Ruch climate

Ruch Frost Dates and Growing Season

NOAA 1991-2020 normals for Ruch, 2.7 km from Ruch, elevation 1550 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Ruch. 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 4 and the first fall freeze around October 13, a growing season of about 160 days.

Median at 36°F
last May 25, first September 26
Median at 32°F
last May 4, first October 13
Median at 28°F
last April 6, first November 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°FJun 15Jun 6Jun 2May 29May 25May 21May 16May 12May 5
32°FMay 23May 16May 11May 7May 4Apr 30Apr 27Apr 22Apr 15
28°FMay 2Apr 25Apr 18Apr 12Apr 6Apr 2Mar 29Mar 21Mar 12
24°FApr 1Mar 25Mar 18Mar 10Mar 4Feb 28Feb 22Feb 13Jan 31
20°FFeb 28Feb 21Feb 11Feb 2Jan 25Jan 12Jan 3Dec 26Dec 12
16°FJan 28Jan 15Jan 5Jan 1Dec 30Dec 25Dec 18Dec 10Dec 1

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 5Sep 12Sep 17Sep 21Sep 26Oct 1Oct 4Oct 7Oct 14
32°FSep 22Sep 29Oct 4Oct 9Oct 13Oct 16Oct 21Oct 25Oct 30
28°FOct 8Oct 18Oct 23Oct 28Nov 1Nov 3Nov 8Nov 14Nov 23
24°FOct 29Nov 3Nov 9Nov 14Nov 20Nov 26Dec 1Dec 9Dec 22
20°FNov 9Nov 21Nov 29Dec 4Dec 11Dec 19Dec 28Jan 7Jan 24
16°FNov 20Dec 1Dec 5Dec 11Dec 18Dec 26Dec 31Jan 5Jan 21

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°F14914013512812211711010293
32°F187179172166160155149142132
28°F237224216209202196190182171
24°F306290277268260252242233220
20°F365352339331323314306295278
16°F365365365365365362354344330

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
88% of years
16°F or colder
41% 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
4,510
Cooling degree days, base 65°F
611
Growing degree days, base 40°F
5,434
Growing degree days, base 45°F
4,011
Growing degree days, base 50°F
2,844
Growing degree days, base 55°F
1,906
Growing degree days, base 60°F
1,166

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January76902
February61609
March569033
April425192
May22121273
June8274443
July10226682
August12200653
September8580446
October3179185
November610023
December79504

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 2.7 km from Ruch. 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 USC00357391 (Ruch). Public domain.