Warwick climate

Warwick Frost Dates and Growing Season

NOAA 1991-2020 normals for Tully Lake, 10.5 km from Warwick, elevation 680 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Tully Lake. 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 April 25 and the first fall freeze around October 17, a growing season of about 175 days.

Median at 36°F
last May 8, first October 5
Median at 32°F
last April 25, first October 17
Median at 28°F
last April 12, first October 30

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 20May 16May 13May 11May 8May 4May 2Apr 30Apr 26
32°FMay 8May 4Apr 30Apr 28Apr 25Apr 23Apr 21Apr 18Apr 13
28°FApr 26Apr 21Apr 18Apr 15Apr 12Apr 9Apr 7Apr 4Apr 1
24°FApr 13Apr 9Apr 6Apr 4Apr 2Apr 1Mar 30Mar 26Mar 20
20°FApr 5Apr 2Mar 31Mar 29Mar 26Mar 22Mar 19Mar 16Mar 12
16°FMar 31Mar 27Mar 24Mar 21Mar 18Mar 16Mar 13Mar 10Mar 5

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 24Sep 28Oct 1Oct 2Oct 5Oct 7Oct 10Oct 14Oct 19
32°FOct 3Oct 7Oct 11Oct 14Oct 17Oct 20Oct 23Oct 29Nov 2
28°FOct 14Oct 20Oct 24Oct 28Oct 30Nov 1Nov 5Nov 9Nov 14
24°FOct 30Nov 2Nov 5Nov 9Nov 12Nov 16Nov 19Nov 22Nov 28
20°FNov 9Nov 15Nov 18Nov 21Nov 24Nov 27Nov 30Dec 2Dec 8
16°FNov 21Nov 26Nov 29Dec 1Dec 3Dec 6Dec 9Dec 14Dec 20

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°F169162158154150146143139134
32°F195188183179175171166161155
28°F220213208205202199195190183
24°F243236232228225221216212205
20°F264258253248245241237233227
16°F281274269265262258254248242

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
6,529
Cooling degree days, base 65°F
766
Growing degree days, base 40°F
4,961
Growing degree days, base 45°F
3,856
Growing degree days, base 50°F
2,887
Growing degree days, base 55°F
2,049
Growing degree days, base 60°F
1,340

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,28500
February1,09801
March95606
April536471
May21838296
June44144551
July4275736
August11222676
September11578415
October4326119
November744016
December1,08701

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 10.5 km from Warwick. 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 USC00198573 (Tully Lake). Public domain.