FrostDateByZip

Frost dates for 16048North Washington, PA

The average last spring frost in North Washington is May 7 and the average first fall frost is October 14, giving a typical growing season of about 158 days. Dates are based on NOAA 1991-2020 climate normals.

Average last spring frost
May 7

Safer after May 25 (1-in-10 risk)

Average first fall frost
Oct 14

Possible by Oct 1 (1-in-10 risk)

Growing season
158 days

Last frost typically in 185 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)May 1 · May 20 · Jun 2Sep 17 · Oct 1 · Oct 15135 days100%
Frost / freeze (32°F)Apr 22 · May 7 · May 25Oct 1 · Oct 14 · Oct 30158 days100%
Hard freeze (28°F)Apr 11 · Apr 26 · May 15Oct 10 · Oct 27 · Nov 10183 days100%

Planting calendar for North Washington

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 indoorsApr 6 – Jun 12
TomatoesTransplant outdoorsMay 23 – Jun 24
PeppersStart seeds indoorsApr 6 – May 7
PeppersTransplant outdoorsJun 6 – Jul 7
EggplantStart seeds indoorsApr 23 – May 22
EggplantTransplant outdoorsJun 6 – Jul 7
CucumbersSow outdoorsJun 6 – Jul 4
Summer squashSow outdoorsMay 23 – Jul 7
Winter squash & pumpkinsSow outdoorsJun 6 – Jul 7
Snap beansSow outdoorsMay 23 – Jul 27
Sweet cornSow outdoorsMay 23 – Jun 24
Watermelon & cantaloupeSow outdoorsJun 6 – Jul 7
OkraSow outdoorsMay 30 – Jun 22
PeasSow outdoors (spring)Apr 6 – May 22
PotatoesPlant outdoors (spring)Apr 6 – Jun 6
OnionsStart seeds indoors (spring)Feb 23 – Mar 22
OnionsTransplant outdoors (spring)Apr 23 – May 22
BroccoliStart seeds indoors (spring)Mar 19 – Apr 22
BroccoliTransplant outdoors (spring)Apr 23 – May 22
BroccoliStart seeds indoors (fall)Jun 14 – Jun 24
BroccoliTransplant outdoors (fall)Jul 14 – Jul 25
CabbageStart seeds indoors (spring)Mar 9 – Apr 6
CabbageTransplant outdoors (spring)Apr 6 – May 7
CabbageStart seeds indoors (fall)Jun 4 – Jul 4
CabbageTransplant outdoors (fall)Jul 4 – Aug 4
Leaf lettuceSow outdoors (spring)Apr 6 – Jun 22
Leaf lettuceSow outdoors (fall)Jul 4 – Aug 20
SpinachSow outdoors (spring)Mar 30 – May 13
SpinachSow outdoors (fall)Jul 21 – Aug 25
RadishesSow outdoors (spring)Apr 6 – May 27
RadishesSow outdoors (fall)Jul 4 – Sep 4
KaleSow outdoors (spring)Apr 23 – May 13
KaleSow outdoors (fall)Jun 27 – Aug 4
CarrotsSow outdoors (spring)May 7 – Jun 22
CarrotsSow outdoors (fall)Jun 4 – Jul 20
GarlicPlant outdoors (fall)Oct 4 – Nov 4

Where these dates come from

ZIP code 16048 is matched to the NOAA station Slippery Rock 1 Ssw, PA, 21 km away, at 1,260 ft elevation (203 ft lower than the ZIP code's center). Nearby stations for comparison:

StationElevationAvg last frostAvg first frost
Slippery Rock 1 Ssw, PA (used)1,260 ftMay 7Oct 14
Butler 2 Sw, PA1,000 ftMay 7Oct 14
Clarion 3 Sw, PA1,040 ftMay 9Oct 11
Franklin, PA1,015 ftMay 2Oct 23

Frost dates near North Washington

Frequently asked questions

When is the last frost in North Washington, PA?
For ZIP code 16048, the average last spring frost (32°F) is May 7, based on NOAA 1991-2020 climate normals for the Slippery Rock 1 Ssw, PA weather station. There is a 1-in-10 chance of a frost after May 25.
When is the first frost in North Washington, PA?
The average first fall frost (32°F) is October 14. There is a 1-in-10 chance of frost by October 1, so tender plants are at risk from that point on.
How long is the growing season in 16048?
In half of years, the frost-free season (between the last and first 32°F frost) is at least 158 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.