Pasco County climate

Pasco County Frost Dates and Growing Season

NOAA 1991-2020 normals for Saint Leo, 17.9 km from Pasco County, elevation 190 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Saint Leo. 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 January 31 and the first fall freeze around January 8, a growing season of about 336 days.

Median at 36°F
last February 16, first December 22
Median at 32°F
last January 31, first January 8
Median at 28°F
last January 24, first January 14

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°FMar 15Mar 6Feb 28Feb 22Feb 16Feb 9Feb 3Jan 27Jan 16
32°FFeb 28Feb 19Feb 12Feb 5Jan 31Jan 26Jan 18Jan 10Jan 3
28°FFeb 19Feb 9Feb 3Jan 31Jan 24Jan 15Jan 10Jan 3Dec 27
24°FFeb 7Feb 3Feb 1Jan 27Jan 22Jan 13Jan 8Jan 4Dec 29
20°F–––––––––
16°F–––––––––

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°FNov 28Dec 3Dec 7Dec 14Dec 22Dec 30Jan 5Jan 12Jan 23
32°FDec 10Dec 21Dec 29Jan 3Jan 8Jan 13Jan 20Jan 28Feb 10
28°FDec 21Dec 29Jan 3Jan 9Jan 14Jan 23Jan 30Feb 5Feb 15
24°FDec 26Jan 4Jan 7Jan 12Jan 21Jan 26Jan 31Feb 2Feb 7
20°F–––––––––
16°F–––––––––

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°F340329321312306300293284274
32°F365363353343336329322312302
28°F365365365365365360349338326
24°F365365365365365365365365363
20°F365365365365365365365365365
16°F365365365365365365365365365

How often it gets that cold

The share of years with at least one night at or below each temperature.

36°F or colder
98% of years
32°F or colder
81% of years
28°F or colder
37% of years
24°F or colder
10% of years
20°F or colder
0% of years
16°F or colder
0% 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
619
Cooling degree days, base 65°F
3,149
Growing degree days, base 40°F
11,656
Growing degree days, base 45°F
9,841
Growing degree days, base 50°F
8,044
Growing degree days, base 55°F
6,298
Growing degree days, base 60°F
4,650

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January20238320
February12356360
March66110511
April12205644
May1363828
June0456906
July0507972
August0508973
September0442893
October8291749
November59113505
December15060386

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 17.9 km from Pasco County. 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 USC00087851 (Saint Leo). Public domain.