Sunday, December 17, 2017

Dec. 16 17

West Houston, TX, during the mid-afternoon.
Northwest Houston, TX, during the mid-afternoon.
Houston, TX radar, during the late afternoon.
Northwest Houston, TX, during the late evening.
Northwest Houston, TX, during the early night.


Locations: Northwest and west Houston, TX.


Thoughts: The rain looked to have started sometime during the evening and maybe continued on through the late night. It was really windy, cold, and very wet, during the night. I am still not feeling that well and am in need of some good sleep, until I can feel well enough to write a full weather report.


Area Forecast Discussion 
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000
FXUS64 KHGX 170218
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
818 PM CST Sat Dec 16 2017

.UPDATE...
As of 8 PM local time, looks like the center of the low is inland
over Matagorda County with storms right near the center starting
to get their act together. Dewpoints right out ahead of this
feature at Bay City have climbed to 60 degrees, with 68 degree
dewpoints just offshore. Strong inflow is also occurring, with the KHGX
VAD wind profile showing 50 knot SE winds at 3,000 feet. Could
still see some isolated tornadoes along the coastal counties with
this system over the next few hours. Gusty winds are also
possible, and we`ve already had some 20-30kt gusts measured across
the coastal counties in the inflow region and right on the
backside of the surface low. These storms are moving pretty
quickly, so the severe threat should be over with for our area by
around midnight.

11


&&

.PREV DISCUSSION... /ISSUED 547 PM CST Sat Dec 16 2017/

AVIATION [00Z TAF Issuance]...

Yesterday we knew the next 6 to 9 hours will be a messy aviation
forecast and it looks like the forecast is on track with that
scenario. Surface analysis has a coastal low pressure forming off
the middle Texas coast with a warm front extending east just off
the Upper Texas Coast. Upper level trough remains west of the area
with water vapor imagery showing a strong vorticity max moving
out of Mexico in south Texas with the main upper low centered over
west central Texas. Over the next 6 hours we expect ceilings to
continue to decrease into MVFR and then IFR categories from
02-05Z. This also corresponds to when showers and thunderstorms
will be most numerous. Thunderstorm activity may be confined to
KLBX and KGLS but cannot rule out elevated thunderstorms for the
Houston metro terminals. KCLL/KUTS/KCXO can expect a broad area of
moderate rain for much of the next 6 hours. System should move
east out of the area 06-07Z but low ceilings and visibility may
remain. Model guidance keeps low ceilings in place for much of
Sunday morning with improvement by afternoon. With wet grounds,
light winds and a cool airmass, this seems reasonable. Look for
TAF amendments based on convection through the next 6 hours to
convey the latest timing.

Overpeck

PREV DISCUSSION /Issued 401 PM CST Sat Dec 16 2017/...

A complicated forecast continues to unfold for Southeast Texas as
a series of upper level disturbances cross Texas over the next
week. The first disturbance is noted on afternoon water vapor
imagery lifting across Southwest Texas from Mexico, with a coastal
low having developed in response near the Texas Coastal Bend.
Little has changed in the forecast thinking through tonight
regarding the evolution of this feature, with the surface low
lifting up the coast towards Matagorda Bay and then into the
Sabine Pass tonight. Light to moderate rain across the northern
counties this afternoon will spread south towards the coast in
response to enhanced convergence from the low this evening, with
a line of showers and thunderstorms sweeping across the region
from west to east as the parent storm system ejects towards the
Midwest.

VAD wind profilers from Corpus Christi show southeast to south
winds above 2000 feet and expect more of a northerly movement to
the surface low within the next few hours. This would begin to
shunt some of the moisture near the low into the Upper Texas coast
(dew points in the 64-68 degree range) and increase the potential
for a few surface-based thunderstorms. SPC Mesoanalysis shows 0-1
km shear values in the vicinity of this surface low have already
increased into the 20-30 knot range (more than sufficient low
level rotation to support tornado or waterspout development) and
expect an isolated tornado/waterspout potential to increase for
the coastal waters and immediate coastal areas within the next few
hours. The speed of the overall system should limit any
widespread flooding threat with this rainfall, but widespread rain
amounts of 1-2 inches will be possible. Expect the line of
thunderstorms to clear the region 1-2 AM with the potential for
some patchy fog development across the western counties behind the
line as the surface pressure gradient slackens.

