Climate and average weather in Oak Harbor
In Oak Harbor, the summers are mild, fairly dry, and mostly clear and the winters are cold, snowy, and mostly cloudy.
Over the course of the year, the temperature in Oak Harbor typically varies from 42°F to 62°F, and is rarely below 35°F or above 67°F. August is the hottest month of the year, while January is the coldest.
Based on the travel score, the best time of year to visit Oak Harbor for warm-weather activities is from early July to mid September.
- Hottest
- Aug
- 62°
- Coldest
- Jan
- 42°
- Wettest
- Nov
- 7.2 in
- Driest
- Jul
- 1.2 in
- Rain / yr
- 46.5 in
- 155 wet days
- Daylight
- 8.1–15.9 h
- shortest–longest
- Elevation
- 95 ft
- 48.3°N
- Clearest
- Jul
- 40% cloud
Oak Harbor is city on Whidbey Island in Island County, Washington State, United States.
- Density
- 925/km²
- people per km²
- Founded
- 1915
Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.
Oak Harbor weather by month, at a glance
The whole year in one picture — sky, rain, humidity, temperature and travel score. Click any band to jump to its full chart.
Each stripe is one measure across the whole year, stacked so a single day reads top to bottom. The sky band runs overcast grey on top down to clear blue at the base — more blue means sunnier — followed by the rainfall curve, the humidity band, a temperature strip that tints each stretch of the year by how warm its average high is, and the travel-score line at the foot. Scan straight down any date to read that day across every measure at once; the score climbs highest around early July to mid September.
Temperature through the year
Daily average highs and lows in Oak Harbor, from 1991–2020 of climate data. The shaded bands show the range most days fall in — 10th to 90th percentile.
The hot season lasts 3.2 months, from June 20 to September 23, with daily high temperatures above 58°F. The hottest month of the year in Oak Harbor is August, with an average high of 62°F and low of 57°F.
The cool season lasts 4.0 months, from November 19 to March 19, with daily high temperatures below 48°F. The coldest month of the year in Oak Harbor is January, with an average low of 42°F and high of 45°F.
Days typically run about 4°F warmer than nights year-round.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°F) | 45 | 46 | 48 | 51 | 55 | 58 | 62 | 62 | 59 | 54 | 49 | 45 |
| Avg low (°F) | 42 | 42 | 44 | 46 | 50 | 53 | 56 | 57 | 55 | 50 | 45 | 42 |
| Avg high (°F) | Avg low (°F) | |
|---|---|---|
| Jan | 45 | 42 |
| Feb | 46 | 42 |
| Mar | 48 | 44 |
| Apr | 51 | 46 |
| May | 55 | 50 |
| Jun | 58 | 53 |
| Jul | 62 | 56 |
| Aug | 62 | 57 |
| Sep | 59 | 55 |
| Oct | 54 | 50 |
| Nov | 49 | 45 |
| Dec | 45 | 42 |
Average hourly temperature in Oak Harbor
A compact picture of the whole year, hour by hour: each column is a day, each row an hour, and the color is the modeled average temperature. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.
Read left to right for the day of the year and top to bottom for the hour of the day; the color is the modeled temperature, cool blues through to hot reds on the same scale as the other charts. A vertical slice is a single day's swing — coolest just before dawn, warmest in the mid-afternoon — while a horizontal slice follows one hour across the seasons. The darker overlay marks night and the lighter one the twilight around sunrise and sunset. Colors run warmest on August afternoons, near 62°F, and coldest before dawn in January, near 42°F.
Oak Harbor weather by month
Every month at a glance. Click a month for its detailed page.
| Month | High / Low (°F) | Rainfall (inches) | Wet days | Snow days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|---|
| Jan | 45° / 42° | 6.2 | 18.6 | 1.4 | 8.6 | 0.9 |
| Feb | 46° / 42° | 4.2 | 14.7 | 1.3 | 9.9 | 1.1 |
| Mar | 48° / 44° | 4.8 | 17.9 | 0.3 | 11.6 | 1.5 |
| Apr | 51° / 46° | 3.3 | 14 | 0 | 13.4 | 2.3 |
| May | 55° / 50° | 2.6 | 10.5 | 0 | 14.9 | 3.5 |
| Jun | 58° / 53° | 2.1 | 9.4 | 0 | 15.8 | 4.4 |
| Jul | 62° / 56° | 1.2 | 5.8 | 0 | 15.5 | 6.0 |
| Aug | 62° / 57° | 1.4 | 5.3 | 0 | 14.1 | 6.3 |
| Sep | 59° / 55° | 2.3 | 8.7 | 0 | 12.4 | 5.0 |
| Oct | 54° / 50° | 4.7 | 13.8 | 0 | 10.6 | 3.1 |
| Nov | 49° / 45° | 7.2 | 18.5 | 0.3 | 9 | 1.6 |
| Dec | 45° / 42° | 6.4 | 18.1 | 1.4 | 8.2 | 0.9 |
Chance of rain
How likely it is to rain on a typical day, and how that shifts across the wetter and drier seasons.
