Texas Winter 2013-2014

[Portastorm]

Speaking of -EPO, I was flying my plane up to Chicago the third Sunday in July, and at 6000 feet MSL it was -4C and commercial pilots were complaining about icing going through the cumulus clouds on approach to Springfield IL. That was the day after Chicago set a record low July high temp of 65F. It was April flying in late July.

I love the aviation perspective here. Thanks opticsguy for posting. That's an interesting story and a component of the weather rarely discussed in our forum here. Please feel free to chime in more often.

FWIW, I enjoy listening to the KAUS airport tower from the aviation website (LiveATC.net) when the weather is challenging to hear how the pilots cope with it and strategies they use.

[Portastorm]

Worrisome to see a 1040mb Arctic high centered over the Hill Country at 00Z Monday night via the 00Z NAM/4km WRF. That would suggest winds going calm with ideal radiational cooling conditions with clear skies. Tuesday morning looks very cold across our Region.

If I'm not mistaken srainhoutx, the 0z NAM (45 hrs) compared to its 12z run earlier (57 hrs) shows the high a wee bit stronger and placed over the central part of the state as compared to the northeast part of the state. That could mean some low temps a bit lower even if verified, eh?!

[SaskatchewanScreamer]

Worrisome to see a 1040mb Arctic high centered over the Hill Country at 00Z Monday night via the 00Z NAM/4km WRF. That would suggest winds going calm with ideal radiational cooling conditions with clear skies. Tuesday morning looks very cold across our Region.

If I'm not mistaken srainhoutx, the 0z NAM (45 hrs) compared to its 12z run earlier (57 hrs) shows the high a wee bit stronger and placed over the central part of the state as compared to the northeast part of the state. That could mean some low temps a bit lower even if verified, eh?!

I am so so so glad I have Sunday off!!!

[srainhoutx]

That it does, Portastorm. I now see HGX has issued a Hard Freeze Watch for all of SE Texas N of I-10 including Harris County.Teens are looking more likely now and daily records may fall for CLL and IAH.

[Jarodm12]

take a look at the rap much further south with precip from 10 hours onward.
http://www.instantweathermaps.com/RAP-p ... E&hour=013

even the 00utc gfs east dallas and points eastward


http://www.instantweathermaps.com/GFS-p ... E&hour=012

and now this
http://www.instantweathermaps.com/RAP-p ... E&hour=010


notice the south east movement of the tail end of the precip using highways you can see its trajectory
http://radar.weather.gov/Conus/southplains_loop.php

pretty decent inflow of moisture rh 70% and higher dew points in the 40s dfw area
http://www.goes.noaa.gov/ECIR3.html

latest rap, i dont know guys you tell me are the models not trending more southward?

http://www.instantweathermaps.com/RAP-p ... C&hour=008

why is there zero conversation about this every new high res model is point towards snow and sleet in north texas tonight?

[gboudx]

DFW NWS does show light wintry precip for the eastern part of the CWA. Just east of me here in Rockwall.

[Jarodm12]

:uarrow: DFW NWS does show light wintry precip for the eastern part of the CWA. Just east of me here in Rockwall.

well im thinking based on the latest model data we are going to see some snow looks to be almost all of dfw like i said i could be wrong and i am not a professional. But the rap continues every run to trend more southward now with measurable precipitation. That said my confidence in at least some light snow or sleet showers is growing.

[gboudx]

What's the timeframe? Looks like early tomorrow morning.

[Jarodm12]

looks to be between 4am and and 9am.
wonder if nws is going to say something about this in a update.

waiting for the next rap run

[Rgv20]

0zECMWF continues to hint of possible very very light frozen precipitation late Monday Night early Tuesday morning for the western part of the Rio Grande Valley.

[Ntxw]

While of course we have a very cold air mass still settling in the US and possible temps might bust to forecasts, latest model trends have muted the thaw for the plains. Wxman57 will get his mild, moderation but likely with clouds and possibly rain for a couple of days. The coasts will warm up, meanwhile nearly all guidance and ensembles are now showing rebuilding of very cold air in Northern and NW Canada with building ridges both in the Pacific, Asia, and Arctic in the medium range. That means mid month has another cold plunge possibility in the making. Our friend Srain has been passing hints and he may very well be right.