The next system to impact the region is currently in the process
of closing off near Baja California this afternoon and will ensure
that the region maintains southwest flow aloft in the wake of
tonight`s system. Moisture behind tonight`s storm system is never
fully scoured out of the northwest Gulf and east to southeast
winds becoming reestablished on Sunday will draw this moisture
back into the region. This will mean that smaller disturbances
moving across the region in the flow aloft will result in periods
of showers and thunderstorms spreading into the region from the
Gulf beginning Sunday night. Rain chances continue through late
Tuesday into Wednesday as the Baja closed low translates eastward
and crosses Texas. This looks to drag another cold front across
the region and end rain chances for a brief period of time during
the mid-week period.

A second, stronger cold front is expected to enter the state late
Thursday into Friday. Warm air advection ahead of this front may
result in light rain spreading inland from the Gulf on Thursday,
with a combination of isentropic upglide and mid/upper level
forcing from another disturbance west of the region resulting in
periods of rain continuing into the upcoming weekend. Much colder
air is expected to move into the region behind this cold front,
with high temperatures on Friday almost 20 degrees cooler than
Thursday.

Huffman

Long Term Discussion...

Speculation continues about the forecast for the weekend before
Christmas. CIPS Extended Analogs have shown a consistent signal
for sub-freezing temperatures to reach at least parts of Southeast
Texas sometime during the December 24 through December 26
timeframe... and this increases confidence that the region will
see a spell of much below normal temperatures around Christmas.
What remains more uncertain though is when this cold air will
actually reach the region. This airmass looks to originate over
western/northwestern Canada before being dislodged southward
towards the Great Plains as a disturbance now near the Bering
Strait also dives south. These polar airmasses tend to be very
shallow by the time they reach Texas, which means that model
guidance can struggle with when the coldest temperatures arrive
behind the initial cold front. This is because the airmass behind
the front moves moreso from propagation due to density differences
at the surface than forcing from higher up in the atmosphere. The
medium range guidance that was inspected today continues to shows
signs of that struggle with the deterministic GFS/European not
bringing in sub-freezing surface temperatures until Christmas and
the Canadian, well, doesn`t bring them into the region at all.

This is further compounded by the signal that at least a weak
over-running regime sets up across the region behind the front.
This over-running, where more warm, moist air is lifted over the
colder, shallow post-frontal air, looks to produce periods of
light to moderate precipitation across the region over the weekend
before Christmas and into Christmas week. Not only is the timing
for arrival of colder temperatures in question, but whether or not
the atmosphere will be precipitating when they arrive is too.

So what do we know?
- It will be colder than normal the weekend before Christmas into
  the beginning of next week.
- Winter weather could certainly be possible... but several
  things have to come together for that to be the case.
- It is too early to determine impacts, if any.
- Model guidance is still in poor agreement on what will actually
  happen in that portion of the forecast. This makes forecast
  confidence low.
- Forecast confidence probably won`t begin to increase until the
  middle of next week when the disturbance near Alaska begins to
  dislodge our next round of colder air.

Huffman

MARINE...
A Small Craft Advisory is currently in effect across the coastal
waters and Matagorda Bay, with easterly winds sitting around 20 kts.
A SCEC is in effect for Galveston Bay until 00Z this evening, as
winds hover between 15 to 20 kts. As the coastal trough continues to
slide up the northern Texas coastline, winds in Galveston Bay will
also increase in speed, and a Small Craft Advisory will be in effect
beginning at 00Z Sunday. Wave heights will also rise and 4 to 7 feet
with this system, as it moves through the coastal waters during the
overnight hours.

Scattered to numerous showers and thunderstorms will fill in across
the waters later this afternoon into the early evening hours as the
coastal low slides north/northeast. This activity should continue
until shortly after midnight when this system shifts eastward.
Embedded in these showers and thunderstorms will be the potential
for gusty winds and isolated waterspouts through early Sunday
morning.

Wave heights will begin to lower Sunday afternoon to between 2 to 4
feet, and onshore flow will return. With winds out of the
east/southeast, warm moist air will flow over cooler shelf waters
and periods of sea fog will be possible out ahead of the next cold
front expected to push through the region early Wednesday. Light to
moderate offshore winds will prevail behind this front. This
offshore flow will not last for long though, as moderate onshore
winds will return Thursday. Towards the end of the week, the next
frontal passage is expected to reach our bays and coastal waters on
Friday afternoon. Moderate to strong offshore flow is anticipated
behind this front, resulting in elevated wave heights between 3 to 5
feet.

