Pool swim season in Martinsburg, WV
Swim season in Martinsburg without a heater, and with one
An unheated pool in Martinsburg never reaches 78°F in a normal year. It peaks around 77°F in Aug. The air allows up to 5 swimmable months with a heater (May to Sep).
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Heater options for a Martinsburg pool, side by side
| Option | Months | Swimmable | Energy/yr | All-in/yr |
|---|---|---|---|---|
| No heater | 0 | no month | $0 | $0 |
| Solar cover only | 2 | Jul to Aug | $0 | $50 |
| Solar panels + cover | 4 | Jun to Sep | $0 | $283 |
| Heat pump + cover | 5 | May to Sep | $181 | $731 |
| Gas heater + cover | 5 | May to Sep | $320 | $745 |
For a 450 sq ft pool held at 80°F, at WV prices of 15.6¢/kWh electricity and $14/Mcf gas. All-in spreads the purchase over the equipment's life.
The cheapest way to the full season in Martinsburg
Solar panels + cover: 4 of 5 possible months for about $283 a year all-in, which works out near $71 for each month it adds.
Before you pay for any heater, buy a solar cover: on its own it adds 2 months here for about $50 a year (why a cover comes first). 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: Martinsburg 2, 0.8 mi away (NOAA 1991–2020 normals). Water temperature is estimated from air and sunshine, not measured.
Martinsburg 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 | 42° | 32° | 2.0 | 33° | 39° | – | – |
| Feb | 45° | 34° | 2.8 | 33° | 39° | – | – |
| Mar | 54° | 42° | 3.8 | 39° | 45° | – | – |
| Apr | 66° | 53° | 4.9 | 49° | 55° | – | – |
| May | 75° | 63° | 5.4 | 60° | 66° | $128 | $220 |
| Jun | 83° | 71° | 6.1 | 70° | 76° | $32 | $61 |
| Jul | 87° | 76° | 6.0 | 77° | 83° | – | – |
| Aug | 86° | 74° | 5.3 | 77° | 83° | – | – |
| Sep | 79° | 67° | 4.3 | 72° | 78° | $21 | $39 |
| Oct | 67° | 55° | 3.1 | 61° | 67° | – | – |
| Nov | 56° | 44° | 2.3 | 49° | 55° | – | – |
| Dec | 45° | 36° | 1.7 | 39° | 45° | – | – |
Heating costs most in May (about $128 with a heat pump, $220 with gas). Sunshine peaks in Jun at 6.1 kWh/m²/day (NASA satellite data, 41.3 km grid cell). Highlighted months are swimmable with no heater.
How Martinsburg compares with nearby cities
Martinsburg ranks 6 of 13 West Virginia cities for unheated swim months; Frederick nearby gets a longer season without a heater.
| City | Distance | Unheated months | Heat pump months | Heat pump $/yr |
|---|---|---|---|---|
| Hagerstown, MD | 18 mi | 0 | 5 | $221 |
| Winchester, VA | 22 mi | 0 | 5 | $194 |
| Waynesboro, PA | 29 mi | 0 | 5 | $313 |
| Frederick, MD | 30 mi | 2 | 5 | $131 |
| Leesburg, VA | 33 mi | 0 | 5 | $198 |
| Chambersburg, PA | 37 mi | 0 | 5 | $274 |