Mcallen, TX 78505 Weather

Key Messages

Updated at 1045 PM CDT Tue Oct 20 2026

- Showers and thunderstorms over the Gulf moving inland will bring low to moderate (20-50%) rain chances primarily east of US-281 today, and across Deep South Texas into Thursday.

- Narrow beaches around high tide are possible today.

- Overall seasonable temperatures and pleasant weather expected this weekend.

- Rain chances return early next week as a mid-level trough approaches the area.

Discussion

Issued at 1045 PM CDT Tue Oct 20 2026

Rain chances increase through Wednesday morning as deep moisture interacts with coastal troughing offshore. Isolated showers over the Gulf waters will continue to move west-southwest, bringing isolated showers to the coast. As moisture encroaches westward, isolated to scattered showers and thunderstorms are expected to move inland late Wednesday morning through Wednesday afternoon. Shower coverage should diminish as it travels inland, with moderate PoPs (40-70%) focused east of US-281, highest along the coast. Isolated showers will continue working their way inland Wednesday night into Thursday. Rainfall amounts should generally be less than a half an inch, but isolated higher amounts to 2 inches are possible under heavier showers. Rain chances diminish Friday through the weekend bar afternoon sea breeze showers, before increasing again early next week ahead of an approaching trough.

High pressure over NE Mexico will return fair weather Friday into the weekend, with isolated sea breeze showers possible in the afternoons. Temperatures remain seasonable with highs in the upper 80s and lows in the 60s to low 70s.

Long-period swell and northeast winds will keep local beaches narrow. Minor coastal flooding is possible near high tide. Current guidance keeps water levels below minor flooding thresholds, but conditions will continue to be monitored.

Aviation

(00Z TAFS) Issued at 620 PM CDT Tue Oct 20 2026

VFR conditions should prevail through Wednesday morning, with northerly winds around 5 knots overnight. Wednesday afternoon, there is a chance for isolated to scattered showers moving inland from the coast. There is a low to moderate chance (30-50%) of showers impacting BRO and HRL, denoted by PROB30 groups. There is a less than 30% chance of showers at MFE during this timeframe as coverage should reduce as showers move inland. Any heavier showers passing over an airfield may reduce visibility and ceiling heights to MVFR or lower.

Marine

Issued at 1045 PM CDT Tue Oct 20 2026

Lingering moderate seas will result in intermittent SCEC conditions on the Gulf today. There is a medium to high (40-80%) chance of rain Wednesday and Wednesday night as a coastal trough interacts with deep moisture. Thursday and Friday, conditions improve as seas decrease to slight. Gentle to fresh onshore winds will continue through the week. This weekend, conditions may deteriorate yet again ahead of an approaching trough.