Last frost date in Monroe, WA

Average last frost
April 17

Expect the last frost in Monroe around April 17. Frost after May 7 happens in only one year out of ten. The first fall frost usually arrives about October 23, which leaves 188 frost-free days. An early freeze before October 7 happens one year in ten.

Safe after (10% risk)
May 7
Average first frost
Oct 23
Frost-free season
188 days
Hard freeze (28°F) ends
Mar 26
Next 6 nights in Monroe

Frost possible in low spots Fri night, low 35°F

National Weather Service forecast, updated Oct 22, 12:24 UTC

  1. ThuOct 2239°
  2. FriOct 2335°possible frost
  3. SatOct 2439°
  4. SunOct 2538°
  5. MonOct 2638°
  6. TueOct 2738°
JanFebMarAprMayJunJulAugSepOctNovDecLast frost Apr 17First frost Oct 23188 frost-free daysBlue: chance of 32°F frost. Green: average frost-free season.JFMAMJJASOND188 frost-free days
Frost risk through the year at Monroe, 1.1 miles from Monroe.

Planting calendar for Monroe

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
TomatoesApr 24–May 8
PumpkinsMay 1–May 15
SunflowersApr 17–May 8
CucumbersMay 1–May 8
CornApr 24–May 8
Sweet potatoesMay 8–May 22
WatermelonMay 1–May 15
Green beansApr 24–May 15
ZucchiniApr 24–May 8
OkraMay 8–May 22
PeppersMay 1–May 15
BasilApr 24–May 8
Butternut squashApr 24–May 8
CantaloupeMay 1–May 15
EggplantMay 1–May 15
Cool-season crops
JanFebMarAprMayJunJulAugSepOctNovDec
PotatoesMar 20–Apr 3
OnionsMar 6–Mar 27
CarrotsMar 27–May 1
LettuceApr 3–Apr 24
BroccoliMar 20–Apr 3
BeetsMar 20–May 1
PeasMar 6–Mar 20
CabbageMar 20–Apr 3
RadishesMar 13–Apr 24
Brussels sproutsApr 3–Apr 17
SpinachMar 6–Mar 27
CilantroApr 3–Apr 24
KaleMar 20–Apr 3
Collard greensMar 20–Apr 3
TurnipsMar 20–Apr 3
DillApr 17–May 1
CeleryApr 24–May 1
CauliflowerApr 3–Apr 17
LeeksApr 3–Apr 17
Swiss chardApr 3–May 1
ParsleyApr 3–Apr 24
Fall bulbs and garlic
JanFebMarAprMayJunJulAugSepOctNovDec
Tulip bulbsOct 9–Nov 13
GarlicOct 2–Nov 6
Daffodil bulbsSep 25–Nov 6
Perennials
JanFebMarAprMayJunJulAugSepOctNovDec
StrawberriesMar 20–Apr 3
AsparagusMar 20–Apr 3

Frost probabilities

ThresholdSpring, 90% chance laterSpring, 50%Spring, 10%Fall, 10% chance earlierFall, 50%Fall, 90%
Light frost, 32°FMar 29Apr 17May 7Oct 7Oct 23Nov 9
Hard freeze, 28°FMar 6Mar 26Apr 14Oct 20Nov 8Nov 26

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 Monroe (USC00455525) sits 1.1 miles from the center of Monroe 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 Monroe, WA?

The average last frost date in Monroe is April 17, based on NOAA 1991–2020 climate normals. There is a 10% chance of frost after May 7.

When is the first frost in Monroe?

The first frost in fall usually comes around October 23. One year in ten it arrives before October 7.

How long is the growing season in Monroe?

About 188 days between the average last and first frost.

When should I plant tomatoes in Monroe?

Plant tomato seedlings outside from April 24 to May 8. Start seeds indoors six to eight weeks earlier.

Nearby in Washington

All 76 cities in Washington