Texas/New Mexico/Louisiana/Mexico Obs And Discussion Thread Part 4

[bubba hotep]

Grasping at straws on this one but still foolishly holding out hope:

000

FXUS64 KFWD 080003

AFDFWD

AREA FORECAST DISCUSSION

NATIONAL WEATHER SERVICE FORT WORTH TX

.PREV DISCUSSION... /ISSUED 343 PM CST FRI DEC 7 2012/

...TURNING MUCH COLDER LATE SUNDAY THROUGH MID WEEK...

...LIGHT SNOW WITH MINOR ACCUMULATIONS POSSIBLE SUNDAY NIGHT INTO

EARLY MONDAY ALONG/NORTHWEST OF A BRECKENRIDGE-GAINESVILLE LINE...

A BUSY FORECAST PACKAGE IS AT HAND...AS WE ASSESS SEVERAL FORECAST

CHALLENGES OVER THE WEEKEND AND INTO EARLY NEXT WEEK. THE WEAK

COLD FRONT THAT PUSHED THROUGH THE NORTHWEST HALF OF THE CWA EARLIER

TODAY HAS LIFTED BACK TOWARD THE RED RIVER THIS AFTERNOON IN

ADVANCE OF A SHORTWAVE NOW MOVING ACROSS FAR WEST TEXAS AND

NORTHERN MEXICO. HIGHS TODAY HAVE WARMED BACK INTO THE LOWER 70S

SOUTH OF THE FRONT WITH LIMITED SBCAPE...BUT STEEPENING LAPSE

RATES NOW UP TO 7.5 DEG C/KM ACROSS THE AREA. THE SHORTWAVE SHOULD

AFFECT NORTH TEXAS DURING THE EVENING AND OVERNIGHT AND HELP MOVE

A WEAK SURFACE LOW OVER SOUTHEAST OKLAHOMA EAST AND DRAG THE WEAK

FRONT BACK SOUTH AGAIN. BEST MOISTURE AND LIFT WILL BE FOCUSED

ACROSS OUR EASTERN COUNTIES. MADE ONLY MINOR UPGRADE TO LOW CHANCE

POPS EAST OF THE DFW METRO AND UPGRADED TO ADD A FEW THUNDERSTORMS

INTO THE FORECAST TONIGHT. THE FRONT APPEARS TO STALL AGAIN BEFORE

SUNRISE FROM ATHENS...TO HILLSBORO/WACO...TO THE HAMILTON AREAS

AND WITH WEAKENING SOUTH WINDS AND NEAR SATURATED BOUNDARY

LAYER...EXPECT LOW CLOUDS AND PATCHY FOG TO OCCUR ALONG AND SOUTH

OF THE FRONT SATURDAY MORNING. THE FOG WILL READILY BURN OFF AS

THE WEAK FRONT RETREATS NORTH ONCE AGAIN WITH PARTLY SUNNY AND

MILD CONDITIONS AGAIN BY AFTERNOON. SATURDAY NIGHT WILL REMAIN ON

THE WARM SIDE AS THE A NOCTURNAL LLJ INCREASES AHEAD AMPLIFYING

LONGWAVE TROUGH OVER THE ROCKIES. THE LOW CLOUDS AND BREEZY SOUTH

WINDS WILL KEEP LOWS UP IN 50S/60S MOST AREAS EXCEPT FOR THE FAR

NORTHWEST.

WE NOW MOVE ONTO SUNDAY INTO MONDAY. THE 12Z MODELS DID NOT DIFFER

TOO MUCH AWAY FROM THE PREVIOUS 00Z RUNS IN THAT THEY WANT TO

CONTINUE WITH A BIG DEEPER/SLOWER OPEN TROUGH WITH A SLIGHTLY

SLOWER COLD FRONT ARRIVAL. IT APPEARS STRONGER SHORTWAVE ENERGY

HAS DELAYED MOVING DOWN THE BASE OF THE ROCKIES AND HIGH PLAINS

UPPER TROUGH UNTIL LATER ON SUNDAY. HAVE TAKEN A MEAN BETWEEN THE

MORE PROGRESSIVE GFS/NAM AND SLOWER GEM/ECMWF MODELS ON THE TIMING

AND HAVE THE FRONT MOVING INTO THE NORTHWEST COUNTIES JUST BEFORE

MIDDAY SUNDAY...THEN MOVING SOUTH OF INTERSTATES 20/30 DURING THE

LATER AFTERNOON HOURS.

