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jasons

Winter Weather Threat - February 2011

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jasons

Hi all:

I wanted to create this thread, with the correct year, as a continuation to the January thread.

A few weeks ago, I had posted about the models latching-on to a possible outbreak of very cold arctic air spilling down the plains. Although the models were consistent, they were questionable as the cold air that was needed never really built-up in Canada as depicted. It's very common for the GFS to show some scary scenario 10-14 days away but the cold air needed to make it all happen is lacking.

We have had the two fronts come down, and while very chilly, it's nothing record-breaking. Still - it's been below freezing at my house now for about 12 hours so this is not your average run-of-the mill front either. I just point this out to show that while Armageddon did not happen, what has resulted is about what was expected. That is while not anything historical, many of us have seen it quite colder than normal with these two mini-outbreaks. Also, these initial surges have been suspected of 'setting the table' for the real enchilada to come down.

Onto the future:

The models continue to show doomsday-like scenarios in the 10-14 day time period with the 06z GFS depicting a 1983-1989-ish like event. For example, on February 2nd, it shows a NOON temperature in Houston of 18 degrees F. In Dallas - how about 9 degrees at noon and a low of about zero the next morning?

I want to caution again it is very common for the GFS to show scary numbers in the 10-14 days range that never come to fruition. However, caveats aside, this is a situation that we need to watch closely over the next few weeks. I lend more credence to these scenarios now than I have before. Unlike late December, this time the cold air is indeed building-up in Canada and the pattern is conducive for dislodging a chunk of this arctic air and plunge it southward into the US.

So, in summary, we all need to keep a close watch for the possibility of severe cold dumping down in early February. The models don't want to let the scenario go, the pattern is there for it, and now the final missing piece - actual cold air - is now building in Canada. Keep a close watch!

Edited by jasons

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gsytch

STOP NOW! Ban him. Take his priveleges away. Jason, you are no longer allowed to even hint of anything like this AFTER what we've been through here in Tampa Bay :-)). BUt, thanks for the "heads up" as I will pay attention and hope for the better. G~

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_Keith

Jason, are you sure you don't really work at The Suicide Hotline and you're just trying to secretly drum up some business.

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Xenon

18F at noon in Houston...it's the end of the worldcrying.gif

:( Jonathan

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Takil-Explorer

Armagedon again downthere in sunny Texas...

Alexander

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bubba

Jason, Can you post some of the websites where you get this interesting long-term information. I look all over without success. I do see Bastardi is now talking about February vaguely for potential damage control but I cannot locate specifics.

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jasons

Sure thing - there are several good places to look:

I'm a moderator on storm2k.org and we have a pretty active winter weather forum: http://www.storm2k.org/phpbb2/viewforum.php?f=22

I also check out some good discussions on this site (formerly easternuswx): http://www.americanwx.com/bb/index.php?/forum/20-weather-forecasting-and-discussion/

And locally, khou.com has a great forum for the Houston area: http://forums.khou.com/viewforum.php?f=2

Those sites are frequented by pro mets and they have a wealth of information you won't find from the general media outlets.

Just to add - Don Sutherland is a very well respected weather analyst (he's not a degreed Met) and his February thoughts are posted here:

Edited by jasons

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gsytch

Those are great sites. I already joined Storm2K. The models are predicting warmth for FL while the nation as a whole is not warm? My local forecasts are showing, AGAIN, another arctic blast a week out. This is already turning into the coldest winter in my 23 years and I thought last year was bad! 34.7f this morning in Tampa Bay at my house 1 mile from the Gulf after yesterday's lower 50's high - the actual high occurred at noon 54f and dropped from there. I raise exotics in my backyard shadehouses/greenhouses and nothing is growing except in the greenhouse (barely). I am truly considering giving it all up if this keeps on. I teach during the day, so I need the weekend time to get things done and that is no longer happening. Too cold/wet/windy all the time. Oh well, another cold day and night ahead! Greg in Ne :angry: w Port Richey

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bubba

Jason, Thank you for the great Links. The Storm2K is outstanding and even has an active Florida page. It carries on to Hurricun coverage latter.