Hathaway

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)      45  63  52  64  60 /  90  10  10  50  70
Houston (IAH)              48  67  57  69  63 /  90  10  30  60  60
Galveston (GLS)            56  63  60  67  64 /  80  20  40  70  40

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...Small Craft Advisory until midnight CST tonight for the
     following zones: Coastal waters from Freeport to the
     Matagorda Ship Channel out 20 NM...Coastal waters from High
     Island to Freeport out 20 NM...Waters from Freeport to the
     Matagorda Ship Channel from 20 to 60 NM...Waters from High
     Island to Freeport from 20 to 60 NM.

     Small Craft Advisory until 10 PM CST this evening for the
     following zones: Galveston Bay.

&&

$$

Discussion...11

Hazardous Weather Outlook

Hazardous Weather Outlook
National Weather Service Houston/Galveston TX
750 AM CST Sat Dec 16 2017

TXZ200-213-214-235>238-171400-
Brazoria-Chambers-Galveston-Harris-Jackson-Liberty-Matagorda-
750 AM CST Sat Dec 16 2017

This hazardous weather outlook is for portions of Southeast Texas..

.DAY ONE...Today and Tonight

A storm system will move across the area late this afternoon and
tonight. On average, expect between 0.5 and 1.5 inches of rain.
Localized higher amounts are possible where any training heavier
cells occur. We will be monitoring the potential for isolated
severe storms, more specifically the threat of tornadoes, between
5 pm and 1 am. This will dependent on the eventual track of a low
pressure area moving up the coast.

With warmer air spreading over the cooler nearshore waters, areas
of sea fog may become an intermittent problem, outside of
precipitation.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

Unsettled weather, including periods of rain and sea fog, is
possible Sunday night into midweek. A much colder airmass is
expected to arrive late next week. We will be monitoring
temperatures and precipitation chances a time gets closer.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed tonight.

$$

Saturday, December 16, 2017

Dec. 15 17


Houston, TX radar, during the early morning.
Northwest Houston, TX, during the mid-morning.
The Galleria area of Houston, TX, during the early night.


Thoughts: Still needing some more sleep. It didn't rain although it looked like it was going to with all of the rain that I saw on the radar, during the early morning.


Area Forecast Discussion 
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000
FXUS64 KHGX 160311
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
911 PM CST Fri Dec 15 2017

.UPDATE...
Not much was changed from the previous forecast, just tweaked
forecast low temperatures to be better in line with the current
trends in cloud cover.

We`re still expecting a surface low pressure system to move up
the coast tomorrow, potentially bringing some severe weather to
the coastal counties. This still depends on where the center of
the low tracks, but if the coastal counties get into the warm
sector there is more than enough low level shear to get some low
topped supercells in play. The time window we`re most concerned
about this occurring is between around 5 PM and midnight. Some
models still have the low tracking just offshore, but it is worth
noting that some of the higher-res models (mainly the TX Tech
WRF) have been consistently bringing it onshore. Personally, I`m
more inclined to lean towards the onshore solution, but we`ll have
more confidence as the event gets closer and more hi-res guidance
becomes available.

Even if the low stays offshore and there is little to no severe
threat, all of SE Texas will have the potential for pockets of
heavy rainfall with this system. Nuisance street flooding will be
possible, but the system should be moving fast enough to preclude
any widespread flash flooding.

11

&&

.PREV DISCUSSION... /ISSUED 545 PM CST Fri Dec 15 2017/

AVIATION [00Z TAF Issuance]...

Quite simply looking at high and mid level clouds through the
next 12 hours with light/calm winds. The extended portion of the
TAF gets challenging as upper level trough approaches from the
west tomorrow. Showers may develop after 18Z Saturday with
lowering ceilings through the afternoon. The 21Z Saturday through
06Z Sunday time frame will be the most challenging and may see
thunderstorms develop for IAH southward in that time frame.
Ceilings will likely lower to MVFR in that time frame as
convection moves through the area. TAF ends at 00Z Sunday for all
TAFs except IAH for the 30 hour TAF which includes this timing of
convection and ceilings. The 06Z TAF update will include similar
timing for the rest of the TAFs. Timing will likely be adjusted
with 00Z model runs and future TAF updates.

Overpeck

PREV DISCUSSION /Issued 338 PM CST Fri Dec 15 2017/...

NEAR TERM [Through Tonight]...

Radar shows most showers have pushed offshore this afternoon, though
there may be some light showers or drizzle around Matagorda Bay.
However, there`s a good chance that none of these returns are even
reaching the ground. Satellite imagery shows overcast skies are
beginning to break from north to south, though perhaps too late to
allow for much more significant warming this afternoon.