MID LEVEL HEIGHT FALLS WILL BE MOST IMPRESSIVE DURING THIS TIME

AND INTO THE EVENING HOURS WITH BEST CHANCES FOR SHOWERS AND

THUNDERSTORMS ACROSS THE SOUTHERN AND EASTERN CWA WHEN THE HEIGHT

FALLS COMBINE WITH FORCING ALONG THE STRONG FRONT FOR A FEW

STRONGER THUNDERSTORMS WITH GUSTY WINDS AND SOME HAIL. BEHIND THE

FRONT...TEMPERATURES DURING THE DAY SUNDAY WILL LIKELY DROP

THROUGH THE 60S AND INTO THE UPPER 40S/50S WITH GUSTY NORTH WINDS

ACROSS OUR NORTHERN CWA. STRONG CAA WILL ENSUE WELL BEHIND THE

FRONT INTO MONDAY MORNING...BUT WITH OUR MAIN PIECE OF UPPER

ENERGY LINGERING ACROSS THE SOUTHERN ROCKIES AND OK/TX PANHANDLES

THROUGH MIDNIGHT MONDAY.

THE STRONG SHORTWAVE ENERGY AND ASSOCIATED/INCREASING MID LEVEL

FRONTOGENESIS AND DPVA LOOK TO ROTATE ACROSS THE RED RIVER VALLEY

PREDAWN THROUGH EARLY AFTERNOON ON MONDAY. WITH A BROAD MERIDIONAL

LONGWAVE TROUGH MOVING ACROSS THE COUNTRY...THE PATTERN IN LOCAL

STUDIES IS KNOWN AS BASICALLY /THE NORTH AMERICAN TROUGH/ SET UP

IN THE WINTER TIME. IT BASICALLY HAS NO TELECONNECTION TO THE

SUBTROPICAL BRANCH OF THE UPPER JET AND THE DEEP COLD AIR

ASSOCIATED WITH IT BEHIND COLD FRONTS WILL SHUT DOWN LOW LEVEL

MOISTURE TRANSPORT FROM THE GULF OF MEXICO...WHICH IN THIS CASE

GETS SHUNTED EAST ACROSS THE ARKLATEX AND LOWER MISSISSIPPI

VALLEY. HOWEVER...WITHIN THE STRONG FRONTOGENETICAL FORCING ALOFT

USUALLY BETWEEN 600-700 MB...ELEVATED AND ELONGATED LIGHT SNOW

BANDS CAN FORM. PER MODEL ENSEMBLES THE CONSENSUS BETWEEN ALL THE

MODELS ON ANY MID LEVEL BANDING APPEARS TO BE ALONG AND NORTH OF A

BRECKENRIDGE TO GAINESVILLE LINE AND WILL LIKELY OCCUR ONLY FOR

3-6 HRS AT ITS PEAK AS THE STRONG JET MAX AND SHORTWAVE ROTATE

THROUGH THE BASE OF THE MAIN CENTRAL CONUS LONGWAVE TROUGH. WITH

UNCERTAINTY STILL EXISTING ON LOWER LEVEL MOISTURE AVAILABILITY...

WE HAVE RAISED THOSE NORTHWEST COUNTIES INTO THE CHANCE CATEGORY...

WITH SLIGHT CHANCES/FLURRIES STILL POSSIBLE 50-100 MILES SOUTH AND

EAST OF THE MAIN BAND TOWARD A BONHAM...DFW...COMANCHE LINE FOR NOW.