This is what I am looking for to broaden my amateur interest by seeing "real time" events unfold with experienced interpretation.There is staggering Arctic cold now in Minnesota (International Falls/-46F)and the question is how far South it moves.Those long term runs appear scary but seem to change. Sometimes for the good or bad. Many of the folks in Houston seem to be avidly hoping for a snow event.This is a little contrarian to those of us trying to hang on to tropicals! It looks like most of the cold steers to the North of Florida or atleast South Florida. Not sure places like DC, NY or even Atlanta will be coming out of Arctic cold for some time.

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happ

Here's what NOAA is forecasting for February. If it verifies, Texas should be warm. The rainfall forecast looks dismal for California. :( Part of the reason for the current frigid airmass over much of the nation east of the Rockies is a persistent high pressure ridge over the West Coast that is blocking all storms from entering California.

feb2011.gif

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jasons

Still keeping an eye on the cold air up in Canada. Models are not as cold with the front around the first of the month but there could be a snow or icing event for parts of Texas. We'll see, still a long ways away from now. I'm tired of wrapping my plants though!

Edited by jasons

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DCA_Palm_Fan

Jason, Thank you for the great Links. The Storm2K is outstanding and even has an active Florida page. It carries on to Hurricun coverage latter.

This is what I am looking for to broaden my amateur interest by seeing "real time" events unfold with experienced interpretation.There is staggering Arctic cold now in Minnesota (International Falls/-46F)and the question is how far South it moves.Those long term runs appear scary but seem to change. Sometimes for the good or bad. Many of the folks in Houston seem to be avidly hoping for a snow event.This is a little contrarian to those of us trying to hang on to tropicals! It looks like most of the cold steers to the North of Florida or atleast South Florida. Not sure places like DC, NY or even Atlanta will be coming out of Arctic cold for some time.

Hmmm

D.C. is having "Arctic" cold? Could have fooled me. I live here and the coldest we've officially been has been in the 14-19F range, (depending on where you are) and thats only been for a couple of rather brief (1 to 3 day) periods. We are coming to the end of one right now. The daytime highs have only been about 25 to 28F for a few days, and the nighttime lows have been anywhere from 5F to 20F. (again, depending on where you are) In the city that tends to the much warmer range (20F) and the far N/W suburbs is where you have occasionally found the single digits. On a whole, this winter has really only been slightly cooler than average. In spite of there being much less snow so far (we had 76" last winter) this winter, last winter was actually just a bit warmer. One of the noticable difference is there is a bit more ice on the Potomac River than last year, and it seems to stick around longer. That said, it does melt after several days to a few weeks. We did have a little last winter, but mostly over the past 10-15 years we dont get much ice, if any on the river.

Compared to how cold I have seen it get here from time to time, I would definitely not call our cold this winter "Arctic" in nature. Maybe a couple of night times for 2-6 hours or so sure, ok MAYBE kinda sorta arctic like, but not arctic. Minnesota, now THAT is some serious arctic cold. -46F... OUCH!!!!! :blink:

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jasons

These are the latest thoughts from a local met here in Houston (posts as wxman57) - note these thoughts are for Houston area:

If we step back and take a look at some of the signals that we're seeing, then it seems likely that there will be some type of significant event at the beginning of February. When I say that the pattern evolving appears similar to 1993, I don't mean that I expect another massive Gulf and east coast storm. It's possible that the pattern just leads to a major nor'easter.

What we do know is that there is some VERY cold air up in Canada now, and lots of it. With the pattern evolving, we have a very good shot at getting some quite cold Arctic air down here. Whether or not we get any frozen precip will depend on the details in the upcoming pattern - something we can't be sure of this far out.

The way I see it, there are 3 main possibilities for next week (around Feb 1-3):

1. Models are incorrect with the overall pattern and it's just more of the same (current weather). I'd say this isn't the highest probability, probably the lowest probability of the 3 options.

2. Significant dry surge of Canadian/Arctic air that may drop temps into the 20 degree range here or lower. Very hard freeze but no precip involved.

3. Moderately cold Canadian/Arctic air intrusion with secondary impulse moving through the cold air. This is what the GFS is forecasting and the Euro is hinting at around day 11-12.

I'm not ready to buy #3 just yet, but I could easily believe that we could get quite cold here in 9-10 days (#2 above). It's just so hard to get the timing and conditions here right for snow.

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_Keith

What happens to Houston, happens to me, so I am refusing to acknowledge any possibility other than number 1.

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Takil-Explorer

Well Florida looks like springweather/early summer!Well the north still cold nights but the south looks very nice!

