December 2018: Sunshine Returns New Years Eve

[CRASHWX]

Srain...do you see connections to 66 / 76 / 77 as far as cold invasion?

Analogs are a great tool when inspecting what a long range patterns may bring, but there are far more moving parts in the Hemispheric Pattern that will determine what our sensible weather may bring. MJO is a big factor and any Westerly wind burst that could develop as well as the rather well advertised Sudden Stratospheric Warming and potential of very high altitude wind reversal that may totally break down the Polar Vortex. That said there are growing indications the various Hemispheric Teleconnection Indices will be more favorable for delivering cold air much further South into North America later this month into January. I will say that many a heart of the Winter Weather lover has been broken by the various computer model schemes predicting cold and winter weather that end up somewhere else, so caution is advised...

Thanks for your take Sir!

[Cpv17]

The CMC, FV3, & GFS all look very wet for next week starting around Wednesday/Thursday and lasting through Saturday. Euro not really on board yet though.

[TexasMetBlake]

Anybody else paying attention to Friday morning? The GFS has been very persistent in a deep, cold upper-level low passing through north central Texas. I know the profiles are marginal here but I’m beginning to think that snowflakes, maybe a light snow shower may be possible around the region very early Friday, maybe a dusting on the grass in north Texas.

The low just has a “look” about it that seems funny to me. I’m not exactly sure how this compares to the mid November snow event here because I don’t remember what the soundings looked like but with notable dry air we could get enough wet-bulbling, especially closer to the low where lift will be strongest to squeeze out some wintry precipitation. I’ll be watching the NAM and HRRR closely as they were the first and to my knowledge the only models that picked up on the mod november event.

[Cpv17]

Can someone throughly explain to me why this coming system will be producing such strong winds? I’m eager to learn as much about the weather as I can.

[srainhoutx]

Can someone throughly explain to me why this coming system will be producing such strong winds? I’m eager to learn as much about the weather as I can.

Very strong jet stream winds at 250mb plus dynamics at lower levels where we live as this very compact bowling ball upper low closes of over Texas. These very compact bowling ball upper lows attached to the Northern branch of the Polar jet stream are typically a challenge and often bring surprises as they generate very cold air aloft that can work their way to the surface. Think of it as winds rushing down a mountain into a valley of very low pressure.

[Cpv17]

Look at the strength of this bad boy. Man, someone is gonna get hammered with blizzard like conditions.

[CRASHWX]

Was it not Dec 2008 that strong closed off cut of low came across the area and with temps in the 49 degree range and snow the temp wetbulbes down to 32-34 degrees and left 3 to 5 inches? Or do I have it wrong? I’m probably wrong lol!

[Cpv17]

Was it not Dec 2008 that strong closed off cut of low came across the area and with temps in the 49 degree range and snow the temp wetbulbes down to 32-34 degrees and left 3 to 5 inches? Or do I have it wrong? I’m probably wrong lol!

I remember it snowing in Dec of 09. Had about 2” here in Wharton.

[don]

The Texas WRF brings wrap around moisture into southeast Texas fwiw. And yes On December 10th 2008 there was a surprise snow event due to a cold core low. This upcoming event looks similar to the 2008 event except this low looks much more potent than the low from 2008. Here is a picture I took that day:


(There was also a snow event the following year on December 4th 2009) pic:

[CRASHWX]

The Texas WRF brings wrap around moisture into southeast Texas fwiw. And yes On December 10th 2008 there was a surprise snow event due to a cold core low. This upcoming event looks similar to the 2008 event except this low looks much more potent than the low from 2008. Here is a picture I took that day:


(There was also a snow event the following year on December 4th 2009) pic:

Yes I sure thought that was the the event...and never know weather does repeat itself!

[CRASHWX]

BINGO

[Katdaddy]

Showers and thunderstorms will increase late this afternoon as an upper level low and cold front approach SE TX. Some locally heavy rain and a few strong to severe thunderstorms mainly E of I-45 overnight. Showers and thunderstorms will push away from SE TX tomorrow however a tight pressure gradient will result in strong winds Thursday night and Friday with sustained winds of 25-30MPH with gusts to 40MPH. Make sure your outside Christmas decorations are anchored well before winds gusting to tropical storm force arrive Thursday night.

[Texaspirate11]

Anybody else paying attention to Friday morning? The GFS has been very persistent in a deep, cold upper-level low passing through north central Texas. I know the profiles are marginal here but I’m beginning to think that snowflakes, maybe a light snow shower may be possible around the region very early Friday, maybe a dusting on the grass in north Texas.

The low just has a “look” about it that seems funny to me. I’m not exactly sure how this compares to the mid November snow event here because I don’t remember what the soundings looked like but with notable dry air we could get enough wet-bulbling, especially closer to the low where lift will be strongest to squeeze out some wintry precipitation. I’ll be watching the NAM and HRRR closely as they were the first and to my knowledge the only models that picked up on the mod november event.

Maybe North and NW of us - College Station to conroe - but I'll be mighty surprised if it reaches the galveston bay area.