WE MUST STRESS THAT STRENGTH/MOISTURE/TIMING UNCERTAINTIES REMAIN

AND THUS NO ACTUAL ACCUMULATIONS WILL BE PREDICTED THIS FAR

OUT...BUT URGE EVERYONE TO MONITOR OUR UPDATED FORECASTS THROUGH

THE WEEKEND.

THE SYSTEM WILL EXIT THE AREA ABOUT AS FAST AS IT ENTERED WITH

SUBSIDENCE AND PARTIAL CLEARING OCCURRING BY MONDAY AFTERNOON. IT

WILL REMAIN BRISK AND CHILLY INTO THE EVENING HOURS MONDAY.

CLEARING SKIES AND DIMINISHING WINDS WILL MAKE FOR OUR COLDEST

MORNING OF THE WEEK TUESDAY AND A HARD FREEZE. LOWS TUESDAY WILL

RANGE FROM THE UPPER TEENS/LOWER 20S NORTH...TO THE MID-UPPER 20S

SOUTH. THE DEEP AND BROAD MERIDIONAL TROUGH WILL REMAIN ALONG AND

EAST OF THE ROCKIES INTO MID WEEK...WHICH MEANS ONLY SLOW

MODIFICATIONS TO HIGHS/LOWS EACH DAY INTO WEDNESDAY AND DRY

CONDITIONS. WE HAVE CONTINUED TO CUT MOS TEMPERATURES THROUGH

TUESDAY WITH MOS BIASES IN SUCH DEEP COLD PATTERNS TO TRY TO WARM

AND MODIFY SUCH AIRMASSES TOO QUICKLY. BY WEDNESDAY INTO THURSDAY...

THE TROUGH LOSES ITS GRIP ON THE PLAINS AND SHIFTS EAST AND GETS

REPLACED WITH A SHORTWAVE UPPER RIDGE. THIS WILL ALLOW TEMPERATURES

TO MODIFY AND WARM BACK INTO THE THE 50S/60S FOR HIGHS THURSDAY

INTO SATURDAY.

THERE ARE SIGNS OF ANOTHER STRONG SHORTWAVE TROUGH AFFECTING THE

SOUTHERN PLAINS NEXT FRIDAY NIGHT AND THE WEEKEND. THIS TROUGH

LOOKS TO BE MORE OF THE DETACHED TROUGH VARIETY WITH COLDER AIR

REMAINING BOTTLED UP ACROSS THE NORTHERN CONUS. AT THIS TIME...HAVE

LEFT THE FORECAST DRY WITH THIS PERIOD BEING JUST BEYOND OUR 7 DAY

FORECAST. HOWEVER...IT DOES BEAR WATCHING FOR OUR NEXT SHOT OF

OF RAINFALL.

05/

[Srain]

Morning e-mail from Jeff:

Powerful Canadian cold front sweeping down the plains will end the record warmth tonight!

Freezing temperatures expected both Tuesday and Wednesday mornings.

Surface observations show the strong cold front plowing through the TX panhandle and moving S at 25-35mph. Temperatures ahead of the boundary are in the 60’s and 70’s and fall rapidly into the 40’s behind the front with strong NW winds. Front may slow up a little today with warm air mixing along the leading edge, but there should be a good push after dark to bring the boundary and its associated weather into SE TX tonight. While the front approaches from the north, moisture continues to increase from the Gulf ahead of a short wave disturbances currently approaching the Rio Grande. Large scale lift will be increasing this afternoon and expect to see scattered showers begin to develop and move northward from the coast. By this evening strong surface lift with the frontal boundary will come to bear across the area with numerous showers and thunderstorms developing. A few storms could be strong to severe. SPC has placed areas along and north of I-10 in a slight risk for wind damage this evening, but the overall severe threat is on the low side given only marginal instability and shear. System looks fairly similar to the one this past Tuesday with greatest rain chances and coverage mainly across our central and eastern counties with amounts to the west and southwest less as drier mid level air and SW winds in the mid level affect this region.

