Texas winter wx thread (2009-2010)

[srainhoutx]

Too soon to know. As I have stated, we may not know the 'finer details' other than the Cold Air coming 24-36 hours before hand. I had to refresh my memory a bit today on the December 1989 Arctic Outbreak. The forecast showed the Arctic Air was coming, but the moisture was not mentioned at all until 24 hour prior to that event and then the QPF totals were minimum at best. I suggest we all pay close attention to the NWS and our Pro Mets as we head into the Tuesday/Wednesday time frame.

[cctxhurricanewatcher]

So what is so unique about the Brownsville guys? I mean no disrespect but I am curious as to why the NOAA team down there is so significant when it comes to forecasting arctic outbreaks like this. Being so far south what makes them so special?

What was said above by Mr srainhoutx. The Old Timers and not so much the Newbies that forecast at that office were very good at pointing out Arctic attacks in their early stages. This was way before the multiple models, the modern day GFS, etc. They would go look at the case studies of prior freeze events in the RGV and match it with the current data and put out a pretty accurate forecast.

[msstateguy83]

The following post is NOT an official forecast and should not be used as such. It is just the opinion of the poster and may or may not be backed by sound meteorological data. It is NOT endorsed by any professional institution including storm2k.org. For Official Information please refer to the NHC and NWS products.

good afternoon guys/gals
back in the house here after a break off looking @ the latest data one thing is for sure a MAJOR ARCTIC OUTBREAK
is going to happen this week across the central,southern plains region down into all of tx.. the problem area is
yes the models are showing 'bone dry' pretty much HOWEVER keep in mind the gfs DOES tend to over do precip
as lubbock forecast office stated BUT and a BIG BUT is that in the winter time the models also tend to under
estimate the amount of moisture on hand. so iam not even gonna draw up any forecast at this point b/c quite
frankly its pointless main problem rightnow is temps for highs in the mid to upper teens to low to mid 20s across
northern tx with lows in the single digits for midweek on.. just if you are anywhere in tx as we go into this
week stay close in tuned with your local weather tv or radio to get the very latest as this could go either way
as we head further into this week.

Edit=Disclaimer added by cycloneye.

[cctxhurricanewatcher]

The Brownsville and Corpus AFD's are VERY INTERESTING!

Corpus

LONG TERM (WEDNESDAY THROUGH MONDAY)...EXTENDED PERIOD BEGINS WITH
A WEAK STATIONARY FRONT JUST NORTH OF US. MOISTURE POOLING AND WEAK
ISENTROPIC LIFT SHOULD BE ENOUGH FOR LIGHT DRIZZLE AND SCATTERED
LIGHT RAIN...ESPECIALLY EAST WHERE MOIST FLOW WILL BE A BIT DEEPER.

A MAJOR ARCTIC FRONT IS EXPECTED THROUGH THE AREA LATE WEDNESDAY AND
EARLY THURSDAY. MODEL TIMING IS STILL FLUCTUATING A BIT...BUT
CURRENT THINKING IS FOR THE FRONT TO PUSH THROUGH NORTHERN AREAS
DURING THE OVERNIGHT HOURS...WITH THE FRONT CLEARING THE COAST BY
MIDMORNING AND THE NEARSHORE WATERS BY NOON.

MOISTURE REMAINS LIMITED WITH THIS SYSTEM...SO QPFS WILL BE VERY
LIMITED AS THE FRONT PASSES. BEST CHANCE FOR PRECIPITATION WILL BE
OFFSHORE AND ACROSS THE NORTHEAST. MOST ACTIVITY WILL BE ALONG AND
AHEAD OF THE FRONT...THOUGH THE DYNAMICS ASSOCIATED WITH THE FRONT
MAY BE ABLE TO SQUEEZE OUT SOME BRIEF POST-FRONTAL PRECIP. THIS
PRESENTS A FORECAST CHALLENGE...AS IT IS POSSIBLE THAT COLD AIR
SURGES IN FAST ENOUGH TO CREATE A PARTIAL MIX OF RAIN AND SLEET
BEFORE PRECIP SHUTS OFF ENTIRELY. MODEL FORECAST OUTPUT SUGGESTS
THIS POSSIBILITY UNTIL ABOUT NOON ON THURSDAY...SO EVEN IF IT DOES
OCCUR IT IS UNLIKELY TO HAPPEN LONG ENOUGH TO CREATE A TRAVEL
HAZARD.

MORNING HIGH TEMPERATURES ON THURSDAY WILL FALL THROUGH THE DAY INTO
THE MID 30S OVER MUCH OF THE AREA BY THURSDAY EVENING.

NOTICEABLE SURFACE PRESSURE RISES WILL CREATE WINDY CONDITIONS
THURSDAY...ENHANCED OVER MARINE AREAS AS GUSTS TO GALE FORCE ARE
LIKELY.

