39.7294°N/104.8319°W
When to plant in Aurora
Colorado, United States · Cold semi-arid (Köppen BSk)
Last spring frost · safe
May 21
~10% frost risk · typical May 5
First fall frost · safe
Sep 19
~10% frost risk · typical Oct 8
Frost-free days
152
May 5 → Oct 8
Climate zone
Cold semi-arid
Köppen BSk
89/100 confidence
◇ Station-based
The frost date shown is the safe date (~10% frost risk); the typical median is shown alongside. Your microclimate can shift things ±1–2 weeks.
The growing year
Frost-bounded season with crops mapped onto the 12-month axis.
Frost risk Growing Harvest
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
FROST
FROST
GROWING SEASON — 152 DAYS
MAY 5
OCT 8
Full crop calendar
Same climate — Cold semi-arid
Source: Curated · based on NOAA GHCN-Daily 1991–2020 normal · Köppen–Geiger classification (Beck et al. 2023) · crop windows from FAO ECOCROP references. How we calculate this →
Also see frost dates for Aurora.