Milwaukee in September

In September, Milwaukee averages 23°C (73°F) during the day and 16°C (60°F) at night, with around 10 days of rain (98 mm total).

Shoulder

Conditions are comfortable for sightseeing without being sweltering. Plan for unsettled weather and bring rain gear.

It's peak hurricane season in Milwaukee during September. Travel is possible but expect storm risk, possible flight disruption, and generally lower travel insurance coverage.

23°C
Avg high
16°C
Avg low
10
Rain days
98 mm
Rainfall

How September compares to the rest of the year in Milwaukee

4th
warmest month of the 12
7th
wettest month of the 12
10%
of yearly rainfall falls in September
12 h 32 min
daylight on the 15th

September is in the middle of the year for warmth in Milwaukee (4th of 12) and moderately rainy compared to the rest of the year (7th of 12). Daytime temperature runs 9°C above the annual average (13°C). September runs 3°C cooler than August (26°C) and cools 7°C in October (15°C).

September sunrise & sunset in Milwaukee

🌅
Sunrise (15th)
6:31 AM
🌇
Sunset (15th)
7:02 PM
Day length
12 h 32 min

Times shown for Milwaukee local time (America/Chicago), calculated for the 15th of September. They shift by a few minutes day to day across the month.

Photography light in Milwaukee — September

Golden-hour and blue-hour windows for the 15th of September, in Milwaukee's local time. Use these for soft warm light (golden) or cool architectural twilight (blue).

🌅 Blue hour (AM)
5:31 AM – 6:11 AM
🌄 Golden hour (AM)
6:11 AM – 7:11 AM
🌇 Golden hour (PM)
6:22 PM – 7:22 PM
🌆 Blue hour (PM)
7:22 PM – 8:02 PM
Milky Way galactic core
Fair
Core only briefly above the horizon — a marginal month even from dark sites near Milwaukee.

📅 When to book — Milwaukee in September

Travel writers usually only tell you when to go. Here's when to book flights and lodging for the best mix of price and availability, based on September's tier (Shoulder) and Milwaukee's popularity.

✈ Flights — lead time
6-10 weeks
Sweet spot for value. Major fare-sales (US: Black Friday, EU: post-Easter) hit hardest in shoulder months for shoulder travel. ⚠ Peak hazard season — book flexible-change tickets and travel insurance with weather-disruption coverage.
🏨 Lodging — lead time
4-8 weeks
Lots of selection. Look for shoulder-season packages — many hotels add value (free breakfast, spa credit) to fill rooms.

Crowds & pricing — September in Milwaukee

Shoulder

Milwaukee is in a shoulder season month — fewer crowds, slightly lower prices, and a calmer atmosphere than peak weeks. Most major sights stay open with normal hours, though a handful of seasonal restaurants or boat trips may run reduced schedules. Many regulars consider these months the best time to visit because you trade a small amount of weather reliability for a much more pleasant on-the-ground experience.

Why this tier: excellent tourism weather peak hazard season (1 active)

Sun & mosquito risk — September in Milwaukee

☀️ UV Index (noon, 15th)
9
Very high
Limit sun exposure between 11 AM and 3 PM; SPF 30-50, reapply every 90 minutes outdoors.
🦟 Mosquito risk
●●●○○
Moderate
Active mosquito season. DEET 25-30% repellent recommended, especially at dawn/dusk.

UV is a clear-sky sea-level estimate — clouds, altitude, and reflective surfaces (snow, water) shift it ±30%. Mosquito risk is climate-derived only; for current disease advisories (dengue, malaria, zika) check the CDC or WHO travel pages before your trip.

Milwaukee in other months

MonthAvg highAvg lowRainfallRain daysSnow days
January -1°C / 30°F -8°C / 18°F 47 mm 8
February 0°C / 32°F -8°C / 17°F 49 mm 8
March 5°C / 42°F -2°C / 28°F 66 mm 10
April 11°C / 51°F 3°C / 37°F 102 mm 13
May 17°C / 63°F 9°C / 48°F 104 mm 12
June 23°C / 74°F 15°C / 59°F 113 mm 12
July 26°C / 79°F 18°C / 65°F 83 mm 10
August 26°C / 79°F 18°C / 65°F 78 mm 10
September 23°C / 73°F 16°C / 60°F 98 mm 10
October 15°C / 60°F 9°C / 48°F 108 mm 10
November 8°C / 46°F 1°C / 34°F 52 mm 7
December 3°C / 37°F -3°C / 26°F 57 mm 9

Other cities with similar September weather

🌍 See the full ranked list of climate twins for Milwaukee in September →

Frequently asked questions

How hot is Milwaukee in September?

In September, Milwaukee averages a high of 23°C (73°F) and a low of 16°C (60°F) — generally mild and pleasant.

Does it rain a lot in Milwaukee in September?

September can be fairly wet in Milwaukee, with about 10 rainy days on average.

Is September a good time to visit Milwaukee?

September is mild and pleasant. It suits travelers who are comfortable with mild and pleasant weather; check the month-by-month ranking to compare it against the rest of the year.

What should I pack for Milwaukee in September?

Pack light layers for warm days and cooler evenings, plus a compact umbrella or rain jacket. See the full September packing list for Milwaukee for a complete, climate-based checklist.

Open Milwaukee on the interactive map

Check the live 10-day forecast and sunrise/sunset.