Pool swim season in Wilmington, NC
Wilmington, NC: how long the pool season really is
An unheated pool in Wilmington reaches 78°F in Jun to Sep, about 4 months a year. The air allows up to 7 swimmable months with a heater (Apr to Oct).
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Heater options for a Wilmington pool, side by side
| Option | Months | Swimmable | Energy/yr | All-in/yr |
|---|---|---|---|---|
| No heater | 4 | Jun to Sep | $0 | $0 |
| Solar cover only | 4 | Jun to Sep | $0 | $50 |
| Solar panels + cover | 6 | May to Oct | $0 | $283 |
| Heat pump + cover | 7 | Apr to Oct | $150 | $700 |
| Gas heater + cover | 7 | Apr to Oct | $334 | $759 |
For a 450 sq ft pool held at 80°F, at NC prices of 14.9¢/kWh electricity and $16/Mcf gas. All-in spreads the purchase over the equipment's life.
The cheapest way to the full season in Wilmington
Solar panels + cover: 6 of 7 possible months for about $283 a year all-in, which works out near $142 for each month it adds.
A solar cover alone adds no swim months here, so if you want a longer season you need a heater (why); still use one at night to hold the heat you pay for. If you get quotes, ask for a heat pump sized to your pool's surface area; here it beats gas all-in (heat pump or gas).
Weather station: Wilmington International Airport, 4.1 mi away (NOAA 1991–2020 normals). Water temperature is estimated from air and sunshine, not measured.
Wilmington 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 | 57° | 47° | 2.7 | 48° | 54° | – | – |
| Feb | 60° | 49° | 3.4 | 49° | 55° | – | – |
| Mar | 67° | 55° | 4.6 | 54° | 60° | – | – |
| Apr | 75° | 64° | 5.8 | 62° | 68° | $103 | $224 |
| May | 81° | 71° | 6.3 | 71° | 77° | $26 | $63 |
| Jun | 87° | 78° | 6.5 | 78° | 84° | – | – |
| Jul | 90° | 82° | 6.3 | 83° | 89° | – | – |
| Aug | 88° | 80° | 5.6 | 83° | 89° | – | – |
| Sep | 84° | 75° | 4.7 | 79° | 85° | – | – |
| Oct | 76° | 66° | 3.9 | 72° | 78° | $21 | $47 |
| Nov | 67° | 56° | 3.0 | 61° | 67° | – | – |
| Dec | 60° | 50° | 2.4 | 52° | 58° | – | – |
Heating costs most in Apr (about $103 with a heat pump, $224 with gas). Sunshine peaks in Jun at 6.5 kWh/m²/day (NASA satellite data, 48.0 km grid cell). Highlighted months are swimmable with no heater.
How Wilmington compares with nearby cities
Wilmington ranks 2 of 91 North Carolina cities for unheated swim months, and no nearby city gets a longer unheated season.
| City | Distance | Unheated months | Heat pump months | Heat pump $/yr |
|---|---|---|---|---|
| Leland, NC | 9 mi | 3 | 7 | $156 |
| Jacksonville, NC | 46 mi | 3 | 7 | $171 |
| North Myrtle Beach, SC | 54 mi | 3 | 7 | $173 |
| Myrtle Beach, SC | 67 mi | 2 | 7 | $219 |
| Lumberton, NC | 71 mi | 3 | 7 | $207 |
| Conway, SC | 71 mi | 4 | 7 | $154 |