ZIP 56001 Zone 5a

Minnesota · USDA zone 5a, average annual extreme minimum -20°F to -15°F.

Nearest qualified station: MANKATO, MN US (USC00215073), 2.8 miles from the Census ZCTA internal point for this ZIP.

Median last 32°F is April 30. Median first 32°F is October 9. The 50% growing-season length is 161 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 16Earlier date. A last 32°F on or after this day is common.
50%April 30Median.
10%May 12Later 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 25Earlier date. A first 32°F on or before this day is uncommon.
50%October 9Median.
90%October 22Later 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%179
50%161
90%141

28°F threshold

10%50%90%
Last, on or afterMay 2April 19April 6
First, on or beforeOctober 4October 20November 1
Season at least201 days182 days163 days

36°F threshold

10%50%90%
Last, on or afterMay 23May 8April 26
First, on or beforeSeptember 17September 30October 12
Season at least160 days143 days124 days

Station MANKATO, MN US (USC00215073). Completeness flag R, 15 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 259.1 m. The same probability language applies to the 28°F and 36°F rows when those dates passed the same quality checks.

Methodology · Minnesota cities