Mackinac Island weather in August

In August, Mackinac Island sees average daytime highs of 73°F and overnight lows near 62°F, with 3.4 in of rain across 10 wet days and about 13.9 hours of daylight. It is the 2nd-warmest and 3rd-wettest month of the year here.

Highs ease over the month, from about 75°F in the first days to 71°F by the end. The sky is clear or mostly clear about 39% of the time in August, and the air most often feels humid.

Daylight stretches from about 14 h 36 min at the start of August to 13 h 12 min by month's end. Set against the rest of the year, August is Mackinac Island's 2nd-clearest and 10th-windiest month. For the whole year in context, see Mackinac Island's year-round climate.

Daytime high
73°
2nd warmest
Overnight low
62°
11th coldest
Rainfall
3.4 in
10 wet days
Daylight
14 hours
5:44 AM – 7:41 PM
Cloud cover
52%
2nd clearest
Wind
9 mph
10th windiest
Solar energy
5.49 kWh/m²
Travel score
6.9
out of 10

Mackinac Island is city located on Mackinac Island in Michigan.

Founded
1671

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in August

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 75°F in the first days to 71°F by the end.

A typical August day in Mackinac Island reaches about 73°F in the afternoon and slips back to 62°F overnight — a 11°F spread between the day's warmth and the night's chill. On most days the high lands between 66°F and 79°F. Set against its neighbours, August runs on par with July and about 7°F warmer than September.

50°60°70°80°151015202531
Avg high (°F)Avg low (°F)
17563
27563
37563
47463
57463
67463
77463
87463
97463
107462
117462
127462
137462
147362
157362
167362
177362
187362
197362
207361
217361
227361
237261
247261
257261
267260
277260
287260
297160
307160
317160

How August really feels in Mackinac Island

Once humidity and wind are folded in, August averages 0 days that feel above 90°F and 0 that feel at or below 32°F — the comfort signal a plain temperature reading hides.

Days feeling ≥ 90°F
0
heat index over the day's high
Days feeling ≤ 32°F
0
wind chill below the day's low

August sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Mackinac Island weather by month

How August compares with the rest of the year at a glance. August is the 2nd-warmest and 3rd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan24° / 14°1.99.910.98.90.0
Feb24° / 13°1.67.47.310.10.0
Mar33° / 21°2.08.46.111.60.0
Apr44° / 32°2.99.73.213.30.9
May56° / 43°2.910.20.314.73.7
Jun68° / 55°3.010015.56.3
Jul74° / 62°3.310.9015.26.9
Aug73° / 62°3.410013.96.9
Sep66° / 55°3.511.4012.35.9
Oct54° / 44°3.713.50.210.73.0
Nov42° / 34°2.611.65.79.30.5
Dec32° / 24°2.311.311.38.50.0

Cloud cover in August

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 39% of the time in August.

Beyond those clear spells, partly cloudy skies cover about 18% of August, with mostly cloudy or overcast conditions the remaining 43%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
16040
26139
36139
46139
56139
66139
76139
86040
96040
106040
116040
125941
135842
145842
155743
165644
175644
185545
195446
205446
215446
225446
235347
245446
255446
265545
275545
285644
295644
305644
315743

Chance of precipitation in August

Any precipitation

Mackinac Island gets around 3.4 in of rain over 10 wet days in August. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 33% and peaks near 36% on the wettest days.

0%10%20%30%40%50%151015202531
Rain chance (%)
136
235
335
435
534
634
733
833
933
1033
1133
1233
1333
1433
1532
1632
1732
1832
1932
2032
2132
2232
2332
2432
2532
2632
2732
2832
2932
3033
3133

Humidity in August

DryComfortableHumidMuggyOppressiveMiserable

Most of August feels humid — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, August lands in the humid band about 31% of days. Sticky, muggy-or-worse air turns up on roughly 16% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1162834193
2162833193
3172833193
4172833193
5182833183
6182832183
7192832173
8202832173
9212832163
10222832153
11222832153
12232832143
13242832142
14242832142
15242833142
16252832132
17252832141
18252832141
19252832141
20252931141
21262931140
22262930140
23263030140
24263029140
25273129140
26273128130
27283128130
28293127130
29303126130
30313126120
31323125120

Wind in August

Winds average 9 mph in August.

