Area Forecast Discussion
Issued by NWS Houston/Galveston, TX

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975
FXUS64 KHGX 131124
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
624 AM CDT Sun Jul 13 2025

...New AVIATION...

.KEY MESSAGES...
Issued at 1218 AM CDT Sun Jul 13 2025

- Chances for scattered showers and storms continues Sunday into
  early next week. A few strong storms could produce locally heavy
  rainfall and gusty winds.

- Moderate to High rip current risk along Gulf-facing beaches on
  Sunday.

- Potential for high temperatures to peak in the mid 90s after the
  middle of next week. Heat indices in the triple digits for most
  of the week.

- A coastal trough approaches the north-central Gulf coast towards
  the end of the work week bringing an increasing chance of
  showers/storms.

&&

.DISCUSSION...
Issued at 1218 AM CDT Sun Jul 13 2025

Taking a look at the radar estimated rainfall totals from Saturday,
it`s very apparent the vast majority of the area did not see
rain...but those that did saw quite a bit. The big winner for
Saturday was eastern Montgomery County where an estimated 2-3+" fell
today, and in fact most of the rain that fell on Saturday occurred
north of I-10. The reason I`m bringing that up is because Sunday
looks to favor a similar rainfall pattern. Latest HREF reflects most
of the rainfall occuring north of I-10 again on Sunday. This is due
to greater moisture availability across the Brazos Valley/Piney
Woods (PW values greater than 2.0") and closer proximity to a
shortwave trough extending from central Texas to northeast Texas.
Coverage of showers/storms is expected to increase in the late
morning to afternoon hours as convection moves in from central
Texas. A combination of outflow boundaries and daytime heating is
expected to lead to additional convection ahead of the incoming
broken line of storms. As we saw on Saturday, any of the stronger
storms will have the potential to produce locally heavy rainfall and
strong wind gusts. Rainfall rates could exceed 2-3"/hr, so an
extended period of heavy rain over one area could result in pockets
of 1-3" of rainfall totals. As a result, WPC has portions of the
Brazos Valley/Piney Woods in a marginal risk (level 1 out of 4) of
excessive rainfall for Sunday. As far as temperatures go, expect
high temperatures in the low 90s with a few spots of mid 90s and low
temperatures in the mid to upper 70s.

The shortwave trough remains in place going into Monday although
there is some slight uncertainty on when or if it evolves into a
cutoff low around the Red River. In some deterministic guidance this
occurs a bit earlier which would take away most of the PVA by
Monday. As you can imagine that would have an impact on rain
chances. For now, we`re playing it safe and keeping rain chances
somewhat elevated on Monday, but after that rain chances go on a
decreasing trend into midweek. This lines up with a gradually
expanding mid level high that will be centered over the southeastern
CONUS. That explains the slight warming trend up into the mid 90s (a
few spots in the upper 90s can`t be completely ruled out) around
midweek. Heat indices will be in the triple digits for most of the
week, but dew points should mix out enough to keep heat indices just
below advisory criteria. Towards the end of the work week, a coastal
trough develops in the eastern Gulf and tracks westward into the
north-central Gulf coast. This will lead to increasing chances of
showers/storms...check out the Tropical section down below. Now I
already know what y`all are thinking ("check out the WHAT!!!"),
but the NHC has given this coastal trough a low probability of
tropical development over the next 7 days. More details below.

Batiste

&&

.AVIATION...
(12Z TAF Issuance)
Issued at 619 AM CDT Sun Jul 13 2025

The primary feature of interest is a complex of tsra to the
northwest of our area. This activity is expected to push southeast
and bring scattered shra/tsra to portions of our area. There
remains uncertainty regarding tsra coverage. That being said, we
lean towards our northern terminals having the best just chance of
tsra (thus the TEMPO groups). Areas farther south continue to have
PROB30s due to the uncertainty. Whether or not we get tsra near
the coast is particularly uncertain. Most models show no tsra at
the coast later today. But moisture levels are high and could
allow for tsra development farther south. Any sub-VFR conditions
this morning should improve to VFR in the next few hours. However,
sub-VFR conditions will possible in any thunderstorm that occurs.

&&

.MARINE...
Issued at 1218 AM CDT Sun Jul 13 2025

Light to occasionally moderate onshore flow will persist through
next week. Southeasterly winds overnight look to briefly approach
the threshold for caution flags with sustained winds around 15 kt.
This elevated onshore flow will keep seas around 4 ft through Sunday
along with increasing the rip current risk, so be sure to take the
proper precautions if visiting any Gulf-facing beaches. Daily
chances for scattered showers and storms continue into early next
week with some storms having the potential to produce locally heavy
rainfall, gusty winds, and elevated seas. There will be a brief
period of drier conditions around midweek before shower/storm
chances return at the end of the work week as a coastal trough
transitions from the eastern Gulf to the north-central Gulf coast.

Batiste

Beach conditions: There is a Moderate to High risk of rip current
along all Gulf-facing beaches on Sunday. Use extra caution! Always
follow beach flag systems, swim near a lifeguard and away from piers
and jetties.

JM

&&

.TROPICAL...
Issued at 1218 AM CDT Sun Jul 13 2025

You might be surprised to see a Tropical section in the AFD, but
rest assured there is no need to worry. This is only being
addressed since there will probably be questions about the low
(20%) probability of tropical development in the central/eastern
Gulf over the next seven days. Going into early next week, a
trough of low pressure is expected to develop near or around the
Big Bend region of Florida (far eastern Gulf) and drift westward
towards the central Gulf staying right along the coast. Some
gradual development of this coastal trough is possible around or
after midweek. The vast majority of ensemble members take this
trough of low pressure into the north-central Gulf coast bringing
that region rounds of heavy rainfall. Towards the end of the work
week, some of that moisture drifts into the Upper Texas coast
bringing an increase in rain chances for our area. Other than
increased rain chances late in the work week, no other impacts are
expected for Southeast Texas at this time.

Stay up to date on the latest Tropical Weather Outlooks from the
National Hurricane Center at hurricanes.gov and stay up to date on
the latest forecasts for Southeast Texas at weather.gov/houston

Batiste

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)  90  74  91  74 /  50  20  30   0
Houston (IAH)  92  76  92  76 /  50  10  50   0
Galveston (GLS)  91  82  90  82 /  30  10  40  10

&&

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

$$

DISCUSSION...Batiste
AVIATION...Self
MARINE...Batiste