SE TX/SW LA Winter WX - 2011-2012

[attallaman]

Heading out to another parade tonight. This parade is going to be a bit chilly but i'm all bundled up!

Another Mardi Gras parade?

That was Monday, but I think she goes to a lot of them.

Sorry about that, I should have paid attention to her posting date. Please accept my apologies.

[southerngale]

No reason to be sorry... I was just sayin'

[LaBreeze]

latest gfs shows a chance for snow tuesday.. up to an inch.. (or more in some parts)

I'm hearing this also from a local met. Is this in the realm of possibility? Any additional info. on this welcomed and appreciated in advance.

[southerngale]

latest gfs shows a chance for snow tuesday.. up to an inch.. (or more in some parts)

I'm hearing this also from a local met. Is this in the realm of possibility? Any additional info. on this welcomed and appreciated in advance.

Check the Texas thread. There's a lot of discussion in there.

[sphelps8681]

My forecast according to the NWS for Tues night.

Tuesday Night: Rain and snow likely. Mostly cloudy, with a low around 34. North wind between 10 and 15 mph. Chance of precipitation is 60%. It will be 60% chance of rain by Tues.

[southerngale]

My forecast according to the NWS for Tues night.

Tuesday Night: Rain and snow likely. Mostly cloudy, with a low around 34. North wind between 10 and 15 mph. Chance of precipitation is 60%. It will be 60% chance of rain by Tues.

I had the same forecast as you a little while ago. Look again. *poof*

[CajunMama]

A day like today makes me yearn for spring. It's a beautiful 68 out there.

[jinftl]

Spring may not be far off....


AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
335 PM CST SAT FEB 20 2010

.LONG TERM...

THE TROUGH AXIS SHOULD FINALLY BEGIN TO PULL TO THE EAST OVER THE
WEEKEND...AS HIGHLY AMPLIFIED OMEGA PATTERN TAKES SHAPE ACROSS
THE CONUS. ACROSS THE CENTER OF THE NATION...A VERY STRONG UPPER
LEVEL RIDGE WILL SETTLE IN...BRINGING WARMER TEMPERATURES BACK TO
THE AREA FOR THE UPCOMING WEEKEND.

A day like today makes me yearn for spring. It's a beautiful 68 out there.

[crazycajuncane]

Local weekend Met already talking about a chance of wintery precip on Tuesday night into Wednesday morning...

Okay we've gone years without seeing snow and this winter alone we're going on 3 days?

The low is forecast at 37 on Tuesday night... not sure that's cold enough, but he mentioned something in the models... we shall see how the next few days unfold!

[LaBreeze]

Local weekend Met already talking about a chance of wintery precip on Tuesday night into Wednesday morning...

Okay we've gone years without seeing snow and this winter alone we're going on 3 days?

The low is forecast at 37 on Tuesday night... not sure that's cold enough, but he mentioned something in the models... we shall see how the next few days unfold!

Heard the same met crazycajuncane, but I'm thinking we'll be too warm and the sleet may be to our north - possibly CenLa. I guess we'll have to wait and see.

[vbhoutex]

This already in the TX winter thread, but is much more area specific for SW TX:

Here's the "latest" from Houston pro met Jeff Lindner:

Winter Storm heading for TX

Accumulations of snow possible over portions of SE TX Tuesday-Tuesday night.

Significant snow accumulations possible for N of Austin toward Waco (4-8 inches).

Discussion:
Strong cold front heading for SE TX this afternoon...ahead of this boundary temps. have soared into the mid 70's across the region...and it will all end tonight.

Cold front will cross the area overnight with cold air advection in progress on Monday with highs 10-15 degrees colder than today. Next in a new series of upper level storms will arrive into the 4 corners on Monday and head for TX Tuesday while arctic air over the central plains pours southward into the region Monday night.

Upper level storm brings moisture over and into the cold arctic dome starting Tuesday with light band of winter mix starting around mid morning over our NW counties and spreading to other areas of SE TX by Tuesday evening. Dynamics look fairly impressive with this system and some of the short range models are showing decent 700mb instability supportive of meso scale snow banding and burst of heavy snow.

