Skip to main content.

National Weather Service Forecast Discussion

Related quick links> 5 Day Forecast, Local Advisories, Drought Monitor, UV Forecast, Air Quality Forecast 
649
FXUS64 KHGX 030149 AAA
AFDHGX

Area Forecast Discussion...UPDATED
National Weather Service Houston/Galveston TX
849 PM CDT Thu Jul 2 2026

...New AVIATION...

.KEY MESSAGES...

- Closely monitoring weather for the the Independence Day with
  increased heat stress expected.

- Hot Weather continues with peak heat index values reaching 100-
  110F (38-43C).

- Daily rain chances. Light streamer showers possible in the
  morning, then scatters/isolated storms during the afternoon.

&&

.DISCUSSION...
Issued at 315 PM CDT Thu Jul 2 2026

The broader synoptic pattern has not changed significantly across SE
Texas. A robust ridge is still situated across the Tennessee-Ohio
Valley/Mid Atlantic region today, with midlevel heights upwards of
596-597 dam (around the the-the climate percentile). On Friday,
this ridge will shift eastward and weaken, with heights decreasing
and slowly meshing into the broader tropical high to the south on
Saturday, which amplifies to around 591-592 dam this weekend.
Though, southeast Texas is still expected to remain on the
peripheral of both these ridges, with midlevel heights remaining
around 590-593 dam (~70-the climate percentile) and 850mb
temperatures around 18-21C (~70-the climate percentile). With
this persistent onshore flow and WAA we`ll continue to see hot
weather across SE Texas for the foreseeable future. Rain chances
will vary from day to day, though, with some weak impulses passing
aloft, no strong capping and onshore theta e advection, there can
certainly be some occasional showers and thunderstorms. This is
most likely to manifest as spotty streamer showers over the Gulf
early in the morning, then as some scattered/isolated showers and
thunderstorms in afternoon near the coast along the sea breeze. As
noted yesterday, low level lapse rates are also very steep,
nearly dry adiabatic at 8-9 DegC/km, so any pop up storms could
produce some modest downbursts at least, though not particularly
strong.

In general, hot weather continues with highs in the 90s and triple
digit heat indices ranging from 100-110F (38-43C). WBGT values
indicate that heat stress on the human body will be high, possibly
reaching extreme in spots during the afternoon. There will be daily
chances of rain, possibly as light streamer showers over the
Gulf/Coast in the morning and maybe some pop-up showers/storms in
the afternoon, especially along the sea breeze.

Independence Day is this Saturday, and as many of you have likely
heard, it will be the Semiquincentennial (the anniversary) of the
founding of the United States of America. Outdoor events and
celebrations for this milestone will likely draw in massive
crowds, thus extra care was put into the July 24th forecast,
specifically with regards to heat stress.

Heat index values these last few days have generally remained under
108, mainly as a result of modest afternoon mixing lowering
humidity. The NBM generally struggles with this mixing, so I`ve
adjusted dewpoints down slightly in the afternoon, generally keeping
to the higher-end observed values from our ASOS stations (as to not
mix out too much). Model guidance has been pinging temps to be
generally higher on Saturday. Yesterday NBM was a tad too cool in
spots, so I`ve increase highs slightly to compensate, closer to
around the the percentile in the NBM. The pressure gradient does
weaken on Saturday, and thus winds become very calm in the morning
through the early afternoon. Timing/intensity of the sea breeze
can be tricky to pin down on day 3 (since it falls beyond the
cams), thus to error on the side of caution, I mixed in some NBM
13th percentile to simulate a slower & weaker afternoon sea
breeze. Cloud cover is another parameter that can be difficult to
narrow down beyond the 48 hour high-res window, though this
current synoptic pattern has tended to produce few-scattered
q-fields in the afternoon. Model vorticity and UV are both
especially weak on Saturday, in addition to NBM guidance trending
lower on PoPs for the 24th as well. With this in mind, I`ve opted
to lower cloud cover slightly (in addition to capping PoPs around
10%).

The culmination of all these changes still produces highs in the 90s
and heat indices around 101-109F for the the Independence Day.
The resulting Wet Bulb Globe Temperature values are forecasted
around 86- 91 between 12PM-6PM. Resulting heat stress on the human
body is forecasted to be high (level 3/4), reaching extreme
(level 4/4) in a few isolated spots. Extra emphasis on the
*isolated spots* portion, as the spatial & temporal scale of those
extreme values is small (mostly within the Houston metro between
2-4PM). In layman`s terms, it`ll feel a warmer than the typical
summer days as of recent, though not dramatically different.

Despite more conservative heat projections, the current forecast
doesn`t suggest a need for heat headlines at this moment, though
that could change with the next forecast cycle. Regardless of
whether or not a heat advisory is issued, it would still be wise to
practice heat safety. If you plan to spend the day outdoors, make
sure you wear light cloths, apply sunscreen and stay hydrated by
drinking plenty of water. Heat is the #1 weather-related killer in
the U.S. each year, and often people greatly underestimate it`s
danger. Even if the heat isn`t advisory-strength, more people
outside means that more cases of heat illnesses will likely emerge
as a result.

03

&&

.AVIATION...
(00Z TAF Issuance)
Issued at 848 PM CDT Thu Jul 2 2026

Afternoon storms are on the decaying phase of their with most
activity wrapping up across all terminals by 01Z. Thereafter, we
return to VFR conditions. Light winds return overnight. Latest
guidance brings MVFR CIGs back for inland locations, especially
KDWH/KCXO. Further for terminals further to the south, FEW/SCT
MVFR CIGs may be accompanied by brief patches of fog, but any
reduction in VIS will be short lived through 14Z. S`ly winds then
return along with the threat of additional seabreeze storms.
Latest hi-res guidance keeps most of the activity closer to the
coastal zones. Given the low confidence in the extent of these
storms further inland, I have elected to keep the mention of
TSRA/SHRA N of Texas Hwy 35, but we will have to monitor the
overnight model runs to see if the next TAF package will need to
append any rain/TS wording. In the afternoon, SE-SSE winds pick up
to 7-12 kts.

&&

.MARINE...
Issued at 315 PM CDT Thu Jul 2 2026

Light S/SE winds around 10 knots and calm seas of 1 to 3 feet are
expected throughout the next several days. Light streamer showers
could develop over the Gulf waters each morning. Isolated to
scattered thunderstorms could develop along the sea breeze in the
afternoon near the coastline and bays.

03

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)  76  95  77  96 /  10   0   0   0
Houston (IAH)  77  95  78  96 /  20  10  10  10
Galveston (GLS)  83  90  82  90 /  20  20  10  10

&&

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

$$

DISCUSSION...03
AVIATION...Enriquez
MARINE...03

NWS HGX Office Area Forecast Discussion