September weather forecastTierrasanta, CA
September
Weather in September
The first month of the autumn, September, is also a moderately hot month in Tierrasanta, California, with an average temperature ranging between min 64.4°F (18°C) and max 78.6°F (25.9°C).Temperature
Upon the beginning of September, Tierrasanta's high-temperatures register at a still warm 78.6°F (25.9°C), closely mirroring the preceding month. During September, the average low-temperature is recorded at a comfortable 64.4°F (18°C).Humidity
The average relative humidity in September is 65%.Rainfall
In Tierrasanta, California, during September, the rain falls for 4.2 days and regularly aggregates up to 0.31" (8mm) of precipitation. Throughout the year, there are 57.9 rainfall days, and 7.48" (190mm) of precipitation is accumulated.Daylight
The average length of the day in September in Tierrasanta is 12h and 22min.On the first day of September in Tierrasanta, sunrise is at 6:23 am and sunset at 7:12 pm. On the last day of the month, sunrise is at 6:42 am and sunset at 6:33 pm PDT.
Sunshine
The average sunshine in September is 10.3h.UV index
July through September, with an average maximum UV index of 6, are months with the highest UV index in Tierrasanta. A UV Index reading of 6 to 7 represents a high health vulnerability from unsafe exposure to UV radiation for the ordinary person.Note: During September, 6 as the daily maximum UV index converts into the following advice:
Avert overexposure. Light-skinned people might experience burning in less than 20 minutes. Avoid direct Sun exposure and stay in the shade between 10 a.m. and 4 p.m., a time when UV radiation is most intense, noting that not all shade structures offer full protection. Sun-protective clothing, a long-sleeved shirt and pants, a wide-brimmed hat, and UVA and UVB-blocking sunglasses are particularly helpful in blocking UV radiation's harmful effects.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Tierrasanta, CA
- Average high temperature in September: 78.6°F
The warmest month (with the highest average high temperature) is August (79.3°F).
The month with the lowest average high temperature is December (63.5°F).
- Average low temperature in September: 64.4°F
The month with the highest average low temperature is August (65.8°F).
The coldest month (with the lowest average low temperature) is February (50.2°F).
Average pressure in September
Tierrasanta, CA
- Average pressure in September: 29.88"Hg
The month with the highest atmospheric pressure is January (30.09"Hg).
The months with the lowest atmospheric pressure are June and September (29.88"Hg).
Average wind speed in September
Tierrasanta, CA
- Average wind speed in September: 5mph
The windiest month (with the highest average wind speed) is April (6mph).
The calmest month (with the lowest average wind speed) is October (4.8mph).
Average humidity in September
Tierrasanta, CA
- Average humidity in September: 65%
The months with the highest relative humidity are May and June (71%).
The month with the lowest relative humidity is November (57%).
Average rainfall in September
Tierrasanta, CA
- Average rainfall in September: 0.31"
The wettest month (with the highest rainfall) is February (1.46").
The driest month (with the least rainfall) is June (0.12").
Average rainfall days in September
Tierrasanta, CA
- Average rainfall days in September: 4.2 days
The month with the highest number of rainy days is March (7.1 days).
The month with the least rainy days is June (2.2 days).
Average daylight in September /
Average sunshine in September
Tierrasanta, 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 month with the most sunshine is July (Average sunshine: 12h and 0min).
The month with the least sunshine is December (Average sunshine: 6h and 48min).
Average sunshine days in September
Tierrasanta, CA
- Average sunshine days in September: 22.4 days
The month with the most sunshine days is January (24.8 days).
The month with the least sunshine days is February (20.2 days).
Average UV index in September
Tierrasanta, CA
- Average UV index in September: 6
The months with the highest UV index are 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
Tierrasanta, CA
- Average cloud cover in September: 11
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 8).
Average visibility in September
Tierrasanta, 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).
