Monthly outlook for Alton, MI: average high 72.1°, average low 55.9°. That is 0.8° below the climate normal for August. Precipitation is expected on 4 days (about 1.1 inches), against a normal of 5 days and 1.5 inches. The warmest day looks like 17 August (79.3°), the coolest 15 August (49.4°).
72.1°/55.9°
Average high / low
−0.8°
Below normal
4 / 5
Wet days / normal
1.1 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
9 August – 18 August
74°
74°
-0°
19 August – 28 August
69.1°
72.8°
-2.1°
29 August – 7 September
at normal
70.9°
—
August records over 66 years
90.9°7 August 2001All-time high
45.5°29 August 2025All-time low
Climate normals and records are computed from the nearest reference point — Escanaba (14 mi).
Mon, 1077° / 58°0.03
77 °
Alton, Monday, 10 August
Light rain. High 77°, low 58°.
Pressure29.91 inHg
Wind0.4 mph S
Humidity53%
Visibility6.2 mi
Dew point56°
Tue, 1174° / 60°0.13
74 °
Alton, Tuesday, 11 August
Light rain. High 74°, low 60°.
Pressure29.88 inHg
Wind5.1 mph S
Humidity78%
Visibility6.2 mi
Dew point60°
Wed, 1269° / 53°0.04
69 °
Alton, Wednesday, 12 August
Light rain. High 69°, low 53°.
Pressure29.83 inHg
Wind10.9 mph N
Humidity55%
Visibility6.2 mi
Dew point55°
Thu, 1370° / 49°0
70 °
Alton, Thursday, 13 August
Overcast. High 70°, low 49°.
Pressure29.97 inHg
Wind7.3 mph NW
Humidity51%
Visibility—
Dew point47°
Fri, 1473° / 53°0
73 °
Alton, Friday, 14 August
Clear. High 73°, low 53°.
Pressure30.12 inHg
Wind14.3 mph N
Humidity40%
Visibility—
Dew point45°
Sat, 1570° / 49°0
70 °
Alton, Saturday, 15 August
Overcast. High 70°, low 49°.
Pressure30.30 inHg
Wind5.6 mph S
Humidity46%
Visibility—
Dew point46°
Sun, 1677° / 58°0
77 °
Alton, Sunday, 16 August
Partly cloudy. High 77°, low 58°.
Pressure30.06 inHg
Wind12.8 mph S
Humidity48%
Visibility—
Dew point54°
Mon, 1779° / 63°0
79 °
Alton, Monday, 17 August
Partly cloudy. High 79°, low 63°.
Pressure29.97 inHg
Wind6.9 mph SW
Humidity47%
Visibility—
Dew point55°
Tue, 1876° / 61°0.56
76 °
Alton, Tuesday, 18 August
Rain. High 76°, low 61°.
Pressure29.85 inHg
Wind11.1 mph S
Humidity93%
Visibility—
Dew point66°
Wed, 1964° / 58°0.03
64 °
Alton, Wednesday, 19 August
Light rain. High 64°, low 58°.
Pressure29.80 inHg
Wind17.9 mph N
Humidity87%
Visibility—
Dew point56°
Thu, 2070° / 53°0
70 °
Alton, Thursday, 20 August
Overcast. High 70°, low 53°.
Pressure30.03 inHg
Wind14.4 mph N
Humidity41%
Visibility—
Dew point43°
Fri, 2172° / 51°0
72 °
Alton, Friday, 21 August
Overcast. High 72°, low 51°.
Pressure30.12 inHg
Wind8.4 mph S
Humidity44%
Visibility—
Dew point46°
Sat, 2268° / 57°0.25
68 °
Alton, Saturday, 22 August
Rain. High 68°, low 57°.
Pressure29.88 inHg
Wind14.8 mph S
Humidity78%
Visibility—
Dew point57°
Sun, 2370° / 58°0.03
70 °
Alton, Sunday, 23 August
Light rain. High 70°, low 58°.
Pressure29.74 inHg
Wind16.1 mph NW
Humidity62%
Visibility—
Dew point55°
Mon, 2471° / 54°0
71 °
Alton, Monday, 24 August
Overcast. High 71°, low 54°.
Pressure30.03 inHg
Wind5.6 mph NW
Humidity56%
Visibility—
Dew point52°
From day 17 onward the outlook is built from 60-year climate statistics
Tue, 2573° / 63°0.13
73 °
Alton, Tuesday, 25 August
Climate normal for this date — 60-year average.
