ZIP 48502 Zone 6a

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

Nearest qualified station: FLINT 7W, MI US (USC00202851), 4.4 miles from the Census ZCTA internal point for this ZIP.

Median last 32°F is May 3. Median first 32°F is October 13. The 50% growing-season length is 162 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 20Earlier date. A last 32°F on or after this day is common.
50%May 3Median.
10%May 20Later 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 27Later 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%181
50%162
90%142

28°F threshold

10%50%90%
Last, on or afterMay 9April 22April 8
First, on or beforeOctober 12October 27November 9
Season at least206 days186 days163 days

36°F threshold

10%50%90%
Last, on or afterMay 29May 14April 29
First, on or beforeSeptember 20October 2October 13
Season at least159 days141 days122 days

Station FLINT 7W, MI US (USC00202851). 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 207 m. The same probability language applies to the 28°F and 36°F rows when those dates passed the same quality checks.

Methodology · Michigan cities