Alexander

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jasons

There is still a lot of talk about an arctic outbreak of some kind for next week spilling down the plains. This is still a week +/- away so I don't expect much confidence on what type of airmass and 'how cold' until probably this weekend.

What this means for you: if you look at websites at the 7-14 day forecasts it is an exercise in futility. Even the NWS human forecasts are holding-off on mentioning anything for next week until there is more clarify on how the pattern will unfold. It's still wait and see, but still keep a close watch.

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jasons

Hi guys,

Nothing too major to add or to report today. In a way that is bad news for us because the models are consistent with bringing down a strong arctic/Canadian front down the plains early next week. The GFS still seems to miss the cold air and upper air pattern so the Euro is looking more and more like reality, and it's pretty darn cold for next week if it verifies.

I think those in Texas (at least for now) should start thinking about the possibility of the coldest air of the season dropping down next week...

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jasons

Here is the latest from a local met here in Houston. Looks like a Texas threat next week:

12Z Euro (and Canadian) are even colder than the 00Z runs. I still don't see much post-frontal moisture, though. And with the front driving well into the southern Gulf by Wednesday, the chances of a coastal low to throw moisture over the cold air are about zero. But the Euro and Canadian do indicate at least a weak disturbance (or two) moving south into Texas later in the week. If that's the case, then we could see passing snow flurries across Texas but no big snow event. And I do not currently see much of a freezing rain threat.

As for Houston, if the 12Z Euro or Canadian verify, then we could be looking at the coldest air of the season by a fair bit. Teens for Houston would be possible, though I wouldn't forecast such temps quite yet. Again, I do not buy the GFS solution at all. I think it holds too much energy back.

Farther east along the LA coast, the cold air could be a little colder than you've already seen, but not as dramatically colder as for the TX coast.

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jasons

It's been a depressing day folks....every subsequent model run latches onto the cold spilling down for next week. Euro is downright scary. I think teens for Houston (IAH) next week is now looking likely instead of just a possibility......

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_Keith

It's been a depressing day folks....every subsequent model run latches onto the cold spilling down for next week. Euro is downright scary. I think teens for Houston (IAH) next week is now looking likely instead of just a possibility......

Anything is possible, but I would not lose any sleep on this quite yet. Remember the last non-materializing model. I have read more than one article that basically said you could quote statistical norms and be just about as accurate as the 7 and 10 day out forecast.

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gsytch

I only use LTM to see patterns. I see Florida is to miss the brunt of the cold, with several forecasts showing a few days that are chilly not cold, then warming up. They are calling for near 70f here in Tampa Bay Sat, and mid 70's thru Wed. Logged an astounding 6.79" of rain in January with 2" from Tues....amazing in a LaNIna "dry" year. Last week's cold front saw 34.9f one morning, then it warmed up. That jet stream is suppose to deflect the cold from FL. We deserve a break!

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jasons

Latest update from a local met here in Houston:

Ok, folks, I wanted to take a look at the 12Z runs today to see how they agreed with or differed from last night's run (Euro and GFS in particular). Here's what I see. The GFS appears to be making a well-known error in hanging up the Arctic air along the Red River on Monday night, waiting for the upper-level disturbance to pass before driving the cold air south. The Euro and Canadian don't appear to be making this "mistake". They both drive the Arctic air straight south to the Texas coast by sunrise Tuesday.

There's cold air in place across Texas on Tuesday and it appears that there will be a disturbance moving across the state on Tuesday. The Canadian is weakest with the disturbance, indicating little post-frontal precip. GFS is strongest (and slowest) of the 3 main models, holding energy back well to the west. But this is a common error with the GFS. The Euro, while aligned with the GFS on the 00Z run is now about 8 hours or so faster than the GFS with the passing upper-level feature. This does look more reasonable than the much slower GFS.

What does this mean for Texas? I think that Arctic air will be in place across the state with widespread precipitation on Tuesday. For us, it looks like most of that precip will be cold rain (temps in the 40s). But up north, say from the Hill Country through Waco to Dallas and eastward, temps may be sub-freezing. This could set the stage for a period of freezing rain changing to sleet and finally snow on Tuesday as the precip ends. Too early to estimate any amounts or precise locations of winter precip. I suppose we can't rule out the possibility that the Houston area could see some sleet and maybe (just MAYBE) a slight chance of a few snow flurries as the precip ends Tuesday afternoon/evening. By no means would I forecast such a thing at this time, though.