ATTENTION THEN SHIFTS TO FREEZES FRIDAY THROUGH SUNDAY MORNINGS. A
HARD FREEZE IS FORECASTED ACROSS INLAND COUNTIES FRIDAY MORNING.
WINDS STAY UP ALONG THE COAST THURSDAY NIGHT SO LOCATIONS ALONG THE
COAST IN THE SOUTHERN COASTAL BEND MAY NOT SEE A FREEZE FRIDAY
MORNING. SHIELD OF AC MOVING ACROSS THE AREA FRIDAY AND CONTINUED
COLD AIR ADVECTION WILL KEEP HIGHS FRIDAY WELL BELOW NORMAL...AND
BELOW GUIDANCE. CLEARING AND LIGHT WINDS SHOULD ALLOW LOCATIONS
CLOSER TO THE COAST TO FREEZE SATURDAY MORNING...WITH ANOTHER HARD
FREEZE INLAND. SUNDAY MORNING MAY PRESENT ANOTHER OPPORTUNITY FOR A
FREEZE BASED ON 10/12Z GFS SURFACE HIGH POSITION.

RETURN FLOW RESUMES ON SUNDAY...WITH MILDER TEMPERATURES AND CHANCES
FOR LIGHT DRIZZLE OR RAIN IN ISENTROPIC LIFT BEGINNING SOON
THEREAFTER.

Brownsville

THURSDAY NIGHT THROUGH SATURDAY: THE SOMEWHAT MODIFIED ARCTIC AIR
MASS SETTLES IN...AND EXPECT A 36 TO 42 HOUR PERIOD WHERE
TEMPERATURES WILL PROBABLY NOT BREAK OUT OF THE 30S. THE BIG
THREATS WILL BE CRITICAL WIND CHILL...ESPECIALLY TOWARD THE COAST
WHERE SPEEDS WILL HOLD SOLIDLY NEAR 20 MPH THROUGH THE NIGHT. BY
FRIDAY MORNING...WE`RE FORECASTING CHILLS FROM THE UPPER TEENS
NORTH TO THE MID 20S SOUTH...SOLIDLY IN ADVISORY COLUMN BUT CLOSE
FOR WARNING (20 VALLEY AND 15 NORTH). AS FOR THE
FREEZE...TEMPERATURES WILL DROP TO OR JUST ABOVE FREEZING NEAR THE
COAST OF CAMERON COUNTY...UPPER 20S TO LOWER 30S ELSEWHERE AND
WE`RE HEDGING IN THE MID TO UPPER 20S (WELL MIXED AND A HARD
FREEZE) WEST AND NORTH. CRASHING DEWPOINTS WILL MAKE LIFE HARD ON
TENDER PLANTS AND CITRUS.

FRIDAY GETS INTERESTING. BOTH THE GFS AND ECMWF ARE TRENDING
TOWARD A WAVE OF MOISTURE EXTENDING FROM THE LOWER VALLEY INTO THE
GULF...SUPPORTED BY A ROBUST 250 MB JET CORE AND RIGHT ENTRANCE
REGION SMACK DAB OVER THE MORE POPULOUS LOCATIONS EXTENDING SOUTH
INTO NORTHEAST MEXICO. MODEL SOUNDINGS INDICATE A WINTRY MIX AT
THE VERY LEAST...FREEZING RAIN WEST OF HIGHWAY 77. FOR NOW...HAVE
INTRODUCED THE MIX WITH A SLIGHT CHANCE/CHANCE SPLIT FROM WEST TO
EAST (LIKELY IN THE OFFSHORE GULF LEGS). FOR NOW WE`RE NOT
EXPECTING A SIGNIFICANT WINTER EVENT...HENCE THE LOW POPS...BUT
THE TRENDS ARE POINTING TOWARDS SOMETHING AND WE`LL CONTINUE TO
UPDATE AS THINGS BECOME MORE CLEAR.

NEEDLESS TO SAY...GUIDANCE TEMPERATURES NOT ONLY CAN`T HANDLE THE
OUTLIER AIR MASS BUT KEEP READINGS TOO HIGH GIVEN THE THICK HIGH
CLOUDS EVERYWHERE AND NOW THE LOW OVERCAST TOWARD THE COAST. PAST
SIMILAR SENSIBLE WEATHER EVENTS...JANUARY 14 1997 AND CHRISTMAS
EVE 2004...EACH HAD DAYTIME HIGHS IN THE LOWER TO MID 30S AND SEE
NO REASON WHY THIS WON`T HAPPEN IN THIS CASE.

FRIDAY NIGHT WILL SEE CLEARING WITH DIMINISHING WINDS BUT STILL
ENOUGH MIXING TO HOLD TEMPERATURES UP A HAIR OUT WEST.
STILL...PLENTY OF COLD AIR DRAINING AND CIRRUS EXITING STAGE RIGHT
EXPECT A SOLID HARD FREEZE FROM HIDALGO TO KENEDY AND POINTS WEST
AS DEWPOINTS CRASH OR REMAIN BELOW 10. LOOKS LIKE A FREEZE TO JUST
NEAR THE COAST AS WELL BUT WITH CLOUDS HOLDING ON LONGEST
LOCATIONS SUCH AS BROWNSVILLE AND PORT ISABEL MAY ONLY DROP TO 30
OR SO...HARLINGEN A FEW DEGREES COLDER.

