Fort Worth climate

Fort Worth Frost Dates and Growing Season

NOAA 1991-2020 normals for Ft Worth Wsfo, 12.3 km from Fort Worth, elevation 644 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Ft Worth Wsfo. A median date has an even chance of a later freeze in spring, or an earlier one in fall.

The last spring freeze typically comes around March 10 and the first fall freeze around November 20, a growing season of about 255 days.

Median at 36°F
last March 26, first November 9
Median at 32°F
last March 10, first November 20
Median at 28°F
last February 26, first December 1

Last freeze in spring

The chance of a later freeze than the date shown. At 10 percent, one spring in ten still freezes after the date; planting after the 10 percent date for 32°F is the cautious choice.

Threshold10%20%30%40%50%60%70%80%90%
36°FApr 16Apr 8Apr 3Mar 31Mar 26Mar 21Mar 17Mar 13Mar 6
32°FMar 31Mar 23Mar 18Mar 14Mar 10Mar 7Mar 3Feb 27Feb 21
28°FMar 17Mar 10Mar 6Mar 2Feb 26Feb 22Feb 18Feb 10Feb 2
24°FMar 8Mar 1Feb 23Feb 16Feb 10Feb 5Jan 31Jan 25Jan 16
20°FFeb 27Feb 16Feb 9Feb 2Jan 28Jan 21Jan 15Jan 5Dec 25
16°FFeb 16Feb 7Feb 1Jan 23Jan 17Jan 10Jan 2Dec 29Dec 17

First freeze in fall

The chance of an earlier freeze than the date shown. At 10 percent, one fall in ten freezes before the date.

Threshold10%20%30%40%50%60%70%80%90%
36°FOct 26Nov 1Nov 4Nov 7Nov 9Nov 12Nov 16Nov 20Nov 26
32°FNov 4Nov 8Nov 13Nov 17Nov 20Nov 24Nov 28Dec 1Dec 8
28°FNov 13Nov 18Nov 24Nov 28Dec 1Dec 5Dec 9Dec 15Dec 23
24°FNov 24Dec 1Dec 6Dec 12Dec 18Dec 24Dec 30Jan 4Jan 15
20°FDec 5Dec 13Dec 21Dec 26Jan 1Jan 5Jan 12Jan 19Feb 1
16°FDec 13Dec 20Dec 28Jan 1Jan 6Jan 13Jan 19Jan 31Feb 8

Growing season length

Days between the last spring and first fall freeze at each threshold, with the chance of a season at least that long.

Threshold10%20%30%40%50%60%70%80%90%
36°F256247240235230224219213206
32°F281272265259255249244237228
28°F308298290285278273266260251
24°F345333321313307300294286276
20°F365365355346340331323311299
16°F365365365365365364353343325

How often it gets that cold

The share of years with at least one night at or below each temperature.

36°F or colder
100% of years
32°F or colder
100% of years
28°F or colder
100% of years
24°F or colder
99% of years
20°F or colder
81% of years
16°F or colder
43% of years

Degree days

A degree day is one degree of the daily mean temperature beyond a base, for one day. Heating degree days count cold (the fuel a house burns), cooling degree days heat, growing degree days the warmth a crop needs; each crop has its own base.

Heating degree days, base 65°F
2,414
Cooling degree days, base 65°F
2,577
Growing degree days, base 40°F
9,436
Growing degree days, base 45°F
7,783
Growing degree days, base 50°F
6,256
Growing degree days, base 55°F
4,871
Growing degree days, base 60°F
3,640

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January606268
February4466108
March27629263
April10385437
May15256705
June0469919
July06081,072
August06001,064
September5368813
October87130513
November31120212
December565481

What this means

NOAA computes these from the daily lows at the station over 1991-2020, fitting the dates of each year's last and first freeze to a distribution, so a date can be stated at any level of risk. 36°F is a frost risk for tender plants on a clear, calm night, since the ground cools below the air above it; 32°F is a freeze; 28°F is a hard freeze that kills most annuals.

The station is 12.3 km from Fort Worth. Low ground, valleys and open fields freeze earlier and later than a town center or a hillside.

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Sources

NOAA NCEI U.S. Climate Normals, 1991-2020, annual and seasonal normals for station USC00413285 (Ft Worth Wsfo). Public domain.