Front blasts off the coast by sunrise with strong cold air advection ensuing. Highs temperatures will be a midnight with temperatures falling through much of the morning on Monday into the low 40’s north to near 50 at the coast under strong N winds of 15-25mph and gusty. Clouds will slowly clear from WNW to ESE during the afternoon and this clearing may result in a small rebound in temperatures from 3-5pm on Monday if at all.

Center of the large polar high will be west of SE TX on Monday night and expect weak N winds to continue. Given the very dry air mass in place with dewpoints forecasted well into the 20’s, sub-freezing temperatures can be expected for nearly all areas except within the 610 loop (urban heat island) and right along the coast. Many areas will see freezing temperatures for 3-6 hours and a freezing warning will be required for most counties even those that have already had a freeze due to the recent warmth. Highs on Tuesday even under sunny skies will only reach the low to mid 50’s.

Tuesday night and Wednesday morning look to be near ideal for maximum cooling with the polar high nearly overhead and calm winds under crystal clear skies. Temperatures will plunge after sunset and many areas will fall below freezing for 4-8 hours. Could see mid 20’s up north to near 30 at the coast with mainly 29-32 for most areas. Pipes will not be an issue with this cold event, but sensitive tropical plants will likely sustain damage if not protected.

Slow warm up begins on Thursday with highs recovering into the 60’s and the 70’s by Friday under increasing chances of rainfall.

[Ed Lizard]

Baby WAA showers under the cap...

Not so baby showers closer to the front...

Northern/Northwestern HOU suburban counties still in updated SWODY1 Slight Risk area, and my house, not in a risk, but better thqan 5% wind and hail, glass quarter full optimism.

At least the cold weather is during the work week, and won't kill plants generally appropriate for Houston. Not some McFarland type 4 days below freezing and lows in the teens with over half the palm trees and Tio Jose's grapefruit trees dying stuff. (We have a big bowl of Tio Jose's grapefruits in the kitchen. Tio lives near HOU, in the urban heat island, pretty sure I couldn't grow them North of the Beltway. Seen banana plants with fruit in the city, a sign the surface foliage survived the Winter, which never happens in my neighborhood.)

[Ed Lizard]

^^ Radar hotlink getting happier locally...

[DoctorMu]

Good to see some wet stuff!

[DoctorMu]

Rain gauge says about 3 in so far - wow.

[Ed Lizard]

Weakening as it approaches my lawn. I suspect a quarter inch. And I'm being optimisitic.

But a football game w/ snow is on TV.

[DoctorMu]

^Snow approaching Bowie and DFW area

[DoctorMu]

Band of SNOW nearing Carrollton and Fort Worth. Good chance of White Stuff before 8 am.

Denton seeing wintry mix.

[bubba hotep]

Snow!! Just a dusting but better than nothing. Will try to get some pics after I drop my daughter off at school.

Overperformer!!

[Quixotic1]

Snow!! Just a dusting but better than nothing. Will try to get some pics after I drop my daughter off at school.

dusting here in frisco. more than last wintwr!

[Srain]

Wichita Falls Webcam:

[DoctorMu]

Weakening as it approaches my lawn. I suspect a quarter inch. And I'm being optimisitic.

But a football game w/ snow is on TV.

3.7 in final tally, almost 2 in better than the airport as we got trained a bit. Nice to finally shut down the sprinklers for the season...before the next one starts!

We've been really parched in the Fall.

[Ed Lizard]

3.7 in final tally, almost 2 in better than the airport as we got trained a bit. Nice to finally shut down the sprinklers for the season...before the next one starts!

We've been really parched in the Fall.

Between a tenth and a quarter judging from radar, DWH and IAH. Trivial.

[Quixotic1]

View this mornin'

[Srain]

E-mail from Jeff:

Freezing warning will be issued this afternoon for all areas except inside the 610 loop and the immediate coastal areas.

Long awaited and well advertised cold blast arrive overnight with current temperatures running some 20-30 degrees colder than this time on Sunday.

