which is really on them and not on the person posting the graphics. The disclaimer is used for a reason, but so are warnings provided in everyday life and lots of people don't read or heed those.

[Ntxw]

To be fair, there have been maps posted that showed lots of snowfall in the timeframe WeatherGuesser mentioned for areas of Texas. And even you had posted comparison ensemble graphics from 1899 to what was being shown for this time period. You didn't say this would definitely happen, but you did post the graphic. I've seen many times over the years where some posters will take a graphic and run with it; be it Winter weather or a hurricane. So maybe some were getting their hopes up based on that, which is really on them and not on the person posting the graphics. The disclaimer is used for a reason, but so are warnings provided in everyday life and lots of people don't read or heed those.

I said that was a FUN segment not a prediction over and over again. I thought I made that clear? This is why we get a bad rap because people seemingly put blame because they don't read wholeheartedly and just want to remember in context.

[Portastorm]

To be fair, there have been maps posted that showed lots of snowfall in the timeframe WeatherGuesser mentioned for areas of Texas. And even you had posted comparison ensemble graphics from 1899 to what was being shown for this time period. You didn't say this would definitely happen, but you did post the graphic. I've seen many times over the years where some posters will take a graphic and run with it; be it Winter weather or a hurricane. So maybe some were getting their hopes up based on that, which is really on them and not on the person posting the graphics. The disclaimer is used for a reason, but so are warnings provided in everyday life and lots of people don't read or heed those.

I said that was a FUN segment not a prediction. I thought I made that clear? This is why we get a bad rap because people seemingly put blame because they don't read wholeheartedly and just want to remember in context.

I think you're both right. And that is the key, isn't it? Folks don't read closely enough sometimes. The assumption is made that if you're posting maps from 1899 and talking about similarities to the current situation, some people will think that you're saying it will be 1899 all over again. Even when you're not saying that!

Good discussion, folks.

[TexasStorm]

Any hope from the 6z GFS

Cold temps and bone dry on the 06Z. 06Z has Dallas under freezing for quite a long time but no moisture.

[gboudx]

To be fair, there have been maps posted that showed lots of snowfall in the timeframe WeatherGuesser mentioned for areas of Texas. And even you had posted comparison ensemble graphics from 1899 to what was being shown for this time period. You didn't say this would definitely happen, but you did post the graphic. I've seen many times over the years where some posters will take a graphic and run with it; be it Winter weather or a hurricane. So maybe some were getting their hopes up based on that, which is really on them and not on the person posting the graphics. The disclaimer is used for a reason, but so are warnings provided in everyday life and lots of people don't read or heed those.

I said that was a FUN segment not a prediction over and over again. I thought I made that clear? This is why we get a bad rap because people seemingly put blame because they don't read wholeheartedly and just want to remember in context.

I agree with you, but I'm just showing where this discussion could be resulting from. And like I said, it's on the reader if they read more into it than what was intended and even pointed out by the author. It's usually a losing proposition to buy into long-term models, except in Summer when it forecasts hot and dry. This is why I never, ever buy into any wintry precip event until I see it falling, and it's why you won't see me post about getting hopes up for anything more than 5 minutes out.

[Ntxw]

The -EPO just went over 2SD's on the daily values. There seems to be a discrepancy between the wxbell charts and the daily's. Weatherbell says we should have peaked around the 25th of January yet the daily's are saying we are heading for the lowest peak now and the 25th didn't even reach -200s on the daily's., one of them has got to be off.

[wxman57]

With the passage of this week without any significant sleet or snow in Houston, I think I'm ready to call "winter over" for Houston in terms of any decent chance of seeing measurable snow. Long-range models (deterministic and ensembles) agree on a gradual pattern change that will shunt all cold air coming across the Pole west of Alaska with a big upper low developing in the northern Gulf of Alaska into southern Alaska. With that kind of flow pattern it's quite unlikely we'll have any more winter weather events in Houston. Of course, a stray sleet pellet may still be possible, but that is about it.

Days are increasing in length by over 1 1/2 minutes each day now, and the sun angle is increasing by about 0.35 deg/day. March will be here before we know it.

P.S. I didn't see my shadow on Sunday

[TheProfessor]

Any hope from the 6z GFS

What do you think? Is there?

Nope. 6z Nam has little hope as well. I hope they are wrong, otherwise it's going to be another wasted cold spell. Maybe severe storm season can start early this year.

[Ntxw]

P.S. I didn't see my shadow on Sunday

You may like this jamstec forecast for spring (and summer). However it's been wrong quite often the past 2 years so, but of course you choose to believe it right?

http://www.jamstec.go...