Oak Harbor gets about 46.5 in of precipitation a year. On a typical day the chance of rain is often wet, but that rises and falls sharply with the seasons.
The wetter season lasts 6.4 months, from around Oct 13 to Apr 24, peaking in November at about 64% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Aug 2.
November is the wettest month by volume, with 7.2 in over about 19 wet days; July is the driest, with 1.2 in. Some of the cold-season precipitation falls as snow.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rain on a day (%) | 59 | 54 | 57 | 46 | 35 | 31 | 19 | 17 | 30 | 44 | 60 | 60 |
| Rain days | 19 | 15 | 18 | 14 | 11 | 9 | 6 | 5 | 9 | 14 | 19 | 18 |
| Rain on a day (%) | Rain days | |
|---|---|---|
| Jan | 59 | 19 |
| Feb | 54 | 15 |
| Mar | 57 | 18 |
| Apr | 46 | 14 |
| May | 35 | 11 |
| Jun | 31 | 9 |
| Jul | 19 | 6 |
| Aug | 17 | 5 |
| Sep | 30 | 9 |
| Oct | 44 | 14 |
| Nov | 60 | 19 |
| Dec | 60 | 18 |
Monthly rainfall
Over a full year, Oak Harbor collects about 46.5 in of rain across 155 wet days — roughly 3.9 in in an average month.
It doesn’t fall evenly. November is the wettest month with 7.2 in, while July is the driest at just 1.2 in. The three wettest months alone bring about 43% of the year’s total, and some of the cold-season precipitation falls as snow.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rainfall (in) | 6.2 | 4.2 | 4.8 | 3.3 | 2.6 | 2.1 | 1.2 | 1.4 | 2.3 | 4.7 | 7.2 | 6.4 |
| Rain days | 19 | 15 | 18 | 14 | 11 | 9 | 6 | 5 | 9 | 14 | 19 | 18 |
| Snow days | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 |
| Rainfall (in) | Rain days | Snow days | |
|---|---|---|---|
| Jan | 6.2 | 19 | 1 |
| Feb | 4.2 | 15 | 1 |
| Mar | 4.8 | 18 | 0 |
| Apr | 3.3 | 14 | 0 |
| May | 2.6 | 11 | 0 |
| Jun | 2.1 | 9 | 0 |
| Jul | 1.2 | 6 | 0 |
| Aug | 1.4 | 5 | 0 |
| Sep | 2.3 | 9 | 0 |
| Oct | 4.7 | 14 | 0 |
| Nov | 7.2 | 19 | 0 |
| Dec | 6.4 | 18 | 1 |
Snow in Oak Harbor
Average snowy days through the year, the snow-season span, and estimated snowfall — for ski trips and the perennial 'will there be snow at Christmas?' question.
Oak Harbor averages about 5 snowy days a year. Snow season runs roughly Nov 22 to Mar 12 — about 3.6 months.
December is snowiest, with roughly 1.3 day of snow and an estimated 2 in of snowfall. Over the year that adds up to an estimated 7 in of snow.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Snow days | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 |
| Snowfall (in) | 2 | 2 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 2 |
| Snow days | Snowfall (in) | |
|---|---|---|
| Jan | 1 | 2 |
| Feb | 1 | 2 |
| Mar | 0 | 1 |
| Apr | 0 | 0 |
| May | 0 | 0 |
| Jun | 0 | 0 |
| Jul | 0 | 0 |
| Aug | 0 | 0 |
| Sep | 0 | 0 |
| Oct | 0 | 0 |
| Nov | 0 | 1 |
| Dec | 1 | 2 |
Clouds and sunshine
How often the daytime sky is clear, partly cloudy or overcast.
