Frost Dates for Mt Hamilton, CA

Frost Dates

Last Spring Frost (50%) iA 50% chance that the last spring frost has already passed by this date. Most gardeners use this as their primary planting guide. May 3
First Fall Frost (50%) iA 50% chance that the first fall frost has occurred by this date. Plan to harvest or protect tender plants before this date. November 18
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

30% Probability iOnly a 30% chance of frost remaining by this date. Use these dates for a safer planting window, especially for tender plants sensitive to cold.

Last Spring Frost May 16
First Fall Frost November 7

Hard Freeze (28°F / -2°C)

Last Spring Hard Freeze April 10
First Fall Hard Freeze December 7
37.34°N, -121.64°W © OpenStreetMap

Growing Season

199 Days May 3 to November 18

USDA Hardiness Zone iHardiness zones indicate which perennial plants can survive winter in your area. For annual vegetables, frost dates and growing season length matter more than hardiness zone.

Zone 9a

Learn more

Temperature

30° 50° 70°
44°
High: 50°
Avg: 44°
Low: 39°
Jan
43°
High: 49°
Avg: 43°
Low: 38°
Feb
45°
High: 51°
Avg: 45°
Low: 39°
Mar
48°
High: 55°
Avg: 48°
Low: 41°
Apr
55°
High: 62°
Avg: 55°
Low: 47°
May
64°
High: 71°
Avg: 64°
Low: 56°
Jun
72°
High: 79°
Avg: 72°
Low: 65°
Jul
72°
High: 79°
Avg: 72°
Low: 65°
Aug
67°
High: 75°
Avg: 67°
Low: 60°
Sep
59°
High: 66°
Avg: 59°
Low: 52°
Oct
49°
High: 55°
Avg: 49°
Low: 43°
Nov
43°
High: 49°
Avg: 43°
Low: 38°
Dec
32°F
Avg High Avg Temp Avg Low Light Frost (32°F)

Precipitation

0" 2" 4" 6" 7.2"
7.0"
7.05"
Jan
7.0"
6.97"
Feb
7.2"
7.24"
Mar
4.8"
4.83"
Apr
3.6"
3.57"
May
0.5"
0.45"
Jun
0.0"
0.00"
Jul
0.0"
0.00"
Aug
0.0"
0.00"
Sep
3.3"
3.33"
Oct
5.3"
5.33"
Nov
6.8"
6.76"
Dec

Sunrise / Sunset

4a7a10a1p4p7p10pNoonJanFebMarAprMayJunJulAugSepOctNovDec10h11h12h13h14h15h14h13h12h11h10h9h
Jan: 7:09 AM – 4:51 PM · 9h 42m
Feb: 6:42 AM – 5:18 PM · 10h 37m
Mar: 6:09 AM – 5:51 PM · 11h 43m
Apr: 5:31 AM – 6:29 PM · 12h 58m
May: 4:60 AM – 7:00 PM · 14h 00m
Jun: 4:43 AM – 7:17 PM · 14h 34m
Jul: 4:50 AM – 7:10 PM · 14h 20m
Aug: 5:17 AM – 6:43 PM · 13h 26m
Sep: 5:53 AM – 6:07 PM · 12h 14m
Oct: 6:30 AM – 5:30 PM · 11h 01m
Nov: 7:01 AM – 4:59 PM · 9h 57m
Dec: 7:17 AM – 4:43 PM · 9h 26m
Daylight Longest: 14h 35m · Shortest: 9h 25m

Nearby Stations

San Jose, CA January 2 - December 25 San Jose, CA January 12 - December 22 Los Gatos, CA February 2 - December 6 Moffett Federal Airfield, CA January 6 - December 23 Gilroy, CA February 24 - November 27 Newark, CAJanuary 1 - December 27

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