Texas Winter 2019-2020

[gpsnowman]

While we await the next GFS, I just looked and DFW is 14 degrees warmer than Miami currently, 80 to 66. Unreal. Go Chiefs!!!!!

[Texas Snow]

I am actually a huge fan of sleet just before a good snow. Accumulates quickly on concrete and streets and sets the stage that the snow will stick to everything. Probably goes back to growing up and wanting the streets to be too bad for school.

[gboudx]

I am actually a huge fan of sleet just before a good snow. Accumulates quickly on concrete and streets and sets the stage that the snow will stick to everything. Probably goes back to growing up and wanting the streets to be too bad for school.

Speaking of school, about what time of day would this happen if it did?

[Cerlin]

18z GFS has shifted towards the NAM a little bit, as it seems progressive still but has shifted totals to the west with south of Abeline being the bullseye.

[bubba hotep]

After 4:00 pm and not seeing an updated AFD from FWD must mean there is significant coordination ongoing and lots of splitting of hairs

[orangeblood]

After 4:00 pm and not seeing an updated AFD from FWD must mean there is significant coordination ongoing and lots of splitting of hairs

Yeah, always tough at this range...but how many times have we seen the Euro and GFS bust on temps with these setups ? Re: Temps - The High res NAM has to be the way to go at this range, right ?

[bubba hotep]

After 4:00 pm and not seeing an updated AFD from FWD must mean there is significant coordination ongoing and lots of splitting of hairs

Yeah, always tough at this range...but how many times have we seen the Euro and GFS bust on temps with these setups ? Re: Temps - The High res NAM has to be the way to go at this range, right ?

At 60hr the 18z GFS is 38F at DFW and the 3k NAM is 35F but look at that warm layer. It will be hard to get deep cold air in fast with the current projected H5 setup.

[starsfan65]

After 4:00 pm and not seeing an updated AFD from FWD must mean there is significant coordination ongoing and lots of splitting of hairs

Yeah, always tough at this range...but how many times have we seen the Euro and GFS bust on temps with these setups ? Re: Temps - The High res NAM has to be the way to go at this range, right ?

At 60hr the 18z GFS is 38F at DFW and the 3k NAM is 35F but look at that warm layer. It will be hard to get deep cold air in fast with the current projected H5 setup.

https://i1.pivotalweather.com/sounding_images/nam4km_2020020218_060_32.97--97.03.png

what does this mean?

[Texas Snow]

After 4:00 pm and not seeing an updated AFD from FWD must mean there is significant coordination ongoing and lots of splitting of hairs

Ask and ye shall receive



&&

.LONG TERM... /NEW/
/Tuesday through Next Weekend/

The primary weather headline in the extended forecast revolves
around winter precipitation during the mid-week period. At this
time, it`s appearing increasingly likely that there will be
accumulating snow and ice across parts of North Texas and the Big
Country. Some travel disruptions are possible, especially west
and north of the D/FW Metroplex. There remains a decent amount of
uncertainty with the mid-week system, so be sure to check back for
updates to the forecast. The one certainty is that it will turn
sharply colder for all areas by Wednesday morning. With strong
north winds of 15 to 25 MPH (gusts to near 30 MPH), it`ll feel
even colder Wednesday with apparent temperatures in the teens and
twenties.

A strong cold front should be on our doorsteps (or even south of
the Red River) at the start of the period on Tuesday. The latest
deterministic NAM and GFS guidance remain aggressive with
output from the TTU WRF and 3km NAM supporting a faster FROPA.
While the ECMWF has trended colder, it still remains on the warmer
side of the guidance envelope. As noted, the initial surge of
colder air is likely to be shallow in nature and typically
outpaces what is advertised in coarser guidance such as the ECMWF.
As such, I`ll lean heavily on the faster NWP. Confidence IS
increasing that temperatures across most of North Texas will fall
through the day with high temperatures likely being set before
noon. It will also turn quite blustery in the wake of the front
and a Wind Advisory will likely be required for parts of the area.
Farther south across Central Texas, the frontal blow torch will
be quite operational as high temperatures soar into the mid to
upper 70s. Some locations down across the Brazos Valley could see
temperatures near 80 degrees.

The fast moving nature of the front will mean low convective
chances as the boundary will likely undercut updrafts before they
can mature. At this time, the better rain and isolated storm
chances will be across East Texas where slightly better moisture
will exist. Widespread severe weather does not appear probable at
this time, though if the front slows some, this could mean that
updrafts may sustain themselves a bit longer and be capable of
producing small hail and gusty winds. This threat appears to be on
the lower end of the probability envelope and we`ll abstain from
advertising any severe weather risk.

