Last frost date in San Rafael, CA
The average last frost in San Rafael is January 11. By February 25 the chance of another 32°F night drops to 1 in 10. The first fall frost usually arrives about December 21, which leaves 349 frost-free days. An early freeze before December 2 happens one year in ten.
- Safe after (10% risk)
- Feb 25
- Average first frost
- Dec 21
- Frost-free season
- 349 days
- Hard freeze (28°F) ends
- Dec 31
No frost in the next 6 nights
National Weather Service forecast, updated Oct 22, 12:57 UTC
- ThuOct 2251°
- FriOct 2349°
- SatOct 2449°
- SunOct 2551°
- MonOct 2651°
- TueOct 2751°
Planting calendar for San Rafael
Windows count forward or back from the average frost dates above. Click a crop for dates across California.
TomatoesFeb 15–Mar 1
PumpkinsFeb 15–Mar 1
SunflowersFeb 15–Mar 8
CucumbersFeb 22–Mar 1
CornFeb 15–Mar 1
Sweet potatoesFeb 15–Mar 1
WatermelonFeb 15–Mar 1
Green beansFeb 15–Mar 8
ZucchiniFeb 15–Mar 1
OkraFeb 15–Mar 1
PeppersFeb 15–Mar 1
BasilFeb 15–Mar 1
Butternut squashFeb 15–Mar 1
CantaloupeFeb 15–Mar 1
EggplantFeb 15–Mar 1
PotatoesDec 14–Dec 28
OnionsNov 30–Dec 21
CarrotsDec 21–Jan 25
LettuceDec 28–Jan 18
BroccoliDec 14–Dec 28
BeetsDec 14–Jan 25
PeasNov 30–Dec 14
CabbageDec 14–Dec 28
RadishesDec 7–Jan 18
Brussels sproutsDec 28–Jan 11
SpinachNov 30–Dec 21
CilantroDec 28–Jan 18
KaleDec 14–Dec 28
Collard greensDec 14–Dec 28
TurnipsDec 14–Dec 28
DillJan 11–Jan 25
CeleryJan 18–Jan 25
CauliflowerDec 28–Jan 11
LeeksDec 28–Jan 11
Swiss chardDec 28–Jan 25
ParsleyDec 28–Jan 18
Tulip bulbsDec 15–Jan 15
GarlicOct 15–Nov 30
Daffodil bulbsOct 15–Nov 30
StrawberriesDec 14–Dec 28
AsparagusDec 14–Dec 28Frost probabilities
| Threshold | Spring, 90% chance later | Spring, 50% | Spring, 10% | Fall, 10% chance earlier | Fall, 50% | Fall, 90% |
|---|---|---|---|---|---|---|
| Light frost, 32°F | Dec 14 | Jan 11 | Feb 25 | Dec 2 | Dec 21 | Feb 9 |
| Hard freeze, 28°F | Dec 11 | Dec 31 | Feb 21 | Dec 7 | Dec 29 | Feb 18 |
Read the spring 10% column as the date after which only one year in ten still gets frost. That is the safer date for tomatoes, peppers and basil.
Where these numbers come from
NOAA station San Rafael Civic Center (USC00047880) sits 2.0 miles from the center of San Rafael at 120 feet. Its averages cover 1991 to 2020. Low spots, valleys and open fields can keep getting frost a week or two after the station stops; city centers and lakeshores usually get less of it.
Questions
When is the last frost in San Rafael, CA?
The average last frost date in San Rafael is January 11, based on NOAA 1991–2020 climate normals. There is a 10% chance of frost after February 25.
When is the first frost in San Rafael?
The first frost in fall usually comes around December 21. One year in ten it arrives before December 2.
How long is the growing season in San Rafael?
About 349 days between the average last and first frost.
When should I plant tomatoes in San Rafael?
Plant tomato seedlings outside from February 15 to March 1. Start seeds indoors six to eight weeks earlier.