037
FXUS64 KBRO 232003
AFDBRO

Area Forecast Discussion
National Weather Service Brownsville TX
303 PM CDT Thu May 23 2024

...New SHORT TERM, LONG TERM, MARINE...

.SHORT TERM...
(Tonight through Friday night)
Issued at 303 PM CDT Thu May 23 2024

Heat will continue to be the primary concern during the short term
period.  An upper level ridge over Northern Mexico and South Texas
will support broad subsidence across the region, limiting cloud
cover during the afternoon. South easterly surface winds will
continue to advect warm, humid air into Deep South Texas, which will
support the development of low clouds overnight, as well as increase
temperatures and dewpoints. The combination of these factors will
lead to higher apparent temperatures overnight and during the day
Friday. Apparent temperatures are expected to remain in the upper
80s to low 90s tonight, and exceed 115 for much of the area Friday
afternoon. The heat advisory this afternoon has been extended
through the night, and will be replaced with an Excessive Heat
Warning Friday morning.

Additionally, moderate winds and seas will create a moderate risk of
rip currents through the period at area beaches.

&&

.LONG TERM...
(Saturday through next Thursday)
Issued at 303 PM CDT Thu May 23 2024

Key Messages:

- Dangerous heat will continue through at least Tuesday, including
  Memorial Day Weekend.

- There will be an extreme risk of heat-related impacts,
  especially for those that do not stay hydrated or take frequent
  breaks in the shade/indoors.

- Moderate to high risk of rip currents will exist this holiday
  weekend.

Deep South Texas will remain under the influence of mid/upper
level ridging through early next week. Guidance continues to
indicate 850mb temperatures well above normal, ranging from
27-31C, which will allow for the already oppressive heat we`ve
experienced this week to further intensify. Triple-digit high
temperatures are forecast for most of Deep South Texas Saturday
through Tuesday, with the exception being along the Lower Texas
beaches and the immediate coast. High temperatures will be
greatest over the Rio Grande Plains, with highs reaching anywhere
from 107-110 degrees each afternoon. Despite high temperatures
closer to 100-105 degrees for the Rio Grande Valley and portions
of the Brush Country, the combination of hot temperatures and high
dew points will result in heat indices in the 113 to 120 degree
range. In addition, daily record high temperatures will likely be
tied or broken at Brownsville, McAllen, and Harlingen airports.

If the oppressive daytime heat was not enough, there really won`t
be much relief overnight as low temperatures only fall to around
79 degrees over the Northern Ranchlands and low 80s across the Rio
Grande Valley. In combination with the high dew points, especially
closer to the coast, heat indices at the start of the day will be
in the upper 80s and low 90s. Similar to record high temperatures,
daily record highest low temperatures will also be tied or broken.

This type of extreme heat will be very dangerous for anyone
spending time outside this weekend. Taking the necessary
precautions will be vital to reduce the risk of heat-related
illnesses. It is highly recommended to drink plenty of water,
even if you do not feel thirsty, take frequent breaks in the shade
or indoors, and wear light-colored, loose-fitting clothing.

There may be some relief from the heat by mid week as a weak cold
front approaches from Central Texas. This may bring some very
limited rain chances, and perhaps some increased cloud cover to
portions of Deep South Texas which will allow for slightly lower
afternoon temperatures.

&&

.AVIATION...
(18Z TAFS)
Issued at 1229 PM CDT Thu May 23 2024

Decreasing cloud cover looks to support VFR conditions at all
three TAF sites this afternoon. Gusty southeasterly winds will
continue in to the evening, with gusts dying out overnight. Some
MVFR conditions could return overnight as cloud cover thickens,
with the best likelihood for MVFR developing at HRL. VFR
conditions look to return after sunrise Friday morning.

&&

.MARINE...
Issued at 303 PM CDT Thu May 23 2024

This afternoon through Friday night...High pressure over the
Eastern Gulf and low pressure over Central Mexico will support
higher winds and seas this afternoon. A Small Craft Advisory is in
effect until 7pm this evening. Winds are expected to decrease
slightly tonight, however Small Craft Exercise Caution headlines
will likely be needed through the period.

Saturday through next Thursday...An enhanced pressure gradient
will result in moderate to breezy winds and moderate seas this
weekend. Small Craft Exercise Caution will likely continue through
the weekend, before becoming more favorable early next week.

&&

.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE             82  99  81 101 /   0   0   0   0
HARLINGEN               79 100  79 100 /   0   0   0   0
MCALLEN                 81 102  80 102 /   0   0   0   0
RIO GRANDE CITY         80 106  79 106 /   0   0   0   0
SOUTH PADRE ISLAND      82  88  82  91 /   0   0   0   0
BAYVIEW/PORT ISABEL     80  94  79  95 /   0   0   0   0

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...Heat Advisory until 7 PM CDT this evening for TXZ248>255-351-
     353>355.

GM...Small Craft Advisory until 7 PM CDT this evening for GMZ130-132-
     135-150-155.

&&

$$

SHORT TERM...60-BE
LONG TERM....22-Garcia
AVIATION...60-BE