December 2022

[DoctorMu]

00z GFS has my attention now, more moisture,
hinting at precipitation with the front in SE Texas……

Yep. CMC as well, but not as much

A hint of mischief.

[DoctorMu]

The GEM keeps us below freezing from Thursday afternoon to Sunday afternoon with multiple nights in the low teens. Could it be on to something? It handled Feb 2021 better than any other model. I really wish the NAM was within range. Ugh!

We'll know more in a couple of days when the mesos have the even in their scope.

[DoctorMu]

The GEM keeps us below freezing from Thursday afternoon to Sunday afternoon with multiple nights in the low teens. Could it be on to something? It handled Feb 2021 better than any other model. I really wish the NAM was within range. Ugh!

The GEM was the closest to correct with the Feb 2021 event for CLL. We got our 5-6 inches of snow and ice.

There's our Labrador saying "I'm home!" lol She was in heaven. Walks in 15°F weather were no problem for her.

[suprdav2]

Enjoy your trip & Happy Anniversary suprdav2!

Thanks!! Will do!!

[Cpv17]

6z ICON has IAH down to 10°F Friday morning.

[brazoriatx]

I work in water treatment..so today we are breaking everything apart and draining pipes..ugh!

[snowman65]

Too bad the cold isnt already here for this wet mess.

[Cpv17]

6z NAM has a 1070 MB high in far NW Wyoming.

[brazoriatx]

I'm assuming that would drive the temps down a cpl more degrees

[tireman4]

In the short term.....


000
FXUS64 KHGX 191150
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
550 AM CST Mon Dec 19 2022

...New AVIATION...

.SHORT TERM...
(Today through Tuesday Night)
Issued at 433 AM CST Mon Dec 19 2022

Rain showers have started to increase in intensity and coverage
early this morning, and this is only a prelude of a rainy day.
Two main weather systems will move near southeast TX today and
tonight, resulting in widespread showers and scattered
thunderstorms. A coastal sfc low, currently over the southwestern
Gulf/South TX coast will continue to move north- northeast along
the Middle/Upper TX coast throughout the day. As the day
progresses, an upper-level shortwave trough, currently over the
Southwestern CONUS, will shift eastward across TX/Southern Plains.
As these two systems approach the region, a strengthening south
to north LLJ and isentropic ascent will increase moisture
advection across the entire region. Two axis of higher rainfall
totals will be possible; one along and off the coast and the other
roughly along and north of a line from CLL to Conroe to
Cleveland. Deep moisture along with steep low to mid- level lapse
rates and increasing intensity in frontogenesis within the 850:750
mb layer will support efficient rainfall rates over these two
areas. Rainfall rates of 1-1.5 in/hr will be possible inland and
up to 2 in/hr near the coast. Rainfall totals from half an inch to
2.5 inches are expected, localized higher amounts possible.

Precipitation should begin to taper off from south to north by
early this evening as forcing diminishes over the region. However,
isentropic ascent forecasts and model soundings do suggest there
will still be some weak ascent in the near-surface layer
(925:850mb), resulting in patchy drizzle rather than just
stratus/low clouds tonight.

A relatively dry and cool Tuesday is expected with light to
moderate north winds and mostly cloudy skies. Highs will only
climb into the 50s and overnight lows mainly in the 40s.

&&

.LONG TERM...
(Wednesday through Sunday)
Issued at 433 AM CST Mon Dec 19 2022

The primary focus in the long term continues to be the looming surge
of arctic air that is likely to result in prolonged freezing
conditions for much of our CWA. The approaching arctic air will
still be well to our north on Wednesday. The day will feature
generally cloudy albeit benign conditions with highs mostly in the
mid/upper 50s after morning temps in the 40s. After Wednesday, our
attention shifts to the aforementioned arctic air.

On Thursday, the arctic front will be approaching SE Texas from the
north. Global deterministic guidance generally suggest a frontal
passage during the afternoon hours for our northern/Brazos Valley
counties, around sunset for the city of Houston, and then offshore a
couple hours thereafter. That being said, variance in the exact
frontal passage timing still exists among the guidance. EC continues
to be somewhat faster than the GFS. It is not uncommon for global
models to underestimate the forward speed of dense, advancing,
arctic air masses. Therefore, our afternoon highs on Thursday skew a
little cooler than the model consensus suggest to account for this
possibility. However, the bust potential in Thursday`s temperature
forecast remains quite high due to timing uncertainty as well as
model discrepancies regarding the amount of WAA ahead of the arctic
front. Interestingly, the 00Z EC is actually warmer than the 00Z GFS
for the Houston metro on Thursday despite it`s earlier FROPA. The
reason is due to the more robust WAA ahead of the frontal boundary.
Despite the relatively low confidence in Thursday`s temperatures,
confidence is quite high that a hard freeze looms in the front`s
wake.