Strong Canadian cold front continues to plow across the Gulf of Mexico as large polar high builds down into central TX. Strong cold air advection continue early this afternoon under slowly clearing skies from the NW. Even under sunny skies temps. remain in the 40’s with gusty NNW winds of 15-25mph. Large surface high will expand into SE TX this evening with winds weakening, but not likely going calm. Air mass is already very dry with dewpoints in the 20s and once the sun sets, temperatures will begin to fall toward those dewpoints. Weak overnight winds will keep temperatures from bottoming out near the bone dry dewpoints and save most of the region from a hard freeze.

Lows Tuesday/Wednesday AM:

27-29: north of HWY 105

29-32: all other areas

33-35: inside 610 loop and beaches

Temperatures will be at or below freezing for between 3-7 hours. Sensitive tropical vegetation will be impacted and should be protected.

Warming only into the low to mid 50’s on Tuesday with polar high moving nearly overhead by late afternoon. Winds will be weaker (near clam) Tuesday night/Wednesday morning and equally cold temperatures are likely again. Would go a little lower on the Wednesday morning lows, but the surface ridge axis may shift just enough eastward to allow a very weak E wind toward morning which could halt the temperature fall.

Warm up begins on Thursday as the polar high moves eastward and SE winds return to the area. Gulf moisture will begin to deepen as low pr3essure develops over the southern plains supporting southerly flow. Models have been waffling back and forth with rain chances for the Friday-Saturday period. What looked to be a decent chance of rain yesterday is much more questionable today and given the drought conditions in place…will side with the drier side of things for now. Temperatures will rebound back toward the 70’s for highs and 50’s for lows by Saturday ahead of a weak front late Saturday which will return the area to normal.

[Ed Lizard]

3º C difference at 6am, between not a freeze and a hard one, between Hooks and Intercontinental. I suspect just a shade of urban heat island with all the terminal buildings and d runways and taxiways. Another degree warmer (2º C) at Hobby, deeper in the heat island.

My delicate plants, no doubt, are closer to 28ºF

[Srain]

The 12Z operational GFS has trended toward what the overnight Euro operational and its ensembles suggested. A potent 500mb upper low develops a Winter Storm crossing the Southern Rockies/Southern Plains as the upper low closes off and becomes cold cored. The warm sector suggests a severe potential next Monday into Tuesday while in the cold sector more wintry mischief may be lurking. In fact as the upper low moves E, a full blown Deep S Blizzard develops.

Looking further ahead via the GFS, the very progressive pattern continues and the GFS is sniffing some mighty chilly air spilling S into the Plains extending well S along the Gulf Coast as a very cold Canadian High Pressure Ridge drops S and a strong blocking pattern keeps a suppressed Southern Storm Track near the Christmas Holidays. We will see.

[Srain]

Morning e-mail from Jeff:

Freeze ongoing across most of the area again this morning except for the urban heat cores and along the water front. Temperatures thus far are nearly equal to yesterday morning in most rural locations and running 1-2 degrees warmer in the urban heat centers. This will be the last morning of freezing temperatures, although a light freeze will be possible again tonight over our NE counties. Large polar high that has brought the cold weather will be shifting eastward as the next storm system digs down the US west coast and into the SW US by the end of the week. Light ENE winds will become east today and then SE on Thursday which will begin the return of low level moisture to the area. This past front while fairly strong, did not penetrate through the entire Gulf of Mexico, and a plume of deep moisture is in place over the southern Gulf with satellite derived PWs of 1.3-1.5 inches down around the Yucatan. As winds turn out of the SE this moisture will begin to move NW toward the lower TX coast as a warm front develops on Thursday.

Approaching storm system over the SW US will eject into the southern plains on Friday with a warm front moving northward into SE TX during the day. GFS shows a fairly robust surge on moisture late Friday into the area and while this seems at least possible, it may be overdoing the moisture return. Even so, expect scattered showers to develop in the afternoon with a strong southern branch jet stream overhead, a northward moving boundary, and increasing warm air advection. Area should fall into the warm sector by Friday night with muggy 60 degree dewpoints pushing inland ahead of a weak front moving into central TX on Saturday morning.

