January: Calmer Pattern To End The Month

[srainhoutx]

The 15Z SREF ensemble individual members suggest a fairly widespread Winter Weather Event potential across the Southern half of Texas.

[srainhoutx]

HGX will issue a Winter Storm Watch shortly.

[srainhoutx]

PROBABILISTIC HEAVY SNOW AND ICING DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
401 PM EST WED JAN 22 2014

VALID 00Z THU JAN 23 2014 - 00Z SUN JAN 26 2014


...ROCKIES INTO TEXAS...

A SHORTWAVE TROUGH NEAR THE NRN ROCKIES/INTERIOR NW WILL DIVE
SOUTHEASTWARD TOWARD THE CENTRAL ROCKIES ON THURS. MOISTURE
AVAILABILITY WITH THIS SYSTEM WILL NOT BE IN ABUNDANCE...BUT
SUFFICIENT FORCING AND UPSLOPE FLOW WILL SUPPORT SOME SNOWFALL
ACROSS MAINLY ERN COLORADO INTO NERN NEW MEXICO. MEANWHILE... A
MAMMOTH COLD ANTICYCLONE WILL BASE ITSELF OVER THE MIDWEST AND
EXTEND AS FAR SOUTH AS TEXAS. ERLY FLOW OFF THE GULF OF MEXICO
WILL SETUP TO USHER SOME MOISTURE INLAND ACROSS TEXAS AND THIS
VERY WELL COULD SET THE STAGE FOR SNOW/SLEET AND LIGHT ICING FROM
LATE THURS TO MIDDAY FRI. THE SHALLOW AND DENSE COLD AIR MASS WILL
UNDERCUT THE MID-LEVEL WARMING AND ONSHORE MOIST FLOW FOR THE
THREAT OF FROZEN PRECIP AND MINIMAL QPF AMOUNTS FROM THE SRN HILL
COUNTRY TO SERN TX. WPC FOLLOWED THE MORE CONSISTENT AND
CONSERVATIVE APPROACH OF THE GFS AND ECMWF OVER THE MUCH MORE BOLD
NAM AND ISSUED A LOW PROB OF 4 INCHES OF SNOW... THOUGH IT IS
HIGHLY UNLIKELY EITHER THAT MUCH SNOW OR .25 INCH ICING WILL BE
MET. THUS EVEN THOUGH AMOUNTS APPEAR NOT TO BE
SIGNIFICANT...HAZARDOUS DRIVING CONDITIONS WILL BE LIKELY FOR AN
AREA OF THE COUNTRY NOT VERY USED TO FROZEN PRECIP.

THE PROBABILITY OF SIGNIFICANT ICING IS LESS THAN 10 PERCENT FOR
ALL 3 DAYS.

MUSHER

[unome]

does the County or State use chemicals on bridges/overpasses? it's looking more & more like it might be needed

slide to 3 AM Friday & check out the weather http://preview.weather.gov/graphical/?z ... ts=english

[srainhoutx]

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
310 PM CST WED JAN 22 2014

...WINTER STORM WATCH IN EFFECT FOR MOST OF SOUTHEAST TEXAS...

A COLD FRONT WITH AN ARCTIC AIRMASS BEHIND IT WILL MOVE INTO
SOUTHEAST TEXAS ON THURSDAY. TEMPERATURES WILL HOLD STEADY AND
THEN BEGIN TO FALL DURING THE DAY. TEMPERATURES SHOULD DROP BELOW
FREEZING THURSDAY NIGHT INTO FRIDAY MORNING. MOISTURE RIDING OVER
THE FRONTAL BOUNDARY WILL PRODUCE AREAS OF RAIN DURING THE DAY
THURSDAY. PRECIPITATION MAY THEN CHANGE FROM RAIN TO FREEZING RAIN
AND SLEET. AREAS FROM COLLEGE STATION TO HUNTSVILLE MAY EXPERIENCE
A MIX OF SNOW AND SLEET EARLY FRIDAY. AREAS TO THE SOUTH INCLUDING
HOUSTON MAY EXPERIENCE A MIX OF SLEET AND FREEZING RAIN WITH
FREEZING RAIN POSSIBLE ALONG THE COAST. WINTER STORM WARNINGS AND
ADVISORIES MAY BE ISSUED DEPENDING ON EXPECTED ICE ACCUMULATIONS
EXPECTED IN THE WATCH AREA.

