997
FXUS64 KBRO 231801 AAC
AFDBRO

Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
1201 PM CST Sun Feb 23 2025

...New AVIATION...

.UPDATE...
Issued at 942 AM CST Sun Feb 23 2025

Slowed down the decrease in cloud cover and rise in temperatures
for the remainder of the day. Morning sounding indicated a nearly
15F surface inversion with a thick overcast to 750mb. Early
visible satellite loops show stratus cover all of Deep South
Texas. Clearing line beginning to show up along the Rio Grande but
breaks in the overcast should be slow for the afternoon keeping
temperatures at least 2-5 degree below previous forecast.

&&

.SHORT TERM...
(Today through Monday)
Issued at 207 AM CST Sun Feb 23 2025

Now through Monday...

A 500mb trough swings through Texas into Monday, kicking the coastal
low further east across the Gulf and bringing much drier air into
Deep South Texas. PWAT values are expected to drop from near the
75th percentile at sunrise to below the 10th percentile by sunset.
Sunshine should re-emerge from west to east through the day,
bringing temperatures back into the 60s and low 70s. Surface winds
are expected to diminish and flip easterly by this evening. Light
winds and clearing skies tonight will promote efficient radiational
cooling, allowing temperatures to free fall after dark back into the
low to mid 40s. Fog is expected to form late tonight, especially
across the ranchlands where temperatures may crash the furthest.

Monday will be even better, with wall to wall sunshine, comfortable
humidity, light winds eventually turning southerly, and temperatures
warming back towards normal, topping off in the mid 70s to low 80s.
A cooler day in the 60s is expected on the island with life-
threatening rip currents still expected in the chilly surf.

&&

.LONG TERM...
(Monday night through Saturday)
Issued at 207 AM CST Sun Feb 23 2025

The long term forecast period will feature a progressive and mainly
zonal 500 mb flow aloft pattern. This will result in continued
fluctuations in temperatures as a cold front is set to push
through the forecast area Wednesday evening into Thursday. Despite
the progressive nature of the pattern, dry conditions are
expected to prevail.

We start off the long term Monday night where a chilly night awaits
as low temperatures are expected to dip into the upper 40s across
the Northern Ranchlands to the low-mid 50s along the RGV, and upper
50s along the island. Aided by the return of southeast winds, high
temperatures on both Tuesday and Wednesday are expected to climb
into the upper 70s along and east of IH-69E to the low-mid 80s west
of IH-69E. Temperatures will be cooler along the beaches given the
offshore flow influences.

Wednesday night into Thursday, a moisture-starved cold front is
expected to sweep across the region reducing temperatures and
humidity levels. This cold front will be driven by mid-upper ridging
developing over the western U.S. and downstream troughing over the
eastern U.S. Daytime high temperatures on both Thursday and Friday
are expected to hold in the 70s areawide. Will have to monitor
20ft winds and the potential for a fire weather statement Thursday
and/or Friday, mainly along and west of IH-69C given antecedent
dry conditions, relative humidity levels dropping to less than
25%, and the elevated fuels in that region.

Temperatures look to rebound once again on Saturday and Sunday with
a return of the 80s across much of the region courtesy of a return
flow out of the south-southeast and ridging/higher heights
developing. Overnight low temperatures Tuesday night through
Sunday night will mainly be in the 50s/60s, with the exception of
Thursday night where lows are progged to be in the 40s and 50s
amid the cold fropa. Despite the fluctuation in temperatures
through the extended, anomalies are expected to average out to
slightly warmer than normal levels.

&&

.AVIATION...
(18Z TAFS)
Issued at 1135 AM CST Sun Feb 23 2025

MVFR overcast skies slowly rise and begin a west to east clearing
trend this afternoon. Clear VFR conditions are expected for all
areas after 00Z with winds becoming light and variable to calm.
Conditions become favorable for fog formation between 10Z-15Z with
a 40-50% chance of IFR to LIFR visibility due to fog. Any fog
formation should burn off quickly by 16Z with VFR and light winds
the remainder of the day Monday.


&&

.MARINE...
Issued at 942 AM CST Sun Feb 23 2025

Pressure gradient is showing signs of relaxing across the lower
Texas coast with a low pressure area and front boundary over the
Louisiana Gulf waters continuing to track steadily eastward. Small
Craft Advisories have been cancelled with wind and seas
diminishing well below advisory levels. Much improved marine
conditions are expected by Monday morning with winds turning
southerly and seas becoming slight. Fair marine conditions are
expected for the remainder of the week with high pressure
prevailing. A weak frontal boundary brings brief northerly winds
Thursday.

&&

.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE             62  44  73  53 /  20   0   0   0
HARLINGEN               64  42  76  51 /  10   0   0   0
MCALLEN                 67  46  79  54 /  10   0   0   0
RIO GRANDE CITY         68  42  80  49 /   0   0   0   0
SOUTH PADRE ISLAND      57  51  66  59 /  20   0   0   0
BAYVIEW/PORT ISABEL     58  45  69  53 /  20   0   0   0

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...High Rip Current Risk through late tonight for TXZ451-454-455.

GM...None.
&&

$$
UPDATE...59-GB
SHORT TERM...56-Hallman
LONG TERM....23-Evbuoma
AVIATION...59-GB