Thayer, Texas Weather Forecast Discussion

576
FXUS64 KBRO 200347
AFDBRO
Area Forecast Discussion
National Weather Service Brownsville TX
1047 PM CDT Fri Sep 19 2025
...New DISCUSSION, MARINE...
.DISCUSSION...
Issued at 1045 PM CDT Fri Sep 19 2025
An unsettled weather pattern continues this weekend into next week
as upper level divergence persists and a series of mid-level
disturbances pass over Deep South Texas along the eastern periphery
of a mid-level high pressure centered over northwestern Mexico. The
same pattern over the past several days continues with convection
developing along the seabreeze boundary by mid-day across the
coastal areas, gradually pushing westward throughout the afternoon
and early evening hours before dissipating throughout the evening
and overnight hours, though overnight convection over the Gulf could
spill inland at times. PWAT values of around 1.6-2.0 inches are
likely to persist across the region through this weekend, highest
along the coast. As such, a low to medium (20-50%) chance of showers
and thunderstorms are likely today and tomorrow, mainly across the
eastern half of the northern ranchlands as well as the lower and mid
RGV, with the greatest chances east of I-69 E. Lightning, gusty
winds and heavy rain are possible, especially closer to the coast
where PWAT`s are highest. Additional minor flooding is possible
within the heaviest rain brought by slow-moving thunderstorms, which
have resulted in flood advisories for portions of the lower RGV the
past 2 days. Meanwhile, a less than 20% is anticipated across the
upper RGV and Rio Grande Plains, where PWAT`s are the driest/lowest.
Monday and Tuesday, PoP`s lower slightly, though still remain a low
to medium (20-40%) chance along and east of US-281/I-69C as the mid-
level high shifts eastward into western Texas. However,
probabilities rebound to a medium (40-60%) chance across all of Deep
South Texas on Wednesday as a cold front pushes into, and stalls,
across southern-central Texas before lifting northward and away from
the CWA into the weekend, thus lowering PoP`s to a low (20-30%)
chance. Lightning, gusty winds and brief heavy rain remain
possible.
Near-average high temperatures gradually rise to slightly above
average throughout the remainder of this weekend and into the middle
of next week, with mid/upper 90`s across inland Deep South Texas and
lower 100`s across portions of the upper RGV and Rio Grande Plains
by Monday and Tuesday. As clouds build and chances of rain
increase across the region towards the later part of the week,
temperatures gradually cool by a few degrees, though still
remaining above average further inland. Mostly minor (level 1 of
4) heat risks, with pockets of moderate (level 2 of 4), continue
through tomorrow before becoming a mainly moderate heat risk,
with pockets of major (level 3 of 4), Monday through Wednesday and
minor to moderate Thursday through Saturday.
&&
.AVIATION...
(00Z TAFS)
Issued at 616 PM CDT Fri Sep 19 2025
For the most part, convective activity has diminished this
evening, though there continues to be showers popping up southwest
of KHRL, which may continue over the next hour or so, bringing
brief periods of moderate to heavy rain, before clearing up. VFR
conditions continue overnight and through tomorrow aside from the
possibility of morning showers at KBRO and again in the afternoon
across all terminals as showers and thunderstorms develop,
bringing additional rounds of lightning, gusty winds and heavy
rain, possibly reducing visibility and lowering ceilings as noted
within the PROB30`s. Gentle easterly winds of around 5-10 knots
continue, though becoming light and variable overnight tonight.
&&
.MARINE...
Issued at 1045 PM CDT Fri Sep 19 2025
Slight to moderate (2-3 ft) seas prevail into next week as a result
of gentle easterly to southeasterly winds, becoming gentle to
moderate southeasterly to southerly winds on Monday. Chances of
showers and thunderstorms continue.
&&
.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE             76  91  77  92 /  30  60  30  50
HARLINGEN               73  93  73  94 /  10  50  10  50
MCALLEN                 76  95  77  96 /  10  40  10  30
RIO GRANDE CITY         73  96  74  97 /  10  30   0  10
SOUTH PADRE ISLAND      81  87  81  88 /  40  50  50  60
BAYVIEW/PORT ISABEL     76  89  77  91 /  20  50  30  50
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...None.
&&
$$
SHORT TERM...65-Irish
LONG TERM....65-Irish
AVIATION...65-Irish

NWS BRO Office Area Forecast Discussion