October 2023

[MontgomeryCoWx]

GFS is showing 30° low temps for the northern metro Houston area on Halloween. Whoa.

Going to use some voodoo to lock that in

[snowman65]

Gotta give a big shoutout, and please give a warm round of applause to our returning old friend, August.. its like you never left

[Cpv17]

I told y’all a month ago to watch for a cold snap mid to late October. Hopefully it’ll play out and prove me right!

[user:null]

So far, as of last night, only the GFS buys the more focused plunge into TX — other models (even the CMC) propogated further east, with weaker incursion into TX.

Let's see what afternoon models hold.

[Stratton20]

user:null i dont buy the CMC, that front is plowing straight into texas, its coming

[user:null]

user:null i dont buy the CMC, that front is plowing straight into texas, its coming

It's not just the CMC, both the ICON and EURO don't show anything focused on Texas (as of now). Not even the ensembles of the GFS show much (as of now).

[Cromagnum]

GFS is showing 30° low temps for the northern metro Houston area on Halloween. Whoa.

Do not want a frost that early. Grass seeds I planted to replace the death and destruction of my lawn have just gotten going for a week.

[DoctorMu]

NOAA published their winter forecast.They're expecting classic El Nino conditions this season. With above normal rainfall across the south. And near normal temps.

So a better than normal chance for some wintry precip here? North of hwy 1*5 of course.....lol

El Ninos have been known to feature winter storms here.But it may be more in the form of ice instead of snow this year.As arctic air intrusions will tend to be more shallow in nature.And often undercut with warm air and tropical moisture from the Pacific .

Overrun. Yeah, we're going to see a lot of that.

Hope y'all like ice fog!

[DoctorMu]

Everyone except GFS on 12z run has moisture NW of SETX this week and Halloween. If it's going to be humid this week it might as well rain.

Temps rocketed from 57°F to 90°F+ this morning and early afternoon

[Stratton20]

12z Euro sees the front, very chilly air behind it, their is nothing better than a cold halloween, fingers crossed!

[DoctorMu]

Norma is a maybe. The Baja ULL is a maybe for rain.


Area Forecast Discussion
National Weather Service Houston/Galveston TX
1207 PM CDT Sat Oct 21 2023

...New AVIATION...

.SHORT TERM...
(Today through Sunday Night)
Issued at 316 AM CDT Sat Oct 21 2023

Starting to see some patchy fog development around the area. This
should burn off fairly quickly after sunrise. Surface high pressure
situated in the wcntl Gulf will maintain a dry/hot ssw low level
flow across the area today. Readings could again flirt with records
in the 90s at many locations assuming increasing high cloud
cover doesn`t moderate things too much.

SREF is fairly bullish with probabilities of fog & lower
visibilities across inland portions of the region tonight. That
said, forecast soundings also generally favor the cirrus deck
thickening aloft. Depending on if/when this occurs should play a
role in the overall coverage of fog and/or visibilities.

Low level ridging trends further eastward by Sunday allowing for a
more prevalent s/se flow off the Gulf to set up. With increasing
moisture and cloud cover, look for daytime highs to peak in the 80s.
Still a bit too dry for rain chances during the day, but should see
some isolated-scattered rain chances late Sunday night as a surge of
1.5-2.0" PW`s make their way toward the coast west of I-45. 47

&&

.LONG TERM...
(Monday through Friday)
Issued at 316 AM CDT Sat Oct 21 2023

An upper-level trough and associated moisture from the remnants
of Norma will be moving into southeast Texas Monday supporting
some scattered shower activity and perhaps a few thunderstorms,
especially west of I-45. Look for decreasing coverage by the late
afternoon and into the evening/overnight hours as the disturbance
exits off to the north.

A large upper-level low will be moving across the Baja on Tuesday
and into Wednesday, with an upper-level ridge expanding slightly
over the Gulf of Mexico. This will result in some slight height
rises over southeast Texas and decreased rain chances.
Nevertheless, moist southeasterly flow should still result in
some isolated to widely scattered showers, especially over the
western portions of the area.

There is still a large amount of uncertainty over the latter part
of the week and into the weekend regarding the eventual evolution
of the western US trough. The GFS is much more progressive and
brings most of the energy across Texas late Wednesday and into
early Thursday, with the ECMWF and CMC keeping the system cutoff
over northern Mexico. WPC cluster analysis lends a bit more weight
on the slower ECMWF/CMC solutions which was already advertised in
the previous forecast. Therefore, no major changes were made
during the Thursday through Saturday time period and I continued
to advertise daily chances of some isolated to scattered showers
as a result of continued moist southeasterly flow and WAA.

[DoctorMu]

POW is on board with a Halloween cold blast, even down to SETX.

