textproduct: Brownsville/Rio Grande Valley

KEY MESSAGES

Updated at 135 PM CDT Thu Oct 8 2026

- Low to medium (20-40%) rain chances continue this afternoon and evening. Low rain chances (around 20%) continue tomorrow along the immediate coast.

- Increasing concern for hazardous beach and marine conditions late this week and into the weekend as Hurricane Isaias moves towards the northern Gulf coast. Coastal flooding, dangerous surf, life-threatening rip currents, and rough seas are likely along the lower Texas beaches and Gulf waters.

- Mostly minor risks of heat-related illnesses (level 1/4) become moderate (level 2/4) by next Monday as deep low-level moisture returns.

DISCUSSION

Issued at 135 PM CDT Thu Oct 8 2026

Our period of unsettled weather and mostly beneficial rainfall has finally come to an end along the immediate coast, with only brief isolated showers developing from northeast to southwest across portions of the region expected through tomorrow afternoon. As moisture content continues to drop and subsidence builds, we should continue to see generally rain-free conditions through next week. The exception will be if any isolated sea breeze activity develops, but chances remain fairly low each day. Otherwise, expect seasonable temperatures in the low to mid 90s each afternoon. Lower humidity will keep heat indices in the 90s through the weekend, but as the humidity becomes elevated, we may start to see triple-digit heat indices by early next week.

For the Columbus Day holiday weekend, our attention will turn to the hazardous beach and marine conditions expected as Hurricane Isaias continues its course across the Gulf waters towards the northern Gulf coast. Increasing swell will bring hazardous beach conditions, including life-threatening rip currents, high surf, and coastal flooding. Tidal runup is likely along the beach, especially around periods of high tide and runup will likely reach the dunes along narrower beaches. Coastal Flood Advisories, High Surf Advisories, and/or High Risk of Rip Current Statements are likely as early as tomorrow and continuing through much of the weekend.

AVIATION

(18Z TAFS) Issued at 135 PM CDT Thu Oct 8 2026

VFR will prevail through the forecast period with northerly to northeasterly winds. An isolated shower or two cannot be ruled out this afternoon, but should be fairly short lived. Winds will become fairly light to calm tonight. Some patchy fog cannot be ruled out given the clear skies, calm winds, and recent rains, but should remain well north and west of the terminals. Otherwise, expect winds to increase to around 10 knots by late tomorrow morning.

MARINE

Issued at 135 PM CDT Thu Oct 8 2026

Adverse to hazardous marine conditions will likely continue into the weekend as seas build in response to Hurricane Isaias as it travels north/northeast across the Gulf. This will result in Small Craft Advisories for portions of or all of the Gulf waters as seas increase upwards of 5-7 feet late this week and over the weekend. Conditions should begin to improve by late this weekend and early next week. Otherwise, isolated to scattered showers and thunderstorms cannot be ruled out through the end of the week, before decreasing this weekend.

PRELIMINARY POINT TEMPS/POPS

BROWNSVILLE 75 89 74 90 / 0 10 0 0 HARLINGEN 70 91 70 91 / 0 10 0 0 MCALLEN 73 93 72 93 / 0 0 0 0 RIO GRANDE CITY 71 93 69 93 / 10 0 0 0 SOUTH PADRE ISLAND 80 86 79 86 / 0 20 10 0 BAYVIEW/PORT ISABEL 76 87 74 88 / 0 20 0 0

BRO WATCHES/WARNINGS/ADVISORIES

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