Across August, daily wind ranges from about 9 mph on the calmest days to 9 mph at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (mph)Feels
19light breeze
29light breeze
39light breeze
49light breeze
59light breeze
69light breeze
79light breeze
89light breeze
99light breeze
109light breeze
119light breeze
129light breeze
139light breeze
149light breeze
159light breeze
169light breeze
179light breeze
189light breeze
199light breeze
209light breeze
219light breeze
229light breeze
239light breeze
249light breeze
259light breeze
269light breeze
279light breeze
289light breeze
299light breeze
309light breeze
319light breeze

Sunrise & sunset in August

DaylightNight

Daylight runs from about 14 h 36 min at the start of August to 13 h 12 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 84 minutes over August. Sunrise moves from 5:25 AM to 6:03 AM, and sunset from 8:04 PM to 7:14 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
114.65:258:04
214.65:268:03
314.65:288:01
414.55:298:00
514.55:307:58
614.45:317:57
714.45:327:56
814.35:347:54
914.35:357:53
1014.25:367:51
1114.25:377:50
1214.25:397:48
1314.15:407:46
1414.15:417:45
1514.05:427:43
1614.05:447:41
1713.95:457:40
1813.95:467:38
1913.85:477:36
2013.85:497:35
2113.75:507:33
2213.75:517:31
2313.65:537:29
2413.65:547:27
2513.55:557:26
2613.55:567:24
2713.45:587:22
2813.45:597:20
2913.36:007:18
3013.26:027:16
3113.26:037:14

Solar energy in August

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in August, about 5.49 kWh/m².

For context, solar energy here swings from a low near 1.15 kWh/m² to a high of 6.61 kWh/m² in June across the year — August's 5.49 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
16.1Intense
26.0Intense
36.0Intense
46.0Bright
55.9Bright
65.9Bright
75.9Bright
85.8Bright
95.8Bright
105.8Bright
115.7Bright
125.7Bright
135.7Bright
145.6Bright
155.6Bright
165.5Bright
175.5Bright
185.4Bright
195.4Bright
205.3Bright
215.3Bright
225.2Bright
235.2Bright
245.2Bright
255.1Bright
265.1Bright
275.0Bright
285.0Bright
294.9Bright
304.9Bright
314.9Bright
Planning a trip in August

Is August a good time to visit Mackinac Island?

Our two travel scores rate August for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

6.9
Sightseeing
1st-best month of the year
5.3
Beach & pool
2nd-best month of the year

August is a reasonable time to visit Mackinac Island for sightseeing.

What to pack for Mackinac Island in August

From August's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In August, Mackinac Island sees daytime highs around 73°F and nights near 62°F. Worth packing: light clothes, rain gear and sun protection. About 10 days see rain.

light clothesrain gearsun protection

Sea temperature near Mackinac Island in August

The nearest coast averages about 66°F in August — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea offshore is warmest in August at about 66°F and coldest in February near 34°F.

The water stays below 68°F all year — cool enough that most swimmers want a wetsuit.

30°40°50°60°70°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshing
Sea temperature (°F)Comfort
Jan35Bracing
Feb34Bracing
Mar34Bracing
Apr36Bracing
May41Bracing
Jun52Bracing
Jul62Cool
Aug66Cool
Sep61Cool
Oct53Bracing
Nov44Bracing
Dec38Bracing

UV index in Mackinac Island in August

LowModerateHighVery highExtreme

Clear-sky midday UV in August peaks around 7 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Mackinac Island peaks around June 19 at about 8 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near January 1 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 7 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJun 19UV 8Jan 1UV 1
UV index (midday)Level
Jan1Low
Feb2Low
Mar3Moderate
Apr5Moderate
May7High
Jun8Very high
Jul8Very high
Aug7High
Sep5Moderate
Oct3Moderate
Nov2Low
Dec1Low
Location & terrain

Where is Mackinac Island?

Mackinac Island sits at 45.8°N, 84.6°W, 0 ft above sea level, in United States. The nearest listed city is Sault Ste. Marie, 47 mi away.

Topography around Mackinac Island

How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Mackinac Island.

Within 2 miles, the terrain around Mackinac Island has only modest variations in elevation — a maximum elevation change of 351 ft around an average of 614 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 351 ft; within 50 miles, significant variations in elevation — a maximum elevation change of 1,037 ft.

The land around Mackinac Island is covered by water (72%) and trees (24%) within 2 miles, water (75%) and trees (22%) within 10 miles, and trees (48%) and water (44%) within 50 miles.

2 miles
351 ft
10 miles
351 ft
50 miles
1,037 ft
treesgrasslandcroplandartificial surfaceswater
August weather nearby: Sault Ste. Marie 47 mi · Sault Ste. Marie 48 mi · Traverse City 89 mi · Marquette 141 mi · Midland 155 mi · Mount Pleasant 156 mi · Bay City 160 mi · Saginaw Township North 168 mi

United States travel facts

Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 100% of US
price level, 2025
GDP per capita
$90,027
2025
Happiness
6.8 / 10
World Happiness, 2025
Safe drinking water
98%
of population, 2024
Homicide rate
5.8
per 100k, 2023
Road deaths
12.7
per 100k/yr, 2019
Income group
High
World Bank
Religion
Protestant 47%unaffiliated 23%Roman Catholic 21%Jewish 2%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Mackinac Island (45.8492°, -84.6189°, elevation 0 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).