Sky cover will be a fairly important consideration overnight as far
as overnight temperatures go. At this time things look open enough
for the far north to radiate down to the upper 30s to around 40,
while the immediate coastline will be hung up around or just above
50, with the rest of the area in the 40s. Rain chances look to be
quite low except for a slight chance of showers offshore growing
towards dawn.

SHORT TERM [Saturday Through Sunday Night]...

Northeast winds early look to veer towards easterly or just south of
easterly, aided by the development of a weak surface low off the
coast towards Brownsville. Look for that low to quickly scoot up the
coast Saturday night, and its precise path may become dreadfully
important for the severity of any storms in the late night hours. A
low that is able to move onshore and track just inland will allow
coastal areas to briefly enter into the warm sector - in a window
roughly from 3Z-7Z - which will help surge dewpoints above 66
degrees and create a thermodynamic situation which would allow for
storms to become surface-based. This track would also severely back
surface winds and create a situation with significant low level
shear and a very largely curved hodograph - a perfect situation for
transient, low-topped supercells with potential for tornadic
waterspouts and even some brief tornadoes very near the coast. The
Texas Tech WRF would be a prime example of this scenario.

On the other hand, a track that stays offshore, or even scrapes
right on the coastline would limit the potential intrusion of
warmer, moister air. The LLJ in this scenario would actually more
likely result in a surface layer inversion, and any thunderstorms
would become elevated and unable to tap into any low level shear.
We`d still see storms, and potentially locally heavy rain - indeed,
of the models that follow this scenario, some use convergence on the
northeast side of the quickly moving low to generate or at least
imply something like a QLCS that could have some briefly torrential
rain. On the plus side here, the dynamic wind fields involved should
keep everything moving quickly. While isolated points of street
flooding could occur, it seems unlikely that we`d see anything worse
than that as we just won`t have time for rain to pile up.

With the low clearing out quickly on Sunday, that day should
generally be quiet, though perhaps with some lingering shower
potential near the coast. But, winds will also very quickly become
onshore Sunday night, and begin to pump warmer, high moisture air
back in. Because of this, we could see the development of sea fog
overnight, and low temperatures across the area look to stay above
50 degrees.

LONG TERM [Monday Through Friday]...

As we go into next week, the closed upper low near Mexico`s Pacific
coast should start to eject, though there is some difference of
opinion as to how much interference/phasing we`ll see with the
northern jet as it does so. Beneath that low, a surface low, or at
least a trough may develop that will result in upglide from the
onshore Gulf flow and result in a new bout of showers. Monday looks
pretty solid for some of this rain, while Tuesday is a little more
up in the air. The GFS has a pretty solid surge of northwesterly
winds Monday night as the upper trough moves quickly by and dries us
out very rapidly. The Euro is a bit more deliberate with the upper
low, and though perhaps it has a better defined surface low, a post-
frontal northwesterly surge doesn`t look as significant, keeping us
from drying out until Tuesday night. Though I would tend towards a
slower evolution when it comes to these closed/cutoff lows to our
west, I did tamp down PoPs somewhat for Tuesday as the GFS` solution
is at least plausible. There will be time to adjust up (or, perhaps
down) as we gain greater consensus on this evolution.

Despite some deviation here, there is strong consensus in a quick
return to onshore flow for the back half of the week. Thursday looks
to be relatively drier, but there is a slight chance of a shower.
However, potential should increase Friday as lee cyclongenesis over
the Oklahoma Panhandle should result in the development of a new low
and trailing cold front that is on our doorstep by Friday morning.
Look for showers to develop near the front and persist for some time
in the front`s wake. This will set the stage for an unsettled period
leading up to Christmas. And while there`s fairly high confidence in
that, and generally good confidence that colder air will push into
the area, there is significant uncertainty about how that may
translate into wintry precipitation. At this point, there is so much
inconsistency both between models and between individual runs of the
same model, that it`s impossible to state much beyond that it will
be colder, there will be periods of precipitation, and some sort of
wintry precip is possible (but by no means certain!). Indeed, just
to make things more fun, the GFS doesn`t even bring the 850 front
far into our area, if at all, keeping 850 temps well above freezing
for all but our northwest. In the words of my esteemed shift
partner, this is a "warm and gross rain" scenario. Not so sure I`m
convinced about this as reality compared to the Euro, but I put it
there to illustrate that in a place where wintry weather hangs on
razor thin margins, those margins are totally swamped by range of
potential scenarios at this time. Much like in tropical season
with potential threats in the extended period, keep calm, make
sure you have a plan, and stay tuned.

