ZIP 77304 Zone 9a

Texas · USDA zone 9a, average annual extreme minimum 20°F to 25°F.

Nearest qualified station: CONROE MONTGOMERY CO AP, TX US (USW00053902), 6.4 miles from the Census ZCTA internal point for this ZIP.

Median last 32°F is March 11. Median first 32°F is November 19. The 50% growing-season length is 253 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%February 14Earlier date. A last 32°F on or after this day is common.
50%March 11Median.
10%April 3Later 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%November 1Earlier date. A first 32°F on or before this day is uncommon.
50%November 19Median.
90%December 9Later 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%286
50%253
90%224

28°F threshold

10%50%90%
Last, on or afterMarch 18February 21January 22
First, on or beforeNovember 11December 4January 8
Season at least333 days291 days253 days

36°F threshold

10%50%90%
Last, on or afterApril 15March 24March 3
First, on or beforeOctober 24November 8November 26
Season at least254 days227 days202 days

Station CONROE MONTGOMERY CO AP, TX US (USW00053902). Completeness flag R, 23 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 74.7 m. The same probability language applies to the 28°F and 36°F rows when those dates passed the same quality checks.

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