TX Winter Wx Threat # 8--- TX Ice Storm

[jeff]

What a mess!!

Dangerous ice storm in progress across much of TX.

Ice Storm Warning in effect for the following counties in SE TX: Montgomery, Waller, Walker, Grimes, Trinity, Polk, San Jacinto, Washington, Brazos, Burleson, Austin, Colorado, Madison,

Winter Storm Watch issued for the following counties: Harris, Liberty, Fort Bend, Wharton including metro Houston.

Significant icing event likely across SE TX including metro Houston.

Discussion:

Icing already in progress over the N and W counties with Brenham reporting 30 with freezing rain (snow being reported is an ASOS malfunction) and Caldwell reporting 32 with freezing rain and sleet mix. Freezing line is progressing southward toward SE TX and expect all N and W counties to fall to freezing this morning with freezing rain starting in the Ice Storm Warning area. Accumulations of ice could reach 1/10 to 1/4 of an inch today which is well into the warning criteria for SE TX.

Tonight:

Next upper level impulse clearly seen on water vapor near Baja comes across tonight and Tuesday as temps. fall below freezing all the way to the coast. Expect widespread freezing rain and sleet with heavy icing. Will hit the Watch and Warning areas hard with 1/4 to 1/2 inch accumulation widespread with some locations getting up to 1.0 inch of ice.

Impacts:

Power and trees along with bridges and overpasses will be the big issues. Glazing should begin over the N and W this morning and spread SE through the day and into the night. Expect power outages to begin by Tuesday morning as ice accumulates on tree limbs and they begin to break and sag on power lines. Ice accumulation may be heavy enough to bring down power lines and large power transmission towers.

Travel:

Forget trying to drive. Once the freezing temps. onset the bridges and overpasses with begin to ice over. Expect all bridges and overpasses to be ice covered by Tuesday morning with accumulations starting on surface streets and freeway main lanes. Travel will be very difficult if not impossible Tuesday morning and only worsen as the day goes on as freezing/frozen precip. continues during the day.

Aviation:

Strict de-icing procedures will be going into effect at area terminals today. Heavy icing of aircraft controls can be expected through 2500 ft. Aircraft may be sent back to terminals multiple times to de-ice with very long delays and cancellations.

Response:

The state EOC is activated along with the TX National guard to assist in stranded motorist on ice covered roads across the state. Widespread power outages are already ongoing over N TX and NC TX where icing of .5 to 1.5 inches has occurred.

Forecast for Harris and Surrounding Counties:

Ice Storm Warning in effect

Winter Storm Watch in effect

Today: cloudy and very cold with temps. falling into the mid 30's. A 70% chance of morning rainfall changing to freezing rain late. N winds 15-25mph

Tonight: Ice Storm Conditions. Cloudy and very cold with temps falling into the upper 20's. A 70% chance of freezing rain and sleet. N winds 10-15mph. Ice accumulation of 1/4 to 1/2 of an inch.

Tuesday: Ice Storm Conditions. Cloudy and very cold with temps steady in the upper 20's to low 30's. A 70% chance of freezing rain and sleet. N winds 10-15mph. New ice accumulation of 1/4 to 1/2 of an inch.

Tuesday night: Ice Storm Conditions. Cloudy and very cold with a 40% chance of sleet and freezing rain. Temps. steady in the upper 20's. N winds 10-15mph. New ice accumulation of 1/8 th 1/4 of an inch.

Wednesday: Ice Storm Conditions. Cloudy and very cold with a 40% chance of freezing rain and sleet before noon. Temps. rising to near 34 by afternoon. Morning ice accumulation of less than 1/10 of an inch.

Thursday: Cloudy and very cold with a 30% chance of rain. Lows near 31 and highs near 38.

Friday: cloudy and very cold with a 30% chance of rain. Lows near 33 and highs near 42.

Next update will be around 1000am

[Tamora]

23.9 in Mansfield at 7:26. I am curious how cold it got last night. Sheet of ice on sidewalks. Way to cold to check the roads
Thank goodness MISD is closed due to MLK holiday. Come May, I really don't like giving up my snow day in January.

[gboudx]

About 0.25" of ice on everything here, including the street. Apparently, we had a good bit of sleet mixed in with the rain last night.

