Climate and monthly weather forecastAlton, MO
Climate and monthly weather forecast
Weather in January
January, like December, is a frosty winter month in Alton, Missouri, with temperature in the range of an average low of 28.4°F (-2°C) and an average high of 43.3°F (6.3°C). January is the coldest month, with the temperature often reaching an average high of 43.3°F (6.3°C) and an average low of 28.4°F (-2°C). Weather in January »Weather in February
The last month of the winter, February, is also a frosty month in Alton, Missouri, with temperature in the range of an average high of 47.5°F (8.6°C) and an average low of 31.8°F (-0.1°C). February denotes a minimal variation in the average high-temperature to a still chilly 47.5°F (8.6°C) from January's 43.3°F (6.3°C). Weather in February »Weather in March
March, the first month of the spring in Alton, is a mild month, with temperature in the range of an average high of 57.7°F (14.3°C) and an average low of 40.1°F (4.5°C). March's arrival brings a temperature shift, moving from a chilly 47.5°F (8.6°C) in February to a refreshing 57.7°F (14.3°C). Weather in March »Weather in April
April is a refreshing spring month in Alton, Missouri, with temperature in the range of an average high of 67.8°F (19.9°C) and an average low of 48.9°F (9.4°C). An escalation in the average high-temperature is seen with the onset of April, moving from a refreshing 57.7°F (14.3°C) in March to a comfortable 67.8°F (19.9°C). Weather in April »Weather in May
May, the last month of the spring in Alton, is a warm month, with an average temperature fluctuating between 57.6°F (14.2°C) and 77.2°F (25.1°C). With the onset of May, Alton's average high-temperature experiences a rise, moving from April's refreshing 67.8°F (19.9°C) to a moderately hot 77.2°F (25.1°C). Weather in May »Weather in June
June, the first month of the summer in Alton, is a hot month, with temperature in the range of an average high of 86.9°F (30.5°C) and an average low of 66°F (18.9°C). In Alton, the average high-temperature in June increases from a warm 77.2°F (25.1°C) in May to a tropical 86.9°F (30.5°C). Weather in June »Weather in July
July, the same as June, in Alton, Missouri, is another hot summer month, with temperature in the range of an average low of 68.5°F (20.3°C) and an average high of 89.4°F (31.9°C). July, on average, is the warmest month, registering a high temperature of 89.4°F (31.9°C) and a low of 68.5°F (20.3°C). July's mean heat index is computed to be a blistering 107.6°F (42°C). Weather in July »Weather in August
August, the last month of the summer in Alton, is another tropical month, with an average temperature ranging between min 67.5°F (19.7°C) and max 88.3°F (31.3°C). August's arrival brings an average high-temperature of a still tropical 88.3°F (31.3°C), slightly deviating from July's 89.4°F (31.9°C). Weather in August »Weather in September
September, the first month of the autumn in Alton, is also a moderately hot month, with temperature in the range of an average high of 81.9°F (27.7°C) and an average low of 60.8°F (16°C). September witnesses a gentle descent in average high-temperature, descending from August's tropical 88.3°F (31.3°C) to a moderately hot 81.9°F (27.7°C). Weather in September »Weather in October
October, the same as September, in Alton, Missouri, is another pleasant autumn month, with an average temperature ranging between max 69.1°F (20.6°C) and min 49.8°F (9.9°C). The beginning of October marks a decrease in the average high-temperature, transitioning from a warm 81.9°F (27.7°C) in September to an agreeable 69.1°F (20.6°C). Weather in October »Weather in November
The last month of the autumn, November, is another refreshing month in Alton, Missouri, with an average temperature ranging between min 39.7°F (4.3°C) and max 56.1°F (13.4°C). With the beginning of November, the average high-temperature shows a decrease, transitioning from an agreeable 69.1°F (20.6°C) in October to a mild 56.1°F (13.4°C). Weather in November »Weather in December
The first month of the winter, December, is also a frosty month in Alton, Missouri, with an average temperature varying between 46.8°F (8.2°C) and 32.5°F (0.3°C). The start of December signals a decrease in the average high-temperature, transitioning from a moderate 56.1°F (13.4°C) in November to a frosty 46.8°F (8.2°C). Weather in December »Updated: Jul 5, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
January, known for its average high temperature of 43.3°F (6.3°C) and an average low temperature of 28.4°F (-2°C), is the coldest month.