MARINE...

Offshore winds will continue to decrease this afternoon and tonight,
but veer to the east and increase back to near advisory levels
during the day Saturday as surface low pressure lifts up the Texas
coast. Scattered to numerous showers and thunderstorms will be
possible as this low shifts towards the east Saturday night with a
few stronger thunderstorms capable of producing waterspouts Saturday
night through early Sunday morning. A brief period of offshore flow
behind this front will quickly become onshore by Sunday night with
warmer, moist air moving across the cooler shelf waters resulting in
periods of sea fog through Tuesday or Wednesday before a cold front
moves off the coast.

Huffman

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)      40  55  45  67  53 /   0  70  90  10  20
Houston (IAH)              43  58  49  69  58 /   0  40  90  20  30
Galveston (GLS)            52  60  57  66  62 /   0  20  90  40  50

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&

$$

Discussion...11

Friday, December 15, 2017

Dec. 14 17

Northwest Houston, TX, during the early morning.



Thoughts: Felling unwell this week again.

Thursday, December 14, 2017

Dec. 13 17

Frost on my way to work, in northwest Houston, TX, during the early morning.
Northwest Houston, TX, during the early morning.
West Houston, TX, during the early afternoon.
Northwest Houston, TX, during the early evening.

Thoughts: I wasn't able to get write a summary, because I wasn't feeling well in the morning.

Area Forecast Discussion 
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796
FXUS64 KHGX 140211
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
811 PM CST Wed Dec 13 2017

.DISCUSSION...
At 800 PM, surface high pressure was located over the eastern Gulf
and a weak cold front extended from SW MO into central OK and then
into the Texas panhandle. The front will move slowly south
overnight and will cross SE TX late Thursday afternoon. Cirrus
clouds continue to stream over the area and IR imagery shows the
cirrus extending across Mexico and into the Pacific. The
trajectory will keep the cirrus moving over the region tonight. A
light south flow and the cirrus will likely limit the temperature
drop tonight so conditions should be warmer than last night.
Tweaked temps and sky grids to match current obs otherwise the
rest of the forecast looks on track.

Looking ahead, A neutral/slightly negatively tilted short wave
trough will move east late Saturday into Saturday night. A surface
low will approach Matagorda Bay and rain should develop late
Saturday. Showers and thunderstorms look likely on Saturday night
as the low moves across the region. 43

&&

.PREV DISCUSSION... /ISSUED 519 PM CST Wed Dec 13 2017/

AVIATION...
VFR conditions are expected through the period. A front will push
through the area tomorrow reaching CLL around 18Z and IAH around
23-00Z. 11

PREV DISCUSSION... /ISSUED 407 PM CST Wed Dec 13 2017/

DISCUSSION...
Quiet weather for the late week, with a warmer day tomorrow before
a cold front tomorrow night chops temperatures back down. The
forecast gets much trickier for the weekend with rising rain
chances and potential for a coastal low passing through. There may
be some outside potential for locally heavy rain or even some
severe weather, but that potential is very heavily dependent on an
uncertain track for any potential low, and confidence is low. Once
that clears out - likely Sunday - look for quieter weather to
return next week.

NEAR TERM [Through Tonight]...

Satellite (and a look out the window) shows copious coverage of
high clouds both here and across the corner of Southeast Texas
we`re responsible for. This has kept temperatures a little
suppressed, and safely under seasonal averages for high
temperatures.

Tonight, we can probably look for more of the same - on the flip
side of today, this should keep temperatures from falling as far,
and for now keep most of the entire area above 40 degrees, save
for the far northern portion of Houston County where the veil of
high clouds is not quite as thick. Still, even there I stay just
below 40 degrees, so frost should not be a player overnight unless
we get a more significant temp drop.

SHORT TERM [Thursday Through Friday Night]...

A modestly warmer day is expected tomorrow, mainly in the
southwest, but this will be a short-lived trend as a weak cold
front is expected to push through the area as well, before
stalling offshore tomorrow night. Winds will turn northerly and
become a bit gusty overnight, more towards the coast. Rain chances
will be nil for inland areas, with precipitable water showing a
dry column with values near 0.5 inches. A bit of a different story
near the coast, where precipitable water will be more in the
0.75-1.00 inch range Thursday night. By this point the front is
already through, but the front will be nearby, there will be
sufficient moisture present, and we`ll have the help of being in
the right rear quadrant of the upper jet, helping support upwards
motion. All in all, think we`ve got a shot at seeing some showers
in those coastal areas mainly south of I-10. The best chance of
showers will likely be Thursday night, and trail off through
Friday as the front sags a little farther away from the coast,
taking the best rain potential farther offshore.

