Grand Rapids, MI weather in September
Expect mild weather with frequent rain in Grand Rapids in September, with highs near 74°F and lows near 53°F. Rain falls on about 10 days. Good for outdoor plans.
- Normal high
- 74°F
- Normal low
- 53°F
- Wet days
- 10
- 3.4 in total
- Muggy days
- 3
- dew point 65°F+
How September changes from start to finish
| September 1 | September 30 | |
|---|---|---|
| Normal high | 79°F | 68°F |
| Normal low | 58°F | 48°F |
| Chance of a wet day | 33% | 37% |
| Sunrise / sunset | 7:07 am / 8:18 pm | 7:38 am / 7:26 pm |
| Daylight | 13.2 h | 11.8 h |
Chance of a wet day: average for the first and last 7 days of the month. Times are local clock time (Eastern Time).
A typical September day
- 6 am56°Fdew point 52°F
- 9 am62°Fdew point 55°F
- Noon69°Fdew point 54°F
- 3 pm72°Fdew point 53°F
- 6 pm69°Fdew point 54°F
- 9 pm62°Fdew point 54°F
NOAA hourly normals (local standard time) from Grand Rapids (8 mi away); average wind 8 mph; clear or few clouds in 38% of daytime hours, mostly cloudy or overcast in 47%.
What kind of days to expect
- Comfortable dayshigh 65-80°F and dew point under 60°F16 of 30
- Hot dayshigh 90°F or more1 of 30
- Muggy daysdaily mean dew point 65°F or more3 of 30
- Wet daysat least 0.01 in of rain or melted snow10 of 30
- Notable rainat least 0.10 in6 of 30
- Freezing nightslow 32°F or below0 of 30
- Snow on the groundsnow depth 1 in or more0 of 30
Average days per September, counted from daily records for each year 1991-2020.
Rain in September
Normal precipitation is 3.4 in; a dry September brings about 2.0 in and a wet one about 4.6 in (25th and 75th percentiles). About 2 days bring half an inch or more, and about 1 an inch or more.
How September varies from year to year
- Warmest September, 1991-20202017: average high 79°F
- Coolest September1993: average high 65°F
- Wettest September2008: 9.5 in
- Driest September2017: 0.7 in
- Highest reading96°F (September 23, 2017)
- Lowest reading27°F (September 28, 1991)
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 | 81°F | 74°F | 61°F |
| Normal low | 61°F | 53°F | 42°F |
| Wet days | 10 | 10 | 13 |
| Comfortable days | 10 | 16 | 9 |
| Daylight | 13.9 h | 12.5 h | 11.0 h |
Highs change by -7°F from August and -13°F into October.
Nearby alternatives in September
- Warmer: Dayton, OH234 mi · high 79°F · 8 wet days
- Drier: Carmel, IN208 mi · high 77°F · 7 wet days
- Cooler: Sister Bay, WI170 mi · high 68°F · 10 wet days
How Grand Rapids ranks in September
- Normal high301st warmest of 378 cities; 5th of 8 in Michigan
- Wet days319th driest of 378
- Comfortable days56th most of 342
What to pack for Grand Rapids in September
- A rain jacket or umbrella – rain on about 10 days
Heating and cooling
September has 119 heating degree days and 73 cooling degree days (base 65°F), 3% of the year's total heating and cooling demand.
Questions
How hot is Grand Rapids in September?
The normal high is 74°F and the normal low is 53°F. From 1991 to 2020 the hottest September reading was 96°F (September 23, 2017).
Does it rain a lot in Grand Rapids in September?
About 10 days in September have at least 0.01 in of precipitation, and the normal total is 3.4 in. The wettest September in 1991-2020 was in 2008 (9.5 in); the driest was in 2017 (0.7 in).
Is September a good time to visit Grand Rapids?
September ranks 3rd of 12 months on our comfort score for Grand Rapids (69 out of 100). It has about 16 comfortable days and about 1 day at 90°F or hotter. The best months are May, June and September.
Where the numbers come from
- Temperature, rain, snowfall, snow depth, frost dates and humidity and wind by hour: Grand Rapids (USW00094860), 7.9 mi SE of the city center, 778 ft (138 ft higher than the city). NOAA normals and daily records, 1991-2020.
- Cloud cover: Lansing Capital City Airport (USW00014836), 57 mi ESE of the city center, 841 ft (201 ft higher than the city). NOAA normals and daily records, 1991-2020.
- Daily humidity and wind: Gerald R Ford International Airport (726350-94860), 9.2 mi SE of the city center, 788 ft (148 ft higher than the city). Hourly observations, 1991-2020.