P-type:
Forecast soundings support numerous P-type issues over the region Tuesday/Tuesday night with favorable critical thickness for SN and favorable cold profiles for SN to make it to the surface first up north and then dropping southward. Will break out the following three grid lines for P-type in a first attempt with this event....changes are for sure with this in the coming 24 hours.

N of a line from Columbus to Conroe to Livingston:
Expect a RA/SN/IP mix at the onset of precip with cooling of the air column to below freezing by Tuesday afternoon and change to all SN.

N of a line from Wharton to Downtown Houston to Liberty:
Mostly RA Tuesday then a mix of RA/SN Tuesday evening into Tuesday night...could see a complete change to all SN across Austin, Waller, N Harris, N Liberty Counties.

Coastal Areas:
All RA Tuesday with a possible RA/SN mix late Tuesday night...but mainly RA.

Accumulations:
Surface temperatures with this event will be in the mid to upper 30's based on the GFS sounding data. Dewpoints in the upper 20's to 30 at the start of the precip. do not bode well for evaporative cooling to or below freezing. Feel it is going to be hard to get the surface temp to freezing...which means a lot of melting on contact. On the other hand, meso models are pointing toward banding features over the northern part of the area...which may support heavy snow and rapid accumulations as seen over the DFW area 2 weeks ago even with surface temps. in the 32-35 range.

Needless to say this is a low confidence forecast!

N of a line from Brenham to Coldspring:
Slushy accumulations of 1-2 inches mainly on grassy surfaces.

Columbus to The Woodlands:
A dusting to .5 inch of accumulation.

Little to no accumulation is expect south of this line at this time...most of what falls in this region will melt on contact.

Some significant changes can be expected with accumulations as this event unfolds.

Temperatures may make it to freezing along and N of I-10 by Wednesday morning supporting the freezing of melted snow on bridges and overpasses.

At this time the NWS is holding off on the issuance of Winter Storm products, but they will likely be coming in the next 12 hours or so...especially for areas N of HWY 105.

To say the least the next few days look very interesting for our area!

[crazycajuncane]

Local weekend Met already talking about a chance of wintery precip on Tuesday night into Wednesday morning...

Okay we've gone years without seeing snow and this winter alone we're going on 3 days?

The low is forecast at 37 on Tuesday night... not sure that's cold enough, but he mentioned something in the models... we shall see how the next few days unfold!

Heard the same met crazycajuncane, but I'm thinking we'll be too warm and the sleet may be to our north - possibly CenLa. I guess we'll have to wait and see.

With a low of 37 I don't see it happening myself. Maybe if we get to 34 - 35 will I believe it!

[JenBayles]

Every time I check the NWS forecast it gets worse - or better depending on your perspective. Now we've got an 80% chance of rain turning to snow Tuesday afternoon, and 90% for snow Tuesday night. Why does this always happen when I have an emergency with my my mother?!

[southerngale]

Winter Storm Watch for me and other areas in SE TX and LA. NWS LCH mentions light snow possible all the way to the coast.

Winter Storm Watch

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE LAKE CHARLES LA
208 PM CST MON FEB 22 2010

...LATE SEASON SNOW POSSIBLE OVER CENTRAL LOUISIANA AND LAKES REGION...

.FALLING PRESSURES JUST OFFSHORE BROWNSVILLE WILL INDUCE ANOTHER
GULF LOW BY EARLY MORNING TUESDAY. LARGE DIFFERENCES-IN-PRESSURE...
AND SUBSEQUENT STRONG BLUE NORTHERS...WILL CARRY CANADIAN AIR INTO
THE WESTERN UPPER GULF COAST STATES. AN OVERRUNNING RAIN SCENARIO
WILL BE IN THE WORKS BY MIDAFTERNOON TUESDAY...AS A PASSING
DISTURBANCE ALOFT INITIATES RAIN WHICH FALLS THROUGH THE CANADIAN
AIR. THE CHILLY RAIN WILL TRANSITION TO SNOW BY TUESDAY EVENING.
THE PRECIPITATION WILL BE COMING TO AN END ON WEDNESDAY...AS THE
GULF LOW EXITS INTO THE SOUTHWEST GULF OF MEXICO.