In Oak Harbor, the average share of the sky covered by clouds shows significant seasonal variation over the course of the year.
The clearer part of the year begins around June 8 and lasts for 4.2 months, ending around October 12. The clearest month is August, when the sky is clear, mostly clear, or partly cloudy 67% of the time on average.
The cloudier part of the year begins around October 13 and lasts for 6.4 months, ending around April 26. The cloudiest month is December, when it is overcast or mostly cloudy 77% of the time.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Clearer (%) | 24 | 32 | 32 | 37 | 43 | 48 | 67 | 67 | 60 | 41 | 30 | 23 |
| Cloudier (%) | 76 | 68 | 68 | 63 | 57 | 52 | 33 | 33 | 40 | 59 | 70 | 77 |
| Clearer (%) | Cloudier (%) | |
|---|---|---|
| Jan | 24 | 76 |
| Feb | 32 | 68 |
| Mar | 32 | 68 |
| Apr | 37 | 63 |
| May | 43 | 57 |
| Jun | 48 | 52 |
| Jul | 67 | 33 |
| Aug | 67 | 33 |
| Sep | 60 | 40 |
| Oct | 41 | 59 |
| Nov | 30 | 70 |
| Dec | 23 | 77 |
Daylight, sunrise and sunset
Hours of daylight through the year, with sunrise and sunset times.
The gold band is daylight — sunrise runs along its lower edge, sunset along the upper — so it widens toward summer and pinches toward winter, with night the dark area above and below. The longest day, around June 16, brings about 15 h 54 min of light; the shortest, around December 16, only 8 h 06 min — a swing of roughly 7 h 48 min.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight (h) | 8.6 | 9.9 | 11.6 | 13.4 | 14.9 | 15.8 | 15.5 | 14.1 | 12.4 | 10.6 | 9.0 | 8.2 |
| Sunrise (AM) | 8:04 | 7:29 | 6:33 | 5:28 | 4:37 | 4:15 | 4:31 | 5:10 | 5:54 | 6:39 | 7:27 | 8:02 |
| Sunset (PM) | 4:36 | 5:22 | 6:07 | 6:53 | 7:36 | 8:06 | 8:01 | 7:19 | 6:15 | 5:12 | 4:24 | 4:11 |
| Daylight (h) | Sunrise (AM) | Sunset (PM) | |
|---|---|---|---|
| Jan | 8.6 | 8:04 | 4:36 |
| Feb | 9.9 | 7:29 | 5:22 |
| Mar | 11.6 | 6:33 | 6:07 |
| Apr | 13.4 | 5:28 | 6:53 |
| May | 14.9 | 4:37 | 7:36 |
| Jun | 15.8 | 4:15 | 8:06 |
| Jul | 15.5 | 4:31 | 8:01 |
| Aug | 14.1 | 5:10 | 7:19 |
| Sep | 12.4 | 5:54 | 6:15 |
| Oct | 10.6 | 6:39 | 5:12 |
| Nov | 9.0 | 7:27 | 4:24 |
| Dec | 8.2 | 8:02 | 4:11 |
Sunny days
How many genuinely sunny days each month brings — days the sky stays clear or mostly clear — banded into plain-language zones.
Oak Harbor averages about 9 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 3 and 18 days.
The sunnier stretch runs 4.0 months, from around Jun 13 to Oct 11. The sunniest month is July, with roughly 16 sunny days (bright).
The greyest month is December, down near 4 sunny days — about 77% fewer than the July peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sunny days | 4 | 5 | 6 | 7 | 9 | 9 | 16 | 16 | 14 | 9 | 5 | 4 |
| Sky | Gloomy | Gloomy | Gloomy | Gloomy | Mixed | Mixed | Bright | Bright | Mixed | Mixed | Gloomy | Gloomy |
| Sunny days | Sky | |
|---|---|---|
| Jan | 4 | Gloomy |
| Feb | 5 | Gloomy |
| Mar | 6 | Gloomy |
| Apr | 7 | Gloomy |
| May | 9 | Mixed |
| Jun | 9 | Mixed |
| Jul | 16 | Bright |
| Aug | 16 | Bright |
| Sep | 14 | Mixed |
| Oct | 9 | Mixed |
| Nov | 5 | Gloomy |
| Dec | 4 | Gloomy |
Humidity comfort
Share of days at each humidity comfort level, based on the dew point — the measure that tracks how muggy it actually feels.
