September 2021: Hurricane Nicholas

[weatherguy425]

It really wouldn't take too much to get a closed circulation out of the setup this weekend, into next week. Either way - looks like an increasing chance of heavy rain for portions of Texas. 12 GFS illustrates the *potential* pretty well.

[Scott747]

Moves inland n of Tampico with a fairly well defined circulation, first time in a few days for the model. Moves nnw and into central texas. Not a prolific rainmaker but would be some decent amounts across areas to the e.

[weatherguy425]

Moves inland n of Tampico with a fairly well defined circulation, first time in a few days for the model. Moves nnw and into central texas. Not a prolific rainmaker but would be some decent amounts across areas to the e.

The risk of heavy rain could become a bigger threat post-landfall if steering does breakdown. Just something to watch, of course.

[don]

12z GFS is coming in a little more aggressive. 999 offshore of Tampico.

It looks similar to the ICON with a tropical storm riding the coast and lifting north into the state just inland as a weakness develops to the north.

[Stratton20]

Hope we get some decent rainfall totals in the next 7 days, we just dont need flooding rains

[Scott747]

Our potential system is finally in range of my friend the HAFS-B (experimental hurricane model) with it showing some slight organization a little further offshore of n mex/lower texas coast and moving nnw.

[Stormlover2020]

Can u send pic

[Cpv17]

The vorticity on the Euro is much further off the coast than what the GFS shows.

[Stratton20]

12z Euro takes the vorticity into the central texas coast

[sambucol]

How strong of a storm does it show?

[Cpv17]

How strong of a storm does it show?

Weak. Just a wave.

[TxLady]

WALKER County now under a "Burn Ban" . First one in a while...and, hopefully, won't last too long!

[Stratton20]

do yall think their is some flood potential next week? I mean a ton of gulf moisture getting pulled northward definitely could create some problems

[Scott747]

18z ICON gets a little further n (Brownsville) before land interaction. Still more or less a sloppy mess but any less land interaction will give any potential system more time to organize. And while the ICON isn't considered one of the more reliable models it can still be somewhat decent.

[tireman4]

000
FXUS64 KHGX 072015
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
315 PM CDT Tue Sep 7 2021

.DISCUSSION...

High pressure and dry conditions will be the story of the next
several days across Southeast Texas. This should drive afternoon
temperatures to higher than average levels, but we will get a bit
of a break from less oppressive humidity, and nighttime
temperatures near or below average. Rain chances will be minimal
at most until the late half of the weekend, when the return of
deeper Gulf moisture will boost humidity and rain chances.


.SHORT TERM [Through Wednesday Night]...

High pressure dominating our weather. Dry air mixing down in the
wake of the front. Northern CWA dewpoints in the mid to upper 50s
has kept it warm but dry. Surface high over the Corsicana area and
will weaken slightly as it slips southeastward tonight/Wednesday
morning. Winds Wednesday will be varying from northwest in the
morning turning to the northeast/east as it warms up in the
afternoon. Seabreeze should again intrude to the southern counties
of the CWA late in the afternoon/early evening. Skies will be partly
cloudy to sunny and with temperatures recovering from the mid 60s to
upper 60s well inland and around 70 south around sunrise into the
lower 90s coast to the upper 90s well inland. Next cold front will
be pushing south and should move into the CWA late Wednesday
night/early Thursday morning. Moisture profiles look sparse and
ongoing subsidence should maintain the cap so rain chances are very
low. An isolated shower will be possible after 3 am Thursday mainly
over the south.


.LONG TERM [Thursday Through Tuesday]...

Come Thursday morning, we`ll be looking for a lingering weakness
in subtropical ridging over the Gulf, but the upper high
dominating the Four Corners region will be increasingly extending
its influence over our area. This should pretty effectively keep
things hot and dry over Southeast Texas into the weekend. Thursday
looks to be the driest day of this long term section with
dewpoints in the middle 50s north of the Houston metro. However,
even Friday and Saturday should see pretty dry conditions as
onshore flow will struggle to re-establish itself until later on
Saturday.

The drier air will promote a greater diurnal range of
temperatures - so, while afternoon highs should reach into the
upper half of the 90s inland, we should also see low temperatures
in the 60s up north as well. Of course, the hot temps and low
humidity will also make for some uncharacteristically dry feeling
days, with min RH values around and north of I-10 looking to fall
below 30 percent.