SATURDAY WILL SEE PLENTY OF SUNSHINE BUT ALSO A LOT OF COLD DRY
AIR REMAINING. GOING FORECAST OF TEMPERATURES REBOUNDING INTO THE
40S LOOKS ON TARGET...AND WILL SET UP THE FROSTY FREEZE TO COME
SATURDAY NIGHT AND SUNDAY MORNING.

REGARDING THIS FREEZE...CLEAR SKIES AND CALM WINDS WITH THE LAST
OF THE COLD SURFACE HIGH SETTLING IN WILL ENSURE TEMPERATURE IN
SHELTERED LOCATIONS PLUMMET BELOW 25...PERHAPS REACHING 20...WITH
8 TO 10 HOURS OF SUBFREEZING TEMPERATURES AS READINGS DROP SHARPLY
AFTER SUNSET.

NO SIGNIFICANT CHANGES SUNDAY THROUGH MONDAY EXCEPT TO ADD MORE
CLOUDS AND SLIGHT CHANCE OF RAIN ON MONDAY IN RETURN FLOW...PSEUDO
WARM FRONTAL SITUATION.

[Snowman67]

Interesting discussion from the Brownsville NWS office this afternoon.

http://forecast.weather.gov/product.php ... glossary=1

[HockeyTx82]

So what is so unique about the Brownsville guys? I mean no disrespect but I am curious as to why the NOAA team down there is so significant when it comes to forecasting arctic outbreaks like this. Being so far south what makes them so special?

What was said above by Mr srainhoutx. The Old Timers and not so much the Newbies that forecast at that office were very good at pointing out Arctic attacks in their early stages. This was way before the multiple models, the modern day GFS, etc. They would go look at the case studies of prior freeze events in the RGV and match it with the current data and put out a pretty accurate forecast.

Interesting that guys so far south would get a good handle on this stuff. Who has the more aged NOAA team in Texas now, perhaps with some of the oldtimers........

[Ntxw]

What's that in northern California 18z nam

[cctxhurricanewatcher]

So what is so unique about the Brownsville guys? I mean no disrespect but I am curious as to why the NOAA team down there is so significant when it comes to forecasting arctic outbreaks like this. Being so far south what makes them so special?

What was said above by Mr srainhoutx. The Old Timers and not so much the Newbies that forecast at that office were very good at pointing out Arctic attacks in their early stages. This was way before the multiple models, the modern day GFS, etc. They would go look at the case studies of prior freeze events in the RGV and match it with the current data and put out a pretty accurate forecast.

Interesting that guys so far south would get a good handle on this stuff. Who has the more aged NOAA team in Texas now, perhaps with some of the oldtimers........

They were good because Agriculture drove the Valley economy back then and we didn't have all the private forecasting services and if they were availabl, they were cost prohibitive for some of the family farms down there. Much of those guys started and retired at that office, so they had a vested interest in the area.

I will say the recent discussions had a touch of old timer lingual.

[srainhoutx]

HGX thoughts...

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
306 PM CST MON JAN 4 2010

...POTENTIALLY RECORD BREAKING COLD EVENT COMING THURSDAY NIGHT THROUGH
SUNDAY MORNING...

