Tool climate

Tool Frost Dates and Growing Season

NOAA 1991-2020 normals for Corsicana, 33.9 km from Tool, elevation 449 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Corsicana. 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 14 and the first fall freeze around November 16, a growing season of about 246 days.

Median at 36°F
last March 30, first November 6
Median at 32°F
last March 14, first November 16
Median at 28°F
last March 2, first November 28

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 9Apr 5Apr 1Mar 30Mar 26Mar 21Mar 16Mar 8
32°FApr 4Mar 29Mar 23Mar 18Mar 14Mar 10Mar 5Feb 28Feb 23
28°FMar 23Mar 16Mar 11Mar 6Mar 2Feb 27Feb 21Feb 13Feb 4
24°FMar 11Mar 4Feb 28Feb 21Feb 14Feb 6Feb 1Jan 26Jan 14
20°FMar 1Feb 16Feb 9Feb 2Jan 29Jan 22Jan 15Jan 5Dec 24
16°FFeb 17Feb 4Jan 31Jan 23Jan 17Jan 11Jan 5Dec 31Dec 20

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 22Oct 27Oct 31Nov 3Nov 6Nov 9Nov 13Nov 17Nov 22
32°FNov 1Nov 4Nov 8Nov 12Nov 16Nov 19Nov 24Nov 30Dec 4
28°FNov 8Nov 14Nov 19Nov 23Nov 28Dec 2Dec 6Dec 12Dec 21
24°FNov 19Nov 27Dec 2Dec 8Dec 13Dec 21Dec 27Jan 4Jan 16
20°FDec 2Dec 11Dec 17Dec 25Jan 1Jan 6Jan 14Jan 23Feb 6
16°FDec 14Dec 23Jan 1Jan 4Jan 9Jan 15Jan 19Jan 28Feb 7

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°F249239233227222217212206197
32°F274263257251246241235228219
28°F304294286279273266259253244
24°F343331320312305299290280267
20°F365365352344337332323314301
16°F365365365365365363353343331

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
97% of years
20°F or colder
78% of years
16°F or colder
37% 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
2,319
Cooling degree days, base 65°F
2,595
Growing degree days, base 40°F
9,516
Growing degree days, base 45°F
7,852
Growing degree days, base 50°F
6,314
Growing degree days, base 55°F
4,919
Growing degree days, base 60°F
3,677

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January590370
February4317109
March27527260
April10385437
May15255705
June0456906
July05911,056
August06041,069
September4389835
October77145537
November29928233
December525697

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 33.9 km from Tool. 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 USC00412019 (Corsicana). Public domain.