Humidity comfort is graded by the dew point — the temperature at which the air would be fully saturated — because it tracks how muggy it actually feels far better than relative humidity does. A low dew point feels dry and crisp; a high one feels sticky and oppressive no matter the reading on a humidity gauge.
In Oak Harbor, the air stays dry or comfortable essentially all year. Even in September, the muggiest month, it feels humid or worse only about 0% of the time — humidity is not something you need to plan around here.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Dry (%) | 100 | 100 | 100 | 100 | 100 | 99 | 89 | 80 | 92 | 100 | 100 | 100 |
| Comfortable (%) | 0 | 0 | 0 | 0 | 0 | 1 | 11 | 20 | 8 | 0 | 0 | 0 |
| Dry (%) | Comfortable (%) | |
|---|---|---|
| Jan | 100 | 0 |
| Feb | 100 | 0 |
| Mar | 100 | 0 |
| Apr | 100 | 0 |
| May | 100 | 0 |
| Jun | 99 | 1 |
| Jul | 89 | 11 |
| Aug | 80 | 20 |
| Sep | 92 | 8 |
| Oct | 100 | 0 |
| Nov | 100 | 0 |
| Dec | 100 | 0 |
Wind
Average wind speed through the year, banded into plain-language speed zones so a number reads as 'breezy' or 'calm' without knowing the scale.
This is the average sustained wind speed at the standard 10 metres above open ground — the steady flow a weather station reports, not the sharper gusts that come and go, which can run half again as fast. It's the number that says whether a place is generally breezy or calm.
Across the year, average wind speed in Oak Harbor is typically light breeze, near 8 mph, and varies moderately with the seasons.
The windier part of the year lasts 5.5 months, from around Oct 20 to Apr 4. The windiest month is December, averaging about 11 mph (light breeze).
The calmer part of the year runs from around Apr 5 to Oct 19, with September the calmest month at about 6 mph.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Wind speed (mph) | 10 | 9 | 9 | 8 | 7 | 6 | 7 | 6 | 6 | 8 | 10 | 11 |
| Feels | light breeze | light breeze | light breeze | light breeze | calm | calm | calm | calm | calm | light breeze | light breeze | light breeze |
| Wind speed (mph) | Feels | |
|---|---|---|
| Jan | 10 | light breeze |
| Feb | 9 | light breeze |
| Mar | 9 | light breeze |
| Apr | 8 | light breeze |
| May | 7 | calm |
| Jun | 6 | calm |
| Jul | 7 | calm |
| Aug | 6 | calm |
| Sep | 6 | calm |
| Oct | 8 | light breeze |
| Nov | 10 | light breeze |
| Dec | 11 | light breeze |
Hazard calendar for Oak Harbor
When the seasonal hazards worth planning around — the rainy season, tropical-cyclone risk and dust haze — are active through the year.
Oak Harbor's rainy season runs October–April, when most of the year's rain falls.
Best time to visit Oak Harbor
To characterize how pleasant the weather is in Oak Harbor throughout the year, we compute two travel scores — one for general sightseeing, one for beach and pool weather.
Around late August, Oak Harbor is still near the tail of its best-weather window — great conditions with the peak-season crowds already thinning.
Inferred from the travel-score curve; month-by-month visitor numbers are a planned addition.
The travel score favors clear, rainless days with daytime highs between 64°F and 82°F. Based on this score, the best time of year to visit Oak Harbor for general outdoor tourist activities is from early July to early September, with a peak score in the first week of August.
The travel score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Travel score (0–10) | 0.9 | 1.1 | 1.5 | 2.3 | 3.5 | 4.4 | 6.0 | 6.3 | 4.9 | 3.1 | 1.6 | 0.9 |
| Rating | poor | poor | poor | poor | poor | fair | good | good | fair | poor | poor | poor |
| Travel score (0–10) | Rating | |
|---|---|---|
| Jan | 0.9 | poor |
| Feb | 1.1 | poor |
| Mar | 1.5 | poor |
| Apr | 2.3 | poor |
| May | 3.5 | poor |
| Jun | 4.4 | fair |
| Jul | 6.0 | good |
| Aug | 6.3 | good |
| Sep | 4.9 | fair |
| Oct | 3.1 | poor |
| Nov | 1.6 | poor |
| Dec | 0.9 | poor |
The beach/pool score favors clear, rainless days with daytime highs between 75°F and 93°F. Based on this score, the best time of year to visit Oak Harbor for hot-weather activities is from late July to late August, with a peak score in the first week of August.
