Port Isabel (TX) Weather & Climate: Best Time to Visit
Average temperatures, rainfall, sunshine and the best time to visit Port Isabel.
Climate overview of Port Isabel
Port Isabel, Texas, United States of America, experiences significant temperature variation throughout the year. Summers bring daytime highs of 33°C (91°F) in August, while winters cool to 20°C (68°F) in January.
Annual rainfall is moderate at around 687 mm (27 in), with September being the wettest month. The city also has a distinct dry season from February to April, with very warm summers and pleasant winters. The sunniest month is July, with 10.9 hours of sunshine per day on average.
Port Isabel Weather by Month
Pick a month to see the average temperature, rainfall and sunshine in Port Isabel - and find the best time to visit.
Monthly Temperature in Port Isabel
Depending on the time of the year, temperatures range from very warm to pleasant in Port Isabel. Average daytime temperatures reach a very warm 33°C (91°F) in August. In January, the coolest month of the year, temperatures drop to a pleasant 20°C (68°F).
At night, temperatures range from around 26°C (79°F) in August to 12°C (54°F) in January.
Check out our detailed temperature page for more information.
Temperature ranges by month
Rainfall in Port Isabel
Generally, Port Isabel has a moderate amount of precipitation, averaging 687 mm (27 in) of rainfall annually. Port Isabel can be quite wet during September, receiving approximately 171 mm (6.7 in) of precipitation over 14 rainy days.
In contrast, during the driest month (August), you will experience much drier conditions, with 25 mm (1 in) of precipitation spread across 6 rainy days. For more details, please visit our Port Isabel Precipitation page.
The mean monthly precipitation over the year, including rain, hail, and snow
The average number of days each month with precipitation
Sunshine Hours in Port Isabel
Port Isabel can be enjoyed more throughout the sunniest month of July under a blue sky, with approximately 10.9 hours of sunshine daily. In contrast, the city experiences much darker days in January, with only 4.4 hours of sunlight per day.
Visit our detailed sunshine hours page for more information.
Monthly hours of sunshine
Daily hours of sunshine
Daily percentage of sunshine
Humidity in Port Isabel by Month
The relative humidity is high throughout the year in Port Isabel.
The city experiences its highest humidity in January, reaching 78%. In July, the humidity drops to its lowest level at 73%. What does this mean? Read our detailed page on humidity levels for further details.
Relative humidity over the year
Best Time to Visit Port Isabel
Monthly ratings reflect general weather comfort, based on daytime temperature and rainfall. Swimming and winter conditions are highlighted separately where relevant.
- Best overall: January, February, March, April, October, November and December
- Warmest weather: June, July, August and September
- Most sunshine: July
- Fewer rainy days: February, March, April, May and August
- Wettest months: September and October, when rainfall is highest.
- Seasonal pattern: A distinct dry season from February to April, with very warm summers and pleasant winters
Frequently asked questions about the climate in Port Isabel
What is the best time to visit Port Isabel?
January, February, March, April, October, November and December typically offer the most optimal weather in Port Isabel. In contrast, September tends to have less optimal conditions. Port Isabel has a distinct dry season from February to April, with very warm summers and pleasant winters.
What temperatures can I expect in Port Isabel?
Daytime highs range from 20°C (68°F) in January to 33°C (91°F) in August. Nighttime lows range from 12°C (54°F) to 26°C (79°F). Temperatures vary considerably through the year.
How much rain does Port Isabel get?
Annual rainfall is around 687 mm (27 in). September is the wettest month with 171 mm (6.7 in), while August is the driest with 25 mm (1 in).
How sunny is Port Isabel?
Port Isabel receives around 2,715 hours of sunshine per year. July is the sunniest month with 326 hours, while January is the cloudiest with just 133 hours. Overall, Port Isabel enjoys abundant sunshine.
Port Isabel 3-Day Forecast
Port Isabel on the map
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