172
FXUS64 KBRO 161805
AFDBRO

Area Forecast Discussion
National Weather Service Brownsville TX
105 PM CDT Mon Jun 16 2025

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

.KEY MESSAGES...
Updated at 1226 PM CDT Mon Jun 16 2025

 - Coastal showers and storms bring heavy rain this afternoon

 - Moderate Heat Risk through Wednesday

 - Marginal Risk (1 of 3) of Excessive Rainfall late this week

&&

.SHORT TERM...
(Tonight through Wednesday night)
Issued at 1226 PM CDT Mon Jun 16 2025

Visible satellite imagery and this mornings` RAOB shows opposing
flow at the surface and aloft. Moist southerly flow is allowing
for pop-up showers and along both outflow and seabreeze boundaries
east of I-69C, sheared off from the northerly flow aloft. This is
keeping storms sub-severe, however, it does little to encourage
storm motion. Slow moving, training showers and storms bringing
heavy rainfall (thanks to an anomalously moist atmosphere... 12Z
Sounding PWATs of 2.02") leave concern for flooding. Flood
Advisories are in place this afternoon for portions of Kenedy,
Willacy, and Hidalgo counties, and continue to be monitored.

Showers and thunderstorms should diminish late this afternoon.
Through mid-week, low chances of precipitation will continue bar
the chance of seabreeze activity in the afternoons. Ridging aloft
transiting into central CONUS will support dry air advection into
the mid-layers, limiting moisture depth. Near-normal temperatures
exist, but low-level moisture will maintain heat indices in the
triple digits just shy of Heat Advisory criteria.

&&

.LONG TERM...
(Thursday through next Monday)
Issued at 1226 PM CDT Mon Jun 16 2025

As the aforementioned ridge progresses over ECONUS, southerly
flow in the midlevels will return deeper tropical moisture and
bring anomalously high PWATs (greater than 90th percentile of
climatology) to the region. This predominately southerly flow will
bring moderate to high (50-80%) chances for showers and
thunderstorms Thursday afternoon/evening through Friday. Highest
PoPs exist along the coast. Chances of rain decrease to moderate
CWA-wide over the weekend. WPC has placed Cameron, eastern
Hidalgo, and southern/eastern Willacy counties in a Marginal Risk
(level 1 of 3) for excessive rainfall on Thursday and Friday.
Deep moisture content will likely support continued chances of
excessive rainfall through the weekend.

Increased rain chances and cloud cover will leave high and low
temperatures below average.

&&

.AVIATION...
(18Z TAFS)
Issued at 1226 PM CDT Mon Jun 16 2025

Showers and thunderstorms in the vicinity of all sites creating
temporary IFR/MVFR conditions will persist through the afternoon as
pop-up showers and thunderstorms form along a seabreeze and outflow
boundary. Conditions within any showers or storms may cause low
visibility and gustier conditions. Tonight, primarily VFR conditions
prevail with southerly winds.

&&

.MARINE...
Issued at 1226 PM CDT Mon Jun 16 2025

Moderate southerly flow through midweek will increase seas to around
4 feet, leading to possible necessity of Small Craft Exercise
Caution headlines. Winds subside and remain south-southeasterly,
maintaining slight seas for the remainder of the period. There is
a moderate to high chance (50-80%) of showers and thunderstorms
late this week starting Thursday continuing through the weekend.
Conditions will be degraded within showers and thunderstorms.

&&

.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE             79  94  80  94 /  10  10   0  10
HARLINGEN               77  97  78  96 /  10  10   0  10
MCALLEN                 79 101  79 100 /  10   0   0   0
RIO GRANDE CITY         76 100  77 100 /  10   0   0   0
SOUTH PADRE ISLAND      81  88  81  88 /  10  10   0  10
BAYVIEW/PORT ISABEL     78  93  79  92 /  10  10   0  10

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...None.
&&

$$

SHORT TERM...69-HK
LONG TERM....69-HK
AVIATION...69-HK