September weather forecastMira Mesa, CA
September
Weather in September
The first month of the autumn, September, is also a moderately hot month in Mira Mesa, California, with temperature in the range of an average low of 63.7°F (17.6°C) and an average high of 80.4°F (26.9°C).Temperature
As Mira Mesa transitions into September, the average high-temperature stands at a still moderately hot 80.4°F (26.9°C), offering little variation from the preceding month. Throughout September nights, Mira Mesa registers an average low-temperature of 63.7°F (17.6°C).Humidity
In Mira Mesa, the average relative humidity in September is 64%.Rainfall
In Mira Mesa, in September, it is raining for 2.4 days, with typically 0.12" (3mm) of accumulated precipitation. Throughout the year, there are 41.9 rainfall days, and 3.35" (85mm) of precipitation is accumulated.Daylight
The average length of the day in September is 12h and 22min.On the first day of the month, sunrise is at 6:23 am and sunset at 7:12 pm. On the last day of September, sunrise is at 6:42 am and sunset at 6:33 pm PDT.
Sunshine
The average sunshine in September is 10.3h.UV index
The months with the highest UV index are June through September, with an average maximum UV index of 6. A UV Index value of 6 to 7 symbolizes a high health vulnerability from unprotected exposure to Sun's UV rays for ordinary individuals.Note: In September, the maximum UV index of 6 translates into these guidelines:
Eschew overexposure. Those with light skin may suffer burns in fewer than 20 minutes. Limit direct sun exposure especially between 10 a.m. and 4 p.m., when UV radiation is at its peak. However, keep in mind that shade structures may not provide full sun protection. During bright days, sunglasses that offer UVA and UVB defense are recommended.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Mira Mesa, CA
- Average high temperature in September: 80.4°F
The warmest month (with the highest average high temperature) is August (81.1°F).
The month with the lowest average high temperature is December (63.9°F).
- Average low temperature in September: 63.7°F
The month with the highest average low temperature is August (65.3°F).
The coldest month (with the lowest average low temperature) is February (48.7°F).
Average pressure in September
Mira Mesa, CA
- Average pressure in September: 29.88"Hg
The month with the highest atmospheric pressure is January (30.09"Hg).
The month with the lowest atmospheric pressure is June (29.87"Hg).
Average wind speed in September
Mira Mesa, CA
- Average wind speed in September: 4.7mph
The windiest months (with the highest average wind speed) are April and May (5.7mph).
The calmest month (with the lowest average wind speed) is October (4.5mph).
Average humidity in September
Mira Mesa, CA
- Average humidity in September: 64%
The month with the highest relative humidity is May (70%).
The month with the lowest relative humidity is November (56%).
Average rainfall in September
Mira Mesa, CA
- Average rainfall in September: 0.12"
The wettest month (with the highest rainfall) is December (0.63").
The driest month (with the least rainfall) is June (0.04").
Average rainfall days in September
Mira Mesa, CA
- Average rainfall days in September: 2.4 days
The month with the highest number of rainy days is March (6.5 days).
The month with the least rainy days is June (1.3 days).
Average daylight in September /
Average sunshine in September
Mira Mesa, CA
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 18min).
The month with the shortest days is December (Average daylight: 10h and 0min).
- Average sunshine in September: 10h and 18min
The months with the most sunshine are July and August (Average sunshine: 12h and 0min).
The months with the least sunshine are January and December (Average sunshine: 6h and 48min).
Average sunshine days in September
Mira Mesa, CA
- Average sunshine days in September: 25.5 days
The month with the most sunshine days is October (26.1 days).
The month with the least sunshine days is February (21.8 days).
Average UV index in September
Mira Mesa, CA
- Average UV index in September: 6
The months with the highest UV index are June, July, August and September (UV index 6).
The months with the lowest UV index are January, February, March, November and December (UV index 4).
Average cloud cover in September
Mira Mesa, CA
- Average cloud cover in September: 10
The months with the most cloud cover are March and December (Cloud cover 23).
The month with the least cloud cover is August (Cloud cover 7).
Average visibility in September
Mira Mesa, CA
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
