Texas Fall-2014

[HockeyTx82]

Not sure where to post this.

U.S. weather system hacked, affecting satellites

http://money.cnn.com/2014/11/12/technol ... ?hpt=hp_t2

Admins, please move if needed.

[Ntxw]

Not to derail but this so far has been one heck of an arctic blast for the mid section of the country. Laramie, WY had a high of 60 just three days ago, their high today was -1 low of -23. Not too shabby in our neck of the woods either Childress had a high of 87 a few days ago and today it was 28.

[aggiecutter]

10:30 radar image:

[ravyrn]

NWS FWD doesn't seem to be buying the models that are showing snow because of a lack of moisture, it's probably going to take the Euro and both GFS to show more moisture before they put any chances of precip in the forecast.

Another masterpiece by Cavanaugh, FWIW.

Dennis gets picked on by other FWD mets for being so verbose, but most of the S2K community will read his work as the gospel.

I messaged him on facebook last October telling him how awesome he is and sharing with him many sentiments expressed in our thread (such as calling him the Tolkien of AFDs). This was his response:

"Thank you sir, I really appreciate that I just randomly clicked on this "other" tab to see what it was and why there was a little number "2" next to it. I had no idea these were actually messages, I always figured it was some sort of game notification or something. At any rate, sorry I didn't respond to you in a more timely manner, apparently I fail at Facebook . Thanks again, take care!"

So he appreciates our appreciation for his awesomeness!

[Ralph's Weather]

Hoping some makes it into E Tx. The models, besides the sort term ones, missing this fuels hope that we will get some real winter precip Sunday though the models are dropping it right now.

[ronyan]

The 0z GFS continues to trend colder with 2m temps tomorrow night and Mon & Tues next week for SE TX. Widespread freeze along the gulf coast @ 156 hrs.

[weatherdude1108]

Not to derail but this so far has been one heck of an arctic blast for the mid section of the country. Laramie, WY had a high of 60 just three days ago, their high today was -1 low of -23. Not too shabby in our neck of the woods either Childress had a high of 87 a few days ago and today it was 28.

That is incredible! Stepping outside, the air mass just feels different with the constant breezes and cold air advection. Not often that I think the Sun feels nice down here, until we get an Arctic/Yukon air mass invasion.

[WeatherNewbie]

Definitely some sleet in Frisco tonight. Heard/saw it while visiting a friend.

[Brent]

3-4 minute sleet shower in Allen, it was enough to make the wipers sound slushy on the car lol

[ludosc]

Ryan Maue @RyanMaue
So much for that strongly negative AO. All the models gonna bust

[srainhoutx]

37F and a very cold rain in NW Harris County at this time.

[HouTXmetro]

yeah it's 39 here in Humble and raining.

[TeamPlayersBlue]

37 and really hard rain here in Fort Bend County too. NWS wasnt too keen on this happening. Temp dropped hard with the rain. Not expecting anything but rain. 850 line too far north

[TeamPlayersBlue]

https://www.facebook.com/KHOUBrooksGarner

Just came across this. Had no idea. My wundermap is jumping back and forth with sleet and rain on the radar now

[somethingfunny]

We had some "illegal" sleet pellets fall across North Texas a few hours ago! I took a photo of them in my yard (look very closely) .... maybe we should cancel school just to be safe

12Z GFS is predicting 29F at Bush airport (IAH) on Tuesday morning as the second Arctic high settles in over TX. Fine with me, as I have Nov. 21st as the first freeze date in our office contest and no one has an earlier date. I've been trying to win one of these contests for 15+ years. Almost won the first cold front contest but the required 49F dew point at IAH didn't occur until 1 hour too late for me to win.

So, to help things along I've temporarily change my avatar to something that might encourage the cold air this weekend & early next week.

I screenshotted this for historical posterity!

[perk]

Get a good look,because after he pockets that contest money we'll never see it again.