Throughout the year, there are 148 rainfall days, and 35.39" (899mm) of precipitation is accumulated.
January through April, November and December are months with snowfall.
In Alton, during the entire year, snow falls for 8.9 days and aggregates up to 4.57" (116mm) of snow.
The months with the lowest UV index are January and December, with an average maximum UV index of 2.
The month with the most snowfall is February, when snow falls for 2.8 days and typically aggregates up to 1.26" (32mm) of snow.
February has the least sunshine of the year, with an average of 4.8h of sunshine.
March and May, with an average relative humidity of 79%, are most humid months.
On Sunday, March 10. 2024, at 2:00 am, Daylight Saving Time starts, and the time zone changes from CST to CDT. Daylight Saving Time ends Sunday, November 3. 2024, at 2:00 am, and the time zone reverts from CDT to CST.
The month with the most rainfall is May, when the rain falls for 16.5 days and typically aggregates up to 4.25" (108mm) of precipitation.
May through October are months without snowfall.
The month with the longest days is June, with an average of 14h and 36min of daylight.
June has the most sunshine of the year, with an average of 10.4h of sunshine.
The month with the highest UV index in Alton is June, with an average maximum UV index of 7.
The warmest month in Alton is July, with an average high-temperature of 89.4°F (31.9°C) and an average low-temperature of 68.5°F (20.3°C).
The month with the least rainfall is September, when the rain falls for 12 days and typically collects 1.57" (40mm) of precipitation.
October is the least humid month, with an average relative humidity of 72%.
With an average of 9h and 42min of daylight, December has the shortest days of the year.
Average temperature
Alton, MO
The warmest month (with the highest average high temperature) is July (89.4°F).
The month with the lowest average high temperature is January (43.3°F).
The month with the highest average low temperature is July (68.5°F).
The coldest month (with the lowest average low temperature) is January (28.4°F).
Average pressure
Alton, MO
- Average pressure in January:
30.16"Hg - Average pressure in February:
30.12"Hg - Average pressure in March:
30.07"Hg - Average pressure in April:
29.95"Hg - Average pressure in May:
29.96"Hg - Average pressure in June:
29.93"Hg
- Average pressure in July:
29.97"Hg - Average pressure in August:
29.97"Hg - Average pressure in September:
30.02"Hg - Average pressure in October:
30.04"Hg - Average pressure in November:
30.13"Hg - Average pressure in December:
30.14"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed
Alton, MO
- Average wind speed in January:
8.1mph - Average wind speed in February:
8.1mph - Average wind speed in March:
8.1mph - Average wind speed in April:
8.1mph - Average wind speed in May:
6.9mph - Average wind speed in June:
5.9mph
- Average wind speed in July:
5.3mph - Average wind speed in August:
5.3mph - Average wind speed in September:
5.7mph - Average wind speed in October:
6.9mph - Average wind speed in November:
7.5mph - Average wind speed in December:
7.6mph
The windiest months (with the highest average wind speed) are January, February, March and April (8.1mph).
The calmest months (with the lowest average wind speed) are July and August (5.3mph).
Average humidity
Alton, MO
The months with the highest relative humidity are March and May (79%).
The month with the lowest relative humidity is October (72%).
Average rainfall
Alton, MO
- Average rainfall in January:
2.56" - Average rainfall in February:
2.6" - Average rainfall in March:
3.66" - Average rainfall in April:
4.13" - Average rainfall in May:
4.25" - Average rainfall in June:
2.68"
- Average rainfall in July:
3.15" - Average rainfall in August:
2.8" - Average rainfall in September:
1.57" - Average rainfall in October:
2.91" - Average rainfall in November:
2.52" - Average rainfall in December:
2.56"
The wettest month (with the highest rainfall) is May (4.25").
