JANUARY 2018 - Seasonal WX Week/Pacific Front Saturday

[stormlover]

https://www.tropicaltidbits.com/analysi ... 11601&fh=1

https://www.tropicaltidbits.com/analysi ... 11600&fh=6


https://www.tropicaltidbits.com/analysi ... 11600&fh=6

[Cromagnum]

That looks like a terrible slushy mess of freezing rain and sleet for Houston.

[srainhoutx]

The Arctic Boundary is approaching Austin at this time. Everything appears to be unfolding as expected for the 9 o'clock hour. Time for some shut eye for me. I'm sure Andrew and others will be around overnight providing Updates.

[sau27]

The 00z GFS is continuing the more aggressive trend, keeping frozen precip around a bit longer. But what's more impressive is that it keeps the area in the 20s throughout the daylight hours. Usually in these events we are hovering right at the freezing threshold but we look to be significantly below freezing most of the day which will only serve to increase the efficiency of ice accretion.

[DoctorMu]

The Arctic Boundary is approaching Austin at this time. Everything appears to be unfolding as expected for the 9 o'clock hour. Time for some shut eye for me. I'm sure Andrew and others will be around overnight providing Updates.

Snow in Dallas. Freezing precip changing over in Waco and Gatesville.

[Katdaddy]

Another interesting Winter day ahead for SE TX and working from home. Safety always first and glad for the school closures. It will not take much Winter precipitation for dangerous conditions.

[Rip76]

So are we now looking at earlier than 12 noon for Houston issues?

[snowman65]

Dallas just exploded in the last 2 hours.

[Belmer]

So are we now looking at earlier than 12 noon for Houston issues?

Freezing rain/sleet should begin to arrive in Harris Co. and much of SETX between 5-8AM. That will continue into the late morning hours. As the air column cools, the backside of the precipitation should switch over to snow as it wraps up, but it will all be about timing. Dry air could filter in faster and cut off that snow chance.

[sau27]

So are we now looking at earlier than 12 noon for Houston issues?

Yes, looks like some wintry mix could start by 8 or 9 am in Houston.

[Rip76]

Thank you.
I will pass this on to my drivers.

[Andrew]

Dallas just exploded in the last 2 hours.

They just changed radar scan modes to clear air mode (VCP 31). That is why it looked like it "exploded" in coverage. It's a more sensitive scan mode. Still seeing some light snow showers though.

[DoctorMu]

The front just barreled through College Station. 10° temp falloff in just a few minutes. On its way fast to Houston. Blowing cold rain begins.

[Ptarmigan]

Code: Select all

926
FXUS64 KHGX 160306
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
906 PM CST Mon Jan 15 2018

.UPDATE...
Evening surface analysis showed a cold front stretching from
Temple to Palestine, with temperatures in the D/FW Metroplex
having already falling to freezing behind the front. Simple
extrapolation of the latest frontal movement places the front into
College Station by 9:30 PM, Houston by 12 AM, and Galveston by 2
AM. With surface pressure rises behind the front having increased
over the past few hours, have very little reason to think the cold
front will slow down at all and have lowered overnight
temperatures and temperatures during the day Tuesday 2-3 degrees
as a result. A late evening update may be required should this
faster trend continue. Have also added a mention of rain/freezing
rain/sleet into Burleson, Brazos, Madison, and Houston beginning
after midnight to account for these colder temperature trends as
light to moderate rain in the vicinity of the front gradually
transitions as the layer of cold air behind it deepens. Did not
make any changes to the ongoing Winter Storm Warning or Winter
Weather Advisory with this addition as surface temperatures will
be too warm for impacts to begin before 3 AM CST.

Winds will quickly become northerly and gusty behind frontal
passage, remaining elevated through the day Tuesday. These winds
are expected to be strong enough to produce wind chills in the
single digits to teens at times Tuesday morning. Have opted to
include this hazard in the ongoing Winter Storm Warning instead of
issuing a separate Wind Chill Advisory to keep hazard
communication as simple as possible during a complicated event.

Intermittent periods of sleet, freezing rain, and even snow will
spread south through the day Tuesday, reaching the Houston metro
after sunrise and the coast after noon. Continual precipitation is
not expected through the day... but moreso several 2-4 hour
periods where precipitation occurs as waves of frontogenetic
forcing moving across the region keep the atmosphere primed to
produce winter weather. Colder temperatures during the day Tuesday
will only help encourage the potential for ice accumulations.

Huffman

&&

Latest forecast discussion from NWS Houston.
http://forecast.weather.gov/product.php ... glossary=1

Cold front could arrive as early as midnight.

[Andrew]

Based on latest model data I think it is becoming more and more likely this will be a freezing rain with some sleet event. A lot of the mesoscale models indicate that inside the Houston Metro the warm nose will remain for most of the day. If snow does occur at all it probably won't be for the last part of the event and even then it will be a very wet snow. I'm worried about travel for all of SE Texas tomorrow evening into Wednesday morning as temps drop into the lower 20s and upper teens.

[don]

The latest HRRR qpf is interesting

[Rip76]

So my drivers should be able to run deliveries in the first part of the day, and sketchy after noon?

In Houston.

[Belmer]

So my drivers should be able to run deliveries in the first part of the day, and sketchy after noon?

In Houston.

I would say that is your call as a business standpoint and how urgent those deliveries are. I've always had the advice to others (friends/family) that you can trust yourself all you want when it comes to driving on ice/snow, but it is those around me I don't trust. Meaning your drivers could be 100% experienced driving in road conditions like ice, but I wouldn't trust a driver next to me when it comes to speed and braking.

[don]

And the Texas WRF is not backing down on the possibility of mesoscale banding

http://www.atmo.ttu.edu/bancell/real_ti ... bz_f16.gif

http://www.atmo.ttu.edu/bancell/real_ti ... bz_f17.gif

[Andrew]

And the Texas WRF is not backing down on the possibility of mesoscale banding

http://www.atmo.ttu.edu/bancell/real_ti ... bz_f16.gif

http://www.atmo.ttu.edu/bancell/real_ti ... bz_f17.gif

Definitely the most aggressive model and most of it would fall as sleet/snow