.DISCUSSION...
SKIES HAVE CLEARED OUT OF SOUTHEAST TEXAS THIS AFTERNOON...AND THIS
WILL SET THE STAGE FOR A VERY COLD NIGHT AREA WIDE WITH LOW TEMPERATURES
BELOW FREEZING ALL AREAS EXCEPT ALONG THE IMMEDIATE COAST AS SURFACE
HIGH PRESSURE RIDGES INTO THE AREA FROM THE NORTH. LOWS ACROSS PORTIONS
OF OUR NORTH AND NORTHEAST COUNTIES HAVE THE POTENTIAL TO FALL UNDER
25 DEGREES FOR TWO HOURS OR MORE...SO A HARD FREEZE WARNING IS GOING
TO BE ISSUED FOR TONIGHT AND TOMORROW MORNING FROM MIDNIGHT TO 9 AM
FOR LOCATIONS GENERALLY ALONG AND NORTH OF A LINE FROM AROUND ANDERSON
IN GRIMES COUNTY TO CONROE TO CLEVELAND. A SLIGHT WARM UP IS EXPECTED
ON TUESDAY AS THE SURFACE HIGH BEGINS TO EDGE OFF TO THE EAST...AND
THIS WILL KEEP TEMPERATURES FROM FALLING BELOW FREEZING FOR ALL BUT
THE NORTHEAST ON TUESDAY NIGHT. WEDNESDAY WILL BE EVEN WARMER AS A RETURN
FLOW OFF THE GULF BECOMES ESTABLISHED AND STRENGTHENS IN ADVANCE OF
THE NEXT COLD FRONT. BEFORE THE ARRIVAL OF THIS ARCTIC FRONT VERY LATE
WEDNESDAY NIGHT OR EARLY THURSDAY MORNING...MOISTURE LEVELS SHOULD GET
HIGH ENOUGH TO GENERATE SOME SHOWERS MAINLY FROM WEDNESDAY AFTERNOON
THROUGH THE NIGHTTIME HOURS. STICKING WITH THE SLIGHTLY FASTER GFS FRONTAL
TIMING BRINGS THE ARCTIC FRONT TO THE COAST AROUND SUNRISE THURSDAY
MORNING. THE HIGHS FOR THE DAY WILL OCCUR IN THE MORNING AS A MUCH COLDER
AIR MASS BEGINS TO SETTLE INTO SOUTHEAST TEXAS BEHIND THE FRONT. THERE
IS STILL A CHANCE TO SEE SOME MIXED PRECIPITATION AS THE COLDER AIR
MASS MOVES ON IN...BUT MOST OF THE AREA SHOULD DRY OUT BEFORE BELOW
FREEZING TEMPERATURES SETTLE INTO THE AREA. ONCE READINGS DO FALL BELOW
FREEZING THURSDAY AFTERNOON UP NORTH AND LATE THURSDAY EVENING NEAR
THE COAST...THERE IS THE POTENTIAL FOR ROUGHLY THE NORTHERN THIRD OF
THE AREA (NEAR AND NORTH OF A LINE FROM BRENHAM TO THE WOODLANDS TO
THE MOSS HILL AREA) TO REMAIN BELOW FREEZING UNTIL SATURDAY AFTERNOON.
LOCATIONS SOUTH OF THIS AREA ALL THE WAY DOWN TO THE COAST ARE EXPECTED
TO EXPERIENCE A LOT OF LATE NIGHT AND EARLY MORNING HOURS BELOW FREEZING.
ALL SOUTHEAST TEXAS RESIDENTS ARE URGED TO PREPARE FOR THIS POTENTIALLY
RECORD BREAKING COLD EVENT...AND A HARD FREEZE WATCH MIGHT BE ISSUED
ON TUESDAY IN ADVANCE OF THE COLD OUTBREAK. SLIGHTLY WARMER TEMPERATURES
ARE ANTICIPATED AFTER SUNDAY MORNING AS THE ARCTIC SURFACE HIGH EDGES
OFF TO THE EAST. A GRADUAL WARM UP IS STILL ANTICIPATED EARLY NEXT
WEEK...FOLLOWED BY ANOTHER PRETTY HEFTY COLD FRONT AROUND LATE TUESDAY
OR EARLY WEDNESDAY. 42

[Portastorm]

NWSFO San Angelo has some interesting thoughts.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN ANGELO TX
318 PM CST MON JAN 4 2010

.SHORT TERM...
LOW CLOUDS RAPIDLY DISSIPATING THIS AFTERNOON. MID LEVEL CLOUDS IN
THE BIG COUNTRY DID NOT HAVE AS MUCH AFFECT ON LOW STRATUS AS IN
EARLIER THINKING. NAM BFR INDICATES LOW CLOUDS REDEVELOPING IN SW
ZONES...WITH SE UPSLOPE FLOW OVER THE N EDWARDS PLATEAU...AND
COULD SEE SOME ADVECT NORTH INTO THE CONCHO VALLEY. BUT OTHERWISE
LOOKING AT CLEAR SKIES. WITH MOST AREAS SEEING GOOD RADIATIONAL
COOLING CONDITIONS...WENT WITH OVERNIGHT LOWS IN THE LOWER/MID
20S. NICE WARM UP TUESDAY INTO LOWER 50S WITH SOUTH WINDS.

04

.LONG TERM...
THE MAIN CHALLENGES OF THE CURRENT FORECAST ARE HOW COLD
TEMPERATURES WILL GET ON THURSDAY AND FRIDAY...AND HOW LONG
TEMPERATURES WILL STAY BELOW FREEZING. ALSO THERE IS A SLIGHT CHANCE
FOR FREEZING DRIZZLE/SNOW FLURRIES...CURRENTLY PRECIPITATION AMOUNTS
WILL BE LIGHT BUT IT DOES NOT TAKE MUCH FOR ROADWAYS TO BECOME
SLICK. THE DETAILS WILL BE DISCUSSED BELOW.