LONG TERM [Saturday Through Wednesday]...

From there, things start to get tricky. There is pretty solid
model consensus for the development of a coastal low along the
stalled front, which will then move northeastward towards our
area. From there, some fairly small, but very important
divergences in the model begin to emerge. On the bright side (for
us), the Euro brings the surface low ashore near Galveston Bay
late Saturday night. There`s a low level jet of 40-50 knots and
plenty of moisture to help support rain showers. Some CAPE near
the coast would make for some thunderstorm potential. Fortunately,
the upper jet is a little out of phase yet, and things don`t get
quite lined up for heavier rain until everything has moved to our
east late Saturday night. On the other hand, the GFS brings the
low in near Matagorda late Saturday night. The same strong onshore
LLJ exists, but we`re a little better phased with the upper jet.
Again, some CAPE is around near the coast allowing for some
thunder. However, now with surface winds significantly backed
ahead of the low, we`re now looking at a lot of veering winds and
with strong vertical shear, that would make for a low level
hodograph that wouldn`t make some low-topped spinners an outside
possibility. Perhaps more significantly, the strong onshore flow
and dynamics could make for some locally heavy rainfall.

So, that largely presents a best and worst case scenario. For
perspective, the GEFS members range from a third of an inch of
rain to three inches of rain at IAH. For now, have significantly
upped PoPs in this area, but have held off on hitting a severity
until it becomes somewhat more apparent as to what kind of track
we`ll get on this coastal trough/low.

Fortunately, things look to clear out relatively quickly. The
trend will be towards quieter weather for the first half of the
week with a generally dry cold front Tuesday, though there is
another shot for showers very near the coast if there`s enough
moisture return.

MARINE...

Tranquil maritime weather pattern through tomorrow...weak westerlies
over near 1 to 2 foot seas. An early Friday morning cold frontal
passage will increase the likelihood of early day rain turning more
showery into the Friday afternoon hours. Offshore winds will
strengthen to brief advisory during the morning hours...bays and
nearshore water cautions by the afternoon. Advisory level far
offshore winds will come down right around Friday sunset. A fairly
quiet Saturday as northeasterlies veer around the eastern dial and
become onshore by mid day. The approach of a western upper trough
will pull up a more moist southwestern Gulf air mass and produce an
inverted surface trough. Thus...the weather will become increasingly
unsettled going into Sunday as onshore flow strengthens...seas build
with likely rain and storm probabilities. 31

FIRE...
Regional moisture will remain unchanged through early Friday...or
ahead of the next cold frontal passage slated for late Thursday
night into the early Friday morning hours. Afternoon minimum
relative humidities will fall into the lower to middle 40s the next
couple of days. Southwesterly transport will veer northerly Friday
with the passing boundary...strengthen to more moderate levels early
Friday in the wake of the front. Slow deepening of Thursday mixing
depths as it will take surface low 60s to break the stout early
morning inversion. 31

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)      43  66  41  57  38 /   0   0  10   0   0
Houston (IAH)              45  69  44  55  40 /   0   0  20  10  10
Galveston (GLS)            53  67  49  55  48 /   0   0  50  40  10

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&

$$

Discussion...11

Wednesday, December 13, 2017

Dec. 12 17

Northwest Houston, TX, during the early morning.
Northwest Houston, TX, during the early afternoon.


Summary: The day was cool, sunny, and dry. There didn't look to be any precip in any of the locations in the Houston, TX area, during anytime of the day. I didn't see any precip on the radar, over the Houston, TX area, during anytime of the day. I didn't feel, see, or hear any drops of precip, at any of the locations that I was in, during anytime of the day. Wavy thick and thin flat alto stratus clouds looked to be scattered across the sky, during the morning, afternoon, evening, and maybe night. The wind speeds looked to be calm with gentle to  moderate gusts and some occasional really strong 20 mph gusts. It felt cold, during the early morning and early night. It felt very cool, during the mid-morning. It felt a little cool, during the late morning. It felt warm with a very cool wind gusts, during the afternoon. It felt cool with a very cool wind gust, during the early evening. It felt very cool with a cold wind gusts, during the late evening. It felt very cold, during the late night. There were no watches, warnings, alerts, advisories, or weather statements/outlooks issued for the Houston, TX area, that I know of. The low temperatures looked to be in the mid to high 30's and the high temperatures looked to be in the low ot mid 60's with maybe some high 60's, for the Houston, TX area.