[SaskatchewanScreamer]

This is the voice of *The Canadian Winter*

[youtube]http://www.youtube.com/watch?v=_BaKgJcv9MA#t=00m44s[/youtube]

Take heed Texas (and the United States)!

[Ntxw]

Bring it We can take it!

And if we're not going to get snow, at least the Euro tonight shows widespread 2-3 inches of rain for the state next weekend with slow moving cut off low. It seems the past few years we've seen this drenching rain set up in early Jan of late, perhaps this liquid gold will follow suit.

[ravyrn]

looks to be between 4am and and 9am.
wonder if nws is going to say something about this in a update.

waiting for the next rap run

Hey Jarod, thanks for keeping us updated on the shortrange high res models. I hope your thoughts pan out! Also, you may want to consider throwing the forum disclaimer in your sig just to stay on the safe side of the forum rules. Keep the updates coming sir, and I hope you guys up northwest of me get some of that white fluffy stuff!

EDIT: Also, put your location on your profile so we know where you're at! I believe you can do so from the "user control panel" link at the top right of the window.

[ravyrn]

:uarrow: Bring it We can take it!

And if we're not going to get snow, at least the Euro tonight shows widespread 2-3 inches of rain for the state next weekend with slow moving cut off low. It seems the past few years we've seen this drenching rain set up in early Jan of late, perhaps this liquid gold will follow suit.

Use your weather voodoo to either make it the white stuff or if it has to be rain, to put it above highland lake's watershed cause those suckers need some loving!

[opticsguy]

Porta,

About that July trip to Chicago. I checked the NAM soundings that morning and parcels could convect all the way to 20,000 feet over IL. Needless to say it was BUMPY, and my little plane was getting caught in 800 fpm updrafts. A skilled glider pilot could have stayed up all day. I just wanted to get on the ground.

Contrast that to a year earlier on the same trip and my engine was overheating because it was 33C at 5500 feet over Eastern OK.

Not TX weather, but a cool animation anyway. Watch Lake Michigan freeze over in the next 120 hours
http://www.glerl.noaa.gov/res/glcfs/anim.php?lake=m&param=icecon&type=f

[srainhoutx]

The Arctic boundary has passed Caldwell where temps have dropped to 43F and gusty NW winds to 30 MPH are underway. This initial shot of colder air will be near the Coast by noon and temperatures will drop quickly into the 40's. The overnight guidance has trended colder once again and lows tonight will quickly fall into the low 30's with mid to upper 20's expected by mid night into Metro Houston. The Hard Freeze Watches will likely be changed to a Hard Freeze Warnings later today and expanded a bit further S as temperatures in the low to mid teens are now expected N of I-10 early Tuesday as the Arctic High settles across Central Texas late Monday. HGX is still expecting near 10-12 hours below freezing tonight and 12-15 hours below freezing Monday night into Tuesday morning. Freezing temperatures are expect all the way to the Coast where Galveston may flirt with a record breaking upper 20's and IAH may see the first temperature readings in the teens since January 1996 when a low of 19 was recorded on January 9th, 1996.

[srainhoutx]

Morning Update from Jeff:

Significant arctic outbreak arriving into the region currently.

Damaging hard freezes nearly certain both Monday and Tuesday mornings….Hard Freeze Watch is in effect for much of the area for tonight.

Preparations for extended periods of sub-freezing temperatures must be completed today.

Arctic frontal boundary is plowing into SE TX this morning with College Station 43 (NW wind gusting to 30mph) and Houston 63. Boundary will move southward and off the coast this morning bringing temperatures quickly into the 40’s areawide under strong cold air advection. North winds will increase into the 20-30mph range post front with gust to over 40mph possible.

Tonight-Monday AM:

Skies will clear by mid to late afternoon,, but large arctic high will still be moving down the plains resulting in continued strong cold air advection and winds overnight. Would normally not fall too much below freezing with so much wind continuing, but this air mass is very cold and an advective freeze will usher into the area starting this evening and lasting into Monday morning. Freezing conditions are likely for 8-12 hours.

Lows Monday AM:

N of I-10: 23-27
Metro Houston (inside Beltway 8): 25-28
N of US 59: 25-27
Coastal: 29-33

Winds will continue in the 5-15mph range overnight driving wind chills into the teens across the entire area.