[srainhoutx]

The coldest morning of the Fall season is in progress across SE Texas. Temperatures have fallen rather dramatically with the over night rain and is currently in the mid to upper 30's except right along the Coast where it is hovering around 40. Isolated sleet has fallen overnight across portions of the Hill Country and N Texas while light snow is falling across the Panhandle into Kansas and Oklahoma. The upper air disturbance in association with an Eastern Pacific tropical disturbance that moved inland and crossed Mexico is responsible for the overnight moisture. Later today the Arctic High that ushered in all this cold weather will settle into Texas. Today will be a raw cold day across Texas. Skies may clear later today and winds relax allowing for ideal radiational cooling that will set the stage for freezing temperatures. Areas mainly along and N of I-10 may see freezing temperatures for about 10 hours. Closer to the Coast, freezing temps are possible for 3-5 hours.

Friday afternoon will begin a very short moderation period into Saturday as a Coastal Low develops near the Middle Texas Coast and the high pressure responsible for the cold air slides off to the E. The upper air pattern remain well in tack, so this very brief reprieve will not last. Saturday afternoon/night as the Coastal Low develops and yet another disturbance arrives from the Pacific NW elevated rain chances begin. There is a chance that a warm front may attempt to develop along the Coast and thunderstorms may be possible S of that boundary. Moisture will increase as uplift from the inbound upper air disturbance and the Coastal Low matures Saturday night, to very wet conditions are likely. To our N across Canada, a powerful upper low/trough is dropping S and will enter Montana Saturday night ushering in another Arctic Blast into the Plains. A strong cold front will follow the Coastal low and upper air feature as they move E of Sunday.

The next in a series of upper air disturbances will move inland across California and rapidly progress E along the base of the deep trough Sunday night. The cold Arctic air will have already arrived setting the stage for a Winter Weather potential across the Southern/Central Plains and at least the northern half of Texas. Precipitation amounts are expected to be light with this disturbance, but there is some disagreement with the guidance as to the strength of the disturbance. As we witnessed overnight, the computer models are having a very difficult time with this unusual pattern and the magnitude of the cold air. Monday night may bring even colder air than tonight with a more prolonged period of below freezing temperatures if the GFS solutions are correct with a slower moving disturbance Sunday night into Monday morning. Stay Warm. Things look to finally begin to moderate by mid to late next week.

[somethingfunny]

Dennis Cavanaugh delivers the goods with his AFD from Fort Worth today:

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE FORT WORTH TX
524 AM CST THU NOV 13 2014

.AVIATION...
/12Z TAFS/

VFR CONDITIONS WILL PREVAIL WITH CLOUDS AROUND 6-7 KFT. BREEZY
WINDS BETWEEN 12-17 KTS WITH SLIGHTLY HIGHER GUSTS WILL PREVAIL
TODAY BUT WIND SPEEDS WILL DROP TO LESS THAN 10 KTS JUST BEFORE
SUNSET THIS EVENING. LIGHT NORTH WINDS THROUGH THE NIGHT WILL
BECOME SOUTHEAST BY MIDDAY FRIDAY. TEMPERATURES WILL FALL BELOW
FREEZING THIS EVENING AND CONTINUE DROPPING INTO THE TEENS AND 20S
OVERNIGHT.

