Last frost date in Mountain House, CA
The average last frost in Mountain House is January 19. By February 17 the chance of another 32°F night drops to 1 in 10. The first fall frost usually arrives about December 10, which leaves 330 frost-free days. An early freeze before November 26 happens one year in ten.
- Safe after (10% risk)
- Feb 17
- Average first frost
- Dec 10
- Frost-free season
- 330 days
- Hard freeze (28°F) ends
- Jan 1
No frost in the next 6 nights
National Weather Service forecast, updated Oct 22, 12:57 UTC
- ThuOct 2255°
- FriOct 2352°
- SatOct 2453°
- SunOct 2554°
- MonOct 2653°
- TueOct 2753°
Planting calendar for Mountain House
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 22–Jan 5
OnionsDec 8–Dec 29
CarrotsDec 29–Feb 2
LettuceJan 5–Jan 26
BroccoliDec 22–Jan 5
BeetsDec 22–Feb 2
PeasDec 8–Dec 22
CabbageDec 22–Jan 5
RadishesDec 15–Jan 26
Brussels sproutsJan 5–Jan 19
SpinachDec 8–Dec 29
CilantroJan 5–Jan 26
KaleDec 22–Jan 5
Collard greensDec 22–Jan 5
TurnipsDec 22–Jan 5
DillJan 19–Feb 2
CeleryJan 26–Feb 2
CauliflowerJan 5–Jan 19
LeeksJan 5–Jan 19
Swiss chardJan 5–Feb 2
ParsleyJan 5–Jan 26
Tulip bulbsDec 15–Jan 15
GarlicOct 15–Nov 30
Daffodil bulbsOct 15–Nov 30
StrawberriesDec 22–Jan 5
AsparagusDec 22–Jan 5Frost probabilities
| Threshold | Spring, 90% chance later | Spring, 50% | Spring, 10% | Fall, 10% chance earlier | Fall, 50% | Fall, 90% |
|---|---|---|---|---|---|---|
| Light frost, 32°F | Dec 25 | Jan 19 | Feb 17 | Nov 26 | Dec 10 | Jan 7 |
| Hard freeze, 28°F | Dec 12 | Jan 1 | Jan 22 | Dec 4 | Dec 22 | Jan 10 |
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 Tracy Pumping Plt (USC00049001) sits 2.7 miles from the center of Mountain House at 61 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 Mountain House, CA?
The average last frost date in Mountain House is January 19, based on NOAA 1991–2020 climate normals. There is a 10% chance of frost after February 17.
When is the first frost in Mountain House?
The first frost in fall usually comes around December 10. One year in ten it arrives before November 26.
How long is the growing season in Mountain House?
About 330 days between the average last and first frost.
When should I plant tomatoes in Mountain House?
Plant tomato seedlings outside from February 15 to March 1. Start seeds indoors six to eight weeks earlier.