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753
FXUS64 KHGX 302338
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
638 PM CDT Thu Apr 30 2026

...New AVIATION...

.KEY MESSAGES...

- Shower and storm chances further increase late tonight and
  Friday as the next storm system moves in. A Flood Watch is in
  effect for localized heavy rainfall. A few strong to severe
  cells cannot be ruled out. Hazardous marine conditions are
  anticipated.

- Rain ends Friday night followed by cooler and breezy conditions
  for the remainder of the weekend.

- A gradual warm-up during the first half of the week.

&&

.DISCUSSION...
Issued at 210 PM CDT Thu Apr 30 2026

Stalled frontal boundary near the coast this afternoon and some
elevated convection ongoing across northern parts of the area.
This will likely continue into the evening. With less cloudiness
south of I-10, I wouldn`t be surprised to see some late
afternoon/evening development right near the front too.

Western upper trough will be advancing toward the area tonight and
Friday. With increasing large scale lift, broadening upper
diffluence, a series of impulses traversing overhead, deep Gulf
moisture in place, a likely developing frontal wave, and
sufficient instability/shear...we should see several "waves" of
showers and storms track across the region between late tonight
and late Friday evening.

All said, we`re still looking for a swath of 2-4" rains across
parts of the region with some localized 6" amounts possible.
Exactly where this swath sets up is dependent on where the
surface front and frontal wave develops to our west. There was
more uncertainty in previous model runs, but for the most part,
12z guidance is mostly coming on board favoring locations along
and north of the I69/I10 corridor for seeing the higher
accumulations. A Flood Watch has been issued for a good part of
the area...which may or may not need to be adjusted as trends are
observed.

**One note about this watch: since the precip will come in
 multiple waves...I think that the ground should be able to handle
 most of this rain. As time progresses and the ground becomes more
 saturated, the primary concern is for locations where this
 focusing axis sets up...they`ll be prone for
 regenerating/training storms capable of producing significant
 rain rates that could produce several inches of rain in a short
 time period. Street flooding will occur in these cases along with
 some rises on rivers/bayous (see the hydro section below).**

Elevated stronger cells north of the surface front could be a
hail risk. Along and south of the surface front (southern/coastal
areas) could see an isolated tornado/waterspout and wind risk as
well.

This storm system will push east and southeast of the region
during the late evening and overnight hours Friday. Colder, drier
air will then filter into the region just in time for the
weekend.

A gradual modifying/warming trend ensues early next week followed
by our next chances of rain toward midweek.  47

&&

.AVIATION...
(00Z TAF Issuance)
Issued at 632 PM CDT Thu Apr 30 2026

Expect poor flying conditions for the next 24 hours with periods
of SHRA/isolated TSRA, MVFR/IFR ceilings, reduced visibilities,
and gusty winds. The cold front has moved through the Houston
terminals this afternoon and was currently over KLBX. Expect the
front to reach KGLS this evening. Ceilings will lower to IFR/MVFR
levels at remaining terminals this evening in the wake of the
front. Scattered SHRA will impact KCLL/KUTS/KCXO this evening. The
main precip event will begin after 09Z and last until Friday
evening. Mesoscale models show two time windows with enhanced
convection: 10-15Z Friday and again 19Z Friday-02Z Saturday. Have
TEMPO or PROB30s these periods for TSRA, lower visibilities, and
wind gusts 25-35 kts. SHRA should gradually diminish after 02Z
Saturday. Winds will back to the north and increase late
Friday/Friday evening with gusts 20-25 kts likely inland and 30-35
kts for the coastal terminals.

35


&&

.MARINE...
Issued at 210 PM CDT Thu Apr 30 2026

Light southeast winds this afternoon will gradually back to a
more easterly direction and increase in speed tonight. Caution or
advisory flags may be required by late night near the Galveston
Bay area with some 15-25 knot speeds or gusts. Winds will further
increase on Friday as a storm system moves into the area bringing
intermittent strong storms. By late afternoon and early evening a
front will be pushing off the coast and north and northeast winds
will increase to 25 to 35 knots with some higher gusts and seas
will build to 7 to 12 feet Friday night and Saturday. A Gale
Warning will likely be required. Rain will taper off Friday night,
but winds and seas will remain elevated into Saturday. Conditions
should gradually improve Sunday. Light southeast flow returns by
Monday.  47

&&

.HYDROLOGY...
Issued at 210 PM CDT Thu Apr 30 2026

Anticipating multiple waves of heavy rain beginning as early as the
pre-dawn hours on early Friday morning. Rainfall rates will likely
exceed 2-3" per hour. There is potential for extended periods of
heavy rainfall due to training storms, which can cause instances of
flooding especially in urban areas, low-lying areas, and areas with
poor drainage. The highest rainfall totals are still anticipated to
occur along and north of I-10. Currently looking at widespread
amounts of 2-4" with isolated higher totals of 6+" possible. This
rainfall will cause rises on area rivers and watersheds. Action to
minor stage flooding is the most likely outcome, but cannot entirely
rule out isolated instances of moderate stage flooding depending on
where the most rainfall accumulates. As a result, a Flood Watch has
been issued for most of Southeast Texas from 3 AM Friday through 4
AM Saturday

The majority of the area (outside of Harris County) remains in a
moderate to severe drought, so most of this will be beneficial
rainfall. However, the potential is definitely there for too much
rainfall occuring in a short period of time, which can quickly lead
to street flooding. Remember that you can monitor updated river
forecasts via the NWS NWPS webpage (https://water.noaa.gov/) and as
always do not drive through any flooded roadways. Turn Around, Don`t
Drown.

Batiste/KLG

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)  60  61  51  72 /  80  90  60   0
Houston (IAH)  64  67  54  75 /  60  90  80   0
Galveston (GLS)  70  75  59  75 /  40  80  80   0

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...Flood Watch from 3 AM CDT Friday through late Friday night for
     TXZ164-176>179-195>200-210>213-226-227-300-313.

GM...Gale Watch from Friday evening through Saturday afternoon for
     GMZ330-350-370-375.

     Gale Watch from Friday afternoon through Saturday afternoon for
     GMZ335-355.

&&

$$

DISCUSSION...Self
AVIATION...35
MARINE...Self

NWS HGX Office Area Forecast Discussion