Maui in September: My Honest Take + Real Climate Data

Here’s how Maui’s five main activities stack up in September, scored against 5 years of historical weather at the spots where each one actually happens.

If you can pick your week, book this one

September 17–23

In 5 of the last 5 years, 5+ of those 7 days hit the bar — the most reliable week of the month. Averaged 6.8/7 good days.

How beach days trend across the year

Share of days that clear the beach bar, by month — September highlighted.

Activity by activity

🏖️ Beach Day · September · South Maui (leeward)

Go for it — the odds are strongly in your favor.

GO

87% of days hit the bar — 131 of 150 days across 5 years.

Avg high
84°F
Avg daily rain
0.04 in
Avg max wind
9 mph

My bar for a beach day: ≤0.08 in rain · ≥75°F high · ≤16 mph wind

🥾 Hiking · September · Upcountry (~700m)

Go for it — the odds are strongly in your favor.

GO

96% of days hit the bar — 144 of 150 days across 5 years.

Avg high
79°F
Avg daily rain
0.04 in
Avg max wind
12 mph

My bar for a hiking: ≤0.20 in rain · 64°F–86°F high

If you can pick your week, book this one

September 23–29

In 5 of the last 5 years, 5+ of those 7 days hit the bar — the most reliable week of the month. Averaged 7/7 good days.

🤿 Snorkeling · September · South Maui (leeward)

Go for it — the odds are strongly in your favor.

GO

89% of days hit the bar — 134 of 150 days across 5 years.

Avg high
84°F
Avg daily rain
0.04 in
Avg max wind
9 mph

My bar for a snorkeling: ≤0.12 in rain · ≥75°F high · ≤12 mph wind

If you can pick your week, book this one

September 17–23

In 5 of the last 5 years, 5+ of those 7 days hit the bar — the most reliable week of the month. Averaged 6.8/7 good days.

🚁 Helicopter Tour · September · Kahului

I’d skip it — most days this month miss the mark.

SKIP

13% of days hit the bar — 19 of 150 days across 5 years.

Avg high
85°F
Avg daily rain
0.01 in
Avg max wind
19 mph

My bar for a helicopter tour: ≤0.04 in rain · ≤16 mph wind

⛵ Boat Tour · September · Māʻalaea Bay

Go for it — the odds are strongly in your favor.

GO

100% of days hit the bar — 150 of 150 days across 5 years.

Avg high
85°F
Avg daily rain
0.00 in
Avg max wind
10 mph

My bar for a boat tour: ≤0.20 in rain · ≤19 mph wind

If you can pick your week, book this one

September 17–23

In 5 of the last 5 years, 5+ of those 7 days hit the bar — the most reliable week of the month. Averaged 7/7 good days.

Not sure this is your month? Compare all 12 months·The best time to visit

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