Gale Warning 3, NWS Houston/Galveston, TX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
1133 PM CST Thu Jan 13 2022

.AVIATION [06Z TAF Issuance]...

Light and variable winds have settled in over the area with clear
skies. Like last night, patchy fog will be possible at LBX and SGR
with visibility down to 3 to 6 miles at times. Any fog will
dissipate by the mid morning giving way to VFR conditions that
continue through the evening. Southerly winds will pick up during
the day with speeds around 8 to 12kts with occansional slightly
higher gusts. A cold front will move through the area late tonight
passing through CLL just after midnight, then down through IAH by
sunrise bringing a northerly wind shift. Not much precipitation
is expected with the FROPA, but MVFR cigs of 2000-3000ft will be
possible.

&&

.PREV DISCUSSION /Issued 512 PM CST Thu Jan 13 2022/...

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

Clear skies should continue into tonight, allowing for some decent
diurnal cooling with low temperatures falling into the 40s. Winds
will become light and variable as a surface high moves over SE Texas
early in the evening. The combination of these light winds and clear
skies could help develop some radiation fog. Though, drier dewpoints
in 30s/40s will help keep fog development mostly patchy.

Early Friday morning, southerly winds will develop in the wake of
the passing surface high. Warm air advection from the SW will
strengthen, increasing highs into the mid 70s. Onshore flow at the
surface will increase moisture throughout the day, bringing
dewpoints up in the 40s/50s by Friday evening. Fog development will
be more favorable Friday night, with lows cooling into the 40s/50s.
Any fog that does develop Friday night will be blown away with the
passage of a cold front early Saturday morning. Models seem to be in
fairly good agreement with the timing, bringing the front to the
Brazos valley around 2 AM and later offshore by around 9 AM, as the
associated surface low passes into Louisiana. Though, since the
models have been accelerating the FROPA, it may move offshore much
quicker. Scattered showers will develop along the front, though most
rainfall will be focused along the coast and coastal plains, with
PWATS near 1.0. Strong, gusty, northerly winds will develop in the
wake of the front, along with increased cloud cover.

03

.LONG TERM [Saturday Through Thursday]...

Opa! FROPA! With the strong surface cold front pushing off the coast
by the mid-morning hours...out goes the rain, in comes the winds,
and down goes the temperatures. First up, the rain. Moisture
convergence along the frontal boundary increases PW values up to
1.1"-1.2" south of I-10 and 1.3"-1.4" offshore. Resultingly, this is
where we have the highest PoPs given the greater moisture
availability. With virtually no instability in place, you can expect
only rain showers to accompany FROPA. Rain chances drop quickly
following the front as dry air surges in. Next up, the winds. Strong
northwesterly winds will follow in the wake of the cold front with
sustained winds of 20-25 mph for most locations. Along the coast
(mainly the barrier islands), winds will range from 25-30 mph, so a
Wind Advisory is likely for Saturday afternoon/night. Lastly, the
temperatures. Now this was a tricky one...the timing of FROPA means
everything to Saturday's high temperature forecast. Majority of
model guidance supports an early FROPA, so most of Southeast Texas
won't break out of the 50s (which is a good 20 degree difference
from Friday's highs). A light freeze is expected across most of
Southeast Texas on Saturday night with temperatures dipping down
into the low 30s. The exceptions will be along the coast and in the
metro area where lows in the mid to upper 30s are anticipated.

If you have any outdoor plans for Sunday, expect cold and dry
conditions along with a northwesterly breeze. When we factor in the
winds...it'll feel quite a bit colder than the air temperature. Wind
chill values will range from the low to mid 20s across Southeast
Texas on Sunday morning, so plan your outdoor attire accordingly!
Temperatures on Sunday afternoon will only top out in the low 50s,
so a jacket would be comfortable to wear throughout the day. On
Sunday night, our far northern locations will drop below freezing
once again with low temperatures in the low 30s, but the remainder
of Southeast Texas will bottom out in the mid to upper 30s. Surface
high pressure slides east of the area by Monday night leading to a
gradual warming trend into early next week. By Monday, we're in the
60s and by Tuesday we'll be back in the 70s.

Our next cold front looks to arrive some time on Wednesday. For it
being this far out, there is surprisingly good agreement on FROPA
timing between the GFS and Euro (afternoon hours). In this scenario,
southwesterly flow ahead of the front would lead to sufficient
prefrontal heating, so temperatures will likely reach the upper 70s
for those near and south of I-10. Rain showers are expected with
this front as well, with a somewhat similar moisture availability
scenario to Saturday's front. However, the upper-level trough
associated with Wednesday's front is pretty weak, so moisture will
linger over the area and not expecting as much as a cool down (but
it'll still get fairly chilly during the overnight hours). The flow
aloft remains zonal, which allows for numerous embedded shortwaves
to move overhead. This means more rain is on the horizon! The
highest PoPs for now are along and south of I-10 where greater
amounts of moisture will be available. The bulk of the rainfall next
week looks to be on Thursday and Friday, so take advantage of the
end of this work week being nice and dry!

Batiste

.MARINE...

Light westerly winds will continue to persist through Friday
afternoon before winds become southwesterly ahead of an approaching
cold front. Wind speeds increase on Friday night ahead of the front
as well, so a Small Craft Advisory will precede the frontal passage.
The cold front will push offshore by late Saturday morning/early
afternoon with rain showers along its boundary. Behind the front is
where most of the impacts become apparent. Strong northwesterly
winds in the wake of the front with sustained winds around 30-35
knots with gusts up to 40-45 knots. As a result, a Gale Watch has
been issued for the Gulf Waters from Saturday mid-morning through
Sunday mid-morning as a result. Expecting seas to increase to 8-12
feet with occasionally higher seas by Saturday night. Additionally,
with the strong offshore flow, we'll have to keep an eye on the
potential for low water during low tides. There will be a gradual
decreasing trend for both winds and seas on Sunday. Expect the
offshore flow to prevail through Sunday night before onshore flow
returns by late Monday as surface high pressure slides east of the
area.

Batiste

&&

.PRELIMINARY POINT TEMPS/POPS...

College Station (CLL)  43  74  46  52  31 /   0   0  10   0   0
Houston (IAH)          46  74  52  55  34 /   0   0  20  10   0
Galveston (GLS)        54  72  57  60  39 /   0   0  20  30   0

&&

.HGX WATCHES/WARNINGS/ADVISORIES...

TX...None.
GM...Gale Watch from late Friday night through Sunday morning 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.

     Small Craft Advisory from 9 PM Friday to 3 AM CST Saturday for
     the following zones: 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.

&&

SHORT TERM...03
LONG TERM...Batiste
AVIATION...Fowler
MARINE...Batiste