Your mileage may vary.


https://www.youtube.com/watch?v=TihC1YRwjbU


We have mid to upper level clouds from Norma. DP is low. For now, but it won't last.

https://www.star.nesdis.noaa.gov/GOES/s ... &length=24

[Stratton20]

The GFS has several days of overunning precipitation + chilly weather, could be an interesting halloween

[user:null]

The models have gotten more lenient with the potential cold (as of now).

Whereas previously it was the GFS with the coldest overunning, the EURO is now the coldest solution and it's still quite lenient compared to the older GFS outputs. (when accounting for cold bias, the CMC is a milder solution than EURO, as the overall pattern there is more progressive, as opposed to the slower patterns that prolong overrunning).

Ensembles still not showing anything focused to Texas.

[Stratton20]

Ensembles DO bring the colder air down into texas, its just a question of how cold and where the sharp temperature gradient will be, noticeable differences between the 12z CMC and GFS, both have trended colder for our area, but the ejection of a trough and placement/ where the trough digs, models do not agree on it, that can have implications on how much cold air gets dragged down, some folks could have highs in the upper 40’s -50’s while some are stuck in the 60-70’s, pretty tough forecast ahead

[DoctorMu]

Just overrun clouds from Norma. We'll see if the Baja low can sweeten the pot.

[DoctorMu]

Higher PWs and impulse could combine for some rain tomorrow. I'm a bit skeptical.


Area Forecast Discussion
National Weather Service Houston/Galveston TX
1212 PM CDT Sun Oct 22 2023

...New AVIATION...

.SHORT TERM...
(Today through Monday Night)
Issued at 300 AM CDT Sun Oct 22 2023

Variable amounts of cirrus will be streaming overhead again today.
With low level winds trending toward a more se direction, afternoon
highs shouldn`t be quite as high as they were yesterday, but still a
good 8-10 degrees above seasonable norms. Moisture levels will be on
the rise. Though still too dry for precip across most of the area,
we`ll see a pocket of higher PW`s, seen on GOES PW imagery across
the west central Gulf, begin moving into our western waters and the
Matagorda Bay area later in the afternoon and generate some isolated
to scattered showers.

This pocket of 1.5-2.0" PW`s will continue to track northward
tonight, and combined with some weak disturbances embedded in the
upper flow, bring better chances sct precip across inland areas
tonight and Monday...highest west of the I-45 corridor. This batch
of higher PW`s will track further north on Monday...with the better
chances generally north of the US59-I69 corridor mainly in the
morning hours.

With the exception of some iso waa shra activity, looking for fairly
low POPs Monday night. With a more prevalent se flow in place,
overnight lows should remain in the 70s across the vast majority of
the area. 47

&&

.LONG TERM...
(Tuesday through Saturday)
Issued at 300 AM CDT Sun Oct 22 2023

The synoptic pattern becomes increasingly amplified on Tuesday as
a mid/upper ridge builds over the Gulf resulting in a
corresponding increase in mid/upper pressure heights across
southeast Texas. This increasingly suppressive environment coupled
with decreasing PWATs should result in much lower PoPs on
Tuesday. However, global guidance still indicates above normal
PWATs west of I-45, likely aided by increasing LL onshore flow.
Therefore, we opted to keep slight PoPs for areas west of I-45 on
Tuesday. Conditions will remain warm and humid with temperatures
generally in the mid/upper-80s.

Meanwhile, a robust mid/upper trough will dig southward over the
southwestern U.S. and northwestern Mexico on Tuesday before
lifting northeastward into West Texas on Wednesday and into the
central plains on Thursday. Though the bulk of the associated lift
will remain west and north of our region, increasing PVA along
with rising LL PWATs and increasing ML RH from both the Gulf and
tropical Pacific will bring a better chance of
showers/thunderstorms to our region on Wednesday and Thursday
(PoPs ~40-50%). These PoPs represent a slight increase compared to
the last forecast package while being slightly lower than the
general model consensus. Friday`s PoPs are a little trickier.
Guidance indicates that PWATs will remain quite high for your
Friday. However, the atmosphere may be lacking a lifting mechanism
other than your typical diurnal/mesoscale processes. We opted for
30-40 PoPs on Friday and 20-30 PoPs by Saturday.

Self

[snowman65]

Looks like next good front wont move through s.e. tx until Nov 1, just missing halloween

[Stratton20]

snowman65 give or take a day, still 7-9 days out so the timing will change a bit

[user:null]

but the ejection of a trough and placement/ where the trough digs, models do not agree on it, that can have implications on how much cold air gets dragged down

Exactly. Nothing matters until the exact movement of the PNW upper trough is ascertained.