Latest guidance suggest the initial storm system will move off to the NE allowing its associated cold front to slow and stall across SE TX on Saturday afternoon. Previous model runs were suggesting this boundary would at least push into the offshore waters before stalling, and this is still possible. With the boundary stalling now either near the coast or possibly inland and with a noisy sub-tropical jet overhead with a series of impulse, rain chances will be continued in Sunday. In fact with the stalling boundary, good moisture pooling, and favorable lift from passing disturbances aloft, there is some potential for training rainfall this weekend. Looks like some decent rainfall amounts especially over the coastal and central counties from Friday through Sunday if the boundary does not push too far offshore.

Next upper level storm will swing through the southern plains on Monday and bring a stronger cold front through the area on Tuesday. This boundary should be able to push well into the Gulf of Mexico with much drier air and clearing/cooling in the post frontal air mass.

Cold temperatures today and again early Thursday will be replaced with lows in the 60’s and highs in the upper 70’s over the weekend.

[Srain]

Third night in a row with sub freezing temps for me and then the rain returns for the weekend. The next in a series of troughs with embedded short waves and a stalling Pacific front are a recipe for a heavy rainfall event as a noisy SJT feeds Pacific moisture across the region. High elevation snow for New Mexico and perhaps the Panhandle on into Oklahoma early next week as a stronger 5H low takes a Southern Track across the Region.

Lurking to the N in Western Canada, a 1055+ Arctic high is suggested by guidance to drop S into the Plains near the Christmas Holidays. The Euro and GFS have come into agreement that a favorable MJO may be in the works as well. Increased STJ moisture streaming over that shallow cold air may offer a chance of a Winter Storm near the 20th-22nd, +/- a couple of days. We will see.

[Portastorm]

No surprise that the GFS op runs overnight have backed off some on the very wintry scenario it was painting for Texas for Christmas week. Lots of volatility in the model runs until it can capture the changes ongoing in the atmosphere. Both the AO and NAO look to stay negative for much of the remainder of this month and we're seeing increasing signals that the subtropical jet will become much more active in the next 2-3 weeks. All of this suggests a more active and possible colder period ahead.

I also noticed the CFSv2 forecasts for the last week of December and first week of January have cooled considerably for Texas. Even more encouraging is that portions of Texas appear to be slightly wetter than normal during that period. Yeah, I'd love some real cold weather but at this point, and more importantly, I'd take any precip we can get!

[bubba hotep]

Decent shot of rain around our area this afternoon and the HRRR continues to insist that we will see a line of storms race across the area this evening. This is the 1st system in a long time that didn't "dry up" in the models in the days leading up to it. The GFS has been hinting that we could see another shot of rain around Christmas time.

[bubba hotep]

Finally some rain down in Waco:

[Ed Lizard]

THE MOST PROBABLE SCENARIO FOR STORM INTENSIFICATION MAY OCCUR

ACROSS PARTS OF SOUTHEAST TX INTO LA/PARTS OF MS SUNDAY AFTERNOON

AND SUNDAY NIGHT/EARLY MONDAY NEAR AN ADVANCING/ACCELERATING COLD

FRONT. SOMEWHAT STRONGER DESTABILIZATION IS LIKELY IN THESE AREAS IN

THE PRESENCE OF A HIGHER THETA-E AIRMASS...WITH THE REGION

INCREASINGLY COMING UNDER THE INFLUENCE OF THE AMPLIFYING UPPER

TROUGH OVER THE PLAINS/OZARKS BY SUNDAY NIGHT. WHERE STORMS DO

INCREASE/MATURE...VERY STRONG DEEP LAYER SOUTHWESTERLY FLOW AND

ASSOCIATED VERTICAL SHEAR OF 50-80 KT /0-6 KM/ WILL SUPPORT

FAST-MOVING LINE SEGMENTS/SOME SUPERCELLS WITH ASSOCIATED POTENTIAL

FOR DAMAGING WIND/ISOLATED TORNADOES.

