Climateby Month

Dearborn, MI weather in September

NOAA 1991-2020 normals and daily records · Dearborn all year

September in Dearborn: mild, with some rain. Highs 75°F, lows 53°F, about 10 days with rain. A good month for most outdoor plans.

Normal high
75°F
Normal low
53°F
Wet days
10
3.2 in total
Muggy days
3
dew point 65°F+

How September changes from start to finish

Normal values at the start and end of September
September 1September 30
Normal high80°F70°F
Normal low59°F48°F
Chance of a wet day31%32%
Sunrise / sunset6:58 am / 8:07 pm7:28 am / 7:16 pm
Daylight13.2 h11.8 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

  1. 6 am59°Fdew point 54°F
  2. 9 am65°Fdew point 55°F
  3. Noon71°Fdew point 54°F
  4. 3 pm73°Fdew point 54°F
  5. 6 pm70°Fdew point 54°F
  6. 9 pm65°Fdew point 55°F

NOAA hourly normals (local standard time) from Detroit City Airport (10 mi away); average wind 7 mph; clear or few clouds in 50% of daytime hours, mostly cloudy or overcast in 36%.

What kind of days to expect

  • Comfortable dayshigh 65-80°F and dew point under 60°F15 of 30
  • Hot dayshigh 90°F or more2 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 3.2 in; a dry September brings about 1.5 in and a wet one about 4.4 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, 1991-20202002: average high 83°F
  • Coolest September1993: average high 69°F
  • Wettest September2000: 6.7 in
  • Driest September1995: 0.6 in
  • Highest reading100°F (September 9, 2002)
  • Lowest reading29°F (September 23, 1995)

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

AugustSeptemberOctober
Normal high82°F75°F62°F
Normal low61°F53°F42°F
Wet days101011
Comfortable days71512
Daylight13.8 h12.5 h11.1 h

Highs change by -7°F from August and -13°F into October.

How Dearborn ranks in September

  • Normal high280th warmest of 378 cities; 2nd of 8 in Michigan
  • Wet days285th driest of 378
  • Comfortable days92nd most of 342

What to pack for Dearborn in September

  • A rain jacket or umbrella – rain on about 10 days

Heating and cooling

September has 106 heating degree days and 84 cooling degree days (base 65°F), 3% of the year's total heating and cooling demand.

Questions

How hot is Dearborn in September?

The normal high is 75°F and the normal low is 53°F. From 1991 to 2020 the hottest September reading was 100°F (September 9, 2002).

Does it rain a lot in Dearborn in September?

About 10 days in September have at least 0.01 in of precipitation, and the normal total is 3.2 in. The wettest September in 1991-2020 was in 2000 (6.7 in); the driest was in 1995 (0.6 in).

Is September a good time to visit Dearborn?

September ranks 3rd of 12 months on our comfort score for Dearborn (67 out of 100). It has about 15 comfortable days and about 2 days at 90°F or hotter. The best month is May.

Where the numbers come from

  • Temperature and frost dates: Dearborn (USC00202015), 3.1 mi W of the city center, 605 ft . NOAA normals and daily records, 1991-2020.
  • Rain, snowfall and snow depth: Detroit Metro Airport (USW00094847), 10 mi SW of the city center, 631 ft . NOAA normals and daily records, 1991-2020.
  • Humidity and wind by hour: Detroit City Airport (USW00014822), 10 mi NE of the city center, 626 ft . NOAA normals and daily records, 1991-2020.
  • Cloud cover: Flint Bishop Intl Airport (USW00014826), 53 mi NNW of the city center, 770 ft (179 ft higher than the city). NOAA normals and daily records, 1991-2020.
  • Daily humidity and wind: Detroit Metro Wayne County Airport (725370-94847), 10 mi SW of the city center, 630 ft . Hourly observations, 1991-2020.