January 2017 -Warming Trend To End The Month

[snowman65]

LOL...the 12Z ECMWF suggests sub -20's at 850mb over SE Texas.

LOL....I think it's been taking some of that flakka drug.....gone crazy!

[DoctorMu]

LOL...the 12Z ECMWF suggests sub -20's at 850mb over SE Texas.

Interesting. GFS has Lucy teasing Charlie Brown with the football, with frozen stuff reaching a line between Hearne and BCS.



Euro and ensembles setting up the football...





The legend of the AggieDome. Snow doesn't make it past Hearne. Neither do cold fronts in the summer or tornadoes in the Spring (usually). The seabreeze usually falls apart around Navasota.

We'll see...but accumulating evidence of a Southern snowstorm 9 days out.

[don]

fwiw the ECMWF shows some frozen precipitation in Southeast Texas as the brunt of the cold air arrives. It also has lows getting down into the mid to low 20s across the area.

[DoctorMu]

LOL...the 12Z ECMWF suggests sub -20's at 850mb over SE Texas.

LOL....I think it's been taking some of that flakka drug.....gone crazy!

550 mb is cold as well...trying not to get my hopes up...

[cperk]

srainhoutx you think we have a shot at any wintry weather in our neck of the woods.

If anyone could actually forecast with that kind of specifics across our geographical area 9 to 10 days out, they are far better than I am...or making a lucky guess. Just too many variables at this range to accurately predict. Odds are always against us down here as we all know.

Sorry i put you on the spot.

[StormOne]

I came here to mention the 12z Euro but saw Srain beat me to it. It'd be remarkable if it verifies. Too bad (or good) it likely won't.

EDIT: I use the word "likely" very, very lightly. It's been 3 years I believe since the last hard freeze in SE TX. Maybe it's time. For now, it is way too far out to forecast specifics. The only one who can forecast well this far out is A.V.

[srainhoutx]

srainhoutx you think we have a shot at any wintry weather in our neck of the woods.

If anyone could actually forecast with that kind of specifics across our geographical area 9 to 10 days out, they are far better than I am...or making a lucky guess. Just too many variables at this range to accurately predict. Odds are always against us down here as we all know.

Sorry i put you on the spot.

It's all good. You never know. Perhaps the Parallel GFS will verify...

[srainhoutx]

I believe it's going to get mighty chilly around these parts.

[mcheer23]

I see channel 11-13 went conservative with Thursdays high. They went with 50.

[Portastorm]

Interesting comments this afternoon out of the NWS office in New Braunfels, re: next week, precip types, etc.:

On Wednesday, things will begin to quickly change as arctic air
once again pours into the southern plains. This has been a pretty
typical La Nina winter so far for South-Central Texas with many
days seeing above normal temperatures and a couple snaps of cold
arctic air which is what looks to happen again for the middle to
late period of next week. The upper air pattern for Tuesday and
Wednesday will show a very amplified and wide ridge of high
pressure off the western CONUS extending up to near 70 degrees
latitude and a deep low to the east of the ridge centered near the
4 corners region. This upper air pattern is very favorable for
arctic intrusions and we should begin to see the colder air
arrive to the region by Wednesday morning. Things could get close
to being problematic as the upper low over the 4 corners begins to
move east and synoptic lift overruns the cold arctic airmass
Thursday into Friday which should lead to precipitation production.
Because we are so far out, there are many run to run differences
and even large variability within each run`s different ensemble
members regarding the exact timing of the best chances of
and how cold temperatures will actually get. Although this
pattern is favorable for at least the chance of some wintry
precipitation somewhere in the CWA, one should not look at a
particular model solution as truth but study the many available
runs in the suite of guidance and overall trends as these
solutions are likely to change from run to run over the next
several days.

[StormOne]

Although this
pattern is favorable for at least the chance of some wintry
precipitation somewhere in the CWA, one should not look at a
particular model solution as truth but study the many available
runs in the suite of guidance and overall trends as these
solutions are likely to change from run to run over the next
several days.