LAZ027>033-TXZ180>182-201-230600-
/O.NEW.KLCH.WS.A.0001.100224T0000Z-100224T1200Z/
VERNON-RAPIDES-AVOYELLES-BEAUREGARD-ALLEN-EVANGELINE-ST. LANDRY-
TYLER-JASPER-NEWTON-HARDIN-
INCLUDING THE CITIES OF...LEESVILLE...ALEXANDRIA...MARKSVILLE...
DERIDDER...OAKDALE...VILLE PLATTE...OPELOUSAS...WOODVILLE...
JASPER...NEWTON...LUMBERTON
208 PM CST MON FEB 22 2010

...WINTER STORM WATCH IN EFFECT FROM TUESDAY EVENING THROUGH LATE
TUESDAY NIGHT...

THE NATIONAL WEATHER SERVICE IN LAKE CHARLES HAS ISSUED A WINTER
STORM WATCH...WHICH IS IN EFFECT FROM TUESDAY EVENING THROUGH
LATE TUESDAY NIGHT.

OVERRUNNING RAIN WILL SPREAD FROM WEST TO EAST ACROSS THE WATCH
AREA BY TUESDAY AFTERNOON. THE CHILLY RAIN WILL TRANSITION TO SNOW
BY TUESDAY EVENING. SNOWFALL AMOUNTS BETWEEN 1 AND 2 INCHES IS
POSSIBLE ACROSS THE PINEY HILLS OF CENTRAL LOUISIANA AND THE
LAKES REGION OF SOUTHEAST TEXAS. LIGHT SNOW MAY REACH ALL THE WAY
TO THE COAST...ESPECIALLY ALONG THE I-10 CORRIDOR BETWEEN
BEAUMONT AND LAKE CHARLES. MOST FROZEN PRECIPITATION WILL BE
COMING TO AN END BY MIDMORNING WEDNESDAY.

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]

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
259 PM CST MON FEB 22 2010

...A WINTER STORM WARNING IS NOW IN EFFECT FOR THE NORTHERN THIRD
OF SOUTHEAST TEXAS...

...A WINTER WEATHER ADVISORY IS IN EFFECT FOR THE CENTRAL PORTIONS
OF SOUTHEAST TEXAS...

.A VIGOROUS UPPER LEVEL DISTURBANCE WILL APPROACH SOUTHEAST TEXAS
ON TUESDAY. THIS SYSTEM WILL BRING A VARIETY OF WINTER WEATHER TO
THE REGION. RAIN WILL DEVELOP TUESDAY MORNING AND QUICKLY CHANGE
OVER TO SNOW. SNOW WILL PERSIST THROUGH TUESDAY EVENING AND END
BETWEEN 11 PM TUESDAY EVENING AND 3 AM WEDNESDAY.

TXZ200-210>213-226-227-230500-
/O.NEW.KHGX.WW.Y.0002.100223T2000Z-100224T1200Z/
AUSTIN-COLORADO-FORT BEND-HARRIS-LIBERTY-WALLER-WHARTON-
INCLUDING THE CITIES OF...BELLVILLE...BROOKSHIRE...CLEVELAND...
COLUMBUS...DAYTON...EAGLE LAKE...EL CAMPO...HEMPSTEAD...HOUSTON...
HUMBLE...KATY...LIBERTY...MISSOURI CITY...PASADENA...PIERCE...
PRAIRIE VIEW...RICHMOND...ROSENBERG...SEALY...SUGAR LAND...
TOMBALL...WEIMAR...WHARTON
259 PM CST MON FEB 22 2010

...WINTER WEATHER ADVISORY IN EFFECT FROM 2 PM TUESDAY TO 6 AM
CST WEDNESDAY...

THE NATIONAL WEATHER SERVICE IN HOUSTON/GALVESTON HAS ISSUED A
WINTER WEATHER ADVISORY FOR A RAIN AND SNOW MIX...WHICH IS IN
EFFECT FROM 2 PM TUESDAY TO 6 AM CST WEDNESDAY.