Monday:

Arctic high pressure settles over the region with winds gradually weakening, but very little warming. Areas north of I-10 may not even reach 40 with areas south of I-10 reaching the lower to mid 40’s.

Monday night- Tuesday AM:

Very cold conditions are expected with potential for near record low establishment.

Arctic high will be near or just NNE of the region allowing very weak wind, but still a weak (2-5mph) NNE wind allowing cold air drainage into the region form the NE. Skies should be mostly clear and dewpoints ranging from near 0-10 across the region supporting good cooling conditions. Temperatures will fall to freezing at sunset and remain below freezing into Tuesday morning. There is some hope that warm air advection may begin just prior to sunrise on Tuesday as the arctic high moves eastward and stop the temperature drop, but after reviewing the latest guidance this does not look to happen until after 600-900am time period which is after the period of maximum cooling. Will also have to watch for some mid level clouds to enter the picture, but there is more going for a very hard freeze at the moment than against. Freezing conditions are likely for 12-16 hours.

Lows Tuesday AM:

N of I-10: 16-20
Conroe area: 14-17
Metro Houston (inside Beltway 8): 22-26
N of US 59: 19-23
Interior coastal counties: 26-28
Beaches: 29-31

Freeze preparations:

Duration and intensity of the incoming freezes requires preparation of tropical vegetation, pipes, and pets/livestock.

Shut off and drain sprinkler back flow devices (many of these devices were damaged in the freeze of similar magnitude in 2011).

Disconnect water hoses and cover hose bibs

Cover any exposed outside water pipes

Open exterior facing cabinets to allow warmth against exterior house pipes (could be some issues with house pipes freezing especially N of HWY 105)

Cover and protect tropical vegetation including sensitive citrus

Provide shelter for pets/livestock. Note typical water sources for pets and livestock may ice/freeze over.

[Ntxw]

Definitely not your everyday cold wave even if Texas doesn't take the brunt of it. At a glancing blow it's still one of our coldest air masses the decade. NA is an icebox, Ms Screamer is probably trying to stay warm in her igloo. Big high is coming down, lets see how big it gets.

The last time we saw such an air mass to cover the continent was probably 1996

[Rgv20]

NWS Brownsville early morning discussion....Not everyday you read this kind of discussion out of Brownsville! The official forecast out of the NWS for my area.....Monday Night: A 20 percent chance of snow after midnight. Partly cloudy, with a low around 32. East northeast wind 3 to 7 mph.

LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
OUR DYNAMIC AND COMPLEX WEATHER PATTERN FINDS MONDAY NIGHT NO
EXCEPTION. AT THE SURFACE HIGH PRESSURE WILL HAVE ESTABLISHED AN
AXIS ACROSS OUR NORTHERN COUNTIES WITH ECM/GFS/NAM AGREEING ON ABOUT
1036-1038MB AND SURFACE DEW POINTS IN THE TEENS ACROSS THE NORTHERN
RANCH LANDS...BUT LOW TO MID 30S IN THE MIDDLE AND LOWER VALLEY WHERE
NORTHEASTERLY WINDS OFF THE GULF OF MEXICO WILL PERSIST INTO THE
EARLY EVENING. SYNOPTIC PATTERN SUGGESTS THE BOUNDARY LAYER WILL
DECOUPLE EARLY IN THE EVENING AND ALLOW THE WINDS TO GO CALM IN THE
NORTH EARLY IN THE NIGHT. AT THE SAME TIME A WEAK EMBEDDED SHORTWAVE
TROUGH MOVES OVERHEAD AND A BROAD JET MAXIMUM EMERGES OFF THE LEE OF
THE SIERRA MADRE/ROCKY MOUNTAINS. THIS KEEPS THE 500-700MB LAYER
RELATIVELY SATURATED AND INCLUDES MODEST ISENTROPIC LIFT AROUND 305K
WHICH IS AT 650 TO 700MB IN THIS TIME FRAME. THE ECMWF IS MOST
AGGRESSIVE WITH THIS BUT IT IS SLOWER WITH THE 500MB SHORTWAVE
TROUGH AND ADDS SOME MID LEVEL LIFT/DCVA TO THE EQUATION. IT DOES
MAKE SENSE THAT THE SHORTWAVE WOULD MOVE A LITTLE SLOWER AS IT WAITS
ON A PUSH FROM THE EMERGING ROCKIES JET MAXIMUM AND THE GFS/NAM MAY
BE TOO QUICK. THIS HAS BEEN THE CASE WITH A COUPLE OF THESE WEAK
SEMI-CUT OFF TROUGHS SO FAR THIS SEASON.

