Olathe weather in September: Olathe, Kansas: normal highs, lows, rain and records for September
Olathe in September has a normal high of 78°F and a normal low of 59°F, a daily mean of 68°F, falling from 83°F on the 1st to 73°F by the 30th. Measurable precipitation falls on 8 days in a normal September, 3.54 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 26°C and low of 15°C, 90 mm of precipitation in September.
- NOAA stationOlathe Johnson County Exec Airport
- Station IDUSW00003967
- Location38.85°N 94.74°W
- Elevation1,070 ft (326 m)
- Population149,035
- Jan 39° 21°
- Feb 44° 25°
- Mar 55° 35°
- Apr 65° 45°
- May 74° 55°
- Jun 83° 65°
- Jul 88° 69°
- Aug 87° 67°
- Sep 78° 59°
- Oct 67° 47°
- Nov 53° 35°
- Dec 42° 25°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Olathe in September?
The normal high is 78°F and the normal low 59°F, for a daily mean of 68.4°F. September is 8.6°F cooler than August and 11.7°F warmer than October. September is the 4th warmest month of the year in Olathe and the 6th wettest. Across the month the normal high falls 10°F, from 83°F on September 1 to 73°F on September 30. From one year to the next September's mean temperature typically moves about 3.0°F either way (NOAA's standard deviation), so roughly two Septembers in three average between 65°F and 71°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 29%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| September 1 | 83°F | 64°F | 29% | 18% |
| September 8 | 81°F | 61°F | 29% | 18% |
| September 15 | 78°F | 59°F | 29% | 18% |
| September 22 | 76°F | 56°F | 29% | 18% |
| September 30 | 73°F | 53°F | 28% | 18% |
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 | 83°F | 64°F | 29% | 18% | 13 h |
| September 2 | 83°F | 63°F | 29% | 18% | 13 h |
| September 3 | 83°F | 63°F | 29% | 18% | 13 h |
| September 4 | 82°F | 63°F | 29% | 18% | 13 h |
| September 5 | 82°F | 62°F | 29% | 18% | 12 h 50 min |
| September 6 | 82°F | 62°F | 29% | 18% | 12 h 50 min |
| September 7 | 81°F | 62°F | 29% | 18% | 12 h 50 min |
| September 8 | 81°F | 61°F | 29% | 18% | 12 h 50 min |
| September 9 | 81°F | 61°F | 29% | 18% | 12 h 50 min |
| September 10 | 80°F | 61°F | 29% | 18% | 12 h 40 min |
| September 11 | 80°F | 60°F | 29% | 18% | 12 h 40 min |
| September 12 | 79°F | 60°F | 29% | 18% | 12 h 40 min |
| September 13 | 79°F | 60°F | 29% | 18% | 12 h 40 min |
| September 14 | 79°F | 59°F | 29% | 18% | 12 h 30 min |
| September 15 | 78°F | 59°F | 29% | 18% | 12 h 30 min |
| September 16 | 78°F | 59°F | 29% | 18% | 12 h 30 min |
| September 17 | 78°F | 58°F | 29% | 18% | 12 h 30 min |
| September 18 | 77°F | 58°F | 29% | 18% | 12 h 20 min |
| September 19 | 77°F | 57°F | 29% | 18% | 12 h 20 min |
| September 20 | 77°F | 57°F | 29% | 18% | 12 h 20 min |
| September 21 | 76°F | 57°F | 29% | 18% | 12 h 20 min |
| September 22 | 76°F | 56°F | 29% | 18% | 12 h 10 min |
| September 23 | 75°F | 56°F | 29% | 18% | 12 h 10 min |
| September 24 | 75°F | 56°F | 28% | 18% | 12 h 10 min |
| September 25 | 75°F | 55°F | 28% | 18% | 12 h 10 min |
| September 26 | 74°F | 55°F | 28% | 18% | 12 h |
| September 27 | 74°F | 54°F | 28% | 18% | 12 h |
| September 28 | 74°F | 54°F | 28% | 18% | 12 h |
| September 29 | 73°F | 54°F | 28% | 18% | 12 h |
| September 30 | 73°F | 53°F | 28% | 18% | 11 h 50 min |
- Normal high
- 78°FSeptember average
- Normal low
- 59°FSeptember average
- Precipitation
- 3.54 inmonth total
- Days with precipitation
- 80.01 inch or more
- Days at 90°F or more
- 3
- Daylight
- 13 h to 11 h 50 minSeptember 1 to September 30
- Days at 70°F or more
- 27
- Days at 80°F or more
- 16
- Sunshine
- 82%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00003967; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in Olathe in September?
On a given September day the chance of 0.01 inch or more is 29% on average, highest around September 1 (29%). In all, 3.54 in falls on 8 days of a normal September, 1 of them with an inch or more.
In a normal September in Olathe, 3 days reach 90°F.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00003967.
What are the records for September in Olathe?
The warmest September temperature on this station's record (since 1996) is 105°F, on September 2, 2000; the coldest is 38°F, on September 13, 2014. The wettest September brought 9.54 in (1998).
The September mean against the 1991-2020 normal of 68.4°F: 2021 72.8°F (+4.4), 2022 71.3°F (+2.9), 2023 73.6°F (+5.2), 2024 70.9°F (+2.5), 2025 71.3°F (+2.9), 2026 77.0°F (+8.6). 6 of 6 ran warmer than normal.
| September | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 72.8°F | +4.4°F | 2.93 in |
| 2022 | 71.3°F | +2.9°F | 0.42 in |
| 2023 | 73.6°F | +5.2°F | 4.80 in |
| 2024 | 70.9°F | +2.5°F | 1.96 in |
| 2025 | 71.3°F | +2.9°F | 1.73 in |
| 2026 | 77.0°F | +8.6°F | – |
Source: records: ACIS, station USW00003967; recent months: ACIS, station USW00003967. Records and recent months use complete months only.
How does September in Olathe compare across Kansas?
Across the 137 places PlainClimate covers in Kansas, September normal highs run from 78°F in Bonner Springs to 86°F in Sublette; Olathe's is 78°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.