Tonawanda climate

Tonawanda Frost Dates and Growing Season

NOAA 1991-2020 normals for N Tonawanda, 4.4 km from Tonawanda, elevation 578 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for N Tonawanda. 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 May 6 and the first fall freeze around October 15, a growing season of about 160 days.

Median at 36°F
last May 15, first October 2
Median at 32°F
last May 6, first October 15
Median at 28°F
last April 26, first October 29

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°FMay 27May 24May 21May 18May 15May 13May 10May 7May 2
32°FMay 19May 15May 11May 8May 6May 3Apr 30Apr 27Apr 24
28°FMay 10May 5May 2Apr 29Apr 26Apr 23Apr 20Apr 17Apr 12
24°FApr 28Apr 22Apr 19Apr 16Apr 13Apr 10Apr 7Apr 3Mar 31
20°FApr 16Apr 10Apr 6Apr 3Apr 1Mar 31Mar 27Mar 24Mar 18
16°FApr 4Mar 31Mar 29Mar 26Mar 23Mar 20Mar 17Mar 13Mar 8

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°FSep 20Sep 24Sep 27Sep 30Oct 2Oct 5Oct 8Oct 12Oct 16
32°FSep 30Oct 5Oct 9Oct 12Oct 15Oct 18Oct 20Oct 24Oct 30
28°FOct 12Oct 19Oct 23Oct 26Oct 29Nov 1Nov 3Nov 6Nov 10
24°FOct 28Nov 1Nov 3Nov 6Nov 8Nov 11Nov 15Nov 18Nov 23
20°FNov 6Nov 10Nov 13Nov 17Nov 19Nov 23Nov 26Dec 1Dec 5
16°FNov 16Nov 19Nov 24Nov 27Nov 30Dec 3Dec 6Dec 12Dec 19

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°F158152147143140136132128122
32°F181175169165160156152147141
28°F205198193188184180176171163
24°F233225219214211206202196190
20°F252246241237232229225220213
16°F276268262258253249244238231

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
100% of years
20°F or colder
100% of years
16°F or colder
100% 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
6,622
Cooling degree days, base 65°F
542
Growing degree days, base 40°F
4,628
Growing degree days, base 45°F
3,533
Growing degree days, base 50°F
2,582
Growing degree days, base 55°F
1,764
Growing degree days, base 60°F
1,077

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,24101
February1,08601
March963010
April595150
May26725253
June52109507
July9193649
August16160609
September13051373
October4433112
November752015
December1,06801

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 4.4 km from Tonawanda. Low ground, valleys and open fields freeze earlier and later than a town center or a hillside.

More

Sources

NOAA NCEI U.S. Climate Normals, 1991-2020, annual and seasonal normals for station USC00306047 (N Tonawanda). Public domain.