[don]

Several of the global and mesoscale models trended further south overnight with the cold core low. Most of them now bring the system over southeast Texas with wrap around moisture. The system being so potent could have more dynamic cooling than what the models show, a fly in the ointment is surface temps but if we can get some wet bulbing that could help. While I wouldn't feel confident putting snow in the forecast, I wouldn't rule it out either as these types of systems can have surprises.

[snowman65]

Several of the global and mesoscale models trended further south overnight with the cold core low. Most of them now bring the system over southeast Texas with wrap around moisture. The system being so potent could have more dynamic cooling than what the models show, a fly in the ointment is surface temps but if we can get some wet bulbing that could help. While I wouldn't feel confident putting snow in the forecast, I wouldn't rule it out either as these types of systems can have surprises.

What kind of travel impacts could this have Friday? My daughter is traveling from Austin to C.S. Friday.

[don]

I wouldn't worry about it right now even if there is some snow it shouldn't accumulate on roads due to warm ground temps.

[Andrew]

Latest from Jeff:

Another highly dynamic storm system heading for the area.

Brief heavy rainfall and very strong winds likely.

Active weather event likely late tonight-Friday with multiple impacts across the state. Surface low pressure will rapidly develop today in response to the approach of a strong upper/mid level low out of the NW US. Southerly flow overnight has already begun to return moisture to the region and expect this increase in moisture to continue today. Lift will gradually increase today into tonight and a weak cool front/dryline feature will move across the area early Thursday morning (100am-800am). This feature will likely produce a line of thunderstorms with brief heavy rainfall of 1-2 inches likely. Fast movement of the line should preclude any significant flooding concerns, but some ponding on roadways will be possible during the morning commute on Thursday. Expected rainfall should not have any significant changes to ongoing river flooding over the area given the expected low totals and fairly small spatial coverage of this event. May see a brief rise on the West Fork of the San Jacinto River given the flashly nature of Spring and Cypress Creek drainage.

Approach of the strong upper level system on Thursday will help to rapidly deepen the surface low over TX and greatly tighten the pressure gradient. A powerful low level jet will develop on the backside of the surface low pressure system over eastern TX allowing very strong NW winds to spread out of WC TX into much of the state during the afternoon hours. Sustained winds of 25-35mph are likely with frequent gust to 40-45mph especially west of a line from College Station to Bay City and then along the coast. Solid gale conditions are expected across the coastal waters and area near the coastal bend could see storm force conditions with frequent gusts over 50kts over those waters. Winds will howl Thursday night with the pressure gradient remaining tight before starting to weaken by Friday afternoon. Sporadic power outages can be expected with these kind of winds along with disruptions to aviation travel at the various airports.

Thursday night/Friday morning:
Dynamic core of the upper level low will move just north of SE TX will additional lift being generated. Air mass looks to be fairly dry in the low levels as strong NW winds scour out the moisture. Strong cold air advection will drive temperatures into the 40’s by Friday morning with wind chills well into the 30’s with the strong winds. A mixture of light snow/rain will be moving from C TX toward SE TX Friday morning in association with the cold core upper level low. Think most of this precipitation will weaken and fall apart before arriving into SE TX, but cannot rule out some flurries or sleet north of a Columbus to Hempstead to Livingston line Friday morning. With surface temperatures remaining well above freezing…anything that falls will result in NO impacts.

Marine:
Extremely hazardous marine conditions will be developing on Thursday and lasting in Friday. Gale watch is up for all waters including Matagorda and Galveston Bays and expecting sustained winds of 30-35kts with frequent gusts of 40-45kts over the upper TX coastal waters and even the inland bays. Winds may be a bit higher toward Matagorda Bay and offshore the coastal bend with gust over 50kts. Seas will builds 12-14 feet quickly offshore Thursday night and 6-7 feet in the inland bays. Visibility will reduce offshore in blowing sea spray. Small craft should remain in port Thursday into Friday. Winds will gradually weaken on Friday as the pressure gradient slackens.

Strong offshore flow will drive water level below normal and a Low Water Advisory will be in place Thursday night and Friday as winds push water out of the inland bays. Looking at tides falling 2-3 feet below normal in the Ship Channel and NW sections of Galveston and Matagorda Bays which will produce hazardous marine travel for vessels and increase the risks for groundings.

[Andrew]

Several of the global and mesoscale models trended further south overnight with the cold core low. Most of them now bring the system over southeast Texas with wrap around moisture. The system being so potent could have more dynamic cooling than what the models show, a fly in the ointment is surface temps but if we can get some wet bulbing that could help. While I wouldn't feel confident putting snow in the forecast, I wouldn't rule it out either as these types of systems can have surprises.

What kind of travel impacts could this have Friday? My daughter is traveling from Austin to C.S. Friday.

There will be no impacts across SE Texas. Even Austin should be good.

[harp]

Well, that ULL didn't pan out on this run....

[sau27]

I'm out in Fredericksburg for the next 2 nights. The 12z NAM really hammered that area with some snow, but the GFS and EURO don't seem to be so convinced. If it gets close enough I plan on chasing and will post photos here if I catch anything.