[JenBayles]

Pretty nasty under the Bear Creek Dome this morning (massive Dome failure since 2:00 a.m. by the way!) with temps in the upper 30's breezy, and waves of rain moving through.

I'm supposed to drive to Katy today to help out my brother's family, and wondering if I should cancel? Guess I'll just have to keep an eye out and adopt the usual "wait and see" position. <sigh> Sure wish weather could be an exact science!

[ROCK]

Pretty nasty under the Bear Creek Dome this morning (massive Dome failure since 2:00 a.m. by the way!) with temps in the upper 30's breezy, and waves of rain moving through.

I'm supposed to drive to Katy today to help out my brother's family, and wondering if I should cancel? Guess I'll just have to keep an eye out and adopt the usual "wait and see" position. <sigh> Sure wish weather could be an exact science!

if your going to go Go now!......be back before sunset is my advice...

[cheezyWXguy]

Yep we finally got ours...anywhere from 1/10th -1/4th of an inch here, this is the definition of black ice...if you looked out your window you would not think it iced last night...but my driveway is covered with at least a 1/4 inch of ice

[Kelarie]

In Austin, there have been over 66 wrecks since midnight. That was the last figure I heard. There was an 8 car pile up on 183 and ice was suspected.

There is something falling from the sky right now, it is light and white.

[Kelarie]

San Antonio/Austin NWS

DISCUSSION...
THE TROPICAL MOISTURE CONTINUES TO STREAM OVER THE COLD ARCTIC AIRMASS AT THE SURFACE. WITH THE CONTINUAL STREAM OF COLDER ARCTIC AIR TODAY, TEMPS WILL RISE ONLY A FEW DEGREES ABOVE WHAT WE HAVE RIGHT NOW. THE CONTINUOUS STREAM OF TROPICAL MOISTURE ABOVE THIS LAYER WILL FALL IN THE FORM OF RAIN AND FREEZING THROUGH TONIGHT. THE PRECIP WILL TRANSITION OVER TO SNOW AND SLEET AROUND MIDNIGHT TONIGHT AND CONTINUE THROUGH TUESDAY NIGHT. HOWEVER, A WEAK RIDGE ALOFT DEVELOPS TUESDAY NIGHT, LIMITING PRECIPITATION AMOUNTS. THEN ON WEDNESDAY AS THE ARCTIC AIRMASS DRIFTS EAST AND THE GROUND WARMTH MODIFIES IT FROM BELOW, THE PRECIP WILL SWITCH BACK TO REGULAR RAIN. HOWEVER, WINTRY PRECIP MAY RETURN LATER IN THE WEEK AS SURGE AFTER SURGE OF COLD AIRMASSES, AND CONTINUED SOUTHWEST FLOW ALOFT, MOVE INTO TEXAS.

[wxman57]

In Austin, there have been over 66 wrecks since midnight. That was the last figure I heard. There was an 8 car pile up on 183 and ice was suspected.

There is something falling from the sky right now, it is light and white.

I'm looking at the latest RUC sounding valid at 13Z for Austin. Shows a very shallow sub-freezing level about 2000 ft thick. Above that the temperature rises, up to 48 at 7000 ft and doesn't drop below freezing until 12000-13000 ft. So the only layer below freezing is right at the surface. 2000 feet seems low for snow to form. Could it be frozen drizzle? Unless the RUC soundings are way off....

[cheezyWXguy]

Yeah on saturday night we had a bit of freezing drizzle but I could have sworn it was light snow...

[JenBayles]

Whew! Dodged that bullet! My bro has people coser to his home helping out today so I am no longer needed. Good thing, as things look to deteriorate sooner rather than later. (Don't believe I just wrote that - surely that statement just strengthened the Bear Creek Dome.)

[Extremeweatherguy]

The Dallas short term forecasts I have seen have also mentioned light snow mixing in for their counties.

May be some of these reports really are true then?