Houston, TX Storm Summary: There didn't look to be any precip in any of the locations in the Houston, TX area, during anytime of the day. I didn't see any precip on the radar, over the Houston, TX area, during anytime of the day. I didn't see, or hear about any reports of flooding, or damage caused by the weather, at any of the locations in the Houston, TX area, during anytime of the day.


My Storm Summary: I didn't feel, see, or hear any drops of precip, at any of the locations that I was in, during anytime of the day. I didn't see any precip producing, or thunderstorm type clouds, during anytime of the day. I didn't see any flooding, wet roads, puddles, wet ground, or damage, caused by the weather/ I didn't see any lighting strikes, or hear any rumbles of thunder, during anytime of the day.


Locations: Northwest Houston, TX.


Thoughts: Here comes the cold again...


Area Forecast Discussion 
Issued by NWS Houston/Galveston, TX

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000
FXUS64 KHGX 130526
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
1126 PM CST Tue Dec 12 2017

.AVIATION...
VFR conditions are expected through the period. 11

&&

.PREV DISCUSSION... /ISSUED 836 PM CST Tue Dec 12 2017/

DISCUSSION...
High pressure over west-central Texas will bring clear skies,
light winds and dry air into SE TX tonight. Ideal radiational
cooling should allow for a light freeze over the NE counties
tonight and very cold temperatures elsewhere. Forecast is in good
shape and no significant changes in the short term is needed. 43


PREV DISCUSSION... /ISSUED 347 PM CST Tue Dec 12 2017/

NEAR TERM [Through Tonight]...

With the KHGX radar down along with THOU, it makes it hard to
detect smoke plumes from prescribed burns along the coast. GOES
East still works with GOES 16 en-route so we can still pick up a
couple of hot spots in Brazoria County and Chambers County along
with smoke plumes on visible. The burns are controlled despite
conditions being elevated for fire growth. Humidity levels have
dropped to around 25% across the area with winds around 10 to 15
mph and a few gusts near 20 mph. Tonight temperatures should drop
to the mid 30s for most areas and maybe the low 30s for areas
north of Houston and east of I-45. Freeze warnings have already
been issued for the cold season so that will not be a concern.
Hard freeze warning will be for temperatures at or below 25
degrees and temperatures will not be getting that cold.

SHORT TERM [Wednesday Through Thursday Night]...

Conditions will be fairly quiet tomorrow with maybe elevated fire
weather concerns since relative humidity drop below 30% but winds
will be from the southwest around 10 mph. High temperatures may
reach a couple of degrees higher than forecast right now but
depends upon when cold advection ends and how much boundary layer
mixing occurs. Wednesday into Thursday a clipper system moves
across the Great Lakes and reaches the Mid-Atlantic Thursday. A
cold front with this system should push through the area
relatively unnoticed. This front stalls off the coast and then
Thursday night frontogenetic lift begins to increase along with
divergence aloft due to SW/W flow aloft. An upper low begins to
develop over western portions of Mexico which will support the
enhanced jet stream flow aloft. Rain chances should increase along
the coast and offshore Thursday night into Friday. ECMWF has much
more QPF than the GFS, but the trends are there to increase rain
chances during this time along the coast.

LONG TERM [Friday Through Tuesday]...

Forecast models are trending with a faster, more progressive
pattern compared to yesterday for the weekend time frame. ECMWF
and GFS both develop a closed upper level low over western Mexico
with a stronger short wave trough in the mean NW flow aloft over
the central Rockies. This trough should help move the closed low
but there will likely be some timing issues. For now we have
shifted highest rain chances from Sunday to more late Saturday
into Saturday night. ECMWF now produces quite a bit of QPF and
likely bringing higher moisture into the region. GFS brings
precipitable water values up to 1.5 inches along the coast with a
plume of 1.8 inches towards Lake Charles.