TXZ176>178-195>200-210>214-226-227-235>238-231000-
/O.NEW.KHGX.WS.A.0001.140124T0600Z-140124T2100Z/
AUSTIN-BRAZORIA-BRAZOS-BURLESON-CHAMBERS-COLORADO-FORT BEND-
GALVESTON-GRIMES-HARRIS-JACKSON-LIBERTY-MADISON-MATAGORDA-
MONTGOMERY-SAN JACINTO-WALKER-WALLER-WASHINGTON-WHARTON-
INCLUDING THE CITIES OF...ALVIN...ANAHUAC...ANGLETON...BAY CITY...
BELLVILLE...BRENHAM...BROOKSHIRE...BRYAN...CALDWELL...CLEVELAND...
COLDSPRING...COLLEGE STATION...COLUMBUS...CONROE...DAYTON...
EAGLE LAKE...EDNA...EL CAMPO...FREEPORT...FRIENDSWOOD...
GALVESTON...HEMPSTEAD...HOUSTON...HUMBLE...HUNTSVILLE...KATY...
LAKE JACKSON...LAKE SOMERVILLE...LEAGUE CITY...LIBERTY...
MADISONVILLE...MISSOURI CITY...MONT BELVIEU...NAVASOTA...
PALACIOS...PASADENA...PEARLAND...PIERCE...PRAIRIE VIEW...
RICHMOND...ROSENBERG...SEALY...SHEPHERD...SUGAR LAND...
TEXAS CITY...THE WOODLANDS...TOMBALL...WEIMAR...WHARTON...
WILLIS...WINNIE
310 PM CST WED JAN 22 2014

...WINTER STORM WATCH IN EFFECT FROM LATE THURSDAY NIGHT THROUGH
FRIDAY AFTERNOON...

THE NATIONAL WEATHER SERVICE IN HOUSTON/GALVESTON HAS ISSUED A
WINTER STORM WATCH...WHICH IS IN EFFECT FROM LATE THURSDAY NIGHT
THROUGH FRIDAY AFTERNOON.

* TIMING...MAINLY EARLY FRIDAY MORNING THROUGH FRIDAY AFTERNOON.
PORTIONS OF THE WATCH MAY BE UPGRADED TO A WARNING TOMORROW
WHERE AREAS MAY RECEIVE MORE THAN A EIGHTH OF AN INCH OF ICE
ACCUMULATIONS. ADVISORIES MAY REPLACE PORTIONS OF THE WATCH
WHERE ICE ACCUMULATIONS WILL BE LOWER.

* THREAT...ICE ACCUMULATIONS FROM SLEET OR FREEZING RAIN OF 0.05 TO
0.15 INCHES.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WATCH MEANS THERE IS A POTENTIAL FOR SIGNIFICANT
SNOW...SLEET...OR ICE ACCUMULATIONS THAT MAY IMPACT TRAVEL.
CONTINUE TO MONITOR THE LATEST FORECASTS.

[srainhoutx]

For the San Antonio/Austin area:

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
333 PM CST WED JAN 22 2014

.SHORT TERM (TONIGHT THROUGH THURSDAY NIGHT)...
LOW LEVEL RETURN FLOW IS WELL UNDER WAY THIS AFTERNOON WITH
TEMPERATURES WARMING INTO THE 60S AND LOW 70S. MUCH WARMER TONIGHT
WITH LOWS GENERALLY IN THE 40S...TO UPPER 30S NORTH. THE LEADING
EDGE OF THE ARCTIC COLD FRONT DROPPING INTO NORTH TX WILL CONTINUE
TO NEAR THE NRN CWA BY MIDNIGHT AND THEN PUSH THRU MUCH OF THE CWA
BY SUNRISE THURSDAY. NELY WINDS OF 15-25 MPH GUSTS TO 35 MPH WILL
RESULT IN STRONG COLD AIR ADVECTION ACROSS S TX DURING THE DAY
THURSDAY WITH FALLING OR STEADY TEMPERATURES. COMBINATION OF
ISENTROPIC LIFT ABOVE THE COLD AIR MASS AND MINOR DISTURBANCES
IN THE WESTERLY FLOW ALOFT WILL RESULT IN INCREASING CHANCES OF
PRECIPITATION. DEVELOPING LIGHT RAIN IN THE MORNING WILL CHANGE
OVER TO A MIX OF SLEET AND SNOW ACROSS THE HILL COUNTRY DURING THE
AFTERNOON AND SPREAD SOUTHWARD THURSDAY NIGHT. HAVE ISSUED A
WINTER WEATHER ADVISORY FOR THE HILL COUNTRY AND EDWARDS PLATEAU
BEGINNING AT NOON THURSDAY THRU MIDNIGHT...ALTHOUGH DO NOT EXPECT
ANY ACCUMULATIONS UNTIL THURSDAY EVENING AS SURFACE TEMPERATURES
DROP BELOW FREEZING. A WINTER STORM WATCH IS IN EFFECT FOR ALL OF
THE HILL COUNTRY AND SOUTH CENTRAL TEXAS FROM MIDNIGHT THURSDAY
THRU NOON FRIDAY AS STORM TOTAL ACCUMULATIONS OF ONE HALF TO ONE
INCH POSSIBLE ACROSS THE HILL COUNTRY...WITH A TRACE TO ONE HALF
INCH ACROSS THE ADJACENT AREAS. AREAS ALONG AND SOUTH OF HIGHWAY
90 WEST OF SAN ANTONIO AND I10 EAST OF SAN ANTONIO COULD SEE LIGHT
ICE ACCUMULATIONS FROM LIGHT FREEZING RAIN OF ONE-TWO TENTHS OF AN
INCH. THE DEPTH OF FREEZING AIR WILL BE MORE SHALLOW ACROSS THIS
AREA AND MORE SUSCEPTIBLE TO A WINTRY MIX OF WINTER PRECIPITATION
INCLUDING FREEZING RAIN.

