Pool swim season in Oak Harbor, WA
When can you swim in an outdoor pool in Oak Harbor, WA?
An unheated pool in Oak Harbor never reaches 78°F in a normal year. It peaks around 64°F in Aug. The air allows up to 0 swimmable months with a heater (no month).
- J
- F
- M
- A
- M
- J
- J
- A
- S
- O
- N
- D
Heater options for a Oak Harbor pool, side by side
| Option | Months | Swimmable | Energy/yr | All-in/yr |
|---|---|---|---|---|
| No heater | 0 | no month | $0 | $0 |
| Solar cover only | 0 | no month | $0 | $50 |
| Solar panels + cover | 0 | no month | $0 | $283 |
| Heat pump + cover | 0 | no month | $0 | $550 |
| Gas heater + cover | 0 | no month | $0 | $425 |
For a 450 sq ft pool held at 80°F, at WA prices of 14.4¢/kWh electricity and $18/Mcf gas. All-in spreads the purchase over the equipment's life.
Do you need a pool heater in Oak Harbor?
No. Your pool is already warm for every month the air allows. A heater adds nothing.
No heater makes outdoor swimming practical here: the air is too cold in every month. If you want to swim at home, price an enclosure or an indoor pool instead, and see why a cover cannot fix this and where solar panels stop working.
Weather station: Whidbey Island Nas, 4.3 mi away (NOAA 1991–2020 normals). Water temperature is estimated from air and sunshine, not measured.
Oak Harbor month by month: air, sun and pool water
| Month | Air high | Air avg | Sun kWh/m²/day | Water, unheated | Water, covered | Heat pump $ | Gas $ |
|---|---|---|---|---|---|---|---|
| Jan | 49° | 44° | 1.0 | 42° | 48° | – | – |
| Feb | 51° | 44° | 1.9 | 43° | 49° | – | – |
| Mar | 55° | 47° | 2.9 | 46° | 52° | – | – |
| Apr | 58° | 51° | 4.3 | 50° | 56° | – | – |
| May | 62° | 55° | 5.5 | 56° | 62° | – | – |
| Jun | 66° | 59° | 6.0 | 60° | 66° | – | – |
| Jul | 69° | 62° | 6.5 | 64° | 70° | – | – |
| Aug | 70° | 62° | 5.5 | 64° | 70° | – | – |
| Sep | 67° | 59° | 3.9 | 61° | 67° | – | – |
| Oct | 60° | 53° | 2.2 | 55° | 61° | – | – |
| Nov | 54° | 47° | 1.1 | 48° | 54° | – | – |
| Dec | 49° | 43° | 0.8 | 43° | 49° | – | – |
Sunshine peaks in Jul at 6.5 kWh/m²/day (NASA satellite data, 24.8 km grid cell). Highlighted months are swimmable with no heater.
How Oak Harbor compares with nearby cities
Oak Harbor ranks 89 of 91 Washington cities for unheated swim months, and no nearby city gets a longer unheated season.
| City | Distance | Unheated months | Heat pump months | Heat pump $/yr |
|---|---|---|---|---|
| Anacortes, WA | 13 mi | 0 | 3 | $215 |
| Port Townsend, WA | 14 mi | 0 | 2 | $152 |
| Mount Vernon, WA | 17 mi | 0 | 2 | $141 |
| Burlington, WA | 18 mi | 0 | 2 | $141 |
| Sedro-Woolley, WA | 24 mi | 0 | 2 | $138 |
| Arlington, WA | 24 mi | 0 | 4 | $426 |