Texas Winter 2013-2014

[TeamPlayersBlue]

You guys have had so many winter wx events this year. Super jealous. This winter is by far the craziest ive been throguh so far. Insane amount of fronts. All of these fronts are so shallow though.

As far as the mountains in SE OK, JB mentioned that it also creates a downsloping effect which heats up the air on the leeward side. Eventually it will fill in though.

I wish SE tx had a significant event with all these cold spells.

HGX is carefully monitoring and suggesting the may have to issue a Winter Weather Advisory for portions of SE Texas later today.

[Ntxw]

Currently at DFW Airport obs: 25F Thunderstorm, Light snow, Fog/Mist N winds 20mph. March is the new January.

[katheria]

from our awe inspiring CAVANAUGH....

000
FXUS64 KFWD 021918
AFDFWD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FORT WORTH TX
118 PM CST SUN MAR 2 2014

.UPDATE...

EXPANDED THE WINTER STORM WARNING SOUTHWEST TO INCLUDE THE DALLAS-
FORT WORTH METROPOLITAN AREA JUST BEFORE NOON. THIS DECISION WAS
MADE PRIMARILY DUE TO TWO PIECES OF EVIDENCE:

1. TEMPERATURES WERE ALREADY IN THE MID 20S FOR MOST OF THE AREA
WHERE THE WINTER STORM WARNING WAS EXPANDED INTO.

EVEN LIGHT PRECIPITATION WAS STARTING TO CAUSE PROBLEMS...AND
MPING (THE RESEARCH SMART-PHONE APP) REPORTS CONSISTENTLY
INDICATED THE PRESENCE OF SLEET FALLING A FEW HOURS BEFORE
FREEZING RAIN WAS EXPECTED TO TRANSITION OVER TO SLEET. WE WILL
NOT BE GETTING ANY WARMER DURING THIS EVENT...SO MORE
PRECIPITATION FALLING AS SLEET IS GOING TO CAUSE PROBLEMS ON
PRIMARY ROADWAYS AND NOT JUST ELEVATED SURFACES.

2. INFRARED SATELLITE AND REGIONAL RADARS WERE SHOWING CONVECTIVE
ELEMENTS DEVELOPING FROM SHERMAN SOUTHWEST TO AZLE A FEW HOURS
BEFORE THE PRIMARY FORCING ASSOCIATED WITH THE SHORTWAVE TROUGH
ARRIVED OVER NORTH TEXAS. AS FORCING FOR ASCENT ASSOCIATED WITH
THE SHORTWAVE MOVES OVER THE REGION FROM WEST TO EAST...CONVECTION
IS ONLY EXPECTED TO EXPAND IN COVERAGE. THE FACT THAT CONVECTION
WAS BEGINNING AHEAD OF THE TROUGH JUST MEANS MORE OPPORTUNITY FOR
ICE/SLEET ACCUMULATIONS.

METEOROLOGICAL REASONING:
A 1630Z AIRCRAFT RAOB FROM DALLAS LOVE FIELD OBSERVED A RELATIVELY
SHALLOW...BUT VERY COLD...LOW LEVEL AIR MASS OVER NORTH TEXAS. THE
LOWEST TEMPERATURE IN THE COLD AIR WAS OBSERVED AT -8 DEG C. ABOVE
THE FRONTAL INVERSION...THERE WAS STILL QUITE A WARM NOSE IN PLACE
WITH A TEMPERATURE OF PLUS 11 DEG C JUST ABOVE THE 850 MB LEVEL.
PRECIPITATION FALLING THROUGH THIS VERTICAL THERMAL PROFILE FROM
ALOFT MUST BE IN A LIQUID FORM BEFORE REACHING THE LOW-LEVEL COLD
AIR MASS. THIS SEEMINGLY LIMITS OUR PRECIPITATION OPTIONS TO
FREEZING RAIN OR SLEET.

HOWEVER...TO THE WEST OF THE DFW AREA...SNOW IS BEING
CONSISTENTLY REPORTED FROM THE PUBLIC VIA SOCIAL MEDIA AND MPING
REPORTS. SO WHAT IS HAPPENING? WHILE IT IS DIFFICULT TO KNOW FOR
SURE...WHAT IS LIKELY TAKING PLACE IS THAT THE SHALLOW BUT VERY
COLD LOW-LEVEL AIRMASS HAS COOLED DOWN TO -10 DEG C OR BELOW TO
THE WEST AND NORTHWEST OF THE DFW AREA (WHERE WE HAVE AIRCRAFT
OBSERVATIONS AVAILABLE). AT -10 DEG C TO APPROXIMATELY -20 DEG
C...WATER DROPLETS TEND TO CRYSTALLIZE INTO DENDRITE SHAPED
CRYSTALS. THE MIXTURE OF CRYSTALS AND LIQUID WATER THAT IS
SUPERCOOLED (BELOW FREEZING BUT STILL IN LIQUID FORM) PROMOTES THE
GROWTH OF THE DENDRITE CRYSTALS AT THE EXPENSE OF THE SUPERCOOLED
WATER DROPLETS...PROMOTING A PRECIPITATION TYPE PRIMARILY
DOMINATED BY SNOW AS OPPOSED TO FREEZING RAIN OR SLEET. AT ANY
RATE...WENT AHEAD AND INTRODUCED SNOW TO THE BACKSIDE OF THE
PRECIPITATION SHIELD AS OUR LOW-LEVEL AIR MASS DOES IN FACT LOOK
COLD ENOUGH TO SUPPORT SNOW GROWTH VERY CLOSE TO THE
SURFACE...WHICH IS PRETTY EXTRAORDINARY FOR NORTH TEXAS.