From the Dallas short term outlook:

A WINTRY MIX OF FREEZING RAIN...SLEET AND LIGHT SNOW CONTINUES TO
SHIFT SLOWLY EAST AT 20 MPH. THE MAIN BAND OF A WINTRY MIXTURE WILL
SIT ALONG AND EAST OF A CAMERON...TO MARLIN...TO CORSICANA...TO
CANTON AND SULPHUR SPRINGS LINE THROUGH 10 AM. AN ADDITIONAL 1/10 TO
2/10 OF ICE ACCUMULATION EXPECTED ACROSS THIS AREA AND TRAVEL IS
HIGHLY DISCOURAGED. TEMPERATURES CONTINUE BETWEEN 27 AND 31 DEGREES
THROUGH LATE MORNING.

[JenBayles]

Just checked up the road in Brenham: 30 degrees with "unknown precip".

[BreinLa]

Amazing 46 degrees in Lake Charles and 70 degrees in Lafayette
http://sirocco.accuweather.com/nx_mosai ... SIRLA_.gif

don't think its snowing in Lake Charles tho lol

[wxman57]

The Dallas short term forecasts I have seen have also mentioned light snow mixing in for their counties.

May be some of these reports really are true then?

From the Dallas short term outlook:

A WINTRY MIX OF FREEZING RAIN...SLEET AND LIGHT SNOW CONTINUES TO
SHIFT SLOWLY EAST AT 20 MPH. THE MAIN BAND OF A WINTRY MIXTURE WILL
SIT ALONG AND EAST OF A CAMERON...TO MARLIN...TO CORSICANA...TO
CANTON AND SULPHUR SPRINGS LINE THROUGH 10 AM. AN ADDITIONAL 1/10 TO
2/10 OF ICE ACCUMULATION EXPECTED ACROSS THIS AREA AND TRAVEL IS
HIGHLY DISCOURAGED. TEMPERATURES CONTINUE BETWEEN 27 AND 31 DEGREES
THROUGH LATE MORNING.

Dallas is not Houston or Victoria. The sub-freezing layer in Dallas extends from the surface to about 7000 feet up. That's cold enough for snow in Dallas. But with above-freezing temperatues from the surface to 14,000 feet in our area we can't get snow.

[Portastorm]

In Austin, there have been over 66 wrecks since midnight. That was the last figure I heard. There was an 8 car pile up on 183 and ice was suspected.

There is something falling from the sky right now, it is light and white.

I'm looking at the latest RUC sounding valid at 13Z for Austin. Shows a very shallow sub-freezing level about 2000 ft thick. Above that the temperature rises, up to 48 at 7000 ft and doesn't drop below freezing until 12000-13000 ft. So the only layer below freezing is right at the surface. 2000 feet seems low for snow to form. Could it be frozen drizzle? Unless the RUC soundings are way off....

Actually 57, I believe we have experienced some falling graupel. Scattered reports of "slush balls" according to the media. I didn't see any here at my house but there have been a lot of reports like this.

Meanwhile, it's 29.6 degrees here in north Austin and surface objects are beginning to ice over.

[JenBayles]

Just checked the thermometer in the garage here under the BC Dome: 34 degrees. Down we go...

[wxman57]

In Austin, there have been over 66 wrecks since midnight. That was the last figure I heard. There was an 8 car pile up on 183 and ice was suspected.

There is something falling from the sky right now, it is light and white.

I'm looking at the latest RUC sounding valid at 13Z for Austin. Shows a very shallow sub-freezing level about 2000 ft thick. Above that the temperature rises, up to 48 at 7000 ft and doesn't drop below freezing until 12000-13000 ft. So the only layer below freezing is right at the surface. 2000 feet seems low for snow to form. Could it be frozen drizzle? Unless the RUC soundings are way off....

Actually 57, I believe we have experienced some falling graupel. Scattered reports of "slush balls" according to the media. I didn't see any here at my house but there have been a lot of reports like this.

Meanwhile, it's 29.6 degrees here in north Austin and surface objects are beginning to ice over.

I saw lots of graupel when i worked off the southern tip of Argentina in 1980. It would come down so hard you could barely see 1/4 mile but it made no sound. Like little styrofoam balls falling. Graupel is partially melted snowflakes that re-freezes.

[JonathanBelles]

i have never heard of graupel

[ROCK]

New word for me also Wx57....Argentina? They really get that cold down there. wow