Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
The arrival of September signals a subtle shift in temperature, down from a warm 74.8°F (23.8°C) in August to a pleasant 68.5°F (20.3°C). September nights show a substantial disparity from the daytime peak with an average low-temperature of 43.7°F (6.5°C).Humidity
In San Luis, the average relative humidity in September is 51%.Rainfall
In San Luis, in September, during 7.1 rainfall days, 0.59" (15mm) of precipitation is typically accumulated. Throughout the year, in San Luis, Colorado, there are 72.2 rainfall days, and 8.82" (224mm) of precipitation is accumulated.Snowfall
Months with snowfall in San Luis, Colorado, are January through June, September through December. 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 San Luis, during the entire year, snow falls for 57.6 days and aggregates up to 28.58" (726mm) of snow.Daylight
The average length of the day in September in San Luis is 12h and 25min.On the first day of September in San Luis, Colorado, sunrise is at 6:32 am and sunset at 7:29 pm. On the last day of the month, sunrise is at 6:56 am and sunset at 6:45 pm MDT.
Sunshine
The average sunshine in September is 11h.UV index
In September, the average daily maximum UV index in San Luis is 4. A UV Index reading of 3 to 5 represents a medium health hazard from exposure to the Sun's UV radiation for the ordinary person.Note: In September, an average UV index of 4 transforms into the following instructions:
Exercise care. People with light skin might get burns in fewer than 30 minutes. The solar radiation is most powerful near the mid-day, so the exposure to the direct Sun should be reduced accordingly. Loose clothes with a tight weave are optimal for safeguarding yourself against the Sun's rays. Remember! The Sun's UV radiation can be magnified almost twofold by the reflection of snow.
Frequently asked questions
What is the average September temperature in San Luis?
What is the average humidity in September in San Luis?
How much does it rain in San Luis in September?
When does it start snowing in San Luis?
What is the average length of the day in September in San Luis?
What time are sunrise and sunset in September in San Luis?
How long on average sun shines in September in San Luis?
How high is the UV index in September in San Luis?
Average temperature in September
San Luis, CO
- Average high temperature in September: 68.5°F
The warmest month (with the highest average high temperature) is July (76.6°F).
The month with the lowest average high temperature is January (30.6°F).
- Average low temperature in September: 43.7°F
The month with the highest average low temperature is July (50.2°F).
The coldest month (with the lowest average low temperature) is January (9.3°F).
Average pressure in September
San Luis, CO
- Average pressure in September: 30.03"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is April (29.89"Hg).
Average wind speed in September
San Luis, CO
- Average wind speed in September: 6.5mph
The windiest months (with the highest average wind speed) are April and May (8.9mph).
The calmest month (with the lowest average wind speed) is July (5.5mph).
Average humidity in September
San Luis, CO
- Average humidity in September: 51%
The month with the highest relative humidity is January (82%).
The month with the lowest relative humidity is June (38%).
Average rainfall in September
San Luis, CO
- Average rainfall in September: 0.59"
The wettest month (with the highest rainfall) is July (1.61").
The driest month (with the least rainfall) is November (0.43").
Average rainfall days in September
San Luis, CO
- Average rainfall days in September: 7.1 days
The month with the highest number of rainy days is July (13.9 days).
The month with the least rainy days is November (1.3 days).
Average snowfall in September
San Luis, CO
- Average snowfall in September: 0.2"
The month with the highest snowfall is March (5.55").
The months with the least snowfall are July and August (0").
Average snowfall days in September
San Luis, CO
- Average snowfall days in September: 0.4 days
The month with the highest number of snowfall days is February (10.1 days).
The months with the least snowfall days are July and August (0 days).
Average daylight in September /
Average sunshine in September
San Luis, CO
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 42min).
- Average sunshine in September: 11h and 0min
The month with the most sunshine is June (Average sunshine: 11h and 48min).
The month with the least sunshine is January (Average sunshine: 6h and 30min).
Average sunshine days in September
San Luis, CO
- Average sunshine days in September: 20.5 days
The month with the most sunshine days is October (24.1 days).
The month with the least sunshine days is July (13.3 days).
Average UV index in September
San Luis, CO
- Average UV index in September: 4
The months with the highest UV index are June, July and August (UV index 5).
The months with the lowest UV index are January, February, March, October, November and December (UV index 2).
Average cloud cover in September
San Luis, CO
- Average cloud cover in September: 15
The month with the most cloud cover is January (Cloud cover 31).
The months with the least cloud cover are June and October (Cloud cover 14).
Average visibility in September
San Luis, CO
- Average visibility in September: 6mi
The months with the highest visibility are March, April, May, June, July, August, September, October and November (6mi).
The month with the lowest visibility is January (4mi).
San Luis, Colorado, USA
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