Now what happens after Tuesday? All 3 models drive the high center straight south to west-central Texas on Wed-Thu. Canadian and Euro are MUCH colder than the GFS. For example, the GFS predicts 850mb (5000ft) temps over Houston around +3F Thursday morning. The Canadian forecasts -8C and the Euro about -11C. That's a tremendous difference. I think the GFS is probably a good bit too "warm" with that forecast but I really can't tell just how cold it might get until the cold air is actually on the move south down the Plains on Sunday.

With it's very cold 850mb temps, the Euro is forecasting 2 meter temps of 20F for Houston on Thursday morning. This is about 5 degrees colder than it forecast with the last front, when IAH reached 26 degrees. GFS only forecasts upper 20s. I think lAH may record a low on Thursday of between 19 and 24 degrees based on a combo of the Euro/CMC projected temps. Not a 1989 or 1983 event by far, but the coldest air of the season.

Up "north", it's interesting to note that the Euro 2m temps around Abilene are 0F to a bit below zero for Thursday morning. So you folks in Dallas/Ft. Worth could see some quite cold air (10-15 degrees). Just a possibility for now, not my forecast.

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jasons

There is finally some more clarity around next week's event, it seems.

Florida gets lucky this time, but Texas...notsomuch.

A powerful arctic front will barrel down the plains and easily deliver the coldest nights of the season over Texas on Thursday and Friday mornings. A hard freeze looks likely for the entire state except maybe the RGV. The finer details will have to be worked out over the next few days, but for now, plan for a hard freeze in most of Texas next week. Keep a close watch on the weather as the 'official' forecasts for next week are going to get colder.

Edited by jasons

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jasons

Here it comes - this is from Houston local met Jeff Lindner with the Harris County FLood Control District:

Next week:

Models have finally come into better agreement on the cold air outbreak next week. GFS has trended significantly colder matching closer to the very cold ECMWF and CMC. Massive 1050mb arctic high will move from NW Canada to just north of the Montana border and then plunge down the plains toward TX. This is looking like a strong direct shot of very cold air straight into TX. Strong arctic boundary will roar down the plains and cross off the TX coast by noon Tuesday. 120kt jet streak and strong frontal lift will support a round of thunderstorms Monday night and Tuesday and some could be severe. Temperatures will fall at least 30 degrees with the frontal passage as very strong cold air advection with the arctic high building over the region. Will see highs all areas in the 60's prior to the front with temperatures rapidly falling into the 30's behind the boundary with NW winds of 20-30mph producing wind chills at or below freezing by Tuesday evening. Freezing line will march southward rapidly during the day on Tuesday reaching our northern counties by mid afternoon and likely I-10 by mid evening.

Still some debate on if clouds will linger behind the front as the CMC shows some overrunning, while the ECMWF and GFS show a drier mid level air mas. Fingers crossed that the CMC is correct and we have a saving cloud blanket, if not very cold overnight lows into the teens are likely for areas along and N of US 59 potentially for at least 2 nights with highs Wed-Thu only in the mid to upper 30's. Raw GFS guidance is showing 19 for IAH on Friday morning which would be 1 degree colder than the outbreak last January. Still plenty of time to fine tune the details of this incoming air mass and just how cold it may get, but there is growing confidence that hard freezes possibly killing freezes will be possible mid to late next week. With the center of the arctic high remaining NW of the region Tue-Thu, NW/N winds of 10-20mph will continue and this will drive wind chills into the teens and 20's for parts of the region and possibly sub-zero as far south as I-20.

Residents should take the warm weather of the next 2 days to prepare vegetation and livestock for the impending cold blast. Additionally pipes and sprinkler systems should be protected given the potential for an extended period of sub-freezing temperatures. Advection freezes as the one likely incoming Tuesday night and Wednesday night are particulary damaging to vegetation as the "greenhouse" effect is harder to produce on windy nights.

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Erik

Jason,

here it comes indeed. It just arrived here in Oklahoma.

Yesterday, Tulsa tied a record high. We napped in the sun by our uncovered palms ( 20 in ground). Morning low of 40 oF, but now the winds are out of the north and the temp. is dropping. I'll spend the day packing up the palms again, with the season lows coming in a few days. So, heads up, Texas--use today to get your palms ready. --Erik

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Xenon

Lows in the 20s all week next week with an ultimate low around 20F :( Even Ciudad Victoria/Soto la Marina, Mexico are expecting a light freeze, and they're south of the Tropic of Cancer....