The beach/pool score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).
What to pack for Oak Harbor, by month
Month by month, what's worth putting in the bag — from the temperature range, rain chance, sun and wind. Tap a month for a quick packing note.
For a warm-season trip around August (highs near 62°F), the essentials are a warm layer and sun protection. In the cold season around January (highs near 45°F), pack a warm layer, a heavy coat and rain gear.
In August, Oak Harbor sees daytime highs around 62°F and nights near 57°F. Worth packing: a warm layer and sun protection. About 5 days see rain.
Sea temperature near Oak Harbor
Average ocean temperature at the nearest coast, month by month, banded into swim-comfort zones — the other half of the beach question.
The sea at the nearest coast (about 12 mi away) is warmest in August at about 54°F and coldest in February near 46°F.
The water stays below 68°F all year — cool enough that most swimmers want a wetsuit.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°F) | 46 | 46 | 47 | 48 | 50 | 52 | 53 | 54 | 53 | 50 | 49 | 47 |
| Comfort | Bracing | Bracing | Bracing | Bracing | Bracing | Bracing | Bracing | Bracing | Bracing | Bracing | Bracing | Bracing |
| Sea temperature (°F) | Comfort | |
|---|---|---|
| Jan | 46 | Bracing |
| Feb | 46 | Bracing |
| Mar | 47 | Bracing |
| Apr | 48 | Bracing |
| May | 50 | Bracing |
| Jun | 52 | Bracing |
| Jul | 53 | Bracing |
| Aug | 54 | Bracing |
| Sep | 53 | Bracing |
| Oct | 50 | Bracing |
| Nov | 49 | Bracing |
| Dec | 47 | Bracing |
UV index (midday) in Oak Harbor by month
Clear-sky midday UV index through the year, shaded by the WHO exposure levels — how much sun protection each month calls for.
Under clear skies, the midday UV index in Oak Harbor peaks around July 17 at about 8 (very high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near December 18 at about 1 (low).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 7 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 1 | 1 | 4 | 5 | 7 | 6 | 8 | 6 | 4 | 3 | 1 | 1 |
| Level | Low | Low | Moderate | Moderate | High | High | Very high | High | Moderate | Moderate | Low | Low |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 1 | Low |
| Feb | 1 | Low |
| Mar | 4 | Moderate |
| Apr | 5 | Moderate |
| May | 7 | High |
| Jun | 6 | High |
| Jul | 8 | Very high |
| Aug | 6 | High |
| Sep | 4 | Moderate |
| Oct | 3 | Moderate |
| Nov | 1 | Low |
| Dec | 1 | Low |
Average hourly UV index in Oak Harbor
Modeled clear-sky UV for every hour of every day — when in the day sun protection actually matters.
The whole year hour by hour: each column is a day, each row an hour, and the color is the modeled clear-sky UV index — the midday peak scaled down as the sun sits lower in the sky. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.
