ZIP 81003 Zone 6a

Colorado · USDA zone 6a, average annual extreme minimum -10°F to -5°F.

Nearest qualified station: PUEBLO RSVR, CO US (USC00056765), 3.6 miles from the Census ZCTA internal point for this ZIP.

Median last 32°F is April 26. Median first 32°F is October 13. The 50% growing-season length is 166 days. The green band runs from the median last frost to the median first frost. Thin ticks mark the 10%, 50%, and 90% dates.

Outside the median season Growing seasonTicks: 10%, 50%, and 90%

Last 32°F in spring

NCEI’s probability is the chance the last spring minimum of 32°F or lower occurs on or after the date.

ProbabilityDateHow to read it
90%April 13Earlier date. A last 32°F on or after this day is common.
50%April 26Median.
10%May 8Later date. A last 32°F on or after this day is uncommon.

First 32°F in fall

NCEI’s probability is the chance the first autumn minimum of 32°F or lower occurs on or before the date.

ProbabilityDateHow to read it
10%September 30Earlier date. A first 32°F on or before this day is uncommon.
50%October 13Median.
90%October 25Later date. A first 32°F on or before this day is common.

32°F growing-season length

Days between the last spring 32°F and the first autumn 32°F. The figure is a length the season meets or exceeds at that probability, from NCEI, not a subtraction done on this site.

Probability the season is at least this longDays
10%184
50%166
90%149

28°F threshold

10%50%90%
Last, on or afterApril 30April 16April 1
First, on or beforeOctober 6October 22November 4
Season at least208 days186 days165 days

36°F threshold

10%50%90%
Last, on or afterMay 19May 6April 24
First, on or beforeSeptember 24October 5October 17
Season at least166 days150 days133 days

Station PUEBLO RSVR, CO US (USC00056765). Completeness flag R, 25 years used for the 32°F dates. NCEI’s annual probability of at least one day at or below 32°F is 100%. Freeze dates are conditional on that threshold occurring. Elevation 1481.6 m. The same probability language applies to the 28°F and 36°F rows when those dates passed the same quality checks.

Methodology · Colorado cities