:( Jonathan

Edited by Xenon

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Erik

Lows in the 20s all week next week with an ultimate low around 20F :( Even Ciudad Victoria/Soto la Marina, Mexico are expecting a light freeze, and they're south of the Tropic of Cancer....

:( Jonathan

:(

I'm looking at highs in the 20s (oF) all week, with lows approaching 0 oF.

I just finished making sure my electric protection is working. Water bottles all around. Now on to applying a deep mulch of hay while it is still above freezing. :angry:

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war_eagle

It's going to be an ugly week for sure. Here's the NWS forecast me:

Tue: 68/27 - rain early, clearing with front passage

Wed: 38/26 - partly sunny day, mostly cloudy night

Thu: 42/26 - mostly cloudy

Fri: 44/29 - mostly cloudy

Sat: 52/? - mostly sunny

If these temps hold it won't be quite as bad as the stretch in early Jan 2010. We had frozen precipitation and three nights below 25 (lowest at 19.8) at my house.

On a sad note, it will almost assuredly be the end for my 2 foxtails. They are about 15' tall overall and have outgrown my ability to cover them. Plus, I've permanently given up covering any plants/trees. Something hardier will go in their place in the spring. While it's sad to see them go, it sure is nice to not be running around like a chicken with its head cut off running extension cords, xmas lights, sheets, tarps, etc, etc.

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_Keith

Wea are still showing 4 nights with each around 32 degrees. That would be plenty cold enough. Hope it doesn't slip lower.

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Erik

it sure is nice to not be running around like a chicken with its head cut off running extension cords, xmas lights, sheets, tarps, etc, etc.

I have about 70 chickens so I know what you mean.

I have been doing just that on what should be my day of rest.

Note to self: move to Texas....

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jasons

Yes, it looks like some very cold air is now a certainty. There is still some question as to how cold because the models (Euro esp.) want to show clouds and maybe even a chance of snow in the Friday timeframe. Even if we don't clear-out and see teens for lows, we do have the potential for it be be in hard-freeze territory for many, many hours. And it'll be windy too. joy. Here's the latest NWS 4-cast for me, it sorta splits the difference between the two scenarios.

Tuesday: Showers and thunderstorms likely, mainly before noon. Cloudy, with a temperature rising to near 66 by 8am, then falling to around 42 during the remainder of the day. Windy, with a south wind 15 to 25 mph becoming northwest. Winds could gust as high as 30 mph. Chance of precipitation is 60%.

Tuesday Night: Mostly cloudy, with a low around 25. Blustery, with a north wind between 15 and 20 mph, with gusts as high as 25 mph.

Wednesday: Partly sunny, with a high near 37.

Wednesday Night: Mostly cloudy, with a low around 23.

Thursday: Mostly cloudy, with a high near 40.

Thursday Night: Mostly cloudy, with a low around 23.

Friday: Mostly cloudy, with a high near 44.

Friday Night: Mostly cloudy, with a low around 26.

Saturday: Mostly sunny, with a high near 52.

Edited by jasons

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Erik

Man, I'd take that!

I have ice tomorrow night and snow Tuesday, then lows to about -18 oC by Thursday morning.

That is tough even for a needle palm! Wish me luck. --Erik

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mjff

I don't know about Houston, but now they are saying my area will have lows Wednesday and Thursday of 10F with highs in the mid-20's. That's after several inches of snow tonight. I thought we were going to get a break after last winter, which was the type of extended cold we only get about once a decade, now two years in a row. This stinks. I'm guessing the stuff that survived last winter will survive this too, since it will be similar both in duration and low temperature, but I was really hoping some of these trees wouldn't be defoliated two years in a row. Do any of the models show anything better for the San Angelo area? So far they have been off by 5 degrees on our lows every time they have said we would get below 20F. I hope their streak continues. I think their models are failing to account for how warm the soil still is out here with the much warmer than normal temperatures we have been having, but that may not make much difference this time with the strong winds they are saying we are going to have.

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jasons

That is some very cold air charging down the plains! The saving grace may be the fact we'll have clouds and a chance of winter weather across Texas, but it's still going to be brutal. Bye Bye Majesty Palms.

