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USDA Hardiness Zone 5a

Frost Dates for 80654 — Wiggins, Colorado

NOAA 1991–2020 normals from Fort Morgan, CO (4,376 ft), 12 miles east.

Updated

In Wiggins, the last spring frost (32°F) is around May 6 in half of years and has passed by May 19 in nine years out of ten. The first fall frost comes around October 6, as early as September 24 one year in ten, leaving a typical freeze-free season of 153 days (NOAA, Fort Morgan, CO).

Last spring frost
May 6

50% probability

First fall frost
October 6

50% probability

Growing season
153 days

freeze-free, 50%

Hardiness zone
5a

-20 to -15°F (-28.9 to -26.1°C) coldest night

First snow
November 16

median, 1991–2020

Last snow
April 7

median, 1991–2020

Winters with snow
100%

20 of 20 observed

Snow per year
22.7"

NOAA normal

Frost risk by date in Wiggins

Half of springs at Fort Morgan, CO see their last 32°F night by May 6; only one in ten is past it by April 23, and one in ten still has one after May 19. Planting tender crops after May 10 leaves a 30% risk of a frost on them, after May 13 20%, and after May 19 10%. The 13 days between the even-odds date and the one-in-ten date is narrower than at 67% of the 110 Colorado stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 6 in half of years, as early as September 24 one year in ten, and holds off past October 18 one year in ten. A hard freeze of 28°F follows 9 days later, around October 15; in spring the one-in-ten date for 28°F is May 9, 10 days before the 32°F one. The freeze-free season lasts 153 days in a typical year, longer than at 66% of the 110 Colorado stations; it reaches 168 days one year in ten and falls short of 135 one year in ten. On average 170 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 9 days longer, to about May 15, and return around September 28. Severe cold of 16°F or below comes every winter, usually between November 7 and March 19.

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

Freeze probabilities 1991–2020 at Fort Morgan, CO, 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 80654 →Compare Wiggins with another place →

Weather by month in Wiggins

July is the warmest month at Fort Morgan, CO, averaging 90°F by day and 60°F at night; January is the coldest at 42°F and 13°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 73% of years.

Warmth for growing adds up to 2,972 growing degree days a year (base 50°F), more than at 76% of the 110 Colorado stations. 32% of them (950) have built up by the end of June, and July adds the most, 773. Precipitation totals 14.3 inches a year, most in July (2.4") and least in January (0.3"); May to September bring 67% of it.

Monthly normals 1991–2020 at Fort Morgan, CO
MonthHigh °FLow °FPrecip. in32°F nightNights ≤ 32°FGDD 50°F
Jan42130.3100%310
Feb45150.3100%271
Mar56250.7100%2622
Apr63331.5100%1487
May72432.273%2278
Jun84542.20%0563
Jul90602.40%0773
Aug88571.70%0694
Sep81471.127%1424
Oct66341.1100%12121
Nov52210.5100%279
Dec42130.3100%310

Monthly normals 1991–2020 at Fort Morgan, CO (4,376 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, Woodrow 6NNE, CO, 28 miles east of Wiggins, has a last frost 9 days later (May 15), a first frost 5 days earlier (October 1), a season 13 days shorter.

Frost dates for 80723 (Brush) →

When it snows in Wiggins, Colorado

The first measurable snow (0.1 inch or more) in Wiggins usually arrives around November 16, and the last of the season around April 7. Those are the middle dates across the winters of 1991–2020 at Fort Morgan, CO, 11.5 miles away: half of years saw snow earlier, half later. Every one of those winters saw snow. The last 32°F night of spring typically comes 29 days after the last snow.

Planting calendar for 80654

What to do and when, from the 50% frost dates for Wiggins, Colorado
WhenWhat to do
February 25 – March 11Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out.
March 11 – March 25Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early.
April 8 – April 22Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil.
May 6 onwardTransplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast.
by July 14Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops.
by September 22Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation.
October 6 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 80654 is 12 miles from Fort Morgan, CO, which stands at 4,376 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 80701 (Fort Morgan). The 2023 USDA Plant Hardiness Zone Map lists ZIP 80654 in zone 5a, the band where the coldest night of the year averaged -20 to -15°F (-28.9 to -26.1°C) over 1991–2020; a zone describes winter lows, not frost dates.

Frost dates across Colorado →

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 5a places in Colorado