September weather forecastWest Menlo Park, CA
September
Weather in September
September, the first month of the autumn in West Menlo Park, is still a pleasant month, with temperature in the range of an average low of 56.7°F (13.7°C) and an average high of 72.5°F (22.5°C).Temperature
The arrival of September sees a recorded average high-temperature of a still agreeable 72.5°F (22.5°C), showing little divergence from the previous month's conditions. West Menlo Park witnesses an average low-temperature of 56.7°F (13.7°C) throughout the month of September.Humidity
In West Menlo Park, the average relative humidity in September is 71%.Rainfall
In West Menlo Park, during September, the rain falls for 2.4 days and regularly aggregates up to 0.08" (2mm) of precipitation. In West Menlo Park, during the entire year, the rain falls for 57.5 days and collects up to 4.76" (121mm) of precipitation.Daylight
In September, the average length of the day is 12h and 25min.On the first day of September, sunrise is at 6:39 am and sunset at 7:37 pm. On the last day of the month, sunrise is at 7:04 am and sunset at 6:52 pm PDT.
Sunshine
The average sunshine in September in West Menlo Park is 11h.UV index
June through September, with an average maximum UV index of 5, are months with the highest UV index. A UV Index estimate of 3 to 5 represents a medium vulnerability from exposure to the Sun's UV rays for the ordinary person.Note: A maximum high UV index of 5 in September translates into the following recommendations:
Make use of precautions - Shielding skin and eyes from injury is a requirement. To prevent harmful UV exposure, minimize direct contact with the Sun around midday. Select sunglasses that boast both UVA and UVB protection to limit the adverse effects of the sun on the eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
West Menlo Park, CA
- Average high temperature in September: 72.5°F
The warmest month (with the highest average high temperature) is August (73°F).
The month with the lowest average high temperature is December (55.8°F).
- Average low temperature in September: 56.7°F
The months with the highest average low temperature are August and September (56.7°F).
The coldest months (with the lowest average low temperature) are January and February (46.4°F).
Average pressure in September
West Menlo Park, CA
- Average pressure in September: 29.92"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is September (29.92"Hg).
Average wind speed in September
West Menlo Park, CA
- Average wind speed in September: 5.7mph
The windiest month (with the highest average wind speed) is April (7.6mph).
The calmest month (with the lowest average wind speed) is August (5.5mph).
Average humidity in September
West Menlo Park, CA
- Average humidity in September: 71%
The month with the highest relative humidity is March (76%).
The month with the lowest relative humidity is October (68%).
Average rainfall in September
West Menlo Park, CA
- Average rainfall in September: 0.08"
The wettest month (with the highest rainfall) is February (0.98").
The driest month (with the least rainfall) is June (0.04").
Average rainfall days in September
West Menlo Park, CA
- Average rainfall days in September: 2.4 days
The month with the highest number of rainy days is March (10.6 days).
The month with the least rainy days is June (0.9 days).
Average daylight in September /
Average sunshine in September
West Menlo Park, CA
- Average daylight in September: 12h and 24min
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 36min).
- Average sunshine in September: 11h and 0min
The month with the most sunshine is July (Average sunshine: 12h and 0min).
The month with the least sunshine is December (Average sunshine: 5h and 54min).
Average sunshine days in September
West Menlo Park, CA
- Average sunshine days in September: 25.8 days
The months with the most sunshine days are June and July (26.3 days).
The month with the least sunshine days is March (18.3 days).
Average UV index in September
West Menlo Park, CA
- Average UV index in September: 5
The months with the highest UV index are June, July, August and September (UV index 5).
The months with the lowest UV index are February, November and December (UV index 3).
Average cloud cover in September
West Menlo Park, CA
- Average cloud cover in September: 12
The month with the most cloud cover is March (Cloud cover 35).
The month with the least cloud cover is July (Cloud cover 9).
Average visibility in September
West Menlo Park, 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).