PoPs along and ahead of the front remain quite low. In fact, we have
lowered PoPs further since the previous update. Very dry air will
quickly filter into the region behind the front. Therefore, this
forecast continues to be void of wintry precip. Strong CAA Thursday
night will be felt in the form of rapidly falling temperatures and
very gusty winds. Global deterministic, ensemble, and NBM guidance
continue to have good consensus regarding a hard freeze Thursday
night into Friday morning. Forecast lows on Friday morning continue
to be in the 10s for most of the CWA. Areas near the immediate coast
are forecast to bottom out in the low 20s. Temp grids are showing
single digits in some of our farthest north spots like Crockett.
However, the biggest story Thursday night and Friday morning may be
the wind chills. Winds during this time frame could be sustained 20-
30 mph with gusts over 40 mph with higher winds possible near the
immediate coast. These winds combined with the low temperatures will
easily result in sub-zero wind chills over our northern counties.
Sub-zero wind chills could occur as far south as the Houston metro.
Single digit wind chills are expected along the coast Friday
morning.

Bright Texas sunshine may not be enough to allow for a true thaw on
Friday afternoon. Highs are expected to range from the mid-20s in
our northern counties to around freezing at the coast. This sets us
up for a freeze that could last upwards of 36 hours, perhaps longer
for our northern counties. Given this continued risk for a prolonged
hard freeze, consider the actions you will need to take to protect
the 4 "Ps" -- people, pets, plants, and pipes.

Winter`s chill will dominate the weather through the Christmas
holiday. The current outlook for Christmas Eve features more cold
sunshine with highs in the mid-30s in our northern counties,
upper- 30s in the Houston metro, and around 40 at the coast.
Christmas Day currently appears a little warmer than Christmas
Eve. But at this time, it appears the heavy jacket weather will
linger through at least Christmas Day. Perhaps we can warm into
the 50s by early next week.

Self

&&

.AVIATION...
(12Z TAF Issuance)
Issued at 541 AM CST Mon Dec 19 2022

Scattered to widespread rain with isolated thunderstorms are
expected today as different disturbances move through the region.
This will result in widespread IFR to occasional LIFR conditions
across all terminals. Expect even lower ceilings and/or visibility
with any stronger thunderstorms, especially in the afternoon
hours. Precipitation should come to an end this evening; however,
stratus along with a few spotty showers/very light drizzle will be
possible through the night. East to northeast winds will
transition to the north-northeast by this evening with the
strongest gusts near KGLS.

&&

.MARINE...
Issued at 433 AM CST Mon Dec 19 2022

Advisory level winds will persist through the day today as low
pressure moves northeast along the coast. The system will bring a
good chance of showers and thunderstorm today. Moderate offshore
winds are expected in the system`s wake on Tuesday and Wednesday.
Attention will then turn to an approaching arctic front on Thursday.
Gale conditions are expected in the front`s wake Thursday night and
Friday morning. Winds offshore could gust up to 50 knots during this
time.

Self

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 49 44 54 42 / 100 50 10 0
Houston (IAH) 51 45 56 43 / 80 50 0 0
Galveston (GLS) 62 49 56 48 / 90 40 10 10

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...Small Craft Advisory until 6 PM CST this evening for GMZ330-335-
350-355-370-375.

&&

$$

SHORT TERM...JM
LONG TERM....Self
AVIATION...JM
MARINE...Self

[Cpv17]

Looks like most of todays rains will be in the far northern parts of the viewing area and into Central/Northern LA where it’ll be a complete washout. Looks like just scattered showers and a couple small thunderstorms for most of us today.

[tireman4]

Saw lightning ( one time) on my way to work from Humble to the Gulfgate area. Areas near the coast are quite blustery.

[davidiowx]

Looks like most of todays rains will be in the far northern parts of the viewing area and into Central/Northern LA where it’ll be a complete washout. Looks like just scattered showers and a couple small thunderstorms for most of us today.

There should be some developing to our SW that will move through the area today. Think we will all get some rain, not a complete washout though.

[Cromagnum]

Nearly finished my wooden box around my outdoor water softener unit. Hopefully the rains lay off so I can complete the job today.

Just saw where the Thursday high is supposed to be mid 60s before dropping 50 degrees. My sinuses will love that. I'm not seeing any indication whatsoever of precipitation though, so this event is wasted.