82/JLD

&&

.PREV DISCUSSION... /ISSUED 356 AM CST THU NOV 13 2014/

09Z/3AM REGIONAL RADARS CONTINUED TO SHOW ISOLATED POCKETS OF
SLEET DEVELOPING AND MOVING EAST ROUGHLY ALONG A LINE FROM SULPHUR
SPRINGS TO GRANBURY TO COMANCHE. SOCIAL MEDIA REPORTS FROM THE
PUBLIC INDICATE THAT THIS PRECIPITATION IS GENERALLY ONLY STICKING
AROUND ON GRASSY AREAS...AND IS NOT COMPLETELY COATING THE GROUND.
THIS LIGHT PRECIPITATION APPEARS TO BE WELL CORRELATED WITH A ZONE
OF FRONTOGENESIS NEAR THE 700 MB LEVEL. THE 00Z FWD SOUNDING
INDICATED THAT THERE WAS SOME MID-LEVEL MOISTURE IN PLACE ACROSS
THE REGION...GENERALLY LOCATED FROM 800 MB UP TO THE 600 MB LEVEL.
THE SOUNDING ALSO INDICATED THAT AIR LIFTED FROM JUST BELOW THE
700 MB LEVEL WAS CONDITIONALLY UNSTABLE...WHICH IS SUPPORTED BY
THE CELLULAR APPEARANCE OF LIGHT PRECIPITATION ON AREA RADARS.
MODELS INDICATE THAT THIS ZONE OF LIFT ALOFT WILL MOVE EAST OF THE
CWA SHORTLY AFTER SUNRISE IN CONCERT WITH A SHORTWAVE TROUGH THAT
WAS LOCATED NEAR DEL RIO ACCORDING TO WATER VAPOR SATELLITE
IMAGERY. AS A RESULT...WILL NOT CARRY ANY MENTION OF SLEET INTO
THE FORECAST ACROSS NORTH TEXAS THIS MORNING AS THIS PRECIPITATION
IS EXPECTED TO HAVE MOVED OFF TO THE EAST SHORTLY AFTER 12Z.

FOR TODAY...THE DEL RIO SHORTWAVE TROUGH IS EXPECTED TO CONTINUE
MOVING EAST OVER SOUTH TEXAS TODAY...RESULTING IN LARGE SCALE
FORCING FOR SUBSIDENCE OVER MUCH OF THE CWA. THIS SHOULD RESULT IN
CLEARING SKIES FROM THE NORTHWEST TO SOUTHEAST BY THIS AFTERNOON.
DESPITE THE PROSPECT FOR CLEARING SKIES...TEMPERATURES ARE
EXPECTED TO REMAIN VERY COOL TODAY AS STRONG LOW-LEVEL COLD AIR
ADVECTION CONTINUES THROUGHOUT THE DAY. MODELS CONTINUE TO
ADVERTISE NEAR RECORD LOW 850 MB TEMPERATURES (ACCORDING TO THE
SPC SOUNDING CLIMATOLOGY PAGE) OVER NORTH TEXAS TODAY...WHICH WILL
HELP KEEP TODAYS HIGHS IN THE UPPER 30S TO LOW 40S EVEN WITH SOME
SUNSHINE THIS AFTERNOON. PRECIPITATION CHANCES ARE REALLY JUST
TIED TO THE LINE OF ISOLATED SLEET MENTIONED ABOVE...ONCE THAT IS
CLEAR/EAST OF THE CWA CONFIDENCE IN A DRY FORECAST FOR THE REST OF
THE DAY IS VERY HIGH.

TONIGHT...A RELATIVELY STRONG SHORTWAVE TROUGH CURRENTLY LOCATED
JUST OFFSHORE THE NORTHWEST CONUS COAST WILL MOVE SOUTHEAST OVER
THE CENTRAL PLAINS AS ANOTHER STRONG SHORTWAVE TROUGH APPROACHES
THE CALIFORNIA COAST. WHILE THIS FIRST TROUGH IS EXPECTED TO DUMP
A DECENT AMOUNT OF SNOW OVER THE NORTHWESTERN CONUS...AS IT MOVES
OVER THE CENTRAL PLAINS TONIGHT IT WILL HELP STRENGTHEN LEE-SIDE
CYCLOGENESIS OVER THE SOUTHERN HIGH PLAINS. THIS WILL FINALLY
PUT AN END TO THE PERSISTENT STRONG COLD AIR ADVECTION THAT HAS
BEEN IN PLACE OVER THE REGION FOR THE PAST COUPLE OF DAYS BY
HELPING TO PUSH THE STRONG SURFACE HIGH/ANTI-CYCLONE OFF TO THE
EAST OF THE REGION. AS THIS OCCURS OVERNIGHT...THE SURFACE RIDGE
AXIS IS EXPECTED TO MOVE DIRECTLY OVER THE CWA RESULTING IN VERY
LIGHT WINDS AFTER MIDNIGHT. UNDER MOSTLY CLEAR SKIES...WINDS
BECOMING LIGHT WILL SET UP AN IDEAL ENVIRONMENT FOR RADIATIONAL
COOLING WHICH SHOULD ALLOW TEMPERATURES ACROSS THE AREA TO DROP
WELL BELOW FREEZING. MOST LOCATIONS ARE EXPECTED TO FALL INTO THE
MID TO UPPER 20S TONIGHT. WHATEVER LOCATIONS HAVE NOT FALLEN BELOW
FREEZING BY THIS MORNING WILL NEED TO BE INCLUDED IN A FREEZE
WARNING FOR TONIGHT/TOMORROW MORNING AS CONFIDENCE IN A CWA-WIDE
FREEZE IS VERY HIGH.

