Brownsville, Texas 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

529
FXUS64 KBRO 152324
AFDBRO

Area Forecast Discussion
National Weather Service Brownsville TX
624 PM CDT Sun Mar 15 2026

...New AVIATION...

.KEY MESSAGES...
Updated at 622 PM CDT Sun Mar 15 2026

Key Messages:

 - Temperatures soar to 10-20 degrees above average this
   afternoon, with record breaking to near-record breaking
   temperatures possible.

 - Strong cold front arrives late this evening, bringing strong
   northerly winds and crashing relative humidity values. A Red
   Flag Warning and Wind Advisory go into effect late this evening
   through tomorrow afternoon for most of the region.

 - Strong northerly winds behind the front also result in life-
   threatening rip currents, dangerous surf, minor coastal
   flooding and hazardous marine conditions late tonight and into
   the early parts of this week.

 - A Gale Warning is in effect for the Lower Texas coastal waters
   late this evening through tomorrow afternoon as gale force
   northerly winds and very rough seas are expected.

 - Elevated fire weather concerns persist each afternoon through
   next weekend.

&&

.DISCUSSION...
Issued at 151 PM CDT Sun Mar 15 2026

The main focus of the forecast for Deep South Texas and the Rio
Grande Valley continues to be the wind, fire, coastal and marine
hazards resulting from a strong cold front moving through tonight.
This front extends from a rapidly intensifying low pressure system
currently over the Midwest, ahead of a deepening trough over the
Central Plains. Lowering pressure heights over the Southern Plains
and the Sierra Madre interacting with a surface high pressure
over the Gulf have already led to gusty winds, occasionally
gusting to 45 mph, and higher, over the Lower RGV, this morning
and early afternoon. As the low departs further east into the
remainder of this afternoon, northwesterly to westerly lower level
winds on the low`s backside will continue to progress a dry line
into the region, bringing lower relative humidity. Meanwhile, the
pressure gradient is anticipated to loosen due to rising heights,
gradually reducing winds across the CWA into this evening as the
dry line progresses eastward to possibly as far east as inland
Kenedy County and the western portions of the Lower RGV. Due to
the narrow window of breezy conditions coinciding with lower
relative humidity, have held off on issuing a Fire Danger Statement
(RFD) for this afternoon. However, it is highly urged to refrain
from outdoor burning as the region remains within a D2 to D4
(Severe to Exceptional) Drought with abundant cured fuels; stronger
gusts could quickly spread wildfires. Moisture pooling east of the
dry line and enhancing lift ahead of the front may produce isolated
showers and thunderstorms late tonight across the Lower RGV to the
coast, where there is a (15-30%) of rain, with the best chance along
the coast.

Another byproduct of the dry line is the compressional heating of
the lower atmosphere, likely leading to near-record to record-
breaking heat this afternoon as temperatures soar 10-20 degrees
above average, reaching as high as the upper 90s to lower 100s
across most inland areas.

Now onto the biggest focus: the fire and coastal hazards associated
with the fierce northerly winds and significantly drier air ushered
southward into the CWA by the strong cold front expected to enter
the Northern Ranchlands and the Rio Grande Plains potentially
between 9-11 PM tonight and pass through the entire region by the
pre-dawn hours tomorrow morning; strong northerly winds of 20-30
mph, with gusts to at least 45 mph are expected region-wide. Have
increased wind and wind gust speeds west of US-281 and added a
Wind Advisory for Jim Hogg, Starr and Zapata counties from 10 PM
tonight until 8 AM tomorrow morning, where the majority of CAM
models have consistently agreed with the latest HREF probabilistic
guidance, which suggests a medium to high chance of gusts up to
55 mph, or higher, for several hours following the front. Another
Wind Advisory is in effect for all counties further east from 10
PM tonight until 1 PM tomorrow evening as gusts up to 45 mph, or
higher, could persist into the early afternoon hours, especially
along and near the immediate coast. As much drier air is advected
southward via the strong northerly winds, the combination of very
low relative humidity and breezy to windy conditions will lead to
critical fire weather conditions and a Red Flag Warning remains
in effect across all of Deep South Texas, with the exception of
the barrier islands, from 10 PM tonight to 7 PM tomorrow evening.
See the FIRE WEATHER section below for more details. Meanwhile, at
the coast, the strong winds will result in dangerous surf and
life threatening rip currents. A High Surf Advisory and a Rip
Current Statement are in effect from 7 AM to 7 PM tomorrow.
Hazardous surf, dangerous rip currents and minor coastal flooding
are likely to continue into the beginning of this week.