The "fun" begins late Tuesday night into Wednesday morning as
a deeper fetch of colder air invades from the north. This seems
increasingly likely after midnight for areas near and west of a
U.S. Highway 281 corridor. Strong WAA atop the colder surface
airmass is expected to commence across the northern Hill Country
and up through the Concho Valley. A band of strong 700-850mb
frontogenetical forcing will likely establish itself in a
southwest to northeast fashion somewhere across the region. The
band of greatest precipitation theoretically should fall near and
northwest of this region of strong ascent. At the current time,
the 850mb front is forecast to stretch near and along a line from
near Eastland to Sherman/Denison. Near and northwest of this line,
I believe that initially rain/freezing rain will transition to
predominantly a snow/sleet mix. It is here that the potential for
1 to 3" of snow will exist Tuesday night into Wednesday. Forecast
soundings still indicate decent omega (ascent) within the
dendritic growth zone for parts of the Big Country. With some
marginal instability, convective banding could result in higher
snowfall amounts than currently advertised.

Farther to the southwest near a Paris to D/FW to Goldthwaite line,
is where the threat for a mix rain/freezing rain/sleet will be
greatest. With current temperatures advertised to be in the 31-32
degree range with precipitation, any icing should be limited to
bridges and overpasses. However...if north winds are around 15 to
20 MPH...additional CAA/evaporative cooling may knock those
temperatures down into the upper 20s. If this occurs...a
substantial icing event would be a lot more probable for locations
along the I-35 corridor...including the D/FW Metroplex. At this
time, I`ll advertise a trace to a few hundredths of an inch of ice
accumulation here. If convective elements become embedded within
this zone of mixed precipitation, a transition to more of a
snow/sleet precipitation type could transpire. This would boost
the accumulation of snow/sleet upward closer to the I-35 corridor.

Finally...areas across East Texas and the Brazos Valley will
likely initially experience a cold rain. An eventual transition to
light freezing rain may be possible as colder air invades from
the north.

Now where can the forecast go awry? The first is the speed of the
surface cold air. If the ECMWF solution is to verify...most areas
of North and Central Texas will only experience a cold rain...with
a low risk for a light winter mix across extreme western North
Texas and the northern Big Country (areas near an Eastland to
Graham line) due to warmer conditions and aloft. On the other
hand, if the deeper colder air does invade (closer to the GFS
solution) and spill over more of the area...the areal coverage of
a snow/sleet mix will be greater (and probably higher
accumulations).

Here are some of the key takeaways. The first is that there still
remains some uncertainty with precipitation types and amounts.
However, I`m confident that locations west of U.S. HWY 281 and
north of I-20 should definitely make preparations for winter
weather impacts. While there`s a little less certainty elsewhere,
we encourage interests to keep close tabs on the forecast.
Finally, it WILL turn significantly colder for all of the area, so
do not be caught off guard by the rapid drop in temperatures for
some areas Tuesday into Wednesday.

Bain

[Brent]

Yeah, always tough at this range...but how many times have we seen the Euro and GFS bust on temps with these setups ? Re: Temps - The High res NAM has to be the way to go at this range, right ?

At 60hr the 18z GFS is 38F at DFW and the 3k NAM is 35F but look at that warm layer. It will be hard to get deep cold air in fast with the current projected H5 setup.

https://i1.pivotalweather.com/sounding_images/nam4km_2020020218_060_32.97--97.03.png

what does this mean?

Warm layer is bad ice if it's cold enough or just rain

Like I see FWD mentioned

[starsfan65]

At 60hr the 18z GFS is 38F at DFW and the 3k NAM is 35F but look at that warm layer. It will be hard to get deep cold air in fast with the current projected H5 setup.

https://i1.pivotalweather.com/sounding_images/nam4km_2020020218_060_32.97--97.03.png

what does this mean?

Warm layer is bad ice if it's cold enough or just rain

To me Euro is an outlier.

[bubba hotep]

Yeah, always tough at this range...but how many times have we seen the Euro and GFS bust on temps with these setups ? Re: Temps - The High res NAM has to be the way to go at this range, right ?

At 60hr the 18z GFS is 38F at DFW and the 3k NAM is 35F but look at that warm layer. It will be hard to get deep cold air in fast with the current projected H5 setup.

https://i1.pivotalweather.com/sounding_images/nam4km_2020020218_060_32.97--97.03.png

what does this mean?

[Haris]

NWS has 40% chance of snow in West Austin for Thu am. Fingers crossed!!!

[Brent]

The GEFS is headed the wrong way for DFW. More than half have zero

[DonWrk]

The GEFS is headed the wrong way for DFW. More than half have zero

Here we go...

[Texas Snow]

Ruh roh

[starsfan65]

Ruh roh

Ruh roh?

[gpsnowman]

Ruh roh

Ruh roh?

When Scooby Doo senses danger he says Rhu roh. Because he can't say Uh oh. Dogs have a difficult time saying that.

[starsfan65]

Ruh roh

Ruh roh?

When Scooby Doo senses danger he says Rhu roh. Because he can't say Uh oh. Dogs have a difficult time saying that.

you guys look at 1 run of the GEFS and ya'll are worried.

[Brent]

Ruh roh?

When Scooby Doo senses danger he says Rhu roh. Because he can't say Uh oh. Dogs have a difficult time saying that.

you guys look at 1 run of the GEFS and ya'll are worried.

It's not one run though it's been decreasing all day if you look at it

Almost unanimous at 6z to less than half since

It should be noted it's much closer to the EPS now which is basically an average of 0.4 inches at the airport