Velva climate

Velva Frost Dates and Growing Season

NOAA 1991-2020 normals for Velva, 1 km from Velva, elevation 1510 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Velva. 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 22 and the first fall freeze around September 22, a growing season of about 123 days.

Median at 36°F
last May 31, first September 13
Median at 32°F
last May 22, first September 22
Median at 28°F
last May 11, first September 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°FJun 13Jun 7Jun 5Jun 2May 31May 27May 25May 22May 18
32°FJun 3May 31May 27May 24May 22May 18May 16May 13May 8
28°FMay 26May 22May 18May 14May 11May 8May 5May 2Apr 29
24°FMay 19May 13May 8May 5May 2Apr 30Apr 27Apr 23Apr 18
20°FMay 7May 2Apr 30Apr 26Apr 23Apr 19Apr 16Apr 13Apr 9
16°FApr 28Apr 22Apr 19Apr 16Apr 13Apr 10Apr 7Apr 4Apr 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°FAug 30Sep 4Sep 7Sep 10Sep 13Sep 16Sep 18Sep 20Sep 23
32°FSep 10Sep 14Sep 17Sep 20Sep 22Sep 23Sep 25Sep 28Oct 1
28°FSep 19Sep 23Sep 25Sep 28Sep 30Oct 2Oct 5Oct 8Oct 12
24°FSep 27Oct 1Oct 4Oct 6Oct 9Oct 11Oct 13Oct 17Oct 21
20°FOct 5Oct 8Oct 12Oct 15Oct 17Oct 19Oct 23Oct 26Nov 1
16°FOct 11Oct 16Oct 20Oct 23Oct 26Oct 29Nov 1Nov 3Nov 9

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°F120116112109105101979284
32°F141134130126123119116111105
28°F159153149144141138133129123
24°F178171167162159155151147139
20°F196188184180176172168163157
16°F212206201198193189185181174

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
9,597
Cooling degree days, base 65°F
271
Growing degree days, base 40°F
3,484
Growing degree days, base 45°F
2,589
Growing degree days, base 50°F
1,810
Growing degree days, base 55°F
1,154
Growing degree days, base 60°F
632

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,75400
February1,46700
March1,23401
April765023
May3938162
June13943357
July47109527
August7890479
September28320221
October712140
November1,15201
December1,57300

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 1 km from Velva. 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 USC00328990 (Velva). Public domain.