By 00Z Sunday, upper level low over Mexico has moved east into
Texas per ECMWF with the GFS slower. Strong divergence aloft and
quasi-geostrophic forcing will support coastal cyclogenesis with
a surface low forming just off the upper Texas coast Saturday into
Saturday night. This system then pushes into Louisiana with rain
chances pushing as the upper low moves east. Highest rain chances
look to be Saturday night in the 30-40 percent range but could go
higher if models continue to trend with more consistent timing of
the trough. Forecast also leaves some slight rain chances Sunday
given the uncertainty in the forecast and timing differences. Rain
chances could quite possibly clear out sooner, but depending upon
the models, best rain chances could be pushed back. Overall looks
like a decent chance of rain with weather hazard remaining low.
There could be enough elevated instability for a few isolated
storms but otherwise looking for scattered showers to develop.
There certainly will be enough low level and deep layer shear for
storm organization but instability will be lacking for a severe
threat. Nonetheless we do not want to let our guard down since
there will be a strong LLJ which could enhance storms, especially
with regards to rotation but also with rain rates. At this time,
it looks like any heavy rainfall will occur off the coast with the
coast low.

Monday and Tuesday next week high pressure should move over the
area as a cold front moves east with the upper level system.
Temperatures will be close to normal for mid December.

Overpeck

MARINE...

North winds over the bays/coastal waters have already begun to de-
crease this afternoon...and have dropped the SCEC for all but the
offshore waters through this evening. Light offshore flow tonight
should give way to a light W/SW flow tomorrow as the surface high
moves off to the east. However, we should see the return of north
winds by Thurs with the passage of a reinforcing cold front. SCEC
and/or SCA flags will likely be needed by Thurs evening/overnight
into early Fri behind the front. Onshore winds expected to resume
early Sat and then rapidly strengthen as the next system deepens/
develops across the Plains. With a warm/moist flow developing and
overriding the cooler nearshore shelf waters, sea fog could be an
issue for our bays/nearshore waters until the next stronger front
clears the coast late Sunday. 41

FIRE WEATHER...

Elevated fire weather conditions are ongoing this afternoon with
RH values bottoming out between 20-30% along with increasing wind
speeds. Gusts between 15-20 mph will be possible from mid morning
to mid/late afternoon. Similar conditions are expected Wednesday
with winds turning around to the southwest. Winds speeds may not
be as high as today, but humidity levels may drop below 30% again
by afternoon.

Overpeck

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)      35  65  41  63  37 /   0   0  10  10  10
Houston (IAH)              38  63  44  65  41 /   0   0  10  10  10
Galveston (GLS)            45  60  53  67  47 /   0   0  10  10  20

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&

$$

Discussion...43
Aviation/Marine...11

Tuesday, December 12, 2017

Dec. 11 17

Northwest Houston, TX, during the early morning.
Northwest Houston, TX, during the early afternoon.
Northwest Houston, TX, during the early evening.
Northwest Houston, TX, during the late evening.


Summary: The day was cool, sunny, and dry. There didn't look to be any precip in any of the locations in the Houston, TX area, during anytime of the day. I didn't see any precip on the radar, over the Houston, TX area, during anytime of the day. I didn't see, feel, or hear any drops of precip, where I was, during anytime of the day. Alto stratus clouds looked to be scattered to widely scattered across the sky, during the morning, afternoon, evening, and night. The wind speeds looked to be calm with gentle to moderate gusts and maybe some possible moderately strong gusts. It felt very cold, during the early morning. It felt cold, during the mid-morning and late night. It started to feel cool, during the late morning. It felt warm with a cool wind breeze, during the afternoon. It felt cool, during the early evening. It started to feel very cool, during the late evening. It felt very cool, during the early night. There were no watches, warnings, alerts, advisories, or weather statements/outlooks issued for the Houston, TX area, that I know of. The low temperatures looked to be in the high 30's and the high temperatures looked to be in the mid to high 60's with maybe some low 70's, for the Houston, TX area.


Houston, TX Storm Summary: There didn't look to be any precip in any of the locations in the Houston, TX area, during anytime of the day. I didn't see any precip on the radar, over the Houston, TX area, during anytime of the day. I didn't see, or hear about any reports of flooding, or any other event caused by the weather, in the Houston, TX area, during anytime of the day. I didn't see, or hear about any damage caused by the weather, during anytime of the day.


My Storm Summary:  I didn't see, feel, or hear any drops of precip, where I was, during anytime of the day. I didn't see any precip producing, or thunderstorm type clouds, during anytime of the day. I didn't see any flooding, or any other type of event caused by the weather. I didn't see any wet roads, puddles, or wet ground. I didn't see any damage caused by the weather. I didn't see any lightning, or hear any rumbles of thunder.


Locations: Northwest and west Houston, TX.


Thoughts: It was starting to feel warm outside, but now it is starting to feel cold again.