A VIGOROUS UPPER LEVEL DISTURBANCE WILL APPROACH SOUTHEAST TEXAS
ON TUESDAY. THIS SYSTEM WILL BRING A VARIETY OF WINTER WEATHER TO
THE REGION. RAIN WILL DEVELOP TUESDAY MORNING THEN QUICKLY CHANGE
OVER DURING THE AFTERNOON TO A RAIN SNOW MIX. THIS RAIN SNOW MIX
WILL EXPAND ACROSS THE ADVISORY AREA DURING THE AFTERNOON WITH
MOST AREAS IN THE ADVISORY EXPERIENCING RAIN AND SNOW BEFORE 6 PM.
WITH THE WARM GROUND NO SIGNIFICANT ACCUMULATIONS ARE EXPECTED
DURING THE AFTERNOON...BUT DURING THE EVENING SNOW MAY BEGIN TO
STICK ON GRASSY AREAS AND CAR ROOFS. THE RAIN AND SNOW MIX MAY
CHANGE OVER TO JUST SNOW AFTER MIDNIGHT. ANY ACCUMULATIONS DURING
THE LATE EVENING THROUGH 3 AM TIME FRAME SHOULD RANGE FROM ONE
QUARTER TO ONE AND HALF INCHES AND BE FROM I-10 NORTHWARD. SOME
ELEVATED ROADWAYS AND BRIDGES MAY GET ICY ACROSS THE NORTHERN
PORTIONS OF AUSTIN...WALLER...HARRIS...AND LIBERTY COUNTIES.

THIS IS A DEVELOPING WINTER WEATHER SITUATION AND IF TEMPERATURES
ARE SLIGHTLY COOLER OR SLIGHTLY WARMER THAN FORECAST COULD HAVE
TREMENDOUS IMPLICATIONS ON WHERE SNOW FALLS AND HOW MUCH WILL
ACCUMULATE.

[vbhoutex]

Latest from Jeff Lindner:

Major Winter Storm heading for SE TX

Significant accumulations of snow expected on Tuesday/Tuesday night over the area.

Winter Storm Warning issued for Tuesday: Brazos, Burleson, Madison, Houston, Trinity, Polk, San Jacinto, Grimes, Montgomery, Walker

Winter Weather Advisory issued from 200pm Tuesday to 600am Wednesday: Harris, Austin, Colorado, Fort Bend, Liberty, Waller, Wharton


Discussion:

Overall consensus today has been to push the snowfall and accumulations southward which now brings Harris County more under the threat for accumulations. Models are still hammering away at some fairly hefty banding features over the northern ½ to 1/3 of the area and feel some surprisingly high totals may be had in the area bounded by College Station to Livingston. Will likely also see snow all the way to the coast mixed with the rain Tuesday night.

Will start to see accumulations by mid morning Tuesday up north and then spread southward during the day on Tuesday. Will see rain start to mix and change to snow from NW to SE during the afternoon on Tuesday with many areas having all snow by Tuesday evening. Ground temperatures are warm and some of the snow will melt on impact. Heavy snow bands will help mitigate the warm ground allowing for quick accumulations over our northern counties. Additionally, as surface temperatures fall toward and to freezing Tuesday evening greater accumulation and formation of glazing of area bridges/overpasses appears likely. Would like to see lower dewpoints for IAH on Tuesday to support accumulations, but it looks close enough especially if moderate/heavy snow falls for some quick accumulation even with surface temperatures above freezing…similar to Dec 4, 2009.

Accumulations:

College Station to Livingston northward:

Accumulations of 2-4” with higher amounts (6+” possible).

Columbus to The Woodlands to Humble northward:

Accumulations of 1-3” with isolated amounts to up 4 inches

Katy to downtown Houston to Liberty northward:

Accumulations of .5-1”

Sugar Land to Pearland to High Island northward:

A dusting to ½ inch of accumulation.

South and West of Sugar Land to High Island:

Snow will mix with the rain, but no accumulation is expected

[southerngale]

Latest discussion from NWS LCH. Explains things nicely.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAKE CHARLES LA
318 PM CST MON FEB 22 2010


.DISCUSSION...

FOR TONIGHT...WEAK ADVECTIVE COOLING WILL PREVAIL AS HIGH PRESSURE
BECOMES MORE DISTINCT ACROSS SOUTH TEXAS. THE OVERNIGHT MINIMUMS
WILL BE RUNNING A FEW DEGREES BELOW NORMAL.