ON WEDNESDAY...AN UPPER LEVEL LOW OVER SOUTH CENTRAL CANADA WILL DIG
SOUTH THROUGH THE CENTRAL PLAINS BRINGING AN ASSOCIATED ARCTIC AIR
MASS ACROSS TEXAS. MODEL TIMING OF THE ARCTIC COLD FRONT HAS BEEN
CONSISTENT WITH BRINGING THE FRONT THROUGH WEST CENTRAL TEXAS
WEDNESDAY NIGHT INTO THURSDAY MORNING. GFSBUFR 12Z SOUNDING BRINGS
THE FRONT THROUGH THE I-20 CORRIDOR BY 9 PM AND THEN THROUGH THE
I-10 CORRIDOR BY 3 AM. SUSTAINED WINDS BEHIND THE FRONT WILL BE 20
TO 30 MPH THROUGH SUNSET. AS FOR PRECIPITATION...BOTH ECMWF AND GFS
MODELS KEEP THE HEAVIEST MOISTURE TO OUR NORTH AND EAST.
HOWEVER...LIGHT FREEZING DRIZZLE/SNOW WITH THE LIFT JUST BEHIND THE
FRONT IS POSSIBLE AND CONDITIONS MAY NEED TO BE UPDATED IF THE UPPER
LEVEL SYSTEM BRINGS MORE ENERGY THAN EXPECTED ACROSS OUR REGION.

WITH THE SECONDARY WAVE OF ENERGY ROTATING AROUND ON FRIDAY...THERE
MAY BE A CHANCE FOR LIGHT SNOW AS GFSBUFR SOUNDING TEMPERATURES ARE
WELL BELOW FREEZING ACROSS WEST CENTRAL TEXAS. WILL NOT INCLUDE
IN THE WEATHER GRIDS AT THIS TIME DUE TO THE UNCERTAINTY.
TEMPERATURES ARE EXPECTED TO REMAIN AT OR BELOW FREEZING THROUGH
LATE SATURDAY MORNING AS THE WAVE FORCES THE ARCTIC AIR SOUTH INTO
OUR AREA. HAVE TAPERED TEMPERATURES DOWN WITH THE COLDEST DAY
EXPECTED ON FRIDAY.

FOR THE WEEKEND...AN UPPER LEVEL RIDGE BUILDS INTO THE WESTERN CONUS
RETURNING NORTHWEST FLOW ALOFT. SKIES WILL START TO CLEAR...HOWEVER
TEMPERATURES WILL BE SLOW TO REBOUND AS THE ARCTIC AIR MASS SLOWLY
EDGES EASTWARD.

[jasons2k]

It looks like the 'real deal' is here this time. Looks like a lot of dead queen palms, etc., are on tap for the Houston area after this one.

Trying to figure out just how extensive my cold preperations will be....I just don't have a whole day to spend in the yard wrapping stuff up. OTOH it will be very costly to replace everything I could lose in this one (4 majesty palms, 2 pygmy dates, 1 orange tree, 3 hawaiian tis, 2 bird of paradise).

This will probaby kill-off what's left of my Florida Gardenia and any Hibiscus too.

Everything else is either dead already from the last freeze or hardy enough that I don't need to worry (I think my fan palms, sagos, & windmill palms should be OK).

I have some ligustrums too - I know they are subtropical but I have not idea what they are hardy down to (I think 20-ish)...they are all over Houston though.

[srainhoutx]

It looks like the 'real deal' is here this time. Looks like a lot of dead queen palms, etc., are on tap for the Houston area after this one.

Trying to figure out just how extensive my cold preperations will be....I just don't have a whole day to spend in the yard wrapping stuff up. OTOH it will be very costly to replace everything I could lose in this one (4 majesty palms, 2 pygmy dates, 1 orange tree, 3 hawaiian tis, 2 bird of paradise).

This will probaby kill-off what's left of my Florida Gardenia and any Hibiscus too.

Everything else is either dead already from the last freeze or hardy enough that I don't need to worry (I think my fan palms, sagos, & windmill palms should be OK).

I have some ligustrums too - I know they are subtropical but I have not idea what they are hardy down to (I think 20-ish)...they are all over Houston though.

I know Jason. I have to cover my pygmy date that is not so pygmy (14ft). The pool and fish pond (heater is running and will cover w/2 newborn baby koi) will be ready. My hass avocado is toast. ~sigh~ We harvested close to a 1000 tangerines yesterday from a neighbor 20 ft tree as well.

[gboudx]

I have some ligustrums too - I know they are subtropical but I have not idea what they are hardy down to (I think 20-ish)...they are all over Houston though.

I have ligustrums. I know we've hit the upper-teens since I've had them. And freezing rain has covered them, and snow. I've never covered them and they've always started spring growth with no issues. I'm not covering them now.

