textproduct: Brownsville/Rio Grande Valley

KEY MESSAGES

Updated at 225 PM CDT Fri Jul 10 2026

- Low to medium (20-50%) rain chances this afternoon through the weekend from possible rounds of showers and thunderstorms.

- High moisture content could result in locally heavy rain. A few areas may receive up to an inch or more, most likely along/east of US-281/I-69 E.

- Afternoon heat indices around 100-105 F escalate to 105-110 F this weekend, bringing a moderate risk (level 2 of 4) of heat related illness.

- There is a moderate risk of rip currents through at least Saturday evening.

DISCUSSION

Issued at 225 PM CDT Fri Jul 10 2026

An unsettled weather pattern will continue through most of the weekend across Deep South Texas as an inverted trough continues to transport rich, Gulf moisture across the region. The 18Z sounding this afternoon observed a precipitable water value of 2.39 inches, which is upwards of the 90th percentile for early July. In combination with daytime heating, isolated to scattered showers and thunderstorms will continue to develop and track generally from south to north through the evening hours. There should be a lull in precipitation chances tonight. However, the latest suite of high res guidance indicates additional showers and isolated thunderstorms may approach the low/mid RGV by early Saturday morning, but should quickly move from south to north.

Expect low to medium (20-40%) rain chances across Deep South Texas through the weekend, mainly during the daytime hours. Given the presence of anomalously high moisture content, any showers and thunderstorms will be capable of locally heavy rainfall, which may result in minor or nuisance flooding. An isolated 1-2 inches of rain cannot be ruled out, especially with any training activity. Otherwise, strong thunderstorms with a primary threat for gusty winds and perhaps some small hail cannot be ruled out. On Sunday, any activity looks to be more confined to the sea breeze during the late morning into the early afternoon hours.

Precipitation chances should come to an end by the start of the work week as riding aloft builds and subsidence increases. Isolated sea breeze activity cannot be ruled out, but chances remain fairly low (10% or less). Seasonably hot temperatures will continue through the first half of July, with highs in the mid to upper 90s each afternoon. Heat index values will range from 100-110 degrees.

AVIATION

(18Z TAFS) Issued at 225 PM CDT Fri Jul 10 2026

VFR/MVFR ceilings are expected through the forecast period with southeasterly winds generally around 10 to 15 knots and occasionally higher gusts. Isolated to scattered convection will continue through the afternoon hours, but should come to an end with the loss of daytime heating. Most guidance keeps the region generally rain-free tonight, but another round of isolated to scattered convection is possible once again tomorrow.

MARINE

Issued at 225 PM CDT Fri Jul 10 2026

Generally favorable marine conditions will prevail through next week, with moderate southeasterly winds and slight seas. Low to medium rain chances (20-40%) continue into the weekend before decreasing to below 10% next week. Locally enhanced winds and seas are expected within any showers and thunderstorms.

PRELIMINARY POINT TEMPS/POPS

BROWNSVILLE 80 94 81 94 / 20 20 10 10 HARLINGEN 77 95 78 96 / 0 20 10 20 MCALLEN 80 98 80 99 / 0 20 0 20 RIO GRANDE CITY 78 98 78 99 / 10 40 10 20 SOUTH PADRE ISLAND 81 88 82 88 / 30 10 10 10 BAYVIEW/PORT ISABEL 79 92 80 93 / 20 10 10 10

BRO WATCHES/WARNINGS/ADVISORIES

TX...None. GM...None.