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Erik

We just dropped below freezing here and won't be back above until Saturday, with lows to - 18 oC a couple of times.

Edited by Erik

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war_eagle

Yep, say bye bye to a lot of plants. Here's the latest from NWS for me:

Tu: 66/23 - already down to 43 at 7am

We: 37/23 - partly cloudy, wind chills 4-14

Th: 37/26 - cloudy, 60% snow overnight, light accumulation

Fr: 38/27 - cloudy, 60% snow AM, 30% snow PM, light accumulation

Sa-Mo: highs in mid 60s, lows low 40s

The snow and ice will be absolutely brutal on the plants. I think many could handle the temps if it were to be dry, but those temps with ice on everything will be a disaster. Get ready for some blow torch pictures.

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jasons

The snow and ice could be bad but in this case it will help. Otherwise, if we were to clear-out, we'd easily see teens.

Here is from a local met, Jeff Lindner:

Memorable arctic outbreak arriving across the region this morning.

Hard Freeze Warning issued for all areas for tonight

Wind Advisory issued for all areas through late this evening

Winter Storm becoming likely Thursday night/Friday with accumulations of snow

Discussion:

Much talked about arctic outbreak is here with a powerful front cutting SE TX in half this morning with temperatures falling into the 30’s from the upper 60’s within a few minutes of the fronts arrival. Blizzard conditions ongoing over W TX into N TX and OK with howling NW winds (temperatures in the teens and 20’s, wind chills in the -10 to 0 range). In fact roughly 100 million residents across the plains and Midwest will see more than 1 foot of snow and blizzard conditions today.

Arctic boundary is way ahead of model timing and will be off the coast by 800-900am. Very strong NW winds of 30-40mph will develop behind the initial damaging winds along the leading edge of the squall line.

Will break out impacts for wind and temperatures and then break out forecast time periods below.

Wind Advisory:

Massive arctic surface high building down the plains will result in a powerful pressure gradient with very strong winds howling well into tonight. These winds will drive wind chills into the 1’s and 10’s this afternoon and evening (a rare experience for those this far south). Sustained NW winds of 25-35mph with frequent gusts of 45mph will be likely today and into tonight. Winds should finally begin to relax into the 15-20mph range early Wednesday.

Hard Freeze Warning:

Hard Freeze warning is in effect for the entire area (all counties) for tonight into Wednesday. Forecasting lows in the mid to upper 10’s over our northern counties to lower 20’s central to upper 20’s at the beaches and on the island. Areas north of HWY 105 will be below freezing for up to 20 hours, north of US 59 16 hours and along the coast 6-8 hours. Will see similar cold lows again on Thursday and Friday mornings.

Winter Storm Threat (Thursday/Friday):

Confidence is growing that a winter storm will affect the region Thursday night and Friday. Impressive upper level trough over the northern Rockies will drop southward into the base of the long wave trough over the SW US allowing the piece of energy to deepen into an upper level low. Cold arctic dome will be firmly entrenched over the region with forecast soundings showing freezing/subfreezing profiles for the entire area. ECMWF and CMC continue to be slower with the ejection of this trough and will side with the stronger and slower solution (GFS and NAM are fastest)> The GFS was too fast on the Sunday system and SW US upper troughs tend to eject slower than models project. The slower motion of the trough will allow a greater period of moisture to pool and advect into the 850-700mb region ahead of the trough. Feel the models (especially the GFS) is too dry in the 500-700mb layer (ice growth layer) and that more moisture than being shown will be available. Large scale deep layer lift will begin Thursday afternoon with increasing clouds and lowering cloud bases. Should start to see sleet/snow develop along the Rio Grande River and near Corpus Christi by early evening and then spread/develop N/E overnight. Combination of isentropic lift in the deep cold dome and potential for low to mid level frotogenic forcing points toward the formation of multiple meso scale snow bands (similar to Dec 2004). Surface dewpoints will be in the 10’s and low level dry layer will wet bulb as the precipitation starts keeping surface temperatures below freezing for the entire event. Far south, NW Gulf surface low will develop and has the potential to bring a slight 850mb warm nose back toward the coastal locations early Friday morning which may result in P-type changing to or mixing with IP (sleet). Dominant P-type will be snow for all other locations away from the beaches.

