Ogunquit climate

Ogunquit Frost Dates and Growing Season

NOAA 1991-2020 normals for Cape Neddick, 4.2 km from Ogunquit, elevation 152 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Cape Neddick. 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 1 and the first fall freeze around October 14, a growing season of about 165 days.

Median at 36°F
last May 14, first October 3
Median at 32°F
last May 1, first October 14
Median at 28°F
last April 18, first October 28

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

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 22Sep 26Sep 29Oct 1Oct 3Oct 5Oct 8Oct 12Oct 16
32°FOct 1Oct 5Oct 8Oct 11Oct 14Oct 17Oct 21Oct 25Oct 31
28°FOct 12Oct 17Oct 21Oct 25Oct 28Nov 1Nov 3Nov 7Nov 12
24°FOct 26Nov 1Nov 4Nov 8Nov 11Nov 13Nov 16Nov 20Nov 25
20°FNov 10Nov 15Nov 18Nov 21Nov 23Nov 26Nov 29Dec 2Dec 7
16°FNov 18Nov 23Nov 27Nov 30Dec 1Dec 4Dec 7Dec 12Dec 18

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°F159152149145142139135132127
32°F185178173169165162158153147
28°F212205200196192189184179172
24°F239232226222218214210205199
20°F261254250245241238234229222
16°F280273268263260256253248242

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
6,967
Cooling degree days, base 65°F
415
Growing degree days, base 40°F
4,250
Growing degree days, base 45°F
3,185
Growing degree days, base 50°F
2,266
Growing degree days, base 55°F
1,508
Growing degree days, base 60°F
885

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,29500
February1,10900
March99418
April613132
May32712175
June9061423
July12158610
August15137587
September15945340
October478180
November770010
December1,10500

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 4.2 km from Ogunquit. Low ground, valleys and open fields freeze earlier and later than a town center or a hillside.

More

Sources

NOAA NCEI U.S. Climate Normals, 1991-2020, annual and seasonal normals for station USC00171131 (Cape Neddick). Public domain.