THE 18Z NAM/12Z NMM-EAST HAVE THE HIGHER STORM TOTAL QPF/SNOW
AMOUNTS WITH SOME 1-2 INCH/1-3 INCH AMOUNTS ACROSS THE HILL
COUNTRY RESPECTIVELY. THE 12Z ARW-EAST/GFS/ECMWF ALL INDICATE MUCH
LIGHTER AMOUNTS GENERALLY LESS THAN ONE QUARTER INCH OVER THE
NORTHERN HILL COUNTRY.

[cristina6871]

what are the chances, if any, that the green section (ice and flurries) could inch down further south?

[jasons2k]

does the County or State use chemicals on bridges/overpasses? it's looking more & more like it might be needed

Yes, TXDOT will spray bridges and overpasses on the main arteries ahead of time. Secondary roads will be sanded by the county/city.

[ticka1]

by this time tomorrow this event will be unfolding...driving in tomorrow dont trust metro getting me back home

[unome]

does the County or State use chemicals on bridges/overpasses? it's looking more & more like it might be needed

Yes, TXDOT will spray bridges and overpasses on the main arteries ahead of time. Secondary roads will be sanded by the county/city.

thanks Jason, good to know this !

[srainhoutx]

Update from Jeff:

Winter Storm Watch issued for much of SE TX from Thursday night into Friday.

Ingredients continue to come together to produce a period of winter precipitation across SE TX from Thursday night into midday/early afternoon on Friday.

Discussion:
Arctic cold front moving down the plains will blast off the TX coast on Thursday ushering in a very cold air mass. Temperatures will fall quickly behind the front into the 30’s for most area by sunset and to near freezing by mid evening from Brenham to Conroe to Lake Livingston. Strong cold air advection will push the freezing line southward overnight Thursday into Friday morning into the US 59 corridor around of shortly after midnight and then to the coast by early Friday morning. While this happens, an upper level storm system WSW of TX will begin to pump moisture northward into the cold air mass producing the potential for a mix of winter precipitation across much of the area from late Thursday into the early afternoon on Friday.

P-type:
Forecast models have not changed much with respect to the thermal profiles across the area today and expect the main P-type to be freezing rain with a warm layer of air aloft over top of a freezing surface layer. At times during the event, the warm layer aloft may shrink enough to allow sleet to mix with the freezing rain or change the freezing rain to sleet. Soundings are not very favorable for snowfall production with little moisture noted in the crystal growth layer and most of the area likely having too big a warm nose aloft for snow to make it to the surface. With that said, it may be a little close across areas NW of a line from about Columbus to Huntsville where sleet and freezing rain may mix with or at times change to snow.

Accumulation:
Since it appears a freezing rain or freezing rain/sleet mixture is the preferred P-type at the moment we can start to fine tune the accumulations some. Forecast models are still not in great agreement on liquid amounts ranging from trace amounts to amounts upwards of .25 of an inch. Dry air will be fighting the returning moisture from NE to SW so think the greatest amounts will be SW of a line from Brenham to Houston to Galveston. Freezing rain is a fairly simple ratio to liquid…pretty much what falls tends to be close to the ice accumulation. Now mixing with sleet can change the accumulation some, but do not think this will make too much different with this event.

Expect accumulation amounts to range from .05 to .10 of an inch in the Winter Storm Watch area and .10 to .20 of an inch along the US 59 corridor from SW Houston to near Victoria where the models are coming into some agreement on this being the favored area for precipitation.

