USDA Hardiness Zone 5a
Frost Dates for 55106 — Saint Paul, Minnesota
NOAA 1991–2020 normals from St Paul, MN (900 ft), 2 miles southeast.
Updated
In Saint Paul, the last spring frost (32°F) is around April 26 in half of years and has passed by May 11 in nine years out of ten. The first fall frost comes around October 12, as early as September 27 one year in ten, leaving a typical freeze-free season of 166 days (NOAA, St Paul, MN).
- Last spring frost
- April 26
- First fall frost
- October 12
- Growing season
- 166 days
- Hardiness zone
- 5a
50% probability
50% probability
freeze-free, 50%
-20 to -15°F (-28.9 to -26.1°C) coldest night
- First snow
- November 5
- Last snow
- April 11
- Winters with snow
- 100%
- Snow per year
- —
median, 1991–2020
median, 1991–2020
15 of 15 observed
NOAA normal
Frost risk by date in Saint Paul
Half of springs at St Paul, MN see their last 32°F night by April 26; only one in ten is past it by April 12, and one in ten still has one after May 11. Planting tender crops after May 1 leaves a 30% risk of a frost on them, after May 5 20%, and after May 11 10%. The 15 days between the even-odds date and the one-in-ten date is wider than at 64% of the 142 Minnesota stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 12 in half of years, as early as September 27 one year in ten, and holds off past October 25 one year in ten. A hard freeze of 28°F follows 12 days later, around October 24; in spring the one-in-ten date for 28°F is April 30, 11 days before the 32°F one. The freeze-free season lasts 166 days in a typical year, longer than at 88% of the 142 Minnesota stations; it reaches 187 days one year in ten and falls short of 148 one year in ten. On average 154 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 7, and return around October 3. Severe cold of 16°F or below comes every winter, usually between November 19 and March 22.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 23 | Apr 29 | May 1 | May 3 | May 7 | May 9 | May 12 | May 16 | May 21 |
| 32°F | Apr 12 | Apr 17 | Apr 21 | Apr 24 | Apr 26 | Apr 29 | May 1 | May 5 | May 11 |
| 28°F | Apr 2 | Apr 6 | Apr 9 | Apr 13 | Apr 16 | Apr 19 | Apr 22 | Apr 26 | Apr 30 |
| 24°F | Mar 22 | Mar 30 | Apr 2 | Apr 4 | Apr 6 | Apr 9 | Apr 11 | Apr 15 | Apr 20 |
| 20°F | Mar 14 | Mar 19 | Mar 23 | Mar 28 | Mar 31 | Apr 2 | Apr 4 | Apr 7 | Apr 12 |
| 16°F | Mar 8 | Mar 12 | Mar 16 | Mar 19 | Mar 22 | Mar 26 | Mar 30 | Apr 1 | Apr 6 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 20 | Sep 25 | Sep 28 | Oct 1 | Oct 3 | Oct 5 | Oct 8 | Oct 11 | Oct 16 |
| 32°F | Sep 27 | Oct 2 | Oct 5 | Oct 8 | Oct 12 | Oct 14 | Oct 18 | Oct 21 | Oct 25 |
| 28°F | Oct 7 | Oct 14 | Oct 17 | Oct 21 | Oct 24 | Oct 26 | Oct 30 | Nov 1 | Nov 6 |
| 24°F | Oct 19 | Oct 25 | Oct 29 | Oct 31 | Nov 2 | Nov 5 | Nov 8 | Nov 12 | Nov 17 |
| 20°F | Oct 29 | Nov 1 | Nov 5 | Nov 8 | Nov 11 | Nov 14 | Nov 17 | Nov 21 | Nov 26 |
| 16°F | Nov 4 | Nov 10 | Nov 13 | Nov 16 | Nov 19 | Nov 22 | Nov 24 | Nov 28 | Dec 3 |
Freeze probabilities 1991–2020 at St Paul, MN, 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 55106 →Compare Saint Paul with another place →
Weather by month in Saint Paul
July is the warmest month at St Paul, MN, averaging 82°F by day and 63°F at night; January is the coldest at 23°F and 8°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 32% of years.
Warmth for growing adds up to 2,708 growing degree days a year (base 50°F), more than at 82% of the 142 Minnesota stations. 33% of them (900) have built up by the end of June, and July adds the most, 697.
| Month | High °F | Low °F | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|
| Jan | 23 | 8 | 100% | 31 | 0 |
| Feb | 28 | 11 | 100% | 26 | 0 |
| Mar | 41 | 23 | 100% | 25 | 6 |
| Apr | 56 | 36 | 100% | 10 | 68 |
| May | 69 | 48 | 32% | 1 | 282 |
| Jun | 78 | 59 | 0% | 0 | 545 |
| Jul | 82 | 63 | 0% | 0 | 697 |
| Aug | 80 | 61 | 0% | 0 | 632 |
| Sep | 72 | 53 | 16% | 1 | 374 |
| Oct | 57 | 39 | 96% | 8 | 96 |
| Nov | 41 | 27 | 100% | 23 | 9 |
| Dec | 28 | 15 | 100% | 30 | 0 |
Monthly normals 1991–2020 at St Paul, MN (900 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, St Paul Downtown Airport, MN, 2 miles south of Saint Paul and 200 feet lower, has a last frost 2 days earlier (April 24), a first frost 4 days later (October 16), a season 8 days longer.
When it snows in Saint Paul, Minnesota
The first measurable snow (0.1 inch or more) in Saint Paul usually arrives around November 5, and the last of the season around April 11. Those are the middle dates across the winters of 1991–2020 at St Paul, MN, 1.8 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 15 days after the last snow.
Planting calendar for 55106
| When | What to do |
|---|---|
| February 15 – March 1 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| March 1 – March 15 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 29 – April 12 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 26 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 20 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by September 28 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 12 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 55106 is 2 miles from St Paul, MN, which stands at 900 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 5 other ZIP codes share the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 55106 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 Minnesota →
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.