Very good thing for them to say. And Winter storm systems, or any storm system for that matter, is near impossible to forecast until it gets close, or is already happening. In Lincoln back in early December, snowmageddon on 12/7 was looking likely, but with time, the models quit showing that storm. While we were all worried about the snowstorm that never happened, A light snow chance suddenly popped up on NAM, GFS, and Euro all at the same time on their 12Z runs for Saturday. We ended up getting 3" of snow on Saturday 12/3. So models are unreliable, and nobody should look at one run and say "GUYS, A(N) *Insert type of weather event that people get excited about* IS COMING," especially 9 days out. Should definitely be looked at, and not saying it won't happen. Something to keep everyone's eyes on, for sure. I would like to thank Srain and the rest of the mets on here for keeping a forum like this alive. Like I said when I left Houston in August (I'm on a plane back now btw), every city deserves a forum like this.

[StormOne]

Case in point, 18Z GFS is dissing everyone, keeping the trough well to the North. Still too early to forecast anything for 2 weekends from now, and part of the reason most reliable weather sources don't go past 7 days.

[DoctorMu]

Case in point, 18Z GFS is dissing everyone, keeping the trough well to the North. Still too early to forecast anything for 2 weekends from now, and part of the reason most reliable weather sources don't go past 7 days.

...and it's back over the north half of Texas in the 00Z Fri. Something's afoot as the window begins to narrow. A week away, but there is potential for drama...particularly because the GEM is in agreement.



GEFS ensemble is running colder again.

[DoctorMu]

Euro also still seeing invasion...

[srainhoutx]

This morning I wanted to focus a bit on the sensible shorter term weather expected New Years Day into Monday before we turn attention to the Arctic Air and overrunning precipitation event that has garnered all the activity across most social media platforms. The pesky upper low near Baja will begin to eject East toward Texas in the semi zonal flow as yesterdays cold front moves back North as a warm front later tonight into Saturday. The return flow off the Gulf along with its higher dewpoints surge back into Texas and a couple of embedded disturbances advance East within the sub tropical jet. it appears dynamics are increasing for the potential of a couple of strong to severe storms to organize with the main threat being heavy rainfall, small hail and isolated damaging wind gusts. There may be some potential for a tornado or two to quickly spin up, but that threat appears minimal. The threat may continue Monday further East into Louisiana as the Pacific disturbance shifts toward the Mid Mississippi Valley Region.

[srainhoutx]

Looking toward the mid to late next week timeframe, the overnight Day 8+ NCEP Ensembles suggest very chilly Arctic air will be established across much of North America with a very cold upper trough anchored from the West Coast to the I-95 Corridor of the East Coast. There continues to be indications of overrunning precipitation spreading over the shallow Arctic air at the surface, particularly during the next Thursday into early next Saturday timeframe. It is way too soon to know with any certainty what our temperature profiles both at the surface and aloft will be as well as whether there will be one or two embedded disturbances riding both the Northern and Southern jet streams at the time that the coldest air is in place. Typically we cannot know with any certainty beyond 3 days what our sensible weather will be particularly when it comes to p-types. That is why the Weather Prediction Center does not issue their forecasts beyond Days 1,2 and 3. Certainly we have a lot of attention focused across most Weather Boards and social media venues about this Arctic Outbreak potential and rightly so. Rest assured we will be monitoring the trends daily and pass along the "finer" details as we get closers. Stay Tuned!

[redneckweather]

Looks like a crappy, cold and wet period come next week with maybe a possible chance of that nasty freezing drizzle in the central, northwest and northern areas of Southeast Texas late next week. A good time to stay inside and do nothing. Come on mid 80's, sunshine and flip flop weather!!

[srainhoutx]

Friday morning briefing from Jeff:

2016 will end wet and warm.

Heavy rains possible Saturday SE of a line from Palacios to Sugar Land to Liberty.

