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
Merna, Wyoming, records a mild change in average high-temperature during September, easing from a warm 75°F (23.9°C) in August to a refreshing 66.4°F (19.1°C). Merna, in September, displays a significant temperature downturn during the night, with an average reading of 44.1°F (6.7°C).Humidity
In Merna, the average relative humidity in September is 44%.Rainfall
In September, in Merna, Wyoming, the rain falls for 8.8 days. Throughout September, 0.83" (21mm) of precipitation is accumulated. Throughout the year, in Merna, there are 109.9 rainfall days, and 10.59" (269mm) of precipitation is accumulated.Snowfall
January through June, September through December are months with snowfall. September is the first month it typically snows. Throughout September, in the average 0.7 snowfall days, it receives 0.59" (15mm) of snow. In Merna, during the entire year, snow falls for 89 days and aggregates up to 43.43" (1103mm) of snow.Daylight
In September, the average length of the day is 12h and 29min.On the first day of September, sunrise is at 6:46 am and sunset at 7:55 pm. On the last day of the month, sunrise is at 7:18 am and sunset at 7:03 pm MDT.
Sunshine
In Merna, the average sunshine in September is 10.7h.UV index
The average daily maximum UV index in September in Merna is 3. A UV Index of 3 to 5 symbolizes a medium health hazard from exposure to the Sun's UV rays for average individuals.Note: The UV index of 3 during September leads to these advisories:
Put precautions into practice - Guidance to elude sunburn is provided. For health reasons, it's advisable to reduce direct sun exposure during peak hours around midday. Loose clothes with a tight weave are optimal for safeguarding yourself against the Sun's rays. Mind this! Nearly twice the UV radiation from the Sun can be reflected by the snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are September temperatures in Merna?
What is the average humidity in September in Merna?
How much does it rain in Merna in September?
When does it start to snow in Merna?
How many hours of daylight does Merna have in September?
When is the sunrise / sunset in September in Merna?
How long on average sun shines in September in Merna?
How high is the UV index in September in Merna?
Average temperature in September
Merna, WY
- Average high temperature in September: 66.4°F
The warmest month (with the highest average high temperature) is July (76.8°F).
The month with the lowest average high temperature is December (23.7°F).
- Average low temperature in September: 44.1°F
The month with the highest average low temperature is July (52°F).
The coldest month (with the lowest average low temperature) is December (5°F).
Average pressure in September
Merna, WY
- Average pressure in September: 29.98"Hg
The month with the highest atmospheric pressure is January (30.28"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in September
Merna, WY
- Average wind speed in September: 5.8mph
The windiest month (with the highest average wind speed) is June (7mph).
The calmest month (with the lowest average wind speed) is December (5.3mph).
Average humidity in September
Merna, WY
- Average humidity in September: 44%
The months with the highest relative humidity are January and February (87%).
The month with the lowest relative humidity is August (39%).
Average rainfall in September
Merna, WY
- Average rainfall in September: 0.83"
The wettest month (with the highest rainfall) is May (1.65").
The driest months (with the least rainfall) are July and August (0.63").
Average rainfall days in September
Merna, WY
- Average rainfall days in September: 8.8 days
The month with the highest number of rainy days is May (14.3 days).
The month with the least rainy days is November (6.9 days).
Average snowfall in September
Merna, WY
- Average snowfall in September: 0.59"
The month with the highest snowfall is April (7.36").
The months with the least snowfall are July and August (0").
Average snowfall days in September
Merna, WY
- Average snowfall days in September: 0.7 days
The months with the highest number of snowfall days are February and March (15.1 days).
The months with the least snowfall days are July and August (0 days).
Average daylight in September /
Average sunshine in September
Merna, WY
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 18min).
The month with the shortest days is December (Average daylight: 9h and 6min).
- Average sunshine in September: 10h and 4min
The month with the most sunshine is July (Average sunshine: 12h and 0min).
The month with the least sunshine is January (Average sunshine: 6h and 12min).
Average sunshine days in September
Merna, WY
- Average sunshine days in September: 17.5 days
The month with the most sunshine days is October (19.6 days).
The month with the least sunshine days is May (10.9 days).
Average UV index in September
Merna, WY
- Average UV index in September: 3
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, April, October, November and December (UV index 2).
Average cloud cover in September
Merna, WY
- Average cloud cover in September: 14
The month with the most cloud cover is February (Cloud cover 41).
The month with the least cloud cover is August (Cloud cover 12).
Average visibility in September
Merna, WY
- 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 and February (4mi).
Merna, Wyoming, USA
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