FrostDateByZip

Frost dates for 98325Chimacum, WA

The average last spring frost in Chimacum is March 1 and the average first fall frost is November 28, giving a typical growing season of about 274 days. Dates are based on NOAA 1991-2020 climate normals.

Average last spring frost
Mar 1

Safer after Mar 23 (1-in-10 risk)

Average first fall frost
Nov 28

Possible by Nov 9 (1-in-10 risk)

Growing season
274 days

First frost typically in 25 days

Frost risk by date

NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.

Spring dates: chance of a frost AFTER the date. Fall dates: chance of a frost BEFORE the date.
TemperatureLast spring: 90% / 50% / 10% chanceFirst fall: 10% / 50% / 90% chanceGrowing season (50%)Years with at least one
Light frost (36°F)Mar 10 · Mar 31 · Apr 26Oct 19 · Nov 9 · Nov 26221 days100%
Frost / freeze (32°F)Feb 3 · Mar 1 · Mar 23Nov 9 · Nov 28 · Dec 26274 days100%
Hard freeze (28°F)Dec 14 · Feb 1 · Mar 3Nov 20 · Dec 19 · Feb 6324 days88%

Planting calendar for Chimacum

Planting windows from the University of Maryland Extension calendar, shifted to your average frost dates. Use them as a starting point and adjust for seed packet instructions and local conditions.

CropTaskWindow
TomatoesStart seeds indoorsJan 29 – Apr 6
TomatoesTransplant outdoorsMar 17 – Aug 8
PeppersStart seeds indoorsJan 29 – Mar 1
PeppersTransplant outdoorsMar 31 – May 1
EggplantStart seeds indoorsFeb 15 – Mar 16
EggplantTransplant outdoorsMar 31 – May 1
CucumbersSow outdoorsMar 31 – Aug 18
Summer squashSow outdoorsMar 17 – May 1
Winter squash & pumpkinsSow outdoorsMar 31 – May 1
Snap beansSow outdoorsMar 17 – Sep 10
Sweet cornSow outdoorsMar 17 – Aug 8
Watermelon & cantaloupeSow outdoorsMar 31 – May 1
OkraSow outdoorsMar 24 – Apr 16
PeasSow outdoors (spring)Jan 29 – Mar 16
PotatoesPlant outdoors (spring)Jan 29 – Mar 31
OnionsStart seeds indoors (spring)Dec 18 – Jan 14
OnionsTransplant outdoors (spring)Feb 15 – Mar 16
BroccoliStart seeds indoors (spring)Jan 11 – Feb 14
BroccoliTransplant outdoors (spring)Feb 15 – Mar 16
BroccoliStart seeds indoors (fall)Jul 29 – Aug 8
BroccoliTransplant outdoors (fall)Aug 28 – Sep 8
CabbageStart seeds indoors (spring)Jan 1 – Jan 29
CabbageTransplant outdoors (spring)Jan 29 – Mar 1
CabbageStart seeds indoors (fall)Jul 19 – Aug 18
CabbageTransplant outdoors (fall)Aug 18 – Sep 18
Leaf lettuceSow outdoors (spring)Jan 29 – Apr 16
Leaf lettuceSow outdoors (fall)Aug 18 – Oct 4
SpinachSow outdoors (spring)Jan 22 – Mar 7
SpinachSow outdoors (fall)Sep 4 – Oct 9
RadishesSow outdoors (spring)Jan 29 – Mar 21
RadishesSow outdoors (fall)Aug 18 – Oct 19
KaleSow outdoors (spring)Feb 15 – Mar 7
KaleSow outdoors (fall)Aug 11 – Sep 18
CarrotsSow outdoors (spring)Mar 1 – Apr 16
CarrotsSow outdoors (fall)Jul 19 – Sep 3
GarlicPlant outdoors (fall)Nov 18 – Dec 19

Where these dates come from

ZIP code 98325 is matched to the NOAA station Port Townsend, WA, 14.6 km away, at 100 ft elevation (156 ft lower than the ZIP code's center). Nearby stations for comparison:

StationElevationAvg last frostAvg first frost
Port Townsend, WA (used)100 ftMar 1Nov 28
Quilcene 2 Sw, WA123 ftApr 11Oct 28
Sequim 2 E, WA50 ftApr 21Oct 20
Coupeville 1 S, WA50 ftMar 17Nov 11

Frost dates near Chimacum

Frequently asked questions

When is the last frost in Chimacum, WA?
For ZIP code 98325, the average last spring frost (32°F) is March 1, based on NOAA 1991-2020 climate normals for the Port Townsend, WA weather station. There is a 1-in-10 chance of a frost after March 23.
When is the first frost in Chimacum, WA?
The average first fall frost (32°F) is November 28. There is a 1-in-10 chance of frost by November 9, so tender plants are at risk from that point on.
How long is the growing season in 98325?
In half of years, the frost-free season (between the last and first 32°F frost) is at least 274 days long.
Are these frost dates a forecast?
No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.