[Portastorm]

NWS New Braunfels at least mentions the Canadian! See below:

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
351 PM CST MON JAN 4 2010

.DISCUSSION...
WEAK ISENTROPIC LIFT WILL KEEP CLOUDS BANKED UP AGAINST THE
SERRIANAS DEL BURROS TONIGHT INTO TUESDAY, DRIFTING ACROSS THE
RIO GRANDE AT TIMES, ESPECIALLY ON TUESDAY. OTHERWISE, HIGH
PRESSURE WILL PERSIST INTO TUESDAY. LIGHT WINDS, CLEAR SKIES, AND
LOW DEWPOINTS WILL SET THE STAGE FOR A HARD FREEZE TONIGHT.
SURFACE HIGH MOVES OFF TO THE EAST LATE TUESDAY WITH SOUTHERLY
WINDS RETURNING LEADING TO A WARMING TREND GOING INTO WEDNESDAY.
PATCHY DRIZZLE AND LIGHT RAIN ARE POSSIBLE ACROSS EASTERN AREAS
WEDNESDAY INTO WEDNESDAY NIGHT. AN ARCTIC COLD FRONT WILL MOVE
ACROSS THE AREA LATE WEDNESDAY NIGHT INTO EARLY THURSDAY MORNING.
THE FRONTAL SURFACE IS STEEP AND MOISTURE WILL RAPIDLY DECREASE
WITH ITS PASSAGE, HOWEVER FORECAST SOUNDINGS SUGGEST A BRIEF
WINDOW FOR SLEET THURSDAY MORNING ACROSS SOUTHEASTERN AREAS WHERE
MOISTURE WILL LINGER THE LONGEST. STRONG COLD ADVECTION WILL LEAD
TO BREEZY TO WINDY CONDITIONS THURSDAY INTO THURSDAY NIGHT AS THE
ARCTIC SURFACE HIGH BUILDS INTO THE AREA. DEWPOINTS WILL FALL INTO
THE SINGLE DIGITS AND TEENS. EXPECT LOWS IN THE TEENS ACROSS THE
HILL COUNTRY AND UPPER TEENS TO LOWER 20S ACROSS SOUTH CENTRAL
TEXAS FRIDAY MORNING AND SATURDAY MORNING. THESE READINGS WILL BE
NEAR OR BELOW THE RECORDS FOR THOSE DAYS FOR MOST OF THE CLIMATE
SITES. SEE THE CLIMATE SECTION BELOW. THE ARCTIC AIRMASS WILL
PERSIST GOING INTO THE WEEKEND. OF INTEREST IS AN UPPER LEVEL
SHORT-WAVE THAT MOVES ACROSS THE AREA ON FRIDAY. THE CANADIAN
MODEL SUGGESTS ENOUGH MOISTURE FOR LIGHT SNOW, HOWEVER ALL OTHER
MODELS ARE DRY WITH ONLY FLURRIES AT MOST. FOR NOW WILL GO WITH
SILENT 10S FOR POPS. THE ARCTIC AIRMASS MOVES OFF TO THE EAST ON
MONDAY AND WARM ADVECTION AND ISENTROPIC LIFT MAY GENERATE SOME
RAIN ON MONDAY.

[southerngale]

This is a little OT as it's from the Birmingham office, but it's hilarious. You don't see many AFD's like this.

This is from the overnight AFD. Be sure to read the whole thing.

.DISCUSSION...

BACK WHEN I MOVED TO ALABAMA IN JANUARY OF 1990...I FREQUENTLY
HEARD PEOPLE REFER TO HOW COLD IT GOT AROUND CHRISTMAS TIME A
MONTH EARLIER. AND THE WAY IT WAS DESCRIBED TO ME WAS THAT IT
WASN`T AN ALL-OF-A-SUDDEN ARCTIC BLAST THAT CAME IN. IT WAS MORE
LIKE A GRADUAL CHILL DOWN...A FEW DEGREES A DAY...BEFORE YOU KNEW
IT IT WAS DOWN INTO THE SINGLE DIGITS. THAT`S A LOT LIKE HOW
THINGS HAVE BEEN HERE LATELY...AND WILL CONTINUE TO BE THROUGH
MUCH OF THIS WEEK. CONDITIONS THIS MORNING ARE INDEED COLD...BUT
IT DOES APPEAR WE WILL BE GETTING EVEN COLDER.

THERE ARE ALSO A FEW LIGHT ECHOES ON THE RADAR SCOPE TO OUR
NORTHWEST...WITH SNOW FLURRIES BEING REPORTED AS CLOSE AS
GREENVILLE MS AND MEMPHIS. THAT SNOW APPEARS TO BE ASSOCIATED WITH
A SHORTWAVE TROUGH ROUNDING THE BASE OF THE BIG UPPER TROUGH
ACROSS THE EASTERN STATES. MODELS DO DRY UP THE PRECIP AS IT TRIES
TO PUSH INTO THE SINGLE DIGIT DEWPOINTS HERE IN ALABAMA. I TOYED
WITH THE IDEA OF ADDING SOME FLURRIES INTO THE FORECAST TODAY FOR
THE WEST CENTRAL AND SOUTHWESTERN COUNTIES...BUT DECIDED AGAINST
IT BASED ON THE DRYNESS OF THE SURFACE AIR MASS.

