ZIP 06450 Zone 6b

Connecticut · USDA zone 6b, average annual extreme minimum -5°F to 0°F.

Nearest qualified station: MERIDEN MARKHAM MUNI AP, CT US (USW00054788), 3.2 miles from the Census ZCTA internal point for this ZIP.

Median last 32°F is April 26. Median first 32°F is October 16. The 50% growing-season length is 175 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 11Earlier date. A last 32°F on or after this day is common.
50%April 26Median.
10%May 9Later 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 4Earlier date. A first 32°F on or before this day is uncommon.
50%October 16Median.
90%November 1Later 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%194
50%175
90%156

28°F threshold

10%50%90%
Last, on or afterApril 28April 10March 30
First, on or beforeOctober 14October 30November 12
Season at least218 days198 days179 days

36°F threshold

10%50%90%
Last, on or afterMay 21May 7April 24
First, on or beforeSeptember 26October 6October 19
Season at least171 days152 days134 days

Station MERIDEN MARKHAM MUNI AP, CT US (USW00054788). Completeness flag R, 19 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 31.4 m. The same probability language applies to the 28°F and 36°F rows when those dates passed the same quality checks.

Methodology · Connecticut cities