Wind Advisory 11, NWS Houston/Galveston, TX

822 
WWUS74 KHGX 291611
NPWHGX

URGENT - WEATHER MESSAGE
National Weather Service Houston/Galveston TX
Issued by National Weather Service Tallahassee FL
1111 AM CDT Fri Oct 29 2021

TXZ436>439-292300-
/O.CON.KHGX.WI.Y.0011.000000T0000Z-211029T2300Z/
Matagorda Islands-Brazoria Islands-Galveston Island-
Bolivar Peninsula-
Including the cities of Surfside Beach and Galveston
1111 AM CDT Fri Oct 29 2021

...WIND ADVISORY REMAINS IN EFFECT UNTIL 6 PM CDT THIS EVENING...

* WHAT...Northwest winds 25 to 30 mph with gusts up to 35 mph 
  expected.

* WHERE...Matagorda Islands, Brazoria Islands, Galveston Island, 
  and Bolivar Peninsula.

* WHEN...From 9 AM this morning to 6 PM CDT this evening.

* IMPACTS...Gusty winds could blow around unsecured objects. 
  Tree limbs could be blown down and a few power outages may 
  result.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Use extra caution when driving, especially if operating a high
profile vehicle. Secure outdoor objects.

&&

$$

865 
WWUS74 KHGX 291836
NPWHGX

URGENT - WEATHER MESSAGE
National Weather Service Houston/Galveston TX
Issued by National Weather Service Tallahassee FL
136 PM CDT Fri Oct 29 2021

TXZ436>439-292300-
/O.CON.KHGX.WI.Y.0011.000000T0000Z-211029T2300Z/
Matagorda Islands-Brazoria Islands-Galveston Island-
Bolivar Peninsula-
Including the cities of Surfside Beach and Galveston
136 PM CDT Fri Oct 29 2021

...WIND ADVISORY REMAINS IN EFFECT UNTIL 6 PM CDT THIS EVENING...

* WHAT...Northwest winds 25 to 30 mph with gusts up to 35 mph 
  expected.

* WHERE...Matagorda Islands, Brazoria Islands, Galveston Island, 
  and Bolivar Peninsula.

* WHEN...From 9 AM this morning to 6 PM CDT this evening.

* IMPACTS...Gusty winds could blow around unsecured objects. 
  Tree limbs could be blown down and a few power outages may 
  result.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Use extra caution when driving, especially if operating a high
profile vehicle. Secure outdoor objects.

&&

$$

Area Forecast Discussion
National Weather Service Houston/Galveston TX
429 AM CDT Fri Oct 29 2021

.SHORT TERM [Today Through Saturday Night]...

The winds on Thursday blew away more than just my expectations as
some areas experienced gusts up to 50-60 mph. Fortunately, the wind
will not be as gusty today...buuuut it'll still be kinda gusty. The
LLJ on the western side of an area of low pressure to our northeast
is still going strong this morning with 850mb winds of 45-50 knots
over East Texas. Boundary layer decoupling is preventing stronger
gusts from reaching the surface in the overnight hours, but that
will change later in the morning. As the area of low pressure
continues to push off to the east, the pressure gradient will
gradually weaken throughout the day. We'll still have steep low-
level lapse rates at the DALR up to 1.5 km, which is plenty suitable
for mixing winds to the surface. The LLJ will weaken from 45-50
knots in the morning to 30-35 knots by the mid-afternoon hours, so
we'll actually have our highest wind gusts towards the first half of
the day. You'll want to keep your Halloween decorations tied down
for now, even though flying ghosts and floating pumpkins are great
ambiance for spooky season. Winds will be high enough along the
coast today to warrant the issuance of a Wind Advisory for the
barrier islands. As we recall from yesterday, gusty winds equals
efficient mixing so I bumped up MaxT's by a couple of degrees over
NBM guidance (highs in the low 70s but approaching mid 70s out
west).