Otherwise, winds continue to diminish throughout tomorrow night.
Cold air advection behind the front results in below average
temperatures through Tuesday with highs only reaching into the 60s
on Monday, which is nearly a 30-35 degree drop from this afternoon`s
highs. Overnight lows fall to the 40s/50s tomorrow night, with low
40s likely across the Northern Ranchlands. Average temperatures are
expected Wednesday as winds become southeasterly and then above
average by Thursday. Breezy and dry conditions continue through
next weekend, keeping fire weather concerns elevated.

&&

.AVIATION...
(00Z TAFS)
Issued at 622 PM CDT Sun Mar 15 2026

Through 00z Tuesday....The main weather concern to aviation ops for
the terminals through the forecast period will be the strong to
potentially damaging northerly winds developing later tonight into
Monday, which will likely have major impacts/implications particularly
to east to west oriented runways.

VFR conditions, by and large, will prevail through the 00z TAF cycle.
There could be a few MVFR-LIFR clouds at times, particularly tonight.

Ahead of an approaching cold front, winds will continue out of the
south with speeds between 7-15 kts, occasionally gusting as high
as 20 kts through the evening hours before fading. In response to
the cold fropa later this tonight, winds will shift out of the
north and become strong with speeds between 15-25 kts. Winds will
gusts generally between 35-45 kts, however, there could be
isolated gusts as high as 50 kts or so on Monday.

&&

.MARINE...
Issued at 151 PM CDT Sun Mar 15 2026

A tightened pressure gradient continues to result in strong
southerly winds and moderate (3-5 feet) seas this afternoon,
gradually decreasing to fresh to strong throughout the later
afternoon and early evening hours as the gradient loosens. A Small
Craft Advisory remains in effect until 10 PM this evening. In the
hours leading up to the arrival of the strong cold front late
this evening, there is a low to medium (20-50%) chance of rain as
isolated to scattered showers and thunderstorms develop. Following,
the front passes through, quickly resulting in gale force northerly
winds and very rough seas, continuing through tomorrow morning,
with gale force gusts persisting through tomorrow afternoon. A
Gale Warning goes into effect across all Lower Texas coastal
waters from 10 PM tonight until 7 PM tomorrow evening. Small
Craft Advisory and/or Small Craft Exercise Caution headlines are
likely tomorrow night into Tuesday as winds and seas gradually
improve. Gentle to moderate southeasterly to southerly winds and
moderate seas return by Wednesday morning, continuing with dry
conditions into the remainder of this week.

&&

.FIRE WEATHER...
Issued at 151 PM CDT Sun Mar 15 2026

A Red Flag Warning remains in effect for all of Deep South Texas,
with the exception of the barrier islands, from 10 PM tonight until
7 PM tomorrow evening. Strong northerly winds and rapidly crashing
relative humidity values along and behind a strong cold front
arriving late this evening will lead to elevated to critical fire
weather conditions through tomorrow afternoon. Northerly 20 foot
winds of 20 to 30 mph, gusting as high as 35 to 45 mph or higher,
and minimum relative humidity values as low as 10-35 percent are
likely, with the lowest relative humidity along/west of US-281. As
cured fuels remain abundant within the ongoing D2 to D4 (Severe
to Exceptional) Drought across the region, it is strongly
recommended to refrain from outdoor burning.

&&

.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE             59  64  53  72 /  20   0  10  10
HARLINGEN               52  66  47  72 /  10   0   0   0
MCALLEN                 55  68  49  76 /  10   0   0   0
RIO GRANDE CITY         52  68  47  75 /   0   0   0   0
SOUTH PADRE ISLAND      59  62  58  67 /  20  10  10  10
BAYVIEW/PORT ISABEL     56  63  53  70 /  20   0   0  10

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...Red Flag Warning from 10 PM this evening to 7 PM CDT Monday for
     TXZ248>255-351-353>355.

     Wind Advisory from 10 PM this evening to 8 AM CDT Monday for
     TXZ248-249-252.

     Wind Advisory from 10 PM this evening to 1 PM CDT Monday for
     TXZ250-251-253>255-351-353>355-451-454-455.

     High Rip Current Risk from Monday morning through Monday evening
     for TXZ451-454-455.

     High Surf Advisory from 7 AM to 7 PM CDT Monday for TXZ451-454-
     455.

GM...Small Craft Advisory until 10 PM CDT this evening for GMZ130-132-
     135-150-155-170-175.

     Gale Warning from 10 PM this evening to 7 PM CDT Monday for
     GMZ130-132-135-150-155-170-175.

&&

$$

SHORT TERM...65-Irish
LONG TERM....65-Irish
AVIATION...23-Evbuoma