Houston weather in September: Houston, Texas: normal highs, lows, rain and records for September
Houston in September has a normal high of 90°F and a normal low of 71°F, a daily mean of 81°F, falling from 93°F on the 1st to 88°F by the 30th. Measurable precipitation falls on 8 days in a normal September, 4.71 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 32°C and low of 21°C, 120 mm of precipitation in September.
- NOAA stationHouston Intercontinental Airport
- Station IDUSW00012960
- Location29.98°N 95.36°W
- Elevation95 ft (29 m)
- From the center14 miles
- Population2,390,125
- Jan 64° 44°
- Feb 68° 48°
- Mar 74° 54°
- Apr 80° 60°
- May 87° 68°
- Jun 92° 74°
- Jul 95° 76°
- Aug 95° 75°
- Sep 90° 71°
- Oct 83° 61°
- Nov 73° 52°
- Dec 65° 46°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Houston in September?
The normal high is 90°F and the normal low 71°F, for a daily mean of 80.5°F. September is 4.7°F cooler than August and 8.7°F warmer than October. September is the 4th warmest month of the year in Houston and the 5th wettest. Across the month the normal high falls 5°F, from 93°F on September 1 to 88°F on September 30. From one year to the next September's mean temperature typically moves about 1.7°F either way (NOAA's standard deviation), so roughly two Septembers in three average between 79°F and 82°F.
Bars above: each day's normal high to low. Columns below: the chance of 0.01 inch or more of precipitation that day, on a scale of 0 to 100% (highest 31%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| September 1 | 93°F | 74°F | 31% | 21% |
| September 8 | 92°F | 73°F | 30% | 21% |
| September 15 | 91°F | 71°F | 28% | 19% |
| September 22 | 89°F | 69°F | 26% | 18% |
| September 30 | 88°F | 67°F | 24% | 16% |
Every day of September: normal high, low and chance of precipitation (warmest afternoon September 1, coldest night September 30)
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in | Daylight |
|---|---|---|---|---|---|
| September 1 | 93°F | 74°F | 31% | 21% | 12 h 50 min |
| September 2 | 93°F | 74°F | 31% | 21% | 12 h 50 min |
| September 3 | 93°F | 74°F | 30% | 21% | 12 h 40 min |
| September 4 | 93°F | 73°F | 30% | 21% | 12 h 40 min |
| September 5 | 92°F | 73°F | 30% | 21% | 12 h 40 min |
| September 6 | 92°F | 73°F | 30% | 21% | 12 h 40 min |
| September 7 | 92°F | 73°F | 30% | 21% | 12 h 40 min |
| September 8 | 92°F | 73°F | 30% | 21% | 12 h 40 min |
| September 9 | 92°F | 72°F | 30% | 21% | 12 h 30 min |
| September 10 | 92°F | 72°F | 29% | 20% | 12 h 30 min |
| September 11 | 91°F | 72°F | 29% | 20% | 12 h 30 min |
| September 12 | 91°F | 72°F | 29% | 20% | 12 h 30 min |
| September 13 | 91°F | 72°F | 29% | 20% | 12 h 30 min |
| September 14 | 91°F | 71°F | 28% | 20% | 12 h 20 min |
| September 15 | 91°F | 71°F | 28% | 19% | 12 h 20 min |
| September 16 | 90°F | 71°F | 28% | 19% | 12 h 20 min |
| September 17 | 90°F | 70°F | 28% | 19% | 12 h 20 min |
| September 18 | 90°F | 70°F | 27% | 19% | 12 h 20 min |
| September 19 | 90°F | 70°F | 27% | 19% | 12 h 20 min |
| September 20 | 90°F | 70°F | 27% | 18% | 12 h 10 min |
| September 21 | 89°F | 69°F | 27% | 18% | 12 h 10 min |
| September 22 | 89°F | 69°F | 26% | 18% | 12 h 10 min |
| September 23 | 89°F | 69°F | 26% | 18% | 12 h 10 min |
| September 24 | 89°F | 68°F | 26% | 18% | 12 h 10 min |
| September 25 | 89°F | 68°F | 25% | 17% | 12 h 10 min |
| September 26 | 88°F | 68°F | 25% | 17% | 12 h |
| September 27 | 88°F | 67°F | 25% | 17% | 12 h |
| September 28 | 88°F | 67°F | 25% | 17% | 12 h |
| September 29 | 88°F | 67°F | 25% | 17% | 12 h |
| September 30 | 88°F | 67°F | 24% | 16% | 12 h |
- Normal high
- 90°FSeptember average
- Normal low
- 71°FSeptember average
- Precipitation
- 4.71 inmonth total
- Days with precipitation
- 80.01 inch or more
- Days at 90°F or more
- 18
- Daylight
- 12 h 50 min to 12 hSeptember 1 to September 30
- Days at 70°F or more
- 30
- Days at 80°F or more
- 29
- Sunshine
- 80%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00012960; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in Houston in September?
On a given September day the chance of 0.01 inch or more is 28% on average, highest around September 1 (31%). In all, 4.71 in falls on 8 days of a normal September, 1 of them with an inch or more.
In a normal September in Houston, 18 days reach 90°F.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00012960.
How humid and windy is Houston in September?
At 3 p.m. the normal temperature is 85°F with 47% relative humidity and a dew point of 63°F; at 6 a.m. it is 67°F with 89% humidity. The wind averages 6.3 mph, most often from the east-northeast in the afternoon.
| Time | Temperature | Dew point | Humidity | Wind | Clear or few clouds |
|---|---|---|---|---|---|
| 6 a.m. | 67°F | 64°F | 89% | 4.0 mph | 50% |
| 9 a.m. | 76°F | 66°F | 71% | 7.5 mph | 49% |
| noon | 83°F | 64°F | 53% | 8.8 mph | 32% |
| 3 p.m. | 85°F | 63°F | 47% | 9.4 mph | 33% |
| 6 p.m. | 80°F | 64°F | 60% | 8.4 mph | 41% |
| 9 p.m. | 73°F | 66°F | 77% | 5.3 mph | 58% |
Source: NOAA NCEI 1991-2020 hourly normals, station USW00012960. Hourly normals exist only for NOAA's first-order stations; a dash where NOAA publishes no value for that hour (the sky at some hours).
What are the records for September in Houston?
The warmest September temperature on Houston's official record (since 1888) is 109°F, on September 4, 2000; the coldest is 45°F, on September 27, 1942. The wettest September brought 14.95 in (2019).
The September mean against the 1991-2020 normal of 80.5°F: 2021 79.5°F (−1.0), 2022 80.7°F (+0.2), 2023 85.3°F (+4.8), 2024 82.7°F (+2.2), 2025 81.7°F (+1.2), 2026 84.8°F (+4.3). 5 of 6 ran warmer than normal.
| September | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 79.5°F | −1.0°F | 8.73 in |
| 2022 | 80.7°F | +0.2°F | 0.75 in |
| 2023 | 85.3°F | +4.8°F | 2.77 in |
| 2024 | 82.7°F | +2.2°F | 2.53 in |
| 2025 | 81.7°F | +1.2°F | 1.21 in |
| 2026 | 84.8°F | +4.3°F | 0.91 in |
Source: records: ACIS, NWS threaded record IAHthr; recent months: ACIS, station USW00012960. Records and recent months use complete months only.
How does September in Houston compare across Texas?
Across the 321 places PlainClimate covers in Texas, September normal highs run from 81°F in Hart to 95°F in Presidio; Houston's is 90°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.