Magazine climate

Magazine Frost Dates and Growing Season

NOAA 1991-2020 normals for Blue Mtn Dam, 14.7 km from Magazine, elevation 426 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Blue Mtn Dam. 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 March 31 and the first fall freeze around November 1, a growing season of about 215 days.

Median at 36°F
last April 12, first October 23
Median at 32°F
last March 31, first November 1
Median at 28°F
last March 17, first November 12

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°FApr 30Apr 24Apr 19Apr 16Apr 12Apr 9Apr 6Apr 2Mar 29
32°FApr 17Apr 11Apr 7Apr 3Mar 31Mar 28Mar 23Mar 18Mar 12
28°FApr 4Mar 31Mar 25Mar 21Mar 17Mar 13Mar 9Mar 4Feb 28
24°FMar 22Mar 16Mar 12Mar 8Mar 5Mar 1Feb 27Feb 21Feb 13
20°FMar 14Mar 6Mar 2Feb 27Feb 21Feb 15Feb 10Feb 2Jan 27
16°FMar 4Feb 27Feb 17Feb 11Feb 3Jan 31Jan 26Jan 18Jan 7

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°FOct 9Oct 15Oct 18Oct 21Oct 23Oct 26Oct 28Oct 31Nov 4
32°FOct 18Oct 23Oct 27Oct 30Nov 1Nov 3Nov 6Nov 11Nov 17
28°FOct 28Nov 1Nov 5Nov 8Nov 12Nov 16Nov 20Nov 24Dec 1
24°FNov 7Nov 13Nov 18Nov 22Nov 26Dec 1Dec 3Dec 9Dec 17
20°FNov 19Nov 26Dec 1Dec 5Dec 11Dec 17Dec 23Dec 31Jan 7
16°FDec 2Dec 11Dec 18Dec 25Dec 29Jan 3Jan 7Jan 12Jan 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°F212206200196192188183178172
32°F238231225220215210205200193
28°F265256248243238233228222214
24°F292282275270264259252246237
20°F327318309302295288281273261
16°F358347339333327320312303291

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
94% 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
3,448
Cooling degree days, base 65°F
1,851
Growing degree days, base 40°F
7,862
Growing degree days, base 45°F
6,357
Growing degree days, base 50°F
5,003
Growing degree days, base 55°F
3,804
Growing degree days, base 60°F
2,753

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January806120
February607139
March4379140
April18543324
May44155577
June1355804
July0495959
August0473938
September17251684
October16662373
November4526116
December732129

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 14.7 km from Magazine. 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 USC00030798 (Blue Mtn Dam). Public domain.