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USDA Hardiness Zone 7a

Frost Dates for 83628 — Homedale, Idaho

NOAA 1991–2020 normals from Homedale 1 SE, ID (2,230 ft), 2 miles east.

Updated

In Homedale, the last spring frost (32°F) is around April 24 in half of years and has passed by May 5 in nine years out of ten. The first fall frost comes around October 9, as early as September 26 one year in ten, leaving a typical freeze-free season of 169 days (NOAA, Homedale 1 SE, ID).

Last spring frost
April 24

50% probability

First fall frost
October 9

50% probability

Growing season
169 days

freeze-free, 50%

Hardiness zone
7a

0 to 5°F (-17.8 to -15.0°C) coldest night

First snow
December 18

median, 1991–2020

Last snow
January 28

median, 1991–2020

Winters with snow
81%

21 of 26 observed

Snow per year
—

NOAA normal

Frost risk by date in Homedale

Half of springs at Homedale 1 SE, ID see their last 32°F night by April 24; only one in ten is past it by April 9, and one in ten still has one after May 5. Planting tender crops after April 29 leaves a 30% risk of a frost on them, after May 1 20%, and after May 5 10%. The 11 days between the even-odds date and the one-in-ten date is the narrowest of the 67 Idaho stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 9 in half of years, as early as September 26 one year in ten, and holds off past October 23 one year in ten. A hard freeze of 28°F follows 13 days later, around October 22; in spring the one-in-ten date for 28°F is April 25, 10 days before the 32°F one. The freeze-free season lasts 169 days in a typical year, longer than at 82% of the 67 Idaho stations; it reaches 187 days one year in ten and falls short of 150 one year in ten. On average 161 nights a year drop to 32°F or below. Nights of 36°F, when frost can still settle on leaves in low, open spots, continue 11 days longer, to about May 5, and return around September 28. Severe cold of 16°F or below comes every winter, usually between November 28 and February 8.

Spring: the chance of another night this cold after the date
Low90%80%70%60%50%40%30%20%10%
36°FApr 22Apr 28Apr 30May 2May 5May 7May 11May 15May 24
32°FApr 9Apr 14Apr 18Apr 21Apr 24Apr 26Apr 29May 1May 5
28°FMar 25Mar 31Apr 3Apr 6Apr 10Apr 13Apr 17Apr 20Apr 25
24°FMar 1Mar 9Mar 15Mar 19Mar 26Mar 31Apr 3Apr 7Apr 13
20°FFeb 10Feb 17Feb 23Feb 26Mar 1Mar 6Mar 11Mar 18Mar 30
16°FJan 7Jan 18Jan 30Feb 4Feb 8Feb 14Feb 19Feb 25Mar 4
Fall: the chance the first night this cold has come by the date
Low10%20%30%40%50%60%70%80%90%
36°FSep 16Sep 20Sep 24Sep 26Sep 28Oct 1Oct 3Oct 6Oct 11
32°FSep 26Sep 30Oct 3Oct 6Oct 9Oct 12Oct 15Oct 18Oct 23
28°FOct 8Oct 12Oct 16Oct 18Oct 22Oct 24Oct 28Nov 1Nov 4
24°FOct 18Oct 24Oct 27Oct 30Nov 1Nov 4Nov 7Nov 12Nov 19
20°FOct 29Nov 1Nov 6Nov 10Nov 14Nov 19Nov 23Nov 28Dec 2
16°FNov 5Nov 12Nov 19Nov 23Nov 28Dec 1Dec 5Dec 12Dec 24

Freeze probabilities 1991–2020 at Homedale 1 SE, ID, from NOAA NCEI U.S. Climate Normals. Where a temperature is reached in fewer than 99.5% of years, the dates describe only the years that reach it. Not a forecast.

Frost risk on any date in 83628 →Compare Homedale with another place →

Weather by month in Homedale

July is the warmest month at Homedale 1 SE, ID, averaging 92°F by day and 59°F at night; January is the coldest at 38°F and 23°F. A freezing night is all but certain in every month from October to April (a 90% chance or more). From June to August the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 23% of years.

Warmth for growing adds up to 2,961 growing degree days a year (base 50°F), more than at 87% of the 67 Idaho stations. 32% of them (937) have built up by the end of June, and July adds the most, 797. Precipitation totals 10.2 inches a year, most in January (1.5") and least in August (0.2"); May to September bring 29% of it.

Monthly normals 1991–2020 at Homedale 1 SE, ID
MonthHigh °FLow °FPrecip. in32°F nightNights ≤ 32°FGDD 50°F
Jan38231.5100%290
Feb46270.9100%251
Mar57320.9100%2219
Apr64370.997%1289
May73471.323%2316
Jun81530.80%0512
Jul92590.30%0797
Aug91550.20%0721
Sep81460.421%2399
Oct66360.898%16101
Nov50291.0100%246
Dec39231.2100%281

Monthly normals 1991–2020 at Homedale 1 SE, ID (2,230 ft), NOAA NCEI. "32°F night": chance of at least one in the month. GDD: growing degree days, base 50°F.

Compared with the next station

The nearest other station, Deer Flat Dam, ID, 10 miles east of Homedale and 280 feet higher, has a last frost 1 day earlier (April 23), a first frost 9 days later (October 18), a season 9 days longer.

Frost dates for 83607 (Caldwell) →

When it snows in Homedale, Idaho

The first measurable snow (0.1 inch or more) in Homedale usually arrives around December 18, and the last of the season around January 28. Those are the middle dates across the winters of 1991–2020 at Homedale 1 SE, ID, 1.5 miles away: half of years saw snow earlier, half later. Snow fell in 81% of those winters. The last 32°F night of spring typically comes 86 days after the last snow.

Planting calendar for 83628

What to do and when, from the 50% frost dates for Homedale, Idaho
WhenWhat to do
February 13 – February 27Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out.
February 27 – March 13Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early.
March 27 – April 10Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil.
April 24 onwardTransplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast.
by July 17Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops.
by September 25Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation.
October 9 onwardPlant garlic, mulch beds, lift tender bulbsGarlic wants a cold spell; bare soil loses structure over winter.

The weeks before and after the 50% dates are general rules of thumb, not NOAA figures; a seed packet gives the timing for each variety.

Where these figures come from

ZIP 83628 is 2 miles from Homedale 1 SE, ID, which stands at 2,230 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 1 other ZIP code shares the station; its figures are presented in full for 83676 (Wilder). The 2023 USDA Plant Hardiness Zone Map lists ZIP 83628 in zone 7a, the band where the coldest night of the year averaged 0 to 5°F (-17.8 to -15.0°C) over 1991–2020; a zone describes winter lows, not frost dates.

Frost dates across Idaho →

Hardiness zone and temperature range: USDA Plant Hardiness Zone Map 2023 (USDA-ARS, Oregon State University), ZIP-code listing, unchanged. °C converted from °F by this site.

Thirty-year averages, not a forecast: check the forecast before planting out. How stations are matched and which pages are offered to search engines: methodology.

ZIP codes measured at the same station

Other zone 7a places in Idaho