Last frost date in Rosemont, CA

Average last frost
January 12

The average last frost in Rosemont is January 12. By February 8 the chance of another 32°F night drops to 1 in 10. The first fall frost usually arrives about December 16, which leaves 341 frost-free days. An early freeze before November 28 happens one year in ten.

Safe after (10% risk)
Feb 8
Average first frost
Dec 16
Frost-free season
341 days
Hard freeze (28°F) ends
Dec 31
Next 6 nights in Rosemont

No frost in the next 6 nights

National Weather Service forecast, updated Oct 22, 12:57 UTC

  1. ThuOct 2253°
  2. FriOct 2345°
  3. SatOct 2446°
  4. SunOct 2548°
  5. MonOct 2648°
  6. TueOct 2748°
JanFebMarAprMayJunJulAugSepOctNovDecLast frost Jan 12First frost Dec 16341 frost-free daysBlue: chance of 32°F frost. Green: average frost-free season.JFMAMJJASOND341 frost-free days
Frost risk through the year at Sacramento 5 ESE, 3.4 miles from Rosemont.

Planting calendar for Rosemont

Windows count forward or back from the average frost dates above. Click a crop for dates across California.

Start indoorsPlant outSow outdoorsFall plantingAverage last and first frost
Warm-season crops
JanFebMarAprMayJunJulAugSepOctNovDec
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
Cool-season crops
JanFebMarAprMayJunJulAugSepOctNovDec
PotatoesDec 15–Dec 29
OnionsDec 1–Dec 22
CarrotsDec 22–Jan 26
LettuceDec 29–Jan 19
BroccoliDec 15–Dec 29
BeetsDec 15–Jan 26
PeasDec 1–Dec 15
CabbageDec 15–Dec 29
RadishesDec 8–Jan 19
Brussels sproutsDec 29–Jan 12
SpinachDec 1–Dec 22
CilantroDec 29–Jan 19
KaleDec 15–Dec 29
Collard greensDec 15–Dec 29
TurnipsDec 15–Dec 29
DillJan 12–Jan 26
CeleryJan 19–Jan 26
CauliflowerDec 29–Jan 12
LeeksDec 29–Jan 12
Swiss chardDec 29–Jan 26
ParsleyDec 29–Jan 19
Fall bulbs and garlic
JanFebMarAprMayJunJulAugSepOctNovDec
Tulip bulbsDec 15–Jan 15
GarlicOct 15–Nov 30
Daffodil bulbsOct 15–Nov 30
Perennials
JanFebMarAprMayJunJulAugSepOctNovDec
StrawberriesDec 15–Dec 29
AsparagusDec 15–Dec 29

Frost probabilities

ThresholdSpring, 90% chance laterSpring, 50%Spring, 10%Fall, 10% chance earlierFall, 50%Fall, 90%
Light frost, 32°FDec 18Jan 12Feb 8Nov 28Dec 16Jan 14
Hard freeze, 28°FDec 13Dec 31Jan 22Dec 5Dec 25Jan 14

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 Sacramento 5 ESE (USW00023271) sits 3.4 miles from the center of Rosemont at 38 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 Rosemont, CA?

The average last frost date in Rosemont is January 12, based on NOAA 1991–2020 climate normals. There is a 10% chance of frost after February 8.

When is the first frost in Rosemont?

The first frost in fall usually comes around December 16. One year in ten it arrives before November 28.

How long is the growing season in Rosemont?

About 341 days between the average last and first frost.

When should I plant tomatoes in Rosemont?

Plant tomato seedlings outside from February 15 to March 1. Start seeds indoors six to eight weeks earlier.

Nearby in California

All 348 cities in California