WENT AHEAD AND BUMPED UP THE FORECAST FOR SLEET/SNOW ACCUMULATIONS
TO ONE HALF INCH FOR THE ENTIRE WINTER STORM WARNING AREA. LEFT
ICE ACCUMULATIONS ALONE...OR SLIGHTLY DECREASED AMOUNTS SOMEWHAT
DUE TO A SEEMINGLY SMALLER WINDOW FOR TRUE FREEZING RAIN BEFORE
PRECIPITATION CHANGES OVER TO SLEET. SLEET ACCUMULATIONS WILL
LEAVE ROADWAYS VERY SLICK...ESPECIALLY WHERE THUNDERSTORMS ARE
THROWN INTO THE MIX. THE THREAT FOR THUNDERSTORMS WILL REMAIN
THROUGHOUT MOST OF THIS EVENT. ANYWHERE STORMS OCCUR...LOCALIZED
HEAVY ACCUMULATIONS OF SLEET ARE EXPECTED. MOST OF THESE SLEET
PRODUCING STORMS SHOULD BE CONTAINED WITHIN THE WINTER STORM
WARNING...HOWEVER ANYWHERE THERE IS A THUNDERSTORM AND THE
TEMPERATURES ARE IN THE MID 20S...YOU CAN EXPECT QUICK SLEET
ACCUMULATIONS OF UP TO ONE HALF INCH IN AN HOUR. THIS WILL
OBVIOUSLY LEAD TO LOCALIZED POCKETS OF HAZARDOUS
ROADWAYS...REGARDLESS OF WHETHER YOU ARE IN A WINTER STORM WARNING
OR A WINTER WEATHER ADVISORY.

LASTLY...WHAT WE WILL BE WATCHING CLOSELY THIS AFTERNOON ARE THOSE
COUNTIES SOUTH OF THE WINTER WEATHER ADVISORY. WE DID NOT EXPAND
THE ADVISORY SOUTH JUST BEFORE NOON BECAUSE TEMPERATURES WERE
HOVERING NEAR OR JUST BELOW FREEZING. WE HAVE CONSISTENTLY HAD
REPORTS OF LITTLE TO NO IMPACTS FROM WINTRY PRECIPITATION UNTIL
TEMPERATURES DROP INTO THE MID 20S...SO WITH THOSE LOCATIONS TO
THE SOUTH OF THE ADVISORY HOLDING ON TO TEMPERATURES IN THE LOWER
30S...THOUGHT THAT THERE WOULD BE LITTLE IMPACTS ON AREA ROADWAYS
AT THIS TIME. THE PREVIOUS 48 HOURS SAW HIGHS INTO THE 80S FOR
MANY OF THESE LOCATIONS...SO IT REALLY WILL TAKE SOME COLD AIR FOR
IMPACTS TO BEGIN ACROSS THE WACO/TEMPLE/KILLEEN/LAMPASAS AREAS
THIS AFTERNOON. THAT SAID...WE WILL BE WATCHING CLOSELY FOR
TEMPERATURES THAT DROP INTO THE MID 20S WHILE SIGNIFICANT
PRECIPITATION IS STILL POSSIBLE. THESE LOCATIONS WILL SEE
TEMPERATURES DROP INTO THE 20S EVENTUALLY...BUT MOST PRECIPITATION
IS EXPECTED TO END AS WE GET DRY SLOTTED FROM WEST TO EAST LATE
THIS AFTERNOON THROUGH THIS EVENING BEFORE THAT OCCURS.

WE WILL CONTINUE TO CLOSELY MONITOR THIS WINTER WEATHER
EVENT...AND BROADCAST OUT ANY SIGNIFICANT CHANGES TO THE FORECAST
AS QUICKLY AS POSSIBLE

[Tireman4]

This is going to get interesting

[Ellsey]

Drove from Melissa to McKinney in very heavy sleet. Saw some lightning as well. Builds up very quickly on the roads. They were passable but getting very nasty.

[srainhoutx]

Pea sized hail with freezing rain reported in Waco.

[Ralph's Weather]

Nothing but a cold rain earlier in Lindale, temp is now right around freezing.
It is very interesting to hear about site forming in the very shallow cold air.

[iorange55]

Nothing heavy here yet, but the sleet/flurry mix has picked up in the last 30 minutes or so.

[uptowndallas]

Very light snow and sleet falling now in Dallas. Mostly blowing away but some light accumulation on cars.

[TheProfessor]

getting dry slotted now

[TrekkerCC]

I can confirm the light sleet/very light snow mix in Plano area now.

[TheProfessor]

light snow here

[SeGaBob]

I'm jealous of the winter weather you all are getting over there... We're sitting at a warm 73 here.

[Texas Snowman]

HEAVY thunder sleet storm in Denison right now. Roads totally covered in sleet. Probably 1/2 inch or more.

[TexasSam]

Partly cloudy and 78 here...

[iorange55]

WFAA Local met just came on television and announced the band out by Decatur would be the last band.


Hmmm.

[orangeblood]

Outside of heavy sleet bands, warm ground temps and daylight are helping to keep roads wet attm

[Wntrwthrguy]

Looks like the rain is ending for the Austin area. Wish we could have received more rain but we will take what we can get these days.

As for tomorrow night, if it isn't going to snow, I hope it stays warm enough for all rain. Freezing rain,in any amount, is not fun.

[iorange55]

Heaviest precip I've seen all day moving through right now. The wind is really blowing everything around out there. Looks like a mini-blizzard.

[Texas Snowman]

Current observation at North Texas Regional Airport just west of Denison:

Thunderstorm / Light Snow

22°F

-6°C