USDA Hardiness Zone 5b
Frost Dates for 50063 — Dallas Center, Iowa
NOAA 1991–2020 normals from Des Moines Wsfo-Johnston, IA (959 ft), 12 miles east.
Updated
In Dallas Center, the last spring frost (32°F) is around April 19 in half of years and has passed by May 3 in nine years out of ten. The first fall frost comes around October 18, as early as October 1 one year in ten, leaving a typical freeze-free season of 179 days (NOAA, Des Moines Wsfo-Johnston, IA).
- Last spring frost
- April 19
- First fall frost
- October 18
- Growing season
- 179 days
- Hardiness zone
- 5b
50% probability
50% probability
freeze-free, 50%
-15 to -10°F (-26.1 to -23.3°C) coldest night
- First snow
- November 15
- Last snow
- March 29
- Winters with snow
- 100%
- Snow per year
- 38"
median, 1991–2020
median, 1991–2020
25 of 25 observed
NOAA normal
Frost risk by date in Dallas Center
Half of springs at Des Moines Wsfo-Johnston, IA see their last 32°F night by April 19; only one in ten is past it by April 5, and one in ten still has one after May 3. Planting tender crops after April 25 leaves a 30% risk of a frost on them, after April 29 20%, and after May 3 10%. The 14 days between the even-odds date and the one-in-ten date is wider than at 58% of the 132 Iowa stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 18 in half of years, as early as October 1 one year in ten, and holds off past October 30 one year in ten. A hard freeze of 28°F follows 9 days later, around October 27; in spring the one-in-ten date for 28°F is April 23, 10 days before the 32°F one. The freeze-free season lasts 179 days in a typical year, longer than at 86% of the 132 Iowa stations; it reaches 198 days one year in ten and falls short of 159 one year in ten. On average 135 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 April 30, and return around October 7. Severe cold of 16°F or below comes every winter, usually between November 21 and March 13.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 15 | Apr 20 | Apr 23 | Apr 27 | Apr 30 | May 2 | May 5 | May 7 | May 13 |
| 32°F | Apr 5 | Apr 9 | Apr 13 | Apr 16 | Apr 19 | Apr 22 | Apr 25 | Apr 29 | May 3 |
| 28°F | Mar 25 | Apr 1 | Apr 3 | Apr 6 | Apr 9 | Apr 12 | Apr 15 | Apr 19 | Apr 23 |
| 24°F | Mar 13 | Mar 19 | Mar 25 | Mar 29 | Apr 1 | Apr 3 | Apr 7 | Apr 10 | Apr 16 |
| 20°F | Mar 5 | Mar 10 | Mar 14 | Mar 18 | Mar 21 | Mar 25 | Mar 29 | Apr 2 | Apr 7 |
| 16°F | Feb 25 | Mar 2 | Mar 6 | Mar 10 | Mar 13 | Mar 16 | Mar 19 | Mar 24 | Mar 30 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 23 | Sep 28 | Sep 30 | Oct 3 | Oct 7 | Oct 9 | Oct 13 | Oct 16 | Oct 21 |
| 32°F | Oct 1 | Oct 7 | Oct 12 | Oct 15 | Oct 18 | Oct 20 | Oct 23 | Oct 26 | Oct 30 |
| 28°F | Oct 14 | Oct 19 | Oct 22 | Oct 25 | Oct 27 | Oct 30 | Nov 1 | Nov 3 | Nov 9 |
| 24°F | Oct 21 | Oct 27 | Oct 30 | Nov 1 | Nov 4 | Nov 6 | Nov 9 | Nov 13 | Nov 19 |
| 20°F | Oct 30 | Nov 3 | Nov 6 | Nov 9 | Nov 12 | Nov 15 | Nov 19 | Nov 24 | Dec 1 |
| 16°F | Nov 6 | Nov 10 | Nov 14 | Nov 17 | Nov 21 | Nov 25 | Nov 30 | Dec 3 | Dec 11 |
Freeze probabilities 1991–2020 at Des Moines Wsfo-Johnston, IA, 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 50063 →Compare Dallas Center with another place →
Weather by month in Dallas Center
July is the warmest month at Des Moines Wsfo-Johnston, IA, averaging 85°F by day and 66°F at night; January is the coldest at 30°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 September the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 15% of years.
Warmth for growing adds up to 3,361 growing degree days a year (base 50°F), more than at 89% of the 132 Iowa stations. 35% of them (1,189) have built up by the end of June, and July adds the most, 780. Precipitation totals 36.4 inches a year, most in June (5.4") and least in January (1.0"); May to September bring 60% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 30 | 13 | 1.0 | 100% | 30 | 0 |
| Feb | 35 | 17 | 1.3 | 100% | 25 | 3 |
| Mar | 49 | 29 | 2.2 | 100% | 21 | 35 |
| Apr | 62 | 40 | 4.0 | 96% | 7 | 134 |
| May | 72 | 52 | 4.8 | 15% | <1 | 374 |
| Jun | 81 | 62 | 5.4 | 0% | 0 | 643 |
| Jul | 85 | 66 | 4.3 | 0% | 0 | 780 |
| Aug | 83 | 64 | 4.0 | 0% | 0 | 721 |
| Sep | 76 | 55 | 3.4 | 9% | <1 | 472 |
| Oct | 63 | 43 | 2.5 | 90% | 5 | 172 |
| Nov | 48 | 30 | 2.0 | 100% | 18 | 27 |
| Dec | 35 | 19 | 1.5 | 100% | 28 | 1 |
Monthly normals 1991–2020 at Des Moines Wsfo-Johnston, IA (959 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, Perry, IA, 13 miles northwest of Dallas Center, has a last frost 6 days later (April 25), a first frost 8 days earlier (October 10), a season 13 days shorter.
When it snows in Dallas Center, Iowa
The first measurable snow (0.1 inch or more) in Dallas Center usually arrives around November 15, and the last of the season around March 29. Those are the middle dates across the winters of 1991–2020 at Des Moines Wsfo-Johnston, IA, 12.1 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 21 days after the last snow.
Planting calendar for 50063
| When | What to do |
|---|---|
| February 8 – February 22 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 22 – March 8 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 22 – April 5 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 19 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 26 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 4 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 18 onward | Plant 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 50063 is 12 miles from Des Moines Wsfo-Johnston, IA, which stands at 959 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 6 other ZIP codes share the station; its figures are presented in full for 50322 (Urbandale). The 2023 USDA Plant Hardiness Zone Map lists ZIP 50063 in zone 5b, the band where the coldest night of the year averaged -15 to -10°F (-26.1 to -23.3°C) over 1991–2020; a zone describes winter lows, not frost dates.
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.