THIS CREATES A BIT OF A QUANDARY FOR THE FORECAST. RADIATIONAL
COOLING CONDITIONS WILL LIKELY BE PRETTY POOR BY 3 TO 4 AM OVER THE
ENTIRE AREA BUT MAY BE PRETTY GOOD IN THE EARLY EVENING BEFORE CLOUD
COVER DEVELOPS AND/OR IS SLOWER TO DEVELOP THAN FORECAST.
MET/MAV/ECM MOS IS CALLING FOR LOWS AROUND 25 TO 26 AT HBV/BKS AND
32/33 AT HRL/MFE. HOWEVER THE LIGHT NORTH WIND IS PROBABLY
OVERSTATING THE EFFECTS OF OVERNIGHT COLD AIR ADVECTION...AND WINDS
WILL PROBABLY BE LESS THAN WHAT THE MOS INDICATES DURING THE
OVERNIGHT. AT THE SAME TIME THE NORTH POLE ORIGINATING AIR MASS IS
PROBABLY A LITTLE COLDER THAN THE CLIMO SET USED BY THE MOS NORMALLY
SEES...AND SURFACE OBSERVATIONS FROM THE PLAINS SEEM TO SUPPORT
THAT. AT THE SAME TIME PRECIPITATION DEVELOPING IN RESPONSE TO THE
MID LEVEL ASCENT AND ISENTROPIC LIFT WILL...NORTH OF THE VALLEY...BE
FALLING THROUGH A VERY DRY LOWER ATMOSPHERE AND EXPECT THAT WET BULB
COOLING WILL PLAY A ROLE IN LOWERING TEMPS AT LEAST A FEW DEGREES.

SO WITH ALL THAT SAID CONTINUED TO FORECAST FREEZING TEMPERATURES
OVERNIGHT ROUGHLY NORTH AND WEST OF A LINE FROM RIO GRANDE CITY...TO
LASARA...TO HIGHWAY 77 IN KENEDY COUNTY AND HAVE ISSUED A FREEZE
WATCH FOR KENEDY/BROOKS/JIM HOGG/ZAPATA COUNTIES. NORTHERN HIDALGO
AND STARR COUNTIES MAY SEE SOME SUB FREEZING MINS BUT THE NUMBER OF
HOURS NEEDED FOR FREEZE WARNING WERE NOT MET IN THE NEW FORECAST.
ALSO BELIEVE THAT INCREASING DEW POINTS/MOISTURE OVER THE SOUTHERN
HALF OF THE CWA WILL FURTHER PROTECT THE VALLEY FROM SUB FREEZING
TEMPS AND ACTUALLY NUDGED UP OVERNIGHT MINS IN PLACES WITH 35 AT MFE
36 HRL 39 BRO FOR EXAMPLE. REGARDING PRECIPITATION NAM/GFS/ECMWF
FORECAST SOUNDINGS SHOW A SLIGHTLY COOLER THAN ISOTHERMAL LAYER
BELOW 700MB BELOW AN INCREASINGLY SATURATED DENDRITIC SNOW GROWTH
REGION. THERE IS A WARMER LAYER NEAR THE SURFACE BUT THAT IS HOUSED
IN A VERY DRY REGION ACROSS OUR NORTHERN ZONES. MOST LIKELY ANY
PRECIP THAT DEVELOPS WILL EVAPORATE IN THAT LAYER BUT IF IT DOES
REACH THE GROUND IT WOULD MOSTLY FALL AS SNOW...WITH WET BULB
COOLING WIPING OUT THE SMALL AREA OF 1 TO 2 C TEMPS AT AROUND 850MB
IN ORDER FOR THE AIR MASS TO SATURATE ENOUGH TO PRODUCE PRECIP. IN
THE VALLEY HIGHER LOW LEVEL MOISTURE SHOULD PREVENT ANY TYPE OF
FROZEN PRECIP...AND THE PRECIP CHANCE IS ONLY 20 PERCENT FOR NOW.