SATURDAY...WINDS ARE EXPECTED TO RETURN TO THE SOUTHEAST AS HIGH
PRESSURE CONTINUES OFF TO THE EAST OF THE AREA. THE CALIFORNIA
SHORTWAVE TROUGH IS EXPECTED TO MOVE OVER THE SOUTHERN PLAINS ON
SATURDAY RESULTING IN STRONG WARM-AIR ADVECTION AND SOME RETURN OF
GULF MOISTURE TO THE AREA. WHILE MOISTURE RETURN IS NOT EXPECTED
TO BE DEEP...BECAUSE WE HAVE BEEN SO ABNORMALLY COOL THE PAST
COUPLE OF DAYS...LOW-LEVEL ISENTROPIC SURFACES ARE SOMEWHAT STEEP
AND STRONG UPGLIDE IS EXPECTED THROUGHOUT THE DAY ON SATURDAY AS A
RESULT. SHALLOW MOISTURE RETURN WITH THIS PERSISTENT ISENTROPIC
UPGLIDE IS EXPECTED TO RESULT IN ON-AND-OFF LIGHT RAIN ON
SATURDAY...MORE LIKELY EAST OF INTERSTATE 35 WHERE MOISTURE RETURN
AND ISENTROPIC LIFT ARE STRONGEST IN MODEL GUIDANCE.

THE CALIFORNIA SHORTWAVE TROUGH IS EXPECTED TO MOVE EAST OF THE
CWA BY SUNSET SATURDAY...RESULTING IN SOME LARGE SCALE FORCING FOR
SUBSIDENCE OVER THE AREA IN ITS WAKE. THIS WILL CAUSE CLOUDS TO
CLEAR A BIT TEMPORARILY OVER THE WESTERN CWA SATURDAY
AFTERNOON...ALLOWING TEMPERATURES TO CLIMB INTO THE LOWER TO MID
50S. FOR THE REST OF THE AREA...SUBSIDENCE IS EXPECTED TO BE TOO
BRIEF TO RESULT IN A COMPLETE CLEARING OF CLOUDS...WHICH SHOULD
KEEP TEMPERATURES IN THE MID TO UPPER 40S SATURDAY AFTERNOON WITH
RAIN CHANCES MOVING EAST THROUGHOUT THE DAY.

SATURDAY NIGHT AND SUNDAY...A COLD FRONT IS EXPECTED TO MOVE SOUTH
ACROSS THE SOUTHERN PLAINS SATURDAY NIGHT BEHIND SATURDAYS
SHORTWAVE TROUGH. THE SPEED OF THE FRONT MOVING SOUTH ACROSS THE
CWA IS SOMEWHAT DEPENDENT UPON THE EVOLUTION OF A POWERFUL UPPER
LEVEL LOW PRESSURE SYSTEM APPROACHING THE REGION FROM THE NORTH.
THIS LOW PRESSURE SYSTEM WAS STILL OVER THE NORTHWEST TERRITORIES
OF CANADA...ALMOST 2000 MILES AWAY FROM NORTH TEXAS. THIS UPPER
TROUGH IS EXPECTED TO SINK SOUTH OVER THE CONUS ROCKIES SATURDAY
NIGHT BEFORE ROUNDING OUT OVER NEW MEXICO AND HEADING EAST OVER
TEXAS LATE ON SUNDAY. THE MORE PROGRESSIVE AND WEAKER THIS UPPER
LEVEL TROUGH IS BY THE TIME IT STARTS MOVING EAST ON SUNDAY...THE
FASTER THE FRONT WILL PUSH ACROSS NORTH TEXAS. IN GENERAL...A
FASTER FRONTAL PASSAGE RESULTS IN LOWER PRECIPITATION CHANCES.

