Last frost date in Arnold, MO

Average last frost
April 9

In Arnold, the last spring frost comes around April 9 in an average year. Wait until April 25 if you want 90% odds of no more frost. The first fall frost usually arrives about October 26, which leaves 197 frost-free days. An early freeze before October 14 happens one year in ten.

Safe after (10% risk)
Apr 25
Average first frost
Oct 26
Frost-free season
197 days
Hard freeze (28°F) ends
Mar 31
Next 7 nights in Arnold

No frost in the next 7 nights

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

  1. ThuOct 2247°
  2. FriOct 2345°
  3. SatOct 2447°
  4. SunOct 2549°
  5. MonOct 2648°
  6. TueOct 2746°
  7. WedOct 2847°
JanFebMarAprMayJunJulAugSepOctNovDecLast frost Apr 9First frost Oct 26197 frost-free daysBlue: chance of 32°F frost. Green: average frost-free season.JFMAMJJASOND197 frost-free days
Frost risk through the year at Festus, 13.5 miles from Arnold.

Planting calendar for Arnold

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

Start indoorsPlant outSow outdoorsFall plantingAverage last and first frost
Warm-season crops
JanFebMarAprMayJunJulAugSepOctNovDec
TomatoesApr 16–Apr 30
PumpkinsApr 23–May 7
SunflowersApr 9–Apr 30
CucumbersApr 23–Apr 30
CornApr 16–Apr 30
Sweet potatoesApr 30–May 14
WatermelonApr 23–May 7
Green beansApr 16–May 7
ZucchiniApr 16–Apr 30
OkraApr 30–May 14
PeppersApr 23–May 7
BasilApr 16–Apr 30
Butternut squashApr 16–Apr 30
CantaloupeApr 23–May 7
EggplantApr 23–May 7
Cool-season crops
JanFebMarAprMayJunJulAugSepOctNovDec
PotatoesMar 12–Mar 26
OnionsFeb 26–Mar 19
CarrotsMar 19–Apr 23
LettuceMar 26–Apr 16
BroccoliMar 12–Mar 26
BeetsMar 12–Apr 23
PeasFeb 26–Mar 12
CabbageMar 12–Mar 26
RadishesMar 5–Apr 16
Brussels sproutsMar 26–Apr 9
SpinachFeb 26–Mar 19
CilantroMar 26–Apr 16
KaleMar 12–Mar 26
Collard greensMar 12–Mar 26
TurnipsMar 12–Mar 26
DillApr 9–Apr 23
CeleryApr 16–Apr 23
CauliflowerMar 26–Apr 9
LeeksMar 26–Apr 9
Swiss chardMar 26–Apr 23
ParsleyMar 26–Apr 16
Fall bulbs and garlic
JanFebMarAprMayJunJulAugSepOctNovDec
Tulip bulbsOct 12–Nov 16
GarlicOct 5–Nov 9
Daffodil bulbsSep 28–Nov 9
Perennials
JanFebMarAprMayJunJulAugSepOctNovDec
StrawberriesMar 12–Mar 26
AsparagusMar 12–Mar 26

Frost probabilities

ThresholdSpring, 90% chance laterSpring, 50%Spring, 10%Fall, 10% chance earlierFall, 50%Fall, 90%
Light frost, 32°FMar 25Apr 9Apr 25Oct 14Oct 26Nov 8
Hard freeze, 28°FMar 12Mar 31Apr 15Oct 23Nov 5Nov 23

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 Festus (USC00232850) sits 13.5 miles from the center of Arnold at 600 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 Arnold, MO?

The average last frost date in Arnold is April 9, based on NOAA 1991–2020 climate normals. There is a 10% chance of frost after April 25.

When is the first frost in Arnold?

The first frost in fall usually comes around October 26. One year in ten it arrives before October 14.

How long is the growing season in Arnold?

About 197 days between the average last and first frost.

When should I plant tomatoes in Arnold?

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

Nearby in Missouri

All 41 cities in Missouri