CAPE and low level wind fields on GFS and NAM looks rather "meh", but deep layer shear looks stout. I'm not personally certain we have earned our SLIGHT RISK for tomorrow, but glass solid quarter full optimism with paid experts onboard.

[Srain]

Another rather sharp cold snap appears in the works late Wednesday into Thursday as a potent Winter Storm ejects out of the 4 Corners Region and heads NE into the Western Great Lakes dropping down another strong Canadian front.

[DoctorMu]

GFS leaning that way now. Missed it on the morning scan

[Srain]

The overnight guidance is coming into somewhat better agreement of a potent short wave/trough with another Winter Storm potential for New Mexico into the Panhandle and Western Oklahoma as a strong Canadian front moves across the Region on Wednesday. Freezing temps are again expected as far S as S Central/SE Texas and in the warm sector ahead of the front, Severe potential is increasing for NE TX/Southern Arkansas and Northern Louisiana and on into the Deep South for Thursday.

[Ed Lizard]

Glass overflowing optimisitic on a good soaking for the lawn this morning. OK, that is beyond NowCast into Hindcast territory...

[Srain]

Almost 2 inches of rain with the Pacific frontal boundary and short wave. All in all, not too shabby down here in SE Texas.

[Srain]

MESOSCALE DISCUSSION 2161

NWS STORM PREDICTION CENTER NORMAN OK

0954 AM CST SUN DEC 16 2012

AREAS AFFECTED...SE TX...SW/CENTRAL LA...SW/CENTRAL MS

CONCERNING...SEVERE THUNDERSTORM WATCH 682...

VALID 161554Z - 161730Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 682

CONTINUES.

SUMMARY...A PRE-FRONTAL BAND OF STRONG/SEVERE STORMS WILL PERSIST

FOR THE NEXT SEVERAL HOURS WITH THE POTENTIAL FOR ISOLATED DAMAGING

WINDS. THE WIND THREAT MAY ALSO SPREAD INTO SW/CENTRAL MS BY MIDDAY

AS THE LOW LEVELS WARM/MOISTEN.

DISCUSSION...AN EXTENSIVE PRE-FRONTAL BAND OF THUNDERSTORMS IS

MOVING SLOWLY SEWD ON WEAK CONVECTIVE OUTFLOW...WHILE INDIVIDUAL

CELLS MOVE QUICKLY ENEWD ALONG THE LINE. THE PRESENCE OF A MOIST

BOUNDARY LAYER /MID-UPPER 60S DEWPOINTS/ AHEAD OF THE STORMS FROM SE

TX INTO LA WILL SUPPORT REGENERATION OF STORMS ALONG THE COMPOSITE

OUTFLOW BOUNDARY THROUGH EARLY AFTERNOON. ADDITIONALLY...A FEW

STORMS COULD DEVELOP WITHIN THE WARM SECTOR AS THE BOUNDARY LAYER

WARMS/MOISTENS...AND THE RIGHT ENTRANCE REGION OF A STRONG UPPER JET

DEVELOPS ENEWD FROM TX TOWARD LA/MS. THE OVERALL SETUP STILL

APPEARS SUPPORTIVE OF PRIMARY EMBEDDED LINE SEGMENTS WITH AN

ATTENDANT RISK FOR ISOLATED DAMAGING WINDS...GIVEN MODEST

INSTABILITY S OF THE ONGOING STORMS AND LARGELY LINE-PARALLEL

DEEP-LAYER VERTICAL SHEAR. WHILE LOW-LEVEL SHEAR IS NOT

PARTICULARLY STRONG...ANY MORE DISCRETE STORMS THAT HAPPEN TO FORM S

OF THE BAND MAY POSE A MARGINAL TORNADO RISK.

..THOMPSON/CORFIDI.. 12/16/2012

ATTN...WFO...JAN...LIX...LCH...SHV...HGX...CRP...