Skip to main content.

National Weather Service Forecast Discussion

Related quick links> 5 Day Forecast, Local Advisories, Drought Monitor, UV Forecast, Air Quality Forecast 
220
FXUS64 KHGX 131129
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
629 AM CDT Mon Jul 13 2026

...New AVIATION...

.KEY MESSAGES...

- A stalled boundary and deep tropical moisture will lead to
  scattered to widespread showers and thunderstorms on Monday.
  Locally heavy rainfall with a Slight Risk (level 2 of 4) of
  Excessive Rainfall across most of SE Texas.

- Additional showers and thunderstorms will be possible on
  Tuesday. Greatest chances of locally heavy rainfall will be in
  the Brazos Valley, but isolated downpours will be possible
  across all of SE Texas. A slight risk (level 2 of 4) of
  excessive rainfall is in place for most of SE Texas on Tuesday
  as well.

- A gradual drying/warming trend should take shape heading into
  the second half of the work week.

&&

.DISCUSSION...
Issued at 1133 PM CDT Sun Jul 12 2026

Deep tropical moisture continues to funnel into SE Texas as we
kick off the work week. Satellite derived PWATs continue to show
values around 2.1-2.2". The high moisture will work in concert
with daytime heating and a slow moving boundary that is expected
to stall as it moves south into SE Texas and will result in
another day of scattered to widespread showers and thunderstorms.
Greatest coverage of activity is expected during late morning
through early evening hours. A lull in activity is anticipated for
Monday night with another round of activity set for Tuesday.

High PWAT values and soundings point to an increasing potential
for storms to produce heavy downpours that could result in minor
urban ponding and minor flooding in areas with poor drainage.
Forecast rainfall totals continue to fall into the 1-3" range.
Given the saturated profile being observed with soundings and
light steering winds, storms with heavier downpours could result
in localized totals of up to 5" (especially if storms train over
the same areas).

WPC has highlighted portions of Southeast Texas in their excessive
rainfall outlook over the next few days.

- Monday, 6/13: A Slight Risk (level 2 of 4) for most of SE Texas,
  with the Matagorda Bay region in a Marginal Risk (level 1 of
  4).
- Tuesday, 6/14: A Slight Risk (level 2 of 4) for most of SE
  Texas, with southern portions of SE Texas in a Marginal Risk
  (level 1 of 4).

The latter part of the week will feature isolated activity to
start, with a drying trend increasing towards the weekend.

The increase in cloud cover combine with increased rain chances
will continue to keep temperatures on the cooler side during the
afternoon. Highs will be in the upper 80s to low 90s through
midweek. Expect heat and humidity to both increase going into the
weekend as highs climb into the mid 90s by Friday and into the
upper 90s this coming weekend. Heat indices are also expected to
increase into the triple digits by the weekend.

Bailey

&&

.AVIATION...
(12Z TAF Issuance)
Issued at 625 AM CDT Mon Jul 13 2026

Some patchy MVFR cigs continue this morning near CLL to CXO, but
these should quickly lift back to VFR in the next couple hours.
SHRA and TSRA will develop near the coast in a few hours, pushing
northward through the Houston metro terminals. Meanwhile,
SHRA/TSRA will also be developing near the northern terminals
(CLL, UTS, CXO), pushing southward. These clusters will likely
collide somewhere near IAH/DWH and nearby sites. This will
continue through the afternoon, slowly waning into the evening
hours. Cigs will drop to MVFR/IFR north of the Houston metro,
though IAH and DWH will be right on the edge of MVFR/VFR. The
southern terminals will likely remain VFR. SHRA and possibly TSRA
will redevelop late in the period into Tuesday morning near the
coast, migrating inland again through the morning hours.

&&

.MARINE...
Issued at 1133 PM CDT Sun Jul 12 2026

South to southeasterly winds around 10-15 knots and 2-4 ft seas
will prevail through most of this week. A pattern of late night
into early morning showers and thunderstorms is anticipated
through at least midweek, some of which could produce heavy
downpours and a reduction in visibilities. The majority of the
activity is expected to move inland by the mid- morning hours each
day, but isolated afternoon activity will still be possible over
the coastal waters. Lower rainfall chances are expected to return
by Thursday, but very isolated overnight activity will still be
possible.

Bailey

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)  88  73  84  72 /  70  70  70  30
Houston (IAH)  88  75  84  75 /  80  60  80  10
Galveston (GLS)  88  80  88  83 /  70  50  80  10

&&

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

$$

DISCUSSION...Bailey
AVIATION...Young
MARINE...Bailey

NWS HGX Office Area Forecast Discussion