September weather forecastGuyaz, ID
September
Weather in September
The first month of the autumn, September, is also an agreeable month in Guyaz, Idaho, with an average temperature ranging between min 46.4°F (8°C) and max 71.2°F (21.8°C).Temperature
As August shifts into September, a slight alteration in temperatures is observed, with average highs reducing from a warm 81.1°F (27.3°C) to an agreeable 71.2°F (21.8°C). A notable decrease from the day's highest temperature marks September, culminating in an average low of 46.4°F (8°C).Humidity
In September, the average relative humidity in Guyaz is 45%.Rainfall
In September, the rain falls for 9.3 days. Throughout September, 1.18" (30mm) of precipitation is accumulated. Throughout the year, in Guyaz, there are 101.4 rainfall days, and 12.72" (323mm) of precipitation is accumulated.Snowfall
January through May, September through December are months with snowfall. September is the first month it typically snows. Throughout September, in the average 0.4 snowfall days, it receives 0.2" (5mm) of snow. In Guyaz, Idaho, during the entire year, snow falls for 85.8 days and aggregates up to 40.94" (1040mm) of snow.Daylight
The average length of the day in September is 12h and 29min.On the first day of September in Guyaz, sunrise is at 6:51 am and sunset at 8:01 pm. On the last day of the month, sunrise is at 7:23 am and sunset at 7:08 pm MDT.
Sunshine
In Guyaz, the average sunshine in September is 10h.UV index
In September, the average daily maximum UV index is 3. A UV Index of 3 to 5 symbolizes a medium vulnerability from unsafe exposure to UV radiation for the average person.Note: The daily maximum UV index of 3 in September interprets into the following advice:
Take necessary precautions - Suggestions to elude sunburn are provided. The Sun's most intense and consequently most harmful UV radiation during midday hours should be decreased by minimizing exposure and seeking shade. Employ a wide-brim hat for potent defense against up to 50% of UV rays. Heads up! The UV radiation from the Sun can almost be doubled by snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Guyaz, ID
- Average high temperature in September: 71.2°F
The warmest month (with the highest average high temperature) is July (82.4°F).
The month with the lowest average high temperature is December (27°F).
- Average low temperature in September: 46.4°F
The month with the highest average low temperature is July (52.7°F).
The coldest month (with the lowest average low temperature) is January (13.1°F).
Average pressure in September
Guyaz, ID
- Average pressure in September: 29.98"Hg
The month with the highest atmospheric pressure is January (30.29"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in September
Guyaz, ID
- Average wind speed in September: 6.9mph
The windiest month (with the highest average wind speed) is June (7.8mph).
The calmest month (with the lowest average wind speed) is January (5.5mph).
Average humidity in September
Guyaz, ID
- Average humidity in September: 45%
The month with the highest relative humidity is January (91%).
The month with the lowest relative humidity is August (39%).
Average rainfall in September
Guyaz, ID
- Average rainfall in September: 1.18"
The wettest month (with the highest rainfall) is May (1.54").
The driest month (with the least rainfall) is July (0.55").
Average rainfall days in September
Guyaz, ID
- Average rainfall days in September: 9.3 days
The month with the highest number of rainy days is May (13.5 days).
The month with the least rainy days is January (3 days).
Average snowfall in September
Guyaz, ID
- Average snowfall in September: 0.2"
The month with the highest snowfall is January (8.11").
The months with the least snowfall are June, July and August (0").
Average snowfall days in September
Guyaz, ID
- Average snowfall days in September: 0.4 days
The month with the highest number of snowfall days is December (16.9 days).
The months with the least snowfall days are July and August (0 days).
Average daylight in September /
Average sunshine in September
Guyaz, ID
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 24min).
The month with the shortest days is December (Average daylight: 9h and 0min).
- Average sunshine in September: 10h and 0min
The month with the most sunshine is July (Average sunshine: 11h and 54min).
The month with the least sunshine is January (Average sunshine: 4h and 24min).
Average sunshine days in September
Guyaz, ID
- Average sunshine days in September: 17.8 days
The month with the most sunshine days is July (19.8 days).
The month with the least sunshine days is February (10.3 days).
Average UV index in September
Guyaz, ID
- Average UV index in September: 3
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February and December (UV index 1).
Average cloud cover in September
Guyaz, ID
- Average cloud cover in September: 16
The month with the most cloud cover is February (Cloud cover 56).
The months with the least cloud cover are July and August (Cloud cover 12).
Average visibility in September
Guyaz, ID
- Average visibility in September: 6mi
The months with the highest visibility are April, May, June, July, August, September, October and November (6mi).
The months with the lowest visibility are January, February and December (4mi).





