Today | Weather | Monday, September 21, 2026

Active Weather Warnings

Special Weather Statement

Weather in Brownsville, Texas

05:46 PM

Now

91° F

Feels Like 97°

Precipitation 20 %

Wind 14 mph

UV Index (0 - 11+) 1

Humidity 59 %

Today

Day 99°

Night 77°

Precipitation 49 %

Wind 8 mph

UV Index (0 - 11+) 8

Warning: High UV Index Today: 8

High risk of harm from unprotected sun exposure. Take precautions: wear a hat, sunglasses, and apply sunscreen regularly if you’ll be outdoors for extended periods.

Brownsville Weather Forecast Updated

Last updated on September 21, 2026 at 4:25 PM

Weather Forecast History

Last Year's Weather on This Day (September 21, 2025)

Day

90°

Night

77°

Wind

6 mph

Precipitation

25 %

Air Quality in Brownsville

NOW

22 AQI

Good air quality Dominant pollutant: O₃

Pollutant Concentrations:

PM_2.5 0.99 µg/m³

PM₁₀ 2.19 µg/m³

O₃ 0.024 ppm

NO₂ 0.1 ppb

SO₂ 0 ppb

CO 0.09 ppm

NH₃ 0.28 µg/m³

NO 0.03 µg/m³

PM_2.5 – Fine particles <2.5μm

PM₁₀ – Inhalable particles <10μm

O₃ – Ozone

NO₂ – Nitrogen dioxide

SO₂ – Sulfur dioxide

CO – Carbon monoxide

NH₃ – Ammonia

NO – Nitric oxide

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

Show raw pollutant concentrations (µg/m³)

PM_2.5 – 0.99 µg/m³

PM₁₀ – 2.19 µg/m³

O₃ – 47.04 µg/m³

NO₂ – 0.23 µg/m³

SO₂ – 0.1 µg/m³

CO – 102.65 µg/m³

NH₃ – 0.28 µg/m³

NO – 0.03 µg/m³

View Hourly Air Quality Forecast

Weather Alerts and Warnings for Brownsville

Moderate Expected Observed

Special Weather Statement

Special Weather Statement issued September 21 at 6:23AM CDT by NWS Brownsville TX

Sep 21, 6:23 AM → Sep 21, 7:00 PM

The combination of hot temperatures and elevated humidity levels
will produce heat index values between 108 and 111 degrees for
several hours this afternoon into this evening. A few locations
may briefly experience heat index values above 111 degrees.

If you plan to spend time outside, drink plenty of water, wear
light weight and light colored clothing and take frequent breaks
from the heat. Young children and pets should never be left
unattended in vehicles.

Updated: Sep 21, 4:25 PM Source: NWS Alert