COLD ADVECTION CONTINUES TONIGHT...AND MORE COLD HIGH PRESSURE
SETTLES IN. HARD FREEZE SHOULD EASILY BE EVEN MORE WIDESPREAD
TONIGHT THAN THIS MORNING...AND AS SOON AS CURRENT HARD FREEZE
WARNING EXPIRES WE WILL PROBABLY NEED TO UPGRADE THE WATCH TONIGHT
TO A WARNING. BUT AS THE SHAM-WOW GUY WOULD SAY..."BUT WAIT
THERE`S MORE."

AS IF DEALING WITH THE COLD WASN`T BAD ENOUGH WE STILL HAVE TO
CONTEND WITH THE POSSIBILITY OF WINTRY PRECIP ON THURSDAY...AS
ANOTHER SHORTWAVE ROUNDS THE BASE OF THE LONGWAVE TROUGH. BUT THE
04/0000Z MODEL RUNS PAINT A LESS CERTAIN FORECAST THAN APPARENTLY
THE PREVIOUS RUNS DID. I DID CONTINUE THE HIGH POPS FOR THURSDAY
AND THURSDAY NIGHT...AS I DO THINK THERE IS A GOOD
CHANCE/LIKELIHOOD OF MOST SPOTS GETTING AT LEAST 0.01 OF LIQUID
EQUIVALENT. BUT THEN AGAIN... I DON`T FORESEE A LOT OF PLACES
GETTING ANY MORE THAN 0.10 EITHER. SO ITS NOT QUITE TIME TO GET
TOO EXCITED ABOUT A MAJOR SNOWFALL. PLUS...THERE IS AGAIN SOME
QUESTION AND UNCERTAINTY REGARDING PRECIP TYPE IN THE SOUTHERN
PORTION OF THE FORECAST AREA.

AND QUITE FRANKLY...I THINK THE MAIN STORY WE NEED TO BE SELLING
FOR THE END OF THE WEEK IS THAT OF THE COLD (WHICH COULD
POTENTIALLY BE DEADLY) RATHER THAN THE SNOW POTENTIAL (WHICH
LOOKS MORE LIKE AN INCONVENIENCE IN COMPARISON). ALL SIGNS POINT
TO SINGLE DIGIT LOW TEMPERATURES BY SATURDAY AND SUNDAY MORNINGS FOR
MUCH OF THE OUTLYING AREAS...AND 10 TO 15 DEGREES IN THE CITIES.
ONCE SOME AREAS GO BELOW FREEZING THURSDAY AFTERNOON OR EVENING...
THEY MAY NOT CLIMB BACK ABOVE FREEZING UNTIL SUNDAY AFTERNOON.

AND IF YOU ORDER NOW (BECAUSE WE CAN`T DO THIS ALL DAY)...WE`LL
INCLUDE ANOTHER POTENTIAL WINTER WEATHER THREAT EARLY TO MIDDLE
NEXT WEEK.

[rhoby13]

From Bob Rose, LCRA.

Outbreak of Arctic Air Expcted Wednesday Night into Thursday - Mon. 1/4/2010
The following is a message I shared with folks within LCRA about the upcoming outbreak of arctic air:

I hope everyone had a very Happy New Year. I wanted to pass along an update on the arctic air that will be spreading south across our region later this week. A large mass of arctic air currently located over northern Alaska and northwestern Canada is beginning to sink southeast and will reach Central Texas Wednesday night. Make no mistake, this will be some very cold air, likely the coldest air our region has seen in several years. Folks should begin preparation now for an extended period of very cold temperatures that will last between Thursday and Sunday mornings. This extended period of bitter cold will bring the potential for freezing pipes while stressing livestock and outside animals.

This morning's weather maps showed a ridge of high pressure in the upper atmosphere building north along the West Coast into Alaska. Downstream of the ridge, a deep trough of low pressure is in place across eastern Canada and the eastern US. This "ridge/trough" pattern is currently allowing cold arctic air to spill south out of Canada and into the southern US. But a bitterly cold arctic air mass is currently moving east across northern Alaska and northwestern Canada where the temperature is between 20 and 40 degrees below zero. The current "ridge/trough" Jet Stream configuration will allow this cold air to sink south through the central US over the next 3 to 4 days. With a healthy snow pack in place across the Plains states, this arctic air won't warm all that much by the time it reaches Texas. The latest forecast data indicates the leading edge of this arctic air mass will reach the Red River Valley sometime late Wednesday afternoon/Wednesday evening, with the cold front sinking south across our region Wednesday night.

