Henrietta climate

Henrietta Frost Dates and Growing Season

NOAA 1991-2020 normals for Rochester Gtr Intl AP, 8.3 km from Henrietta, elevation 533 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Rochester Gtr Intl AP. 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 24 and the first fall freeze around October 25, a growing season of about 181 days.

Median at 36°F
last May 4, first October 11
Median at 32°F
last April 24, first October 25
Median at 28°F
last April 14, first November 6

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 19May 14May 10May 7May 4May 1Apr 29Apr 27Apr 23
32°FMay 8May 3Apr 30Apr 27Apr 24Apr 22Apr 19Apr 16Apr 12
28°FApr 26Apr 22Apr 19Apr 16Apr 14Apr 10Apr 7Apr 4Apr 1
24°FApr 16Apr 11Apr 7Apr 4Apr 2Apr 1Mar 29Mar 24Mar 19
20°FApr 6Apr 1Mar 31Mar 28Mar 24Mar 21Mar 18Mar 14Mar 9
16°FMar 30Mar 25Mar 21Mar 18Mar 15Mar 12Mar 9Mar 5Feb 28

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 28Oct 1Oct 4Oct 7Oct 11Oct 14Oct 17Oct 20Oct 27
32°FOct 8Oct 14Oct 18Oct 22Oct 25Oct 28Oct 31Nov 3Nov 7
28°FOct 25Oct 30Nov 1Nov 3Nov 6Nov 8Nov 11Nov 15Nov 21
24°FNov 4Nov 8Nov 12Nov 15Nov 18Nov 21Nov 25Nov 29Dec 3
20°FNov 14Nov 19Nov 22Nov 26Nov 29Dec 1Dec 4Dec 9Dec 16
16°FNov 22Nov 28Dec 1Dec 4Dec 8Dec 12Dec 16Dec 21Dec 28

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°F176170166162158154150145139
32°F201193188185181177173168162
28°F228220215211207203199194186
24°F252244238234230225221216211
20°F273264259254249245241235229
16°F292284278272268264259254247

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
6,273
Cooling degree days, base 65°F
677
Growing degree days, base 40°F
4,964
Growing degree days, base 45°F
3,827
Growing degree days, base 50°F
2,835
Growing degree days, base 55°F
1,980
Growing degree days, base 60°F
1,255

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,20302
February1,05302
March924115
April549475
May23240290
June49128530
July6234693
August12190643
September11472411
October4048143
November704029
December1,02503

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 8.3 km from Henrietta. 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 USW00014768 (Rochester Gtr Intl AP). Public domain.