ZIP 46216 Zone 6a

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

Nearest qualified station: CASTLETON 2 S, IN US (USC00121326), 2.4 miles from the Census ZCTA internal point for this ZIP.

Median last 32°F is April 18. Median first 32°F is October 26. The 50% growing-season length is 190 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 3Earlier date. A last 32°F on or after this day is common.
50%April 18Median.
10%May 6Later 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%October 12Earlier date. A first 32°F on or before this day is uncommon.
50%October 26Median.
90%November 7Later 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%211
50%190
90%166

28°F threshold

10%50%90%
Last, on or afterApril 24April 5March 21
First, on or beforeOctober 25November 5November 21
Season at least235 days213 days192 days

36°F threshold

10%50%90%
Last, on or afterMay 16April 30April 14
First, on or beforeOctober 3October 16October 27
Season at least187 days167 days147 days

Station CASTLETON 2 S, IN US (USC00121326). Completeness flag R, 11 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 251.2 m. The same probability language applies to the 28°F and 36°F rows when those dates passed the same quality checks.

Methodology · Indiana cities