THE GFS SEEMS TO BE HOLDING ON TO THE STRONGER AND SLOWER SOLUTION
COMPARED TO THE ECMWF AND CANADIAN SOLUTIONS. IF THE UPPER TROUGH
IS SLOWER AND STRONGER...IT WILL INDUCE WARM AIR ADVECTION AND
ISENTROPIC LIFT THROUGH A DEEPER LAYER OF THE TROPOSPHERE
RESULTING IN STRONGER LIFT...AND A BETTER CHANCE FOR MOISTURE TO
GET WRAPPED UP INTO THIS SYSTEM. BECAUSE THE GFS HAS BEEN FAIRLY
CONSISTENT IN ITS HANDLING OF THIS UPPER LEVEL TROUGH COMPARED TO
THE ECMWF AND CANADIAN...THIS FORECAST IS HEDGED TOWARDS THIS
STRONGER GFS SOLUTION.

IN THE FORECAST...MAINTAINED LOW RAIN CHANCES ASSOCIATED WITH THE
FRONT MOVING ACROSS THE CWA FROM EARLY SUNDAY MORNING THROUGHOUT
THE DAY ON SUNDAY. FROM LATE SUNDAY AFTERNOON THROUGH SUNDAY NIGHT
IS WHEN THINGS GET MORE INTERESTING BECAUSE TEMPERATURES FALL
BELOW FREEZING WHILE POTENTIALLY STRONG LIFT ASSOCIATED WITH THE
UPPER TROUGH MOVES OVER THE CWA. AT THIS TIME HAVE 20-30 POPS IN
THE FORECAST ACROSS THE ENTIRE CWA...WITH PRECIPITATION
TRANSITIONING OVER FROM LIGHT RAIN TO LIGHT SNOW FROM THE
NORTHWEST TO THE SOUTHEAST AFTER 00Z MONDAY (SUNDAY EVENING).

AT THIS TIME...ANY WINTRY PRECIPITATION LOOKS TO REMAIN
LIGHT...AND HAVE LESS THAN A HALF OF AN INCH OF SNOW IN THE
FORECAST ACROSS NORTH TEXAS SUNDAY EVENING/OVERNIGHT. HOWEVER...IT
IS VERY DIFFICULT TO DETERMINE THE POTENTIAL FOR MESOSCALE
ENHANCEMENT TO PRECIPITATION THIS FAR OUT IN THE FORECAST.
FORECAST SOUNDINGS DO INDICATE THAT CONDITIONAL INSTABILITY EXISTS
IN THE DENDRITIC GROWTH ZONE (-12 TO -18 DEG C LAYER) ALOFT...SO
THERE CERTAINLY IS THE POTENTIAL FOR MESOSCALE ENHANCEMENT
(BANDING) IF SUFFICIENT CONDITIONS ARE MET. THERE IS TOO MUCH
UNCERTAINTY TO GET INTO THE DETAILS THIS FAR OUT...BUT WE WILL
HAVE TO CLOSELY DIAGNOSE THE MESOSCALE ENVIRONMENT IN LATER
FORECASTS IF IT LOOKS LIKE THE GFS FORECAST IS STILL ON TRACK AT
THAT TIME.