While the upper ridge axis should gradually come closer to our
area over the weekend, it will also be weakening as it does so.
This should set us up for a change to a more typically summer-like
pattern on the south side of that upper ridge, and newly
persistent onshore flow beginning to pump deeper Gulf moisture
over the area. I`ve got rain chances starting to creep back across
the Gulf waters late on Saturday, with better chances for rain
over land emerging on Sunday. Also, we`ll see that diurnal
temperatures range tighten up as higher humidity keeps overnight
lows warmer and tamps down afternoon highs. Of course, as far as
apparent temperatures go, that slight dip in temps will be easily
offset by that increase in humidity, so relief is probably not an
appropriate word to use here.

Uncertainty in the specifics of what next week will look like are
driven by the fact that this surge of moisture will be driven by
an approaching wave that could...theoretically...have some
potential for development into a tropical cyclone. This seems like
a pretty low probability outcome - outside of a few stray GFS
runs, the guidance does not seem too enthused about this wave`s
prospects, as there are questions about how supportive the western
Gulf environment may actually be for a tropical cyclone.

But while the specifics are a bit fuzzy, there`s considerably more
confidence that whatever...it...will be next week, there will be a
solid slug of moisture coming with it. Guidance takes precipitable
water as low as half an inch at the dry extreme, and consensus
appears to be below an inch on Saturday. By Sunday afternoon, it`s
progged to be back up in the 1.75 to 2 inch range. Fortunately,
while the ensemble guidance definitely suggests a high PW anomaly
in the area early next week, it`s also not currently expected to
be climatologically extreme. For now, this appears to be a window
to get some more widespread rain showers, and given recent trends
in the area, that could well be a good thing. Still, we all know
how quickly things can escalate in this area at this time of year,
so we`ll also watch with a wary eye to be on top of any changes
in the most likely scenario.


&&

.AVIATION [18Z TAF Issuance]...

VFR. Some patchy fog possible again for CXO/UTS/CLL/SGR/LBX mainly
09-13z and should be patchy/variable IFR. Winds today NE becoming
E/SE late then NW toward morning. Cirrus should continue to
meander about overhead through Wednesday.

&&

.MARINE...

Light winds and low seas will persist for the next several days as
high pressure dominates the region. With winds pretty light and a
greater than usual range of temperatures over land, the
land/seabreeze pattern should be more pronounced. A more
pronounced onshore flow will become established later this weekend
along with gradually building seas. Chances of showers and
thunderstorms will be minimal while high pressure is in command,
and will increase over the coastal waters as early as Saturday
night, depending on how quickly deep moisture increases over the
area.

&&

.PRELIMINARY POINT TEMPS/POPS...

College Station (CLL) 69 98 72 97 70 / 0 0 0 0 0
Houston (IAH) 71 97 73 97 71 / 0 0 10 0 0
Galveston (GLS) 80 92 80 92 80 / 0 10 10 0 0

&&

.HGX WATCHES/WARNINGS/ADVISORIES...

TX...None.
GM...None.

&&

$$

DISCUSSION...Luchs
SHORT TERM...45
LONG TERM...Luchs
AVIATION...45
MARINE...Luchs

[DoctorMu]

Dewpoint of 57°F in College Station. Loving it, even if the temp is in the mid to upper 90s.

So far in the 18Z GFS run and even weaker tropical system easing into south Texas. May mean less rain - we'll know in 30 minutes.

[Stratton20]

Safe to say even the GFS doesnt even know whats going to happen next week, so much flip flopping! 12z run had a “stronger system” and now this run nothing at all

[weatherguy425]

Safe to say even the GFS doesnt even know whats going to happen next week, so much flip flopping! 12z run had a “stronger system” and now this run nothing at all

There hasn’t been much flip flopping. We’re talking the difference of 5-10 MB of pressure. The 12Z solution wasn’t really a “stronger“ system. The 18Z, again, implies a chance for this to close off and become a tropical system as it (probably) approaches the lower Texas or Northeast Mexico coast. Differences, in the grand scheme of things, are small run to run.

[Scott747]

Yeah I'm not sure what that poster is talking about. The vorticity is plenty strong on this run. It's actually a little 'wetter' even though it's more coastal or just offshore. Could end up with one of these situations of a 25-50 mile difference having implications on any potential flooding issues.

Still probably a toss up with what the NHC will do. I could see a 10/20% area highlighted in the BoC sometime late tomorrow or Thursday,

[Cpv17]

Safe to say even the GFS doesnt even know whats going to happen next week, so much flip flopping! 12z run had a “stronger system” and now this run nothing at all

Well on the 12z there was less land interaction. That’s why it had a stronger vorticity signal. We’re talking 30-40 miles here. Could make a huge difference like Scott said.