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don wrote: ↑Sun Jan 10, 2021 12:59 am Models have trended a lot more to the south with the gulf low over the last 24 hours.I'm starting to feel pretty confident that there will be snow as far south as the 59 corridor tomorrow. And maybe even brief heavy snow as far south as I-10.

don wrote: ↑Sun Jan 10, 2021 12:48 am Yes! The latest HRRR is very interesting.

Area Forecast Discussion
National Weather Service Houston/Galveston TX
1043 PM CST Sat Jan 9 2021

.UPDATE...

Hi-res models continue to arrive increasingly colder/wetter in our
north, and even the globals still hint at some potentially big
numbers. Have spent this evening trying to adjust for this, but
there are still a couple concerns about the big numbers some of
the guidance is popping out.

First, while it hasn`t been terribly warm of late, I wonder how
much snow will have to be wasted in order to bring ground temps
down enough to get some solid accumulation. If we can get some
high initial snow rates, this may not be as big a concern. But if
snow is a bit slow in coming in, we will waste time and snow on
even creating a ground environment conducive to accumulation.

Additionally, because snow looks to begin this afternoon and
temperatures will be near the high end for snow at this time,
snow-liquid ratios are going to be low...real low. It`s hard to
believe those totals pushing 10 inches in a 10:1 ratio snow map
when it seems more likely to me the SLRs will be down towards 6.
(Also, 6:1 snow sounds absolutely excruciating to shovel. Hard
pass.)

So, long story short, the warning area is still looking at totals
of roughly 1-4 inches. But, there is definitely potential for
more, especially in Houston County. Adjusting for SLR, the HREF
probability-matched mean in parts of that county are more like 5-7
inches. It`s no surprise to anyone who`s spent a winter down here,
but there is a LOT of uncertainty here. Be sure to check in
frequently for the latest information tomorrow.

&&

.AVIATION [06Z TAF Issuance]...

VFR conditions continue this evening, but will begin to
deteriorate from the west around 09z. Rain has started moving
towards the TAF sites and will continue to draw near tonight.
Upper air profiles are showing a good indication of winter
precipitation as well tomorrow afternoon for the northern flying
areas. Right now, CLL/UTS/CXO have RASN in the forecast but the
situation is dynamic. Outside of that, MVFR/IFR ceilings are
expected to move in through the night. At this time, conditions
are not expected to improve until Monday morning.

don wrote: ↑Sun Jan 10, 2021 12:59 am Models have trended a lot more to the south with the gulf low over the last 24 hours.I'm starting to feel pretty confident that there will be snow as far south as the 59 corridor tomorrow. And maybe even brief heavy snow as far south as I-10.

Snakeswx wrote: ↑Sun Jan 10, 2021 5:44 am Already saw some ice snow graupel mixing with the rain here at 242 and I-45.. montgomery county

davidiowx wrote: ↑Sun Jan 10, 2021 8:00 am Nice to see the trend continues southward. Will be interesting to see where the changeover line actually sets up this afternoon!

DoctorMu wrote: ↑Sun Jan 10, 2021 8:45 am I can report heavy, heavy, heavy graupel in College Station IMBY. Potential changeover hours before expected??

srainhoutx wrote: ↑Sun Jan 10, 2021 8:10 am Sunday morning weather briefing from Jeff:

A memorable snow event likely for portions of SE TX today.

Winter Weather Advisory issued for Austin, Waller, and Montgomery Counties.

Changes overnight have been the continued south shifts of the track of the upper level low and the associated cold pocket aloft that will transition current rainfall to rain/snow mix and in some areas a complete change to all snow. With these changes, an advisory has been added to the row of counties south of the warning area for accumulations of snow of 1-2 inches this afternoon and evening. South of the advisory area across Harris County and the metro area rain/snow mix may extend to I-10 and maybe a bit south of I-10, but any accumulations are expected to be brief and mainly on elevated surface such as rooftops and grassy areas.

Travel in the warning area will become hazardous by mid to late afternoon as snowfall rates increase due to convective banding. Expect ice on bridges and overpasses and surface streets to become snow covered and slushy as snowfall rates overwhelm the warm ground temperatures resulting in accumulations. Additionally, temperatures in that area will cool toward the freezing mark increasing accumulations,

Forecast Accumulations:

NW of a line from Brenham to Huntsville to Trinity (Winter Storm Warning area):

Transition to all snow this afternoon. Widespread amounts of 1-4 inches with isolated totals of 6-8 inches possible. Hazardous travel developing and lasting into Monday morning.

NW of a line from Sealy to Cypress to The Woodlands to Porter:

Rain/snow mix this afternoon possibly transitioning to all snow this evening. Accumulations of 1-2 inches possible on elevated and grassy surfaces. Travel concerns are minimal.

South of I-10:

Mostly rain with a few flakes of snow mixed in. No travel concerns.