MONDAY THROUGH WEDNESDAY...AT THIS TIME THE CONSENSUS OF GUIDANCE
IS FOR A COOL AND DRY FORECAST BEHIND SUNDAY/SUNDAY NIGHTS
POWERFUL UPPER TROUGH. MADE NO SIGNIFICANT CHANGES TO THE PREVIOUS
FORECAST AS A RESULT.

CAVANAUGH

[weatherdude1108]

32.8 at 6:20am at the Weatherdude casa. High today is predicted to be 41!

Normal LOW is 48. Wow.

[srainhoutx]

Morning briefing from Jeff:

***Freeze Warning in effect for tonight and Friday morning for all SE TX counties except along the immediate coast***

***Freeze Watch in effect for the coastal counties will likely be upgraded to a freeze warning this afternoon.***

A couple degrees away from a big mess this morning with the light to moderate rain falling into a very cold surface layer with temperature hovering in the 34 to 38 degree range. Short wave responsible for the large area of rain overnight is quickly moving eastward with back edge of the light rain along US 59 currently. Should see all precipitation end by 900am for most areas. Clouds will remain most of the day and with strong cold air advection continuing there will be very little temperature recovery today. Highs in the mid 40’s look reasonable for most areas.

Upstream air mass is bitter cold with Denver currently at -11 and Casper at -15 which is breaking 70 year old records this morning. Amarillo has fallen to 14 this morning after a high on Wednesday of only 21. To give an idea of just how impressive this arctic outbreak has been: Borger, TX had a record high of 85 on Monday ahead of the front and recorded a record low of 15 degrees yesterday morning which equates to a 70 degree temperature change in a little over 24 hours.

Tonight/Friday morning:
Very cold arctic air mass with large arctic high over the plains will continue to build into TX. Shortwave exiting to the east will allow skies to clear late this afternoon and with low dewpoints in place and winds decreasing a widespread killing freeze is likely over much of SE TX Friday morning. Expected morning lows for Friday morning:

N of HWY 105: 25-28
N of US 59: 29-32
Inside Beltway 8: 30-32
Interior coastal counties: 30-33
Immediate coast: 35-38

Duration of sub-freezing temperatures will be on average 8-12 hours north of I-10 and 4-8 hours elsewhere across the region where the temperatures fall to freezing.

Temperatures of this magnitude will effectively end the growing season and result in damage to sensitive vegetation and citrus that is not protected. Exposed outside pipes should be protected, but do not expect any big concerns with damage to pipes as we are currently not looking at a prolonged hard freeze.

Weekend:
Strong short wave moves across TX Saturday and Saturday night forcing a coastal trough over the lower TX coast that moves northward on Saturday. Moisture rapidly increases over the surface cold dome resulting in increasing rain chances. Clouds will begin to increase from SW to NE Saturday morning with showers developing by mid to late afternoon. Warm front will approach the coastal counties and may move inland Saturday evening and Saturday night with a heavy rainfall and strong thunderstorm threat along and south of US 59. Coastal low heads for SW LA early Sunday with another dump of very cold arctic air into the region and off the coast. Temperatures will be tricky on Saturday as strong warm air advection tries to erode the arctic dome in place. Models are usually too aggressive in eroding shallow cold arctic air and hence tend to be too warm in treating arctic air mass situations. Additionally the increasing clouds and rain will help to hold down the warning to advective processes only. The exception will be near the coast where the warm front may move inland allowing a warm humid air mass to push onshore. Could be a fairly significant temperature gradient across the area Saturday evening with near 70 at the coast to the 40’s inland. As the coastal low moves east on Sunday the next dump of arctic air will keep temperatures steady or falling into the 40’s during the day.

Models want to bring another disturbance across TX in the cold air Sunday night into Monday with winter precipitation across the northern portions of the state. Not sure how much moisture will be available by Sunday night into Monday as the upstream air mass is very dry, but this is something to keep an eye on over the next 48 hours.

Next cold air surge looks to be even colder than the current one with widespread freezing temperatures possible by next Tuesday morning. Guidance is already showing lows into the 20’s by the middle of next week and this far out is usually too warm.