The driest month (with the least rainfall) is September (1.57").
Average rainfall days
Alton, MO
- Average rainfall days in January:
8.6 days - Average rainfall days in February:
9 days - Average rainfall days in March:
14.1 days - Average rainfall days in April:
13.5 days - Average rainfall days in May:
16.5 days - Average rainfall days in June:
14.3 days
- Average rainfall days in July:
15.1 days - Average rainfall days in August:
15.8 days - Average rainfall days in September:
12 days - Average rainfall days in October:
10.8 days - Average rainfall days in November:
9 days - Average rainfall days in December:
9.3 days
The month with the highest number of rainy days is May (16.5 days).
The month with the least rainy days is January (8.6 days).
Average snowfall
Alton, MO
The month with the highest snowfall is February (1.26").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days
Alton, MO
- Average snowfall days in January:
2.5 days - Average snowfall days in February:
2.8 days - Average snowfall days in March:
1.1 days - Average snowfall days in April:
0.2 days - Average snowfall days in May:
0 days - Average snowfall days in June:
0 days
- Average snowfall days in July:
0 days - Average snowfall days in August:
0 days - Average snowfall days in September:
0 days - Average snowfall days in October:
0 days - Average snowfall days in November:
0.7 days - Average snowfall days in December:
1.6 days
The month with the highest number of snowfall days is February (2.8 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight / Average sunshine
Alton, MO
- Average daylight in January:
10h and 0min - Average daylight in February:
10h and 54min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 12min - Average daylight in May:
14h and 6min - Average daylight in June:
14h and 36min
- Average daylight in July:
14h and 24min - Average daylight in August:
13h and 30min - Average daylight in September:
12h and 24min - Average daylight in October:
11h and 12min - Average daylight in November:
10h and 12min - Average daylight in December:
9h and 42min
The month with the longest days is June (Average daylight: 14h and 36min).
The month with the shortest days is December (Average daylight: 9h and 42min).
- Average sunshine in January:
5h and 6min - Average sunshine in February:
4h and 48min - Average sunshine in March:
6h and 18min - Average sunshine in April:
8h and 12min - Average sunshine in May:
8h and 42min - Average sunshine in June:
10h and 24min
- Average sunshine in July:
10h and 12min - Average sunshine in August:
10h and 6min - Average sunshine in September:
9h and 24min - Average sunshine in October:
5h and 54min - Average sunshine in November:
5h and 36min - Average sunshine in December:
5h and 0min
The month with the most sunshine is June (Average sunshine: 10h and 24min).
The month with the least sunshine is February (Average sunshine: 4h and 48min).
Average sunshine days
Alton, MO
- Average sunshine days in January:
19.3 days - Average sunshine days in February:
15.6 days - Average sunshine days in March:
14.4 days - Average sunshine days in April:
14.5 days - Average sunshine days in May:
12.3 days - Average sunshine days in June:
13.3 days
- Average sunshine days in July:
13.1 days - Average sunshine days in August:
12.7 days - Average sunshine days in September:
16.5 days - Average sunshine days in October:
18.7 days - Average sunshine days in November:
19.3 days - Average sunshine days in December:
19.6 days
The month with the most sunshine days is December (19.6 days).
The month with the least sunshine days is May (12.3 days).
Average UV index
Alton, MO
The month with the highest UV index is June (UV index 7).
The months with the lowest UV index are January and December (UV index 2).
Average cloud cover
Alton, MO
The month with the most cloud cover is March (Cloud cover 49).
The month with the least cloud cover is June (Cloud cover 29).
Average visibility
Alton, MO
The months with the highest visibility are January, February, March, April, June, August, September, October, November and December (6mi).
The months with the lowest visibility are May and July (5mi).
