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Tuesday morning briefing from Jeff:

Hard Freeze tonight and again on Wednesday night

Sleet falling over the area this morning…additional light sleet/snow possible this afternoon/evening…no accumulation is expected

Cold arctic air mass is firmly entrenched over the region with 800am temperatures at or below freezing across the entire region. A mid level jet streak is resulting in some weak lift over the area and there is surprisingly just enough moisture (even with dewpoints below 20) to result in the formation of sleet bands. There have been numerous reports of sleet this morning over the area. While surface temperatures are below freezing, the sleet is not heavy enough to accumulate.

Mid level energy will continue to ride across the area today and chances for light sleet/snow pellets will increase slightly this afternoon and evening especially south of I-10. Not expecting any accumulation at this time, but will have to watch for any banding enhancement that could result in a slightly heavier precipitation rate. With thick clouds today…temperatures are going nowhere fast. Expect highs to top out around the mid 30’s over much of the area and a few locations may not break the freezing mark up north.

Tonight:
Main questions tonight is when will clouds begin to clear and how cold will low temperatures fall. Models show clouds clearing by mid to late evening which should allow several hours of good radiational cooling with the arctic surface high nearby and winds going light NE. If clouds clear out as forecast a hard freeze will be likely over much of the area (25 or colder for 2 or more hours). If clouds are slower to clear, then may areas may only fall into the upper 20’s.

Sunny skies should return on Wednesday allowing a warm up into the mid 40’s. Artic surface high will begin to progress eastward and winds will become ENE/E Wednesday night. Expect another very cold night with another hard freeze possible over the region on Thursday morning below winds become onshore on the backside of the arctic high and warming begins. Warming trend will be slow but steady into the weekend…with some area near 70 by Saturday and Sunday.

Sleet pellets falling on the east end of Galveston.

Light sleet/light snow mix reported in Wallisville

Just had some light sleet in here in W League City.

Latest HRRR run wants to bring a couple hours of non-accumulating light snow to Harris County early tonight.

Make that moderate sleet now in W League City. Hearing roofs are white with sleet in Pearland.

There are some sleet pellets that have accumulated on cars here in The Heights. I think the Canadian was maybe on to something with its consistency for snow...

To bad we can't get this band to back build and fill in for the entire day! That would be epic!

davidiowx wrote:To bad we can't get this band to back build and fill in for the entire day! That would be epic!

And too bad it isn't moving in from the SW.

Radar shows snow in my area, but it's sleet / freezing rain.

Thanks to that upper trough that was over Wyoming yesterday morning we have a jet streak and some lift as it nears Texas. We will have to monitor for any banding features that cannot be predicted beyond an hour or two throughout the day into tonight. There was some minor accumulations across portions of Central Texas and that band is nearing the Highland Lakes and approaching the Austin area. We'll see if any reports of accumulation albeit minor are verified in a while.

Later this afternoon and evening is when the “main event” is suppose to happen at least according to some models, that have remained consistent on snow moving across the area later today.The Texas Tech wrf is now onboard also We will see...

I'm at my office downtown and it was a steady sleet/freezing rain from 8:30-9 just now. Maintenance workers are spraying de-icing substances on the sidewalks. My co-workers were saying 59 elevated behind the George R. Brown is very slick.

Sleet here in Alvin and a lot of it. I am in hibernation mode waiting for summer!

Looks like there is accumulations on I-45 down in the webster/friendswood area. At least it appears that way per transtar web cams. Here is an accident at Nasa Road 1

https://traffic.houstontranstar.org/cct ... IH-45_Gulf

Cmc and rgem still on board

stormlover wrote:Cmc and rgem still on board

CMC might be a bit of a stretch...but you never know...

What's with all the radar action in Killeen? Looks like something has just been sitting there all morning....

Hrrr on board now

snowman65 wrote:What's with all the radar action in Killeen? Looks like something has just been sitting there all morning....

Area Forecast Discussion
National Weather Service Fort Worth TX
1111 AM CST Tue Jan 2 2018


.MESOSCALE UPDATE...
/Bitter Cold Temps/Wind Chills/and Very Light Snow Today/

We continue to monitor a very small, mesoscale band of light snow
or snow grains, with late morning temperatures in the upper teens
along the immediate Red River Valley, to the lower-mid 20s
elsewhere. This band of light snow/snow grains will likely
continue through midday, before RAP/NAM models show this area of
pressure advection and isentropic ascent on the 285-290K surfaces
shifts east and weakens. There are signs of some small-scale
frontogenetical forcing within the 700mb-850mb layer that may
linger longer, so this small area of forcing across a 4-5 county
area across Central Texas will need to be monitored, along with
reports.

Elsewhere and further northeast, the bitter cold sub-cloud layer
is additional 1-2 kft deeper with a few flurries possible as the
shortwave approaches, but more potential for evaporation, or more
likely sublimation occurring before any light snow or snow grains
could reach the surface. Still, forcing just northeast of D/FW
looks impressive with the very dynamic shortwave tracking
southeast across the northeast counties. This leaves me with some
apprehension and concern that the sub-cloud layer could saturated
down low enough for some actual, though brief snow showers and
brief banding. For now, will monitor these trends into the
afternoon hours and see how things transpire. With the frigid
temps in place, any snow grains should be light and wind-swept,
with mainly very light accumulations on grassy areas and sides of
roadways. There could possibly be brief, but minor impacts on
elevated surfaces across Western Central Texas as traffic melts
any snow grains, then they quickly refreeze on bridges and
overpasses.

Otherwise, did update low level temperature and dew point trends,
as a reinforcing surge of very dry and cold arctic air seeps in
from the northeast with broad arctic surface ridge currently over
the Mid Mississippi Valley and Ozarks. With the aformentioned
airmass, wintry precipitation processes, cloud cover, and
continuing, but modest low level cold advection...I could not see
temperatures warming more than another 2-4 degrees(at most) into
the afternoon hours. Throw in northeast winds shifting to the
north around 10 mph and wind chills will remain in upper teens
north to the lower 20s in parts of Central Texas.