Beach Hazards Statement 9, NWS Houston/Galveston, TX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
1141 PM CDT Tue Oct 27 2020

.AVIATION [06Z TAF Issuance]...

LIFR To IFR CIGs will continue across area through the morning
will ceilings down to 300 to 800ft. Scattered showers and patchy
fog is also leading to lower visibilities at times. These
conditions won't improve until the cold front pushes through the
area tomorrow afternoon bringing a rather quick return to VFR
conditions by 21z-00z. Though expect breezy to gusty northerly
winds tomorrow afternoon behind the front to continue into the
evening. VFR conditions then prevail through Thursday.

Fowler

&&

.PREV DISCUSSION /Issued 628 PM CDT Tue Oct 27 2020/...

.DISCUSSION...

Southeast Texas remains split by a stalled front, with
temperatures only reaching the mid 40s in Burleson County, while
the Galveston Bay area is seeing temperatures reach the middle to
upper 70s. A reinforcing push to shove the front off the coast is
coming tomorrow, but until then, look for continued dreary
conditions for most of the area.

The upper low that will help get the front moving again will also
increase chances that our clouds/fog/mist/drizzle/muck/gross/you
get the picture will manage to become rain showers, so look for
PoPs to be considerably higher tomorrow.

Finally, once a drier airmass settles in behind a fully cleared
front, we should see fairer weather make its way into Southeast
Texas. While we'll finish this week still fairly cool, expect
things to gradually warm into next week.

.SHORT TERM [Through Wednesday Night]...

Bit of an interesting quirk to the weather today...one that
ultimately caused me to mess up my aviation forecast in the
Houston area. The stalled front around Houston grew relatively
diffuse, and the low clouds and fog in the post-frontal
environment grew to cover right down to the coast. While I
forecasted some improvement in conditions this afternoon, the
atmosphere had a twist for me - convection associated with, but on
the extreme edge of TS Zeta's influence essentially collided with
the front and shoved some of that pre-frontal airmass back across
the Houston metro!

Now, this happened late enough, winds are still northerly due to
Zeta's circulation, and it remained mostly cloudy (just at a much
higher altitude), that sensible weather in the area isn't much
different from the forecast for anyone not flying a plane. But it
did require a big TAF amendment, and was at least fairly
interesting (if annoying) to watch occur.

Now, an interesting quirk doesn't necessarily mean long lasting,
so I'm expecting things to wash out fairly quickly tonight as an
upper low makes its way from El Paso to West Texas/the Panhandle
on its way northeast, while Zeta accelerates northward across the
Gulf. We should find ourselves back in muck pretty quickly, with
plenty of low clouds and fog for all. Later in the night into
tomorrow morning, as these two weathermakers make their closest
approach to SE Texas, we should see enough lift that we'll
transition from foggy/misty/drizzly more to rain showers. It's
already happening over the Gulf where there's some decent
convection, so here's hoping that's a strong sign this process is
already set in motion.

Finally, as stronger offshore flow rolls in as the upper low rolls
on by to our northwest, we should see a deeper push of continental
air - and likely a dry slot - shove on in late Wednesday afternoon
into Wednesday evening, boosting cloud bases, scouring out
moisture, and getting us started on a long stretch of fairer
weather. But more on that in the long term section.

.LONG TERM [Thursday Through Tuesday]...

With the main upper trof/closed low having exited the state (to the
E/NE), the main forecast issue for Thurs looks to be elevated winds
(especially across the southern half of the CWFA including the Gulf
waters). Conditions should improve by Fri as the upper ridge begins
to build from the west...and surface high pressure settles over the
state. Below average temperatures on Thur/Fri are expected to begin
warming over the weekend as light onshore winds return to the area.
Another cold front is forecast to move through SE TX Sun...but with
very low/nil POPs given the very limited return moisture. This cool
dry weather should continue on into the start of next week.

.MARINE...

Would normally have a SCEC out on the Gulf for winds today and
tonight, but since they only appear in the CWF text product, and
that headline gets trumped by the Small Craft Advisory in place
for tomorrow's Zeta/cold front combo, have opted to leave it off.
I imagine that it's probably already pretty obvious to mariners
that conditions on the Gulf today are probably not too great out
there.

While I haven't gone as high as some guidance suggests, have
definitely trended towards the stronger end of the model envelope
for winds behind the cold front Wednesday and Wednesday night.
For Thursday and beyond, look for northwesterly winds to gradually
veer northerly, then northeasterly through the weekend while
staying generally moderate. The pressure gradient may tighten up
enough for some periods of gustier winds early next week.

&&

.PRELIMINARY POINT TEMPS/POPS...

College Station (CLL)  45  56  43  64  44 /  60  60   0   0   0
Houston (IAH)          60  66  49  66  49 /  60  60   0   0   0
Galveston (GLS)        70  72  55  69  55 /  50  60   0   0   0

&&

.HGX WATCHES/WARNINGS/ADVISORIES...

TX...None.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION from 7 AM CDT Wednesday
     through Thursday morning for the following zones: Galveston
     Bay...Matagorda Bay.

     Small Craft Advisory from 7 AM Wednesday to 7 AM CDT Thursday
     for the following zones: Coastal waters from Freeport to
     Matagorda Ship Channel TX out 20 NM...Coastal waters from
     High Island to Freeport TX out 20 NM...Waters from Freeport
     to Matagorda Ship Channel TX from 20 to 60 NM...Waters from
     High Island to Freeport TX from 20 to 60 NM.

&&

DISCUSSION...Luchs
SHORT TERM...Luchs
LONG TERM...41
AVIATION...Fowler
MARINE...Luchs