UV falls off far faster than brightness as the sun drops, so even in July the burn window is concentrated in the middle of the day: about 8.5 hours a day reach index 3 (protection recommended), and 4.5 hours reach 6 or more. Mornings and late afternoons stay comparatively gentle year round.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV ≥ 3 (h/day) | 0 | 0 | 2.5 | 5 | 7 | 7 | 8.5 | 7 | 4 | 0 | 0 | 0 |
| UV ≥ 6 (h/day) | 0 | 0 | 0 | 0 | 2.5 | 0 | 4.5 | 1.5 | 0 | 0 | 0 | 0 |
| UV ≥ 3 (h/day) | UV ≥ 6 (h/day) | |
|---|---|---|
| Jan | 0 | 0 |
| Feb | 0 | 0 |
| Mar | 2.5 | 0 |
| Apr | 5 | 0 |
| May | 7 | 2.5 |
| Jun | 7 | 0 |
| Jul | 8.5 | 4.5 |
| Aug | 7 | 1.5 |
| Sep | 4 | 0 |
| Oct | 0 | 0 |
| Nov | 0 | 0 |
| Dec | 0 | 0 |
Growing season
Oak Harbor is frost-free year round — even the coldest nights rarely reach freezing, so there is no start or end to the growing season.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Frost-free chance (%) | 99 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 |
| Frost nights | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Frost-free chance (%) | Frost nights | |
|---|---|---|
| Jan | 99 | 0 |
| Feb | 100 | 0 |
| Mar | 100 | 0 |
| Apr | 100 | 0 |
| May | 100 | 0 |
| Jun | 100 | 0 |
| Jul | 100 | 0 |
| Aug | 100 | 0 |
| Sep | 100 | 0 |
| Oct | 100 | 0 |
| Nov | 100 | 0 |
| Dec | 100 | 0 |
Growing degree days
Growing degree days tally heat above 50°F: each day adds however many degrees its average temperature runs over that threshold, and cold days add nothing. Oak Harbor banks about 1,115 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around August.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Growing degree days (°F·days) | 0 | 0 | 0 | 1 | 80 | 166 | 277 | 301 | 218 | 71 | 0 | 0 |
| Growing degree days (°F·days) | |
|---|---|
| Jan | 0 |
| Feb | 0 |
| Mar | 0 |
| Apr | 1 |
| May | 80 |
| Jun | 166 |
| Jul | 277 |
| Aug | 301 |
| Sep | 218 |
| Oct | 71 |
| Nov | 0 |
| Dec | 0 |
Solar energy
Average daily shortwave solar energy reaching the ground, banded into brightness zones so the number means something at a glance.
Solar energy is how much sunlight actually reaches the ground each day, measured in kilowatt-hours per square metre (kWh/m²) — the combined effect of how long the sun is up, how high it climbs, and how much cloud gets in the way. It's the raw fuel a solar panel has to work with: for scale, 1 kWh/m² a day is dim and wintry, while 7+ is desert-bright.
Oak Harbor receives about 3.5 kWh/m² a day of solar energy on average — moderate — with a clear seasonal swing between 0.8 and 6.3 kWh/m².
The brighter stretch of the year lasts 6.0 months, from around Mar 26 to Sep 25. The brightest month is July, averaging about 6.2 kWh/m² (intense).
The dimmest month is December, down near 0.9 kWh/m² — roughly 86% less than the July peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Solar energy (kWh/m²) | 1.1 | 1.9 | 3.1 | 4.5 | 5.6 | 5.8 | 6.3 | 5.5 | 4.1 | 2.3 | 1.2 | 0.9 |
| Level | Dim | Dim | Moderate | Bright | Bright | Bright | Intense | Bright | Bright | Moderate | Dim | Dim |
| Solar energy (kWh/m²) | Level | |
|---|---|---|
| Jan | 1.1 | Dim |
| Feb | 1.9 | Dim |
| Mar | 3.1 | Moderate |
| Apr | 4.5 | Bright |
| May | 5.6 | Bright |
| Jun | 5.8 | Bright |
| Jul | 6.3 | Intense |
| Aug | 5.5 | Bright |
| Sep | 4.1 | Bright |
| Oct | 2.3 | Moderate |
| Nov | 1.2 | Dim |
| Dec | 0.9 | Dim |
Where is Oak Harbor?
Oak Harbor sits at 48.3°N, 122.6°W, 95 ft above sea level, in United States. The nearest listed city is Anacortes, 15 mi away.
Topography around Oak Harbor
How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Oak Harbor.
Within 2 miles, the terrain around Oak Harbor has only modest variations in elevation — a maximum elevation change of 354 ft around an average of 89 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 771 ft; within 50 miles, extreme variations in elevation — a maximum elevation change of 9,780 ft.
The land around Oak Harbor is covered by water (29%), trees (28%) and grassland (24%) within 2 miles, water (61%) and trees (23%) within 10 miles, and trees (53%) and water (34%) within 50 miles.
United States travel facts
- Power plugs
- Type A / B
- 120 V · 60 Hz
- Prices
- ≈ 100% of US
- price level, 2025
- GDP per capita
- $90,027
- 2025
- Happiness
- 6.8 / 10
- World Happiness, 2025
- Safe drinking water
- 98%
- of population, 2024
- Homicide rate
- 5.8
- per 100k, 2023
- Road deaths
- 12.7
- per 100k/yr, 2019
- Income group
- High
- World Bank
- Religion
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Oak Harbor (48.2932°, -122.6432°, elevation 95 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).