Temperatures are forecast to fall to or just below freezing across most of the Hill Country and Central Texas by Thursday morning . Lows are forecast to be in the upper 30s towards the coast. Moisture convergence along and just behind the cold front does look to cause the development of some light precipitation. Most of the Hill Country and Central Texas regions could see a mixture of freezing rain, freezing drizzle and sleet beginning late Wednesday night, continuing into Thursday morning. As of now, significant accumulations are not expected as the opportunity for precipitation will only last a few hours. Towards the coast, a mixture of rain and occasional sleet is forecast Thursday morning into early afternoon. The threat for precipitation should end from west to east Thursday morning into the afternoon. Clouds are forecast to decrease and the sky should become partly Thursday afternoon into Thursday evening.

Thursday's weather will be windy and cold. Temperatures will hold in the low 30s across the northern counties of the Hill Country and Central Texas with low to middle 30s across the Austin area and upper 30s to around 40 degrees towards the coast. Lows Friday morning are forecast to reach the low and middle teens across the Hill Country, the upper teens to around 20 degrees across the Austin and Central Texas area and near 20 degrees towards the coast. Friday's weather will mostly sunny but quite cold as the arctic high pressure system begins moving south over Texas. High temperatures will include the upper 20s across the northern counties with low to mid 30s across the rest of the region.

Friday night's temperatures are looking to be the coldest of the week as the wind goes calm. Lows could reach the upper single digits to about 10 degrees across the Hill Country, the upper teens across Central Texas and near 20 degrees towards the coast. Saturday's weather will be sunny but continued very cold with highs in the middle to upper 30s. Lows Sunday morning will again be quite cold, ranging from the middle teens across the Hill Country to the middle 20s towards the coast. Sunday's weather is shaping up to be sunny but a little warmer with highs in the middle to upper 40s.

This particular arctic air mass is forecast to move east of our region late next Sunday into next Monday with somewhat milder temperatures developing next Monday and Tuesday. However, there are signs that more cold arctic air will spill south through the middle of the country around the middle of next week.

I'll pass along additional updates on this arctic outbreak over the next couple of days. Feel free to contact me with any questions or concerns.

Regards,

Bob

[Texas Snowman]

The following post is NOT an official forecast and should not be used as such. It is just the opinion of the poster and may or may not be backed by sound meteorological data. It is NOT endorsed by any professional institution including storm2k.org. For Official Information please refer to the NHC and NWS products.

good afternoon guys/gals
back in the house here after a break off looking @ the latest data one thing is for sure a MAJOR ARCTIC OUTBREAK
is going to happen this week across the central,southern plains region down into all of tx.. the problem area is
yes the models are showing 'bone dry' pretty much HOWEVER keep in mind the gfs DOES tend to over do precip
as lubbock forecast office stated BUT and a BIG BUT is that in the winter time the models also tend to under
estimate the amount of moisture on hand. so iam not even gonna draw up any forecast at this point b/c quite
frankly its pointless main problem rightnow is temps for highs in the mid to upper teens to low to mid 20s across
northern tx with lows in the single digits for midweek on.. just if you are anywhere in tx as we go into this
week stay close in tuned with your local weather tv or radio to get the very latest as this could go either way
as we head further into this week.

Edit=Disclaimer added by cycloneye.

While I hope there is a little snow surprise, I think the biggest issue will be the temps.

FW NWS has cut forecasted temps significantly over the last day or so. High here in Grayson County on Thursday is progged to be 21 and 21 again on Friday with lows near 11 degrees both days.

If memory serves correct, it seems like the cold air intrusions recently have been a few degrees colder than the models initially advertised.

Wouldn't be surprised to see high temps in the upper teens one of those days and lows in the single digits.

[wxman57]

:uarrow: Too soon to know. As I have stated, we may not know the 'finer details' other than the Cold Air coming 24-36 hours before hand. I had to refresh my memory a bit today on the December 1989 Arctic Outbreak. The forecast showed the Arctic Air was coming, but the moisture was not mentioned at all until 24 hour prior to that event and then the QPF totals were minimum at best. I suggest we all pay close attention to the NWS and our Pro Mets as we head into the Tuesday/Wednesday time frame.

I don't remember the 1989 event too well (was working aviation weather back then), but I do know that the models in 1989 were nothing like what we have now. The long range MRF went out to 120 hrs in 24 hour increments, I believe. No GFS 3 hr forecasts out to 180 hrs then 6 hr forecasts out to 384 hrs.

There is still nothing to indicate any post-frontal disturbance to produce any precip, except for the Canadian which remains all on its own with such a solution.

Here's an 18Z GFS raw data plot I just made for IAH:

[iorange55]

The "too dry" is almost as annoying as the "it's too warm to stick" it's not impossible on both it just makes it harder. It makes it a lot harder, yes. But it's not impossible, or unheard of.

[Ntxw]

The "too dry" is almost as annoying as the "it's too warm to stick" it's not impossible on both it just makes it harder. It makes it a lot harder, yes. But it's not impossible, or unheard of.

It is very annoying, even more annoying when you think about places in the northern plains, foothills etc manage to squeeze out big snowstorms out of hardly any moisture (being away from bodies of water) in such arid climates that's sooo cold and dry...