USDA Hardiness Zone 8b
Frost Dates for 98406 — Tacoma, Washington
NOAA 1991–2020 normals from Tacoma Narrows Airport, WA (292 ft), 4 miles west.
Updated
In Tacoma, the last spring frost (32°F) is around March 11 in half of years and has passed by April 2 in nine years out of ten. The first fall frost comes around November 21, as early as November 3 one year in ten, leaving a typical freeze-free season of 254 days (NOAA, Tacoma Narrows Airport, WA).
- Last spring frost
- March 11
- First fall frost
- November 21
- Growing season
- 254 days
- Hardiness zone
- 8b
50% probability
50% probability
freeze-free, 50%
15 to 20°F (-9.4 to -6.7°C) coldest night
- First snow
- Rare
- Last snow
- Rare
- Winters with snow
- 15%
- Snow per year
- —
median, 1991–2020
median, 1991–2020
3 of 20 observed
NOAA normal
Frost risk by date in Tacoma
Half of springs at Tacoma Narrows Airport, WA see their last 32°F night by March 11; only one in ten is past it by February 15, and one in ten still has one after April 2. Planting tender crops after March 21 leaves a 30% risk of a frost on them, after March 27 20%, and after April 2 10%. The 22 days between the even-odds date and the one-in-ten date is wider than at 71% of the 113 Washington stations behind this site's ZIP pages, so a fixed calendar date is a gamble here.
In fall the first 32°F night comes by November 21 in half of years, as early as November 3 one year in ten, and holds off past December 10 one year in ten. A hard freeze of 28°F follows 20 days later, around December 11; in spring the one-in-ten date for 28°F is March 8, 25 days before the 32°F one. The freeze-free season lasts 254 days in a typical year, longer than at 96% of the 113 Washington stations; it reaches 286 days one year in ten and falls short of 226 one year in ten. On average 21 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 31 days longer, to about April 11, and return around November 4. Nights of 24°F, cold enough to damage hardier plants, come in 62% of winters and 16°F in 1%.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Mar 26 | Apr 1 | Apr 4 | Apr 8 | Apr 11 | Apr 15 | Apr 20 | Apr 25 | May 2 |
| 32°F | Feb 15 | Feb 23 | Mar 1 | Mar 5 | Mar 11 | Mar 16 | Mar 21 | Mar 27 | Apr 2 |
| 28°F97% of yrs | Jan 1 | Jan 13 | Jan 29 | Feb 6 | Feb 13 | Feb 18 | Feb 23 | Feb 28 | Mar 8 |
| 24°F62% of yrs | Dec 2 | Dec 10 | Dec 21 | Jan 2 | Jan 11 | Jan 22 | Feb 1 | Feb 10 | Feb 19 |
| 20°F18% of yrs | too rare for a date | ||||||||
| 16°F1% of yrs | too rare for a date | ||||||||
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 21 | Oct 26 | Oct 29 | Oct 31 | Nov 4 | Nov 7 | Nov 10 | Nov 14 | Nov 19 |
| 32°F | Nov 3 | Nov 9 | Nov 13 | Nov 16 | Nov 21 | Nov 24 | Nov 28 | Dec 2 | Dec 10 |
| 28°F97% of yrs | Nov 18 | Nov 25 | Dec 1 | Dec 5 | Dec 11 | Dec 17 | Dec 26 | Jan 1 | Jan 19 |
| 24°F62% of yrs | Nov 26 | Dec 1 | Dec 6 | Dec 12 | Dec 19 | Dec 29 | Jan 5 | Jan 20 | Feb 5 |
| 20°F18% of yrs | too rare for a date | ||||||||
| 16°F1% of yrs | too rare for a date | ||||||||
Freeze probabilities 1991–2020 at Tacoma Narrows Airport, WA, 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 98406 →Compare Tacoma with another place →
Weather by month in Tacoma
August is the warmest month at Tacoma Narrows Airport, WA, averaging 76°F by day and 54°F at night; December is the coldest at 46°F and 36°F. A freezing night is all but certain in every month from December to February (a 90% chance or more). From May to October the chance of a 32°F night stays under 10% each month. In spring, March still brings one in 66% of years and April still brings one in 13% of years.
Warmth for growing adds up to 1,896 growing degree days a year (base 50°F), fewer than at 58% of the 113 Washington stations. 29% of them (549) have built up by the end of June, and August adds the most, 463. Precipitation totals 42.1 inches a year, most in November (7.2") and least in July (0.7"); May to September bring 16% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 46 | 36 | 6.1 | 96% | 6 | 2 |
| Feb | 48 | 37 | 4.1 | 93% | 5 | 2 |
| Mar | 53 | 39 | 4.6 | 66% | 2 | 14 |
| Apr | 58 | 41 | 3.4 | 13% | <1 | 46 |
| May | 65 | 47 | 2.1 | 0% | 0 | 179 |
| Jun | 70 | 51 | 1.4 | 0% | 0 | 306 |
| Jul | 76 | 54 | 0.7 | 0% | 0 | 457 |
| Aug | 76 | 54 | 0.9 | 0% | 0 | 463 |
| Sep | 70 | 51 | 1.5 | 0% | 0 | 315 |
| Oct | 59 | 46 | 4.3 | 7% | 0 | 96 |
| Nov | 51 | 40 | 7.2 | 74% | 3 | 13 |
| Dec | 46 | 36 | 5.8 | 96% | 6 | 2 |
Monthly normals 1991–2020 at Tacoma Narrows Airport, WA (292 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, Tacoma #1, WA, 4 miles east of Tacoma and 267 feet lower, has a last frost 3 days earlier (March 8), a first frost 7 days earlier (November 14), a season 4 days shorter.
When it snows in Tacoma, Washington
Measurable snow is rare here: only 3 of 20 winters from 1991 to 2020 recorded 0.1 inch or more at Tacoma #1, WA, 4 miles away, so there is no typical first-snow date to plan around.
Planting calendar for 98406
| When | What to do |
|---|---|
| December 31 – January 14 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| January 14 – January 28 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| February 11 – February 25 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| March 11 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by August 29 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by November 7 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| November 21 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 98406 is 4 miles from Tacoma Narrows Airport, WA, which stands at 292 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 14 other ZIP codes share the station; its figures are presented in full for 98466 (University Place). The 2023 USDA Plant Hardiness Zone Map lists ZIP 98406 in zone 8b, the band where the coldest night of the year averaged 15 to 20°F (-9.4 to -6.7°C) over 1991–2020; a zone describes winter lows, not frost dates.
Frost dates across Washington →
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.