Accumulations:

Looks like we indeed will see accumulations with this event. CMC is by far the wettest model and the GFS the driest with the ECMWF in the middle. Will go wetter than the GFS but not as bad as the CMC just yet. Dec 04 snowstorm looked the same way on the models (moisture starved up until the event started and then bam). Looks like accumulations will be possible across the entire region with the best chances in a band from W of Corpus Christi to Victoria to Wharton. Still too early to talk totals, but a rough early estimate with a 10:1 ratio (usually we are closer to 7:1 down here, but with such cold temperatures the normal ratio may work out better) would be about 1-3 inches south of I-10 on the ground. If the CMC is correct we would be talking 6-8 inches across much of the area…a blizzard by our standards!

12-Hour Forecasts (Today through Friday):

North: along and north of a line from Brenham to Conroe to Livingston

Central: along and north of a line Victoria to Sugar Land to Humble to Liberty

South: inland coastal counties to US 59

Coastal: beaches

Today:

Showers and thunderstorms before noon following by rapidly falling temperatures. NW winds 30-35mph with gust of 45mph. Wind chills in the 10’s and 20’s early falling into the 1’s and 10’s by sunset. Temperatures falling into the 30’s all areas by mid afternoon and upper 20’s north.

Tonight:

Hard Freeze Warning in effect. Cloudy and windy with NW winds 20-25mph and gusty. Wind chills in the 1’s and 10’s.

Lows:

North: 16-19

Central: 20-24

South: 25-28

Coastal: 28-30

Wednesday:

Mostly cloudy and very cold with NW winds of 15-20mph.

Highs:

North: 30-34

Central: 33-37

South: 35-38

Coastal: 36-39

Wednesday night:

Mostly cloudy and very cold with NW winds of 10-15mph

Lows:

North: 17-20

Central: 22-25

South: 26-28

Coastal: 28-30

Thursday:

Increasing clouds and continued very cold. N winds 10-15mph

Highs:

North: 32-35

Central: 34-37

South: 35-38

Coastal: 36-40

Thursday night:

Cloudy with snow developing. Chance of snow 50%. Snow may mix with sleet near the coast and south of Victoria. Accumulations possible.

Lows:

North: 22-25

Central: 23-26

South: 25-28

Coastal: 29-31

Friday:

Cloudy with a 60% chance of snow, some snow may be heavy at times. Snow may mix with sleet early along the coast. Accumulations likely.

Highs:

North: 30-34

Central: 29-34

South: 30-33

Coastal: 31-34

Actions:

Preparations for an extended period of freezing weather should be completed at this time.

Hazardous driving conditions may develop Thursday night and early Friday as winter precipitation develops over the area.

TXDOT started applying anti-ice agent to freeways and flyovers in Montgomery County yesterday and these actions will be increased and expanded to other areas on Wednesday. Very cold ground temperatures will make this agent only somewhat effective. Believe the first amounts of snow early Friday will melt with the remaining little ground warmth and then freeze as a layer of ice on most surfaces and then snow will accumulate on top of this layer of ice making for very dangerous travel conditions. Unlike past events surface roads (not just bridges and overpasses) will likely be impacted given the cold ground when the event starts.

Active TXDOT Road Condition Map:

http://www.txdot.gov/gis/hcrs_main/viewer.htm

Aviation:

Significant travel impacts as US central plains blizzard impacts major airports across the Midwest, plains, and into the NE. Suspect some airports will close completely as snow removal operations will not be able to keep up with heavy snow/blowing snow. End of the week will bring our own problems locally with winter precipitation. Suspect de-icing of aircraft control surfaces will be required at all local airports by Thursday night which will result in long delays.

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war_eagle

I guess all the storm2k folks got what they wanted. Us plant folks are screwed though.

I grew up here in Houston and remember getting out of school once in the 90s just *see* a few snow flurries. of course, as soon as I take an interest in palms/tropicals it starts snowing here every year. If it snows this week, which looks inevitable at this point, it will be the 4th consecutive year with snow accumulation at my house. Unbelievable.

Geez, at this point I just hope the Butias, Sabals, Trachys, and Chamaerops will be okay. The younger Washys will be defoliated yet again, but they always come roaring back. My P. sylvestris was about 30-50% burned last year, but they put on fronds so fast you couldn't tell anything had happened by June. I guess this is just the new norm. Ugh.

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