McAllen, TX weather in September
McAllen is hot and oppressively humid in September, with some rain: highs average 94°F and nights drop to about 76°F. There are about 8 days with rain. Midday heat is the main thing to plan around.
- Normal high
- 94°F
- Normal low
- 76°F
- Wet days
- 8
- 4.6 in total
- Muggy days
- 27
- dew point 65°F+
How September changes from start to finish
| September 1 | September 30 | |
|---|---|---|
| Normal high | 97°F | 92°F |
| Normal low | 78°F | 73°F |
| Chance of a wet day | 25% | 23% |
| Sunrise / sunset | 7:12 am / 7:52 pm | 7:24 am / 7:20 pm |
| Daylight | 12.7 h | 11.9 h |
Chance of a wet day: average for the first and last 7 days of the month. Times are local clock time (Central Time).
A typical September day
- 6 am75°Fdew point 72°F
- 9 am82°Fdew point 73°F
- Noon89°Fdew point 70°F
- 3 pm91°Fdew point 69°F
- 6 pm87°Fdew point 70°F
- 9 pm81°Fdew point 72°F
NOAA hourly normals (local standard time) from Mcallen Miller Intl Airport (2 mi away); average wind 8 mph; clear or few clouds in 63% of daytime hours, mostly cloudy or overcast in 21%.
What kind of days to expect
- Comfortable dayshigh 65-80°F and dew point under 60°F0 of 30
- Hot dayshigh 90°F or more24 of 30
- Muggy daysdaily mean dew point 65°F or more27 of 30
- Wet daysat least 0.01 in of rain or melted snow8 of 30
- Notable rainat least 0.10 in6 of 30
- Freezing nightslow 32°F or below0 of 30
Average days per September, counted from daily records for each year 1991-2020.
Rain in September
Normal precipitation is 4.6 in; a dry September brings about 2.5 in and a wet one about 5.4 in (25th and 75th percentiles). About 3 days bring half an inch or more, and about 2 an inch or more.
How September varies from year to year
- Warmest September, 1991-20202016: average high 100°F
- Coolest September1991: average high 90°F
- Wettest September2014: 11.2 in
- Driest September2011: no measurable precipitation
- Highest reading108°F (September 4, 2011)
- Lowest reading54°F (September 30, 2020)
From the station's daily records with NOAA quality flags removed; most recent date shown when a reading repeats.
September compared with August and October
| August | September | October | |
|---|---|---|---|
| Normal high | 100°F | 94°F | 89°F |
| Normal low | 79°F | 76°F | 69°F |
| Wet days | 5 | 8 | 6 |
| Comfortable days | 0 | 0 | 2 |
| Daylight | 13.0 h | 12.3 h | 11.5 h |
Highs change by -6°F from August and -5°F into October.
Nearby alternatives in September
- Cooler: South Padre Island, TX66 mi · high 89°F · 11 wet days
How McAllen ranks in September
- Normal high14th warmest of 378 cities; 2nd of 38 in Texas
- Wet days200th driest of 378
- Comfortable days312th most of 342
What to pack for McAllen in September
- Light, breathable clothing – highs near 94°F and about 27 muggy days
- A rain jacket or umbrella – rain on about 8 days
Heating and cooling
September has 0 heating degree days and 599 cooling degree days (base 65°F), 11% of the year's total heating and cooling demand.
Questions
How hot is McAllen in September?
The normal high is 94°F and the normal low is 76°F. From 1991 to 2020 the hottest September reading was 108°F (September 4, 2011).
Does it rain a lot in McAllen in September?
About 8 days in September have at least 0.01 in of precipitation, and the normal total is 4.6 in. The wettest September in 1991-2020 was in 2014 (11.2 in); the driest was in 2011, with no measurable precipitation.
Is September a good time to visit McAllen?
September ranks 12th of 12 months on our comfort score for McAllen (33 out of 100). It has almost no comfortable days and about 24 days at 90°F or hotter. The best months are January and December.
Where the numbers come from
- Temperature, rain, frost dates, humidity and wind by hour and cloud cover: Mcallen Miller Intl Airport (USW00012959), 2.0 mi SW of the city center, 100 ft . NOAA normals and daily records, 1991-2020.
- Snowfall and snow depth: Mcallen (USC00415701), 1.5 mi WSW of the city center, 100 ft . NOAA normals and daily records, 1991-2020.
- Daily humidity and wind: Mc Allen Miller Intl Arpt (722506-12959), 1.9 mi SSW of the city center, 99 ft . Hourly observations, 1991-2020.