Think there will continue to be some changes on the accumulation amounts tomorrow….but for today so far things have remained fairly stable.

Warm up on Friday looks very slow and areas may struggle to get to freezing or much above…so improvements on roadways will likely be very slow.

Impacts:
Freezing rain is about the worst winter precipitation you can ask for…as it glazes over objects and makes travel extremely hazardous.

Expect problems to develop from NW to SE across the region on bridges and overpasses from midnight Friday into mid morning Friday as the freezing line moves southward. Given warm ground temperatures do not expect ice accumulation on surface streets in contact with the ground…but all overpasses, bridges, ramps, and flyovers are at risk. Past experience with freezing rain and roadway icing suggest that temperatures either need to be below freezing for a period of time or fall into the 20’s to really start to see problems and I suspect this event will be no different.

Do not expect enough ice accumulation to result in widespread power outages. Could see a few tree limbs accumulate enough ice to touch power lines and cause localized outages, but most vegetation is defoilaged at this time which will reduce the surface area of ice accumulation.

Aviation travel will be impacted with required de-icing procedures so expect some lengthy delays.

Will update again tomorrow morning

[sambucol]

Anyone hearing from their school districts about possible closings Friday?

[cperk]

Anyone hearing from their school districts about possible closings Friday?

Probably won't start to here from school districts until tomorrow.

[Paul Robison]

Update from Jeff:

Winter Storm Watch issued for much of SE TX from Thursday night into Friday.

Ingredients continue to come together to produce a period of winter precipitation across SE TX from Thursday night into midday/early afternoon on Friday.

Discussion:
Arctic cold front moving down the plains will blast off the TX coast on Thursday ushering in a very cold air mass. Temperatures will fall quickly behind the front into the 30’s for most area by sunset and to near freezing by mid evening from Brenham to Conroe to Lake Livingston. Strong cold air advection will push the freezing line southward overnight Thursday into Friday morning into the US 59 corridor around of shortly after midnight and then to the coast by early Friday morning. While this happens, an upper level storm system WSW of TX will begin to pump moisture northward into the cold air mass producing the potential for a mix of winter precipitation across much of the area from late Thursday into the early afternoon on Friday.

P-type:
Forecast models have not changed much with respect to the thermal profiles across the area today and expect the main P-type to be freezing rain with a warm layer of air aloft over top of a freezing surface layer. At times during the event, the warm layer aloft may shrink enough to allow sleet to mix with the freezing rain or change the freezing rain to sleet. Soundings are not very favorable for snowfall production with little moisture noted in the crystal growth layer and most of the area likely having too big a warm nose aloft for snow to make it to the surface. With that said, it may be a little close across areas NW of a line from about Columbus to Huntsville where sleet and freezing rain may mix with or at times change to snow.

Accumulation:
Since it appears a freezing rain or freezing rain/sleet mixture is the preferred P-type at the moment we can start to fine tune the accumulations some. Forecast models are still not in great agreement on liquid amounts ranging from trace amounts to amounts upwards of .25 of an inch. Dry air will be fighting the returning moisture from NE to SW so think the greatest amounts will be SW of a line from Brenham to Houston to Galveston. Freezing rain is a fairly simple ratio to liquid…pretty much what falls tends to be close to the ice accumulation. Now mixing with sleet can change the accumulation some, but do not think this will make too much different with this event.

Expect accumulation amounts to range from .05 to .10 of an inch in the Winter Storm Watch area and .10 to .20 of an inch along the US 59 corridor from SW Houston to near Victoria where the models are coming into some agreement on this being the favored area for precipitation.

Think there will continue to be some changes on the accumulation amounts tomorrow….but for today so far things have remained fairly stable.

Warm up on Friday looks very slow and areas may struggle to get to freezing or much above…so improvements on roadways will likely be very slow.

Impacts:
Freezing rain is about the worst winter precipitation you can ask for…as it glazes over objects and makes travel extremely hazardous.

Expect problems to develop from NW to SE across the region on bridges and overpasses from midnight Friday into mid morning Friday as the freezing line moves southward. Given warm ground temperatures do not expect ice accumulation on surface streets in contact with the ground…but all overpasses, bridges, ramps, and flyovers are at risk. Past experience with freezing rain and roadway icing suggest that temperatures either need to be below freezing for a period of time or fall into the 20’s to really start to see problems and I suspect this event will be no different.

Do not expect enough ice accumulation to result in widespread power outages. Could see a few tree limbs accumulate enough ice to touch power lines and cause localized outages, but most vegetation is defoilaged at this time which will reduce the surface area of ice accumulation.

Aviation travel will be impacted with required de-icing procedures so expect some lengthy delays.