[Stormlover2020]

I would rather 105 degrees, unless we get snow and that’s not happening lol

[Stratton20]

This event is not wasted, their was never really much in the way of support for snow to begin with outside of that lala land gfs run

[jasons2k]

Well the infrared turkey fryer will be working overtime this Christmas. Usually, I would be enjoying some pleasant weather outside shooting the ‘stuff’ with family over a few cold ones. This year we’ll all be inside by the fire. I did a recent poll and none of my family in the area is looking forward to the cold weather. Without any snow, it’s just a nuisance. A total waste. It will be cold enough to drain the pipes and shut the water. Some people unfortunately are going to have a plumbing mess with busted pipes right before Christmas. With the wind my garden will be toast. Again. It was just starting to recover nicely from snowmageddon too.

[Cpv17]

This event is not wasted, their was never really much in the way of support for snow to begin with outside of that lala land gfs run

A lot of people on here don’t like cold weather without snow. Me on the other hand, I like extremes so I’m fine with the colder temps. I understand where people are coming from though by saying this cold blast will be wasted because of no snow. I think we’ll have a better chance for something later this winter. Largely going to depend on what the EPO does. AO and NAO I’m not too concerned about.

[sambucol]

I’m liking the cold with or without snow.

[tireman4]

From Jeff...

Arctic Air Event:
Impressive arctic high pressure system over NW Canada will move SSE toward the Montana border and then into the US over the next 24-48 hours. Surface pressures in the 1055-1060mb range will be positioned just north of the Montana border by tomorrow and Tuesday and then dump southward into the high plains. Very cold and dense arctic air mass will be unleashed down the plains and arrive into N TX late Wednesday and off the TX coast by Thursday evening.

Will continue to side with the fastest of the guidance on the arrival of the arctic front with mid afternoon most likely across SE TX….this may need to be sped up some as these types of air masses tend to move south faster than expected given their extreme density. Temperatures will warm into the 60’s ahead of this front and then the bottom is going to fall out with temperatures falling 20-30 degrees in a few hours post front and howling north winds. Freeze line will quickly advance into the region Thursday early evening and all the way to the coast by midnight. Impressive cold air advection will be in place with north winds of 25-30mph and gust of 40-45mph across the region. This will result in wind chills falling into the 10’s and 1’s over the entire region by late evening Thursday. I cannot stress enough how abrupt this change will be Thursday evening. Wind chills by Friday AM may fall below 0 for areas north of I-10…wind chill advisories/warnings will almost certainly be required along with hard freeze warnings and likely a wind advisory and gale warning for the Gulf waters.

Strong cold air advection will drive temperatures well below freezing for the entire area by late evening Thursday and below hard freeze criteria by Friday morning (24 or lower for 2 hours or longer). Have trended lows a bit colder into the upper 10’s/near 20 to the coast, mid 10’s to I-10 and low 10’s north of HWY 105. Temperatures of this magnitude will be capable of causing damage to unprotected infrastructure and vegetation.

Cold arctic high sinks into Texas on Friday and temperatures will only rebound to near freezing for most areas…many areas will likely remain in the 20’s for much of the day and then another hard freeze for much of the area Friday night/Sat AM.

No precipitation is expected with this cold air event and there will NOT be any travel related concerns on roadways. However, it should be understood that a lack of snow/ice does not reduce the threat of the potentially damaging impacts of the cold air

Duration:
Many areas north of I-10 will likely experience 30-40 hours below freezing from late Thursday through midday Saturday. Areas south of I-10 have a slightly better chance or reaching 32-34 Friday afternoon, but this may be optimistic and many of those areas may also stay below freezing for an extended period of time as well.

Preparations:
Maximum cold weather actions will be needed for this upcoming cold air outbreak to help mitigate property damage. Additionally, with wind chills falling to dangerous levels, it will be important to limit outdoor exposure as much as possible. All preparations for this cold air outbreak should be completed by Thursday midday.

Proper winterization of any exposed pipes/plumbing will be needed to prevent damage. Sprinkler systems must be shut off and properly drained. If leaving out of town for the upcoming holidays, shut off the main water supply and drain pipes to prevent damage should they burst. Pipes/plumbing on elevated homes must be protected from the ground to the entry point of the structure.

Pets/livestock will require proper shelter to protect from the cold temperatures and dangerous wind chills. Prolonged exposure to the forecasted temperatures and wind may be fatal to unprotected livestock and pets. Monitor water sources as typical sources may freeze over.

Tropical plants/vegetation will require maximum freeze protection. Unprotected tropical vegetation will be killed and even protect vegetation will likely suffer heavy damage given the advective nature of the freeze and reduction is usefulness of the “greenhouse effect” of covering sensitive vegetation.

Persons should limit outdoor exposure during the cold as wind chills will fall to dangerous levels. Utilize heating sources properly to reduce the risk of fire and carbon monoxide poisoning.