Frost Dates for West Allis, WI
In West Allis, WI, the average last spring frost is around Apr 26 and the average first fall frost around Oct 22, for a growing season of about 177 days. For frost-tender plants, wait until May 12, when the chance of frost drops to 10%.
Based on NOAA 1991–2020 records from the West Allis, WI weather station, 2 miles away, elevation 723 ft. Frost can come earlier in low spots and valleys and later near cities and large lakes.
Frost probability by date
Chance of a 32°F frost after the spring date, or before the fall date.
| Chance | Last spring frost | First fall frost |
|---|---|---|
| 10% | May 12 | Oct 7 |
| 20% | May 6 | Oct 12 |
| 30% | May 2 | Oct 16 |
| 40% | Apr 29 | Oct 19 |
| 50% | Apr 26 | Oct 22 |
| 60% | Apr 23 | Oct 25 |
| 70% | Apr 20 | Oct 28 |
| 80% | Apr 16 | Oct 31 |
| 90% | Apr 12 | Nov 3 |
Light frost vs. hard freeze
Average (50%) dates for each temperature. Tender plants are damaged at 36°F; most hardy crops survive until 28°F.
| Temperature | Last in spring | First in fall |
|---|---|---|
| Light frost (36°F) | May 8 | Oct 10 |
| Frost / freeze (32°F) | Apr 26 | Oct 22 |
| Hard freeze (28°F) | Apr 14 | Nov 1 |
Planting calendar for West Allis
Transplant May 3 – May 17
Transplant May 10 – May 24
Transplant May 10 – May 24
Transplant May 3 – May 17
Sow or transplant May 3 – May 17
Sow or transplant May 3 – May 17
Sow or transplant May 10 – May 24
Sow or transplant Mar 29 – Apr 12
Fall sowing Aug 27 – Sep 24
Fall sowing Aug 27 – Sep 17
Fall sowing Aug 13 – Aug 27
Sow or transplant Mar 29 – Apr 12
Fall sowing Aug 13 – Sep 10
Transplant Apr 12 – Apr 26
Fall sowing Jul 30 – Aug 13
Transplant Apr 5 – Apr 19
Fall sowing Jul 30 – Aug 13
Fall sowing Jul 30 – Aug 13
Fall sowing Sep 10 – Oct 1
Fall sowing Aug 13 – Aug 27
Plant Mar 29 – Apr 12
Based on the average last frost (Apr 26) and first frost (Oct 22). The dashed lines mark those dates. Seed packets list days to maturity; adjust for your varieties.