Average high73°
Average low63°
Average precipitation0.13 in
Chance of precipitation33%
Record high84° (2013)
Record low47° (2017)
Wed, 2673° / 63°0.12
73 °
Alton, Wednesday, 26 August
Climate normal for this date — 60-year average.
Average high73°
Average low63°
Average precipitation0.12 in
Chance of precipitation40%
Record high86° (2013)
Record low49° (2025)
Thu, 2773° / 63°0.19
73 °
Alton, Thursday, 27 August
Climate normal for this date — 60-year average.
Average high73°
Average low63°
Average precipitation0.19 in
Chance of precipitation40%
Record high85° (1983)
Record low48° (2025)
Fri, 2872° / 63°0.1
72 °
Alton, Friday, 28 August
Climate normal for this date — 60-year average.
Average high72°
Average low63°
Average precipitation0.1 in
Chance of precipitation30%
Record high86° (1991)
Record low48° (1986)
Sat, 2972° / 62°0.1
72 °
Alton, Saturday, 29 August
Climate normal for this date — 60-year average.
Average high72°
Average low62°
Average precipitation0.1 in
Chance of precipitation33%
Record high85° (2022)
Record low46° (2025)
Sun, 3072° / 62°0.15
72 °
Alton, Sunday, 30 August
Climate normal for this date — 60-year average.
Average high72°
Average low62°
Average precipitation0.15 in
Chance of precipitation33%
Record high91° (1991)
Record low49° (2023)
Mon, 3171° / 61°0.06
71 °
Alton, Monday, 31 August
Climate normal for this date — 60-year average.
Average high71°
Average low61°
Average precipitation0.06 in
Chance of precipitation30%
Record high81° (2012)
Record low51° (2017)
Tue, 0171° / 61°0.09
71 °
Alton, Tuesday, 1 September
Climate normal for this date — 60-year average.
Average high71°
Average low61°
Average precipitation0.09 in
Chance of precipitation28%
Record high84° (1990)
Record low50° (1974)
Wed, 0271° / 62°0.09
71 °
Alton, Wednesday, 2 September
Climate normal for this date — 60-year average.
Average high71°
Average low62°
Average precipitation0.09 in
Chance of precipitation33%
Record high82° (2011)
Record low49° (1976)
Thu, 0371° / 61°0.16
71 °
Alton, Thursday, 3 September
Climate normal for this date — 60-year average.
Average high71°
Average low61°
Average precipitation0.16 in
Chance of precipitation32%
Record high84° (2023)
Record low47° (1974)
Fri, 0471° / 61°0.08
71 °
Alton, Friday, 4 September
Climate normal for this date — 60-year average.
Average high71°
Average low61°
Average precipitation0.08 in
Chance of precipitation30%
Record high84° (2023)
Record low44° (2025)
Sat, 0570° / 60°0.13
70 °
Alton, Saturday, 5 September
Climate normal for this date — 60-year average.
Average high70°
Average low60°
Average precipitation0.13 in
Chance of precipitation38%
Record high82° (2007)
Record low45° (2025)
Sun, 0670° / 60°0.08
70 °
Alton, Sunday, 6 September
Climate normal for this date — 60-year average.
Average high70°
Average low60°
Average precipitation0.08 in
Chance of precipitation33%
Record high82° (1978)
Record low49° (1988)
Mon, 0770° / 59°0.14
70 °
Alton, Monday, 7 September
Climate normal for this date — 60-year average.
Average high70°
Average low59°
Average precipitation0.14 in
Chance of precipitation37%
Record high83° (1960)
Record low44° (2025)
About the monthly outlook
How accurate is a 30-day forecast?
The first 16 days come from weather models — reliable for the first 3–5 days and progressively less so after that. Days 17 through 30 for Alton, MI are built from the climate normal, the 60-year average, so they show typical weather for those dates rather than a specific forecast.
What does "above normal" mean?
We compare the forecast against the climate normal for those exact calendar days, computed from 60 years of observations. The deviation shows how much the coming month differs from a typical one.
Where do the 66-year records come from?
They are real temperature extremes recorded in Alton, MI since 1960: the highest and lowest reading for each calendar date, with the year it happened.
How often is it updated?
The forecast portion refreshes every hour; the climate portion is based on long-term data and stays stable.