Will update again tomorrow morning

How many residences do you think will lose power thursday-friday, Jeff?

[jeff]

Update from Jeff:

Winter Storm Watch issued for much of SE TX from Thursday night into Friday.

Ingredients continue to come together to produce a period of winter precipitation across SE TX from Thursday night into midday/early afternoon on Friday.

Discussion:
Arctic cold front moving down the plains will blast off the TX coast on Thursday ushering in a very cold air mass. Temperatures will fall quickly behind the front into the 30’s for most area by sunset and to near freezing by mid evening from Brenham to Conroe to Lake Livingston. Strong cold air advection will push the freezing line southward overnight Thursday into Friday morning into the US 59 corridor around of shortly after midnight and then to the coast by early Friday morning. While this happens, an upper level storm system WSW of TX will begin to pump moisture northward into the cold air mass producing the potential for a mix of winter precipitation across much of the area from late Thursday into the early afternoon on Friday.

P-type:
Forecast models have not changed much with respect to the thermal profiles across the area today and expect the main P-type to be freezing rain with a warm layer of air aloft over top of a freezing surface layer. At times during the event, the warm layer aloft may shrink enough to allow sleet to mix with the freezing rain or change the freezing rain to sleet. Soundings are not very favorable for snowfall production with little moisture noted in the crystal growth layer and most of the area likely having too big a warm nose aloft for snow to make it to the surface. With that said, it may be a little close across areas NW of a line from about Columbus to Huntsville where sleet and freezing rain may mix with or at times change to snow.

Accumulation:
Since it appears a freezing rain or freezing rain/sleet mixture is the preferred P-type at the moment we can start to fine tune the accumulations some. Forecast models are still not in great agreement on liquid amounts ranging from trace amounts to amounts upwards of .25 of an inch. Dry air will be fighting the returning moisture from NE to SW so think the greatest amounts will be SW of a line from Brenham to Houston to Galveston. Freezing rain is a fairly simple ratio to liquid…pretty much what falls tends to be close to the ice accumulation. Now mixing with sleet can change the accumulation some, but do not think this will make too much different with this event.

Expect accumulation amounts to range from .05 to .10 of an inch in the Winter Storm Watch area and .10 to .20 of an inch along the US 59 corridor from SW Houston to near Victoria where the models are coming into some agreement on this being the favored area for precipitation.

Think there will continue to be some changes on the accumulation amounts tomorrow….but for today so far things have remained fairly stable.

Warm up on Friday looks very slow and areas may struggle to get to freezing or much above…so improvements on roadways will likely be very slow.

Impacts:
Freezing rain is about the worst winter precipitation you can ask for…as it glazes over objects and makes travel extremely hazardous.

Expect problems to develop from NW to SE across the region on bridges and overpasses from midnight Friday into mid morning Friday as the freezing line moves southward. Given warm ground temperatures do not expect ice accumulation on surface streets in contact with the ground…but all overpasses, bridges, ramps, and flyovers are at risk. Past experience with freezing rain and roadway icing suggest that temperatures either need to be below freezing for a period of time or fall into the 20’s to really start to see problems and I suspect this event will be no different.

Do not expect enough ice accumulation to result in widespread power outages. Could see a few tree limbs accumulate enough ice to touch power lines and cause localized outages, but most vegetation is defoilaged at this time which will reduce the surface area of ice accumulation.

Aviation travel will be impacted with required de-icing procedures so expect some lengthy delays.

Will update again tomorrow morning

How many residences do you think will lose power thursday-friday, Jeff?

562

[srainhoutx]

The 21Z SREF ensemble mean continues to advertise a prolonged light freezing rain/sleet event that finally begins to wind down Friday night/early Saturday morning. The 00Z NAM suggests a tab bit more moisture that comes to an end in SE Texas Friday afternoon/evening. Both of these shorter range meso models are suggesting a Coastal trough/low near Brownsville/Corpus Christi.

[srainhoutx]

NWS Corpus Christi issues Winter Storm Watch for Bee, Goliad, Refugio, Victoria & Calhoun Counties @ 8:50 PM CST

[skidog40]

Srain what is your feeling or opinion on what you think is coming.

[srainhoutx]

My hunch skidog is that we will likely see a light freezing rain/sleet event with a few snow flakes mixed in as the deeper cold air arrives. This type of setup is a classic NW Gulf Coast Winter Weather event and the trends suggest we may well see wintry weather across/Central Texas and along the Coastal Counties of Texas that may well extend into the SW Parishes of Louisiana.

[Ptarmigan]

This could be the most significant winter weather event since February 4, 2011.