Last frost date in Mukilteo, WA

Average last frost
March 9

The average last frost in Mukilteo is March 9. By March 29 the chance of another 32°F night drops to 1 in 10. The first fall frost usually arrives about November 17, which leaves 250 frost-free days. An early freeze before October 31 happens one year in ten.

Safe after (10% risk)
Mar 29
Average first frost
Nov 17
Frost-free season
250 days
Hard freeze (28°F) ends
Feb 13
Next 6 nights in Mukilteo

No frost in the next 6 nights

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

  1. ThuOct 2246°
  2. FriOct 2342°
  3. SatOct 2444°
  4. SunOct 2545°
  5. MonOct 2645°
  6. TueOct 2744°
JanFebMarAprMayJunJulAugSepOctNovDecLast frost Mar 9First frost Nov 17250 frost-free daysBlue: chance of 32°F frost. Green: average frost-free season.JFMAMJJASOND250 frost-free days
Frost risk through the year at Everett Snohomish Airport, 1.1 miles from Mukilteo.

Planting calendar for Mukilteo

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

Start indoorsPlant outSow outdoorsFall plantingAverage last and first frost
Warm-season crops
JanFebMarAprMayJunJulAugSepOctNovDec
TomatoesMar 16–Mar 30
PumpkinsMar 23–Apr 6
SunflowersMar 9–Mar 30
CucumbersMar 23–Mar 30
CornMar 16–Mar 30
Sweet potatoesMar 30–Apr 13
WatermelonMar 23–Apr 6
Green beansMar 16–Apr 6
ZucchiniMar 16–Mar 30
OkraMar 30–Apr 13
PeppersMar 23–Apr 6
BasilMar 16–Mar 30
Butternut squashMar 16–Mar 30
CantaloupeMar 23–Apr 6
EggplantMar 23–Apr 6
Cool-season crops
JanFebMarAprMayJunJulAugSepOctNovDec
PotatoesFeb 9–Feb 23
OnionsJan 26–Feb 16
CarrotsFeb 16–Mar 23
LettuceFeb 23–Mar 16
BroccoliFeb 9–Feb 23
BeetsFeb 9–Mar 23
PeasJan 26–Feb 9
CabbageFeb 9–Feb 23
RadishesFeb 2–Mar 16
Brussels sproutsFeb 23–Mar 9
SpinachJan 26–Feb 16
CilantroFeb 23–Mar 16
KaleFeb 9–Feb 23
Collard greensFeb 9–Feb 23
TurnipsFeb 9–Feb 23
DillMar 9–Mar 23
CeleryMar 16–Mar 23
CauliflowerFeb 23–Mar 9
LeeksFeb 23–Mar 9
Swiss chardFeb 23–Mar 23
ParsleyFeb 23–Mar 16
Fall bulbs and garlic
JanFebMarAprMayJunJulAugSepOctNovDec
Tulip bulbsNov 3–Dec 8
GarlicOct 15–Nov 30
Daffodil bulbsOct 15–Nov 30
Perennials
JanFebMarAprMayJunJulAugSepOctNovDec
StrawberriesFeb 9–Feb 23
AsparagusFeb 9–Feb 23

Frost probabilities

ThresholdSpring, 90% chance laterSpring, 50%Spring, 10%Fall, 10% chance earlierFall, 50%Fall, 90%
Light frost, 32°FFeb 15Mar 9Mar 29Oct 31Nov 17Dec 7
Hard freeze, 28°FJan 1Feb 13Mar 9Nov 15Dec 6Jan 8

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 Everett Snohomish Airport (USW00024222) sits 1.1 miles from the center of Mukilteo at 606 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 Mukilteo, WA?

The average last frost date in Mukilteo is March 9, based on NOAA 1991–2020 climate normals. There is a 10% chance of frost after March 29.

When is the first frost in Mukilteo?

The first frost in fall usually comes around November 17. One year in ten it arrives before October 31.

How long is the growing season in Mukilteo?

About 250 days between the average last and first frost.

When should I plant tomatoes in Mukilteo?

Plant tomato seedlings outside from March 16 to March 30. Start seeds indoors six to eight weeks earlier.

Nearby in Washington

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