BY TUESDAY...THE SOUTH-TEXAS HIGH PRESSURE CELL...LOOSELY CONTAINED
WITHIN THE MORE EXTENSIVE GREAT PLAINS HIGH PRESSURE SYSTEM...
WILL SEPARATE EASTWARD...REACHING THE SOUTHEAST-LOUISIANA COASTAL WATERS
BY EARLY EVENING TUESDAY.

SOUTHERLY WINDS (ITS ASSOCIATED CLOCKWISE CIRCULATION) ALONG THE
WESTERN PERIPHERY OF THE HIGH-PRESSURE CELL WILL CARRY GULF AIR
POLEWARD. THE RETURNING GULF AIR SATURATES UPON UPSLIDING THE
CANADIAN AIR. THE WARM CONVEYOR BELT AIRSTREAM IS SETTING UP.

THE TRAVELING GRAND CANYON SHORTWAVE WILL SIGNIFICANTLY AUGMENT THE
GENTLE LIFT ATTENDING THE WARM CONVEYOR BELT. AN OVERRUNNING RAIN
SCENARIO WILL FOLLOW...WITH CHILLY RAIN FALLING THROUGH THE CANADIAN
AIR MASS.

BY TUESDAY EVENING...THE ONGOING RAIN WILL WET-BULB COOL THE SURFACE
LAYER...INITIATING A TRANSITION OVER TO SNOW. A CRITICAL VARIABLE
EXAMINED IN ASSESSING THE LIKELIHOOD OF SNOW IS THE STRENGTH OF THE
ICE MULTIPLICATION (OR SPLINTERING) PROCESS.

THE SPLINTERING ZONE (A SATURATED LAYER WITH WET BULBS AROUND MINUS
4 DEG C...PLUS/MINUS 3 C DEG) IS BEST REVEALED IN THE SATURATED
850-700 PARTIAL THICKNESS LAYER. MESO-SYNOPTIC LIFT (ATTENDING THE
GRAND-CANYON SHORTWAVE) WILL GREATLY AID IN THE ICE MULTIPLICATION
PROCESS. RISING SUPER-COOLED LIQUID WATER DROPS WILL COLLIDE WITH
RIMING ICE HABITS WHICH FREE FALL THROUGH A SUBFREEZING ATMOSPHERE
...AND SPLINTER. THE NUMBER OF ICE PARTICLES GREATLY INCREASES...ITS
CHANCES OF REACHING THE NEAR FREEZING GROUND INCREASES AS WELL.

THE GFS SUGGESTS THAT THE SNOW MAY REACH ALL THE WAY TO THE COAST.
AT PRESENT...BELIEVE THAT THE SIGNIFICANT SNOWFALL AMOUNTS WILL BE
LIMITED TO THE PINEY HILLS OF CENTRAL LOUISIANA AND THE LAKES REGION
OF SOUTHEAST TEXAS.

HOWEVER...REMAIN UNCERTAIN ABOUT THE SNOW AMOUNTS ALONG AND SOUTH OF
THE I-10 CORRIDOR...ESPECIALLY BETWEEN BEAUMONT AND LAKE CHARLES.

[Ptarmigan]

If it snows tomorrow, it would be the first time in 25 years that a winter saw two >0.005" or Trace (+0.005") snowfall event in Houston. The last time we saw this was in 1985, the winter of 1984-85.

Above Trace Snowfall
1 Snowfall=Every 5 years
2 Snowfall=Every 25 years
3 Snowfall=Every 125 years
4 Snowfall=Every 625 years

[PTrackerLA]

Imagine the frustration we will have next year if we don't have any chances of snow! Between this winter and last winter we are really getting spoiled! The 18z GFS seems to indicate a changeover to all snow for even Lafayette. If it comes down heavy enough we could see light accumulations for a brief period like last week. Can't believe we have a legitimate shot at our 3rd official accumulating snow of the winter!

[shibumi]

If it snows tomorrow, it would be the first time in 25 years that a winter saw two >0.005" or Trace (+0.005") snowfall event in Houston. The last time we saw this was in 1985, the winter of 1984-85.

Above Trace Snowfall
1 Snowfall=Every 5 years
2 Snowfall=Every 25 years
3 Snowfall=Every 125 years
4 Snowfall=Every 625 years

Interesting...though the #4 is not reliable as we have no complete data to make such a conclusion from that long ago!!!