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H I S T O R I C A L   W E A T H E R   D A T A

Average Temperature
 YearJan.Feb.Mar.Apr.MayJun.Jul.Aug.Sep.Oct.Nov.Dec.
F5834.637.547.256.566.475.68078.571.359.749.839.4
C141381319242625211594
Years Charted: 30 Source: National Weather Service, San Francisco
Results based on data collected from 1961 - 1990


Average High Temperature
 YearJan.Feb.Mar.Apr.MayJun.Jul.Aug.Sep.Oct.Nov.Dec.
F66.942.345.956.566.776.284.788.586.980.169.158.347
C19571319242931302620148
Years Charted: 30 Source: National Weather Service, San Francisco
Results based on data collected from 1961 - 1990


Average Low Temperature
 YearJan.Feb.Mar.Apr.MayJun.Jul.Aug.Sep.Oct.Nov.Dec.
F49.226.829.137.746.456.666.571.47062.550.341.131.7
C9-2-13813192121161050
Years Charted: 30 Source: National Weather Service, San Francisco
Results based on data collected from 1961 - 1990


Highest Recorded Temperature
 YearJan.Feb.Mar.Apr.MayJun.Jul.Aug.Sep.Oct.Nov.Dec.
F1047982899599101104103101948675
C40262731353738403938343023
Years Charted: 52 Source: National Weather Service, San Francisco
Results based on data collected through 1993


Lowest Recorded Temperature
 YearJan.Feb.Mar.Apr.MayJun.Jul.Aug.Sep.Oct.Nov.Dec.
F-5-541124344754493929161
C-20-20-15-11-4181293-1-8-17
Years Charted: 52 Source: National Weather Service, San Francisco
Results based on data collected through 1993


Mean Number of Days Below 32F/0C
 TotalJan.Feb.Mar.Apr.MayJun.Jul.Aug.Sep.Oct.Nov.Dec.
Days7022189100000---416
Years Charted: 33 Source: National Weather Service, San Francisco
Results based on data collected through 1993


Average Precipitation
 YearJan.Feb.Mar.Apr.MayJun.Jul.Aug.Sep.Oct.Nov.Dec.
in.38.632.722.713.172.713.663.383.83.913.313.023.123.12
mm981696880689285969984767979
Years Charted: 30 Source: National Weather Service, San Francisco
Results based on data collected from 1961 - 1990


Average Snowfall
 YearJan.Feb.Mar.Apr.MayJun.Jul.Aug.Sep.Oct.Nov.Dec.
in.16.65.35.32.100000000.83.1
mm4211341345300000002078
Years Charted: 50 Source: National Weather Service, San Francisco
Results based on data collected through 1993


Average Wind Speed
 YearJan.Feb.Mar.Apr.MayJun.Jul.Aug.Sep.Oct.Nov.Dec.
mph9.41010.410.910.59.38.98.38.18.48.79.39.6
km/h15161617161414131313131415
Years Charted: 45 Source: National Weather Service, San Francisco
Results based on data collected through 1993


Average Days of Precipitation
 TotalJan.Feb.Mar.Apr.MayJun.Jul.Aug.Sep.Oct.Nov.Dec.
Days11210911101191098799
Years Charted: 52 Source: National Weather Service, San Francisco
Results based on data collected through 1993


Days With Sunshine
 YearJan.Feb.Mar.Apr.MayJun.Jul.Aug.Sep.Oct.Nov.Dec.
%56475155565864626261595146
Years Charted: 45 Source: National Weather Service, San Francisco
Results based on data collected through 1993


Mean Number of Cloudy Days
 TotalJan.Feb.Mar.Apr.MayJun.Jul.Aug.Sep.Oct.Nov.Dec.
Days163161415141411121212121416
Years Charted: 45 Source: National Weather Service, San Francisco
Results based on data collected through 1993


Mean Number of Partly Cloudy Days
 TotalJan.Feb.Mar.Apr.MayJun.Jul.Aug.Sep.Oct.Nov.Dec.
Days1057799101112108887
Years Charted: 45 Source: National Weather Service, San Francisco
Results based on data collected through 1993


Mean Number of Clear Days
 TotalJan.Feb.Mar.Apr.MayJun.Jul.Aug.Sep.Oct.Nov.Dec.
Days9787777879101188
Years Charted: 45 Source: National Weather Service, San Francisco
Results based on data collected through 1993


Average Morning Relative Humidity
 YearJan.Feb.Mar.Apr.MayJun.Jul.Aug.Sep.Oct.Nov.Dec.
%74707070707475768081807572
Years Charted: 33 Source: National Weather Service, San Francisco
Results based on data collected through 1993


Average Afternoon Relative Humidity
 YearJan.Feb.Mar.Apr.MayJun.Jul.Aug.Sep.Oct.Nov.Dec.
%53555250495252535556535457
Years Charted: 33 Source: National Weather Service, San Francisco
Results based on data collected through 1993





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