887
FXUS64 KHGX 161919
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
219 PM CDT Wed Jul 16 2025

...New DISCUSSION, MARINE, TROPICAL...

.KEY MESSAGES...
Issued at 1147 AM CDT Wed Jul 16 2025

- Low rain chances will persist through Thursday morning.

- Increasing tropical moisture will lead to increased coverage of
  showers and thunderstorms late Thursday through Friday with
  locally heavy rainfall possible.

- NHC continues to monitor a disturbance that will be entering the
  northern Gulf later today or tonight, giving it a 40% chance of
  development into a tropical system within the next 48 hours.
  Regardless of development, increased rain chances are likely
  late Thursday through early Saturday.

&&

.DISCUSSION...
Issued at 1147 AM CDT Wed Jul 16 2025

Drier air has definitely filtered across Southeast TX and the GOES
Total Precipitation Water imagery is currently showing PWs of 1.5"
to 1.6" across much of the area and will help limit rain chances
for today through Thursday morning. There is still some wiggle
room for a quick shower to develop this afternoon, but coverage
overall will be fairly isolated. The high temperatures are
expected to be mostly in the lower 90s, but some locations could
see highs reaching the mid 90s. The heat indices will stay in the
lower 100s for much of the region.

We will see moisture starting to recover sometime mid morning or
early afternoon on Thursday as a warm moist airmass associated to
the tropical disturbance currently located over the Florida
Peninsula, begins to filter in from the east southeast. I did
notice that although the NBM shows us fairly dry during the
morning to early afternoon hours, a few vort maxes ejected
westward from the disturbance could move over us during the late
morning to late afternoon hours and may trigger some isolated
showers/storms during that period. We will have to see if moisture
and instability will be enough for rain development, however.

By the evening to early night hours, the disturbance is progged to
move westward, roughly over the LA coastal locations, and will
continue to lead to a rise in low and mid level moisture over
Southeast TX. We may start to see showers and thunderstorms
developing/moving over the areas south of I-10 and east of I-45 by
this time. We will see the shower and thunderstorm activity
expand further west and northwest during the overnight to morning
hours and is expected to further increase as we progress into
Friday afternoon. This is when models show local PWs reaching the
2.0" to 2.5" range for much of the area, which could lead to
period of moderate to heavy rainfall, in particular for areas near
and east of I-45 and near and south of I-10. Ponding of water
along roadways and poor drainage areas is possible. The rains
could also affect your commute, thus, make sure to check the radar
and local traffic before departing. PWs will decrease from late
Friday into Saturday morning, and many areas could see PWs of
1.8" to 2.0" by Saturday afternoon. Therefore, we may have lower
chances of rain on Saturday. The forecast currently is carrying
PoPs of around 15-35% PoPs for Saturday.

More details regarding the disturbance can be found in the
Tropical Discussion below.

Low rain chances are expected starting on Sunday as drier air
moves into Southeast TX and persists through the mid week
timeframe. High temperatures may increase also into the mid to
upper 90s during the second half of the week.

Cotto

&&

.AVIATION...
(12Z TAF Issuance)
Issued at 554 AM CDT Wed Jul 16 2025

Areas of MVFR cigs/vis in our northern zones should trend to VFR
by mid-morning. Mostly dry conditions are expected today. A
prevailing southerly wind is expected to develop this morning,
becoming more southeasterly during the afternoon. Winds generally
around 10 knots though occasional gusts over 15 knots cannot be
ruled. Winds should decrease by the evening.

Self

&&

.MARINE...
Issued at 1147 AM CDT Wed Jul 16 2025

Light to occasionally moderate onshore winds and seas of 2 to 3
feet will continue for the next several days. Lower rain chances
will persist through Thursday morning as drier air prevails over
the region.

From late Thursday into Friday, rain chances are expected
to increase as a tropical disturbance moves westward from the
north-central Gulf waters and into the LA coastal region. There
still remains uncertainty regarding the development and track of
this disturbance. The 2PM EDT Tropical Weather Outlook continued a
40% chance of formation through the next 48 hours. More
information regarding the track and intensity will be known once
the system moves into the Gulf waters and an Air Force Hurricane
Hunter aircraft investigates it. For this forecast package, I have
continued to bring in slightly higher seas of around 4 feet for
the offshore waters, but these heights can change within the next
upcoming forecasts.

Please continue to monitor the upcoming forecasts.

Cotto

&&

.TROPICAL...
Issued at 1147 AM CDT Wed Jul 16 2025

Not too many changes made to the previous tropical discussion.
Satellite continues to depict an area of low pressure currently
moving westward over the Florida Panhandle and is expected to
move into the northeastern or north-central Gulf waters later
today or tonight. Environmental conditions may be favorable for
further development as the system continues to move over the
waters and a tropical depression could form as it approaches the
coast of LA on Thursday or Friday. There`s still uncertainty
regarding the strength and track of this system, given that its
unknown how far into the waters the system will be. More
information will be known once the system moves into the Gulf
waters and an Air Force Hurricane Hunter can investigate it.

Regardless of formation, the system could bring periods of
moderate to heavy rainfall over portions of Southeast TX from late
Thursday into early Saturday. Please continue to monitor the
progress of this system as well as the latest forecasts.

Cotto

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)  92  72  94  74 /   0   0  10   0
Houston (IAH)  93  75  93  77 /   0   0  10  30
Galveston (GLS)  91  80  91  79 /   0   0  10  50

&&

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

$$

DISCUSSION...Cotto
AVIATION...Self/Adams (18Z issuance)
MARINE...Cotto
TROPICAL...Cotto