Storm system off the southern CA coast this morning with SW flow aloft and sub tropical jet stream positioned over SE TX this morning. This has resulted in mid and upper level moisture spilling across the surface cool air mass resulting in widespread cloud cover. Area radars do show returns approaching from the west, but a fairly dry sub cloud layer currently is resulting in much of this mid level based rainfall evaporating before reaching the ground. Surface high which brought the strong winds and much cooler weather (compared to the recent days) is pushing eastward and surface winds will swing around to the SE this afternoon and evening and start to moisten the sub cloud layer. Disturbances embedded in the SW flow aloft will bring lift across the area from this evening through Saturday afternoon. Showers and even some thunderstorms will possible from late tonight through much of the morning hours on Saturday before ending from west to east Saturday afternoon. Meso scale guidance shows a corridor of deeper moisture roughly along US 59 Saturday morning and shows some decent convection along with higher rainfall rates of 1-3 inches. Will focus the highest rainfall totals across Liberty, Harris, Chambers, and Galveston Counties for this initial event. Will need to keep an eye for any sustained cell training over those counties as moisture levels of 1.5-2.0 inches of PW for late December is very impressive and if organized heavy rainfall develops totals could quickly add up.

Much of the rain should be over by early Saturday evening with some continued spotty light rain, drizzle, and fog for NYE. Much of Sunday will also be fairly dry with a few scattered showers developing late in the day and temperatures warm and muggy.

Sunday Night/Monday AM:
A strong upper level system combined with a Pacific cold front will move across the region. Lift and moisture will be plentiful and latest guidance suggest even instability will be enough for scattered strong to isolated severe thunderstorms. Still some difference on just how much instability will be available and where the maximum lift will reside. Some of the guidance brings the maximum lift from the Hill Country toward the Red River while others bring it from SC TX across SE TX. The second solution will bring greater severe chances across SE TX Sunday night into Monday morning. Could also see heavy rainfall again during this period, but storm motions look fairly fast and this should help to mitigate any issues.

Monday-Tuesday:
Passage of the Pacific front early Monday will usher in westerly winds and a much drier air mass. Will continue will well above normal temperatures post front as west winds and dry air will warm well into the 70’s both days. This all ends on Wednesday as the next arctic air mass gathering in NW Canada moves down the plains and arrives into TX.

Wednesday-next weekend:
Upper level pattern across much of the US will undergo amplification with strong ridging developing well into Alaska and also across Greenland resulting in high latitude blocking with a trough across much of the US. Cold arctic air mass will be gathering in NW Canada and begin to move southward into the Rockies by early next week. Position of the trough developing across the US is not overly favorable for arctic air to blast southward, but instead ooze south under its own density with fairly zonal flow across much of the US. Arctic front should arrive across TX on Wednesday and surge off the TX coast late Wednesday with temperatures falling quickly behind the front on Wednesday into the 40’s and 50’s. This pattern also favors a low latitude storm track where moisture overruns the surface cold air and can lead to southern plains and southern US winter weather events.

Questions then turn to just how cold will this air mass be and when/how much precipitation falls in the post frontal cold air Thursday and Friday. At this point there are many questions regarding the depth of the cold air, how cold the surface layer is, is the air mass too dry to support precipitation, and if in fact precipitation does occur in what form which depends on the surface and mid level temperature profiles.

At this point will go with temperatures in the upper 30’s and low 40’s on Thursday with “liquid” rain for all areas of SE TX…Thursday night into Friday morning looks to be a critical time period where surface temperatures may fall into the low to mid 30’s and rain continues. For now will keep everything liquid over SE TX, but should future model runs lower surface temperatures any more would need to think about some freezing rain potential in our NW counties Friday morning.

[srainhoutx]

Look for volatility in the various computer scheme ahead as the Hemispheric Pattern changes...

Ryan Maue ‏@RyanMaue · 60m60 minutes ago
Forecasts of 10 day lower stratosphere seem to be trending toward extreme height falls over Canada heading south.

[Portastorm]

As usual, a lot of great information here. Thanks srainhoutx!