Surface high pressure edges in overnight on Friday, which will allow
for winds to become relatively light. With clear skies in place,
we'll be set up for sufficient radiational cooling which means
temperatures will plummet into the low to mid 40s across most of
Southeast Texas. We're going to continue walkin' on sunshine right
into Saturday as yet another gorgeous day is on tap for us. Saturday
will feature high temperatures in the mid to upper 70s and overnight
temperatures in the upper 40s/low 50s, but most
importantly...lighter winds thanks to nearby surface high pressure.
Saturday also features the departure of an upper-level trough that
will leave behind subtle ridging as a parting gift. Unfortunately,
this marks the beginning of yet another warming trend.

Batiste

&&

.LONG TERM [Sunday through Friday]...

Surface high pressure over the Central Plains and low pressure
over West Texas will allow for a light onshor wind to return to SE
TX. The air mass will remain dry and generally sunny skies are
expected. MaxT values will be near or just slightly warmer than
seasonal levels with values reaching 80 degrees or so. Clear skies
are expected Sunday night with an increase in cluds expected
Monday as the surface high moves east and onshore winds continue
to pull deeper moisture back into SE TX. PW values reach an inch
by Tuesday but moisture profiles still look too dry for
precipitation. Monday and Tuesday should again warm into the lower
80's with partial sunshine and light onshore winds.

Things begin to change Wednesday and Thursday as the zonal flow
becomes more amplified as a strong short wave drops into the
desert SW and moves east. The best lift associated with the short
wave arrives Wednesday night into Thursday. Fcst soundings take on
a senmi-saturated moisture profile by 06z Thursday. Some
inconsistenecies between the faster GFS and the slower ECMWF. The
Canadian favors the GFS as does most of the ensemble guidance but
will carry lowish PoPs into the Saturday in case the ECMWF is on
to something. Trended cooler with temps on Fri/Sat but
temperatures will be dependent on whether the front crosses the
coast Thursday or Friday. 43

&&

.MARINE...

The pressure gradient will remain tight today but will begin to
relax this afternoon as a deep surface over the Ohio valley shifts
east. A Small Craft Advisory is in effect for the Bays and Gulf
waters through 00z. Seas will remain between 5 and 8 feet today
and Bay waters will remain choppy to rough today. Weak high
pressure will be located over SE TX on Saturday and move east of
the region Saturday night. This will allow a light onshore flow to
develop by Sunday morning. A light to moderate onshore flow will
then persist into early next week. With the lighter wind regime,
seas will flatten and remain generally near or below 3 feet
through Tuesday.

The strong offshore wind has produce low water levels and the Low
Water Advisory will remain in effect until 00z. Water levels
remain 1.5 to 3.0 feet lower than normal. Water levels will remain
below normal through Saturday and return to near normal levels by
Sunday. 43

&&

.FIRE WEATHER...

Minimum RH values this afternoon will once again drop into the 20%-
30% range. This in combination with northwesterly winds around 20
mph and wind gusts up to 30 mph this afternoon, fire weather
conditions will remain elevated today. Winds finally become lighter
on Friday night as surface high pressure approaches, but afternoon
RH values will remain on the low side (25%-35%) throughout the
weekend. Please continue to exercise extreme caution if working
outside with any flammable materials.

Batiste

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)      72  43  75  48  80 /   0   0   0   0   0
Houston (IAH)              72  46  75  51  80 /   0   0   0   0   0
Galveston (GLS)            73  55  75  64  78 /   0   0   0   0   0

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...Wind Advisory from 9 AM this morning to 6 PM CDT this evening
     for the following zones: Bolivar Peninsula...Brazoria
     Islands...Galveston Island...Matagorda Islands.

GM...Low Water Advisory until 7 PM CDT this evening for the following
     zones: Galveston Bay...Matagorda Bay.

     Small Craft Advisory until 7 PM CDT this evening 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...Galveston Bay...Matagorda Bay...
     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.

&&

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