Pool swim season in Portsmouth, OH
Portsmouth, OH: how long the pool season really is
An unheated pool in Portsmouth never reaches 78°F in a normal year. It peaks around 78°F in Aug. The air allows up to 5 swimmable months with a heater (May to Sep).
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What each heater buys you in Portsmouth
| Option | Months | Swimmable | Energy/yr | All-in/yr |
|---|---|---|---|---|
| No heater | 0 | no month | $0 | $0 |
| Solar cover only | 3 | Jul to Sep | $0 | $50 |
| Solar panels + cover | 4 | Jun to Sep | $0 | $283 |
| Heat pump + cover | 5 | May to Sep | $168 | $718 |
| Gas heater + cover | 5 | May to Sep | $251 | $676 |
For a 450 sq ft pool held at 80°F, at OH prices of 18.8¢/kWh electricity and $14/Mcf gas. All-in spreads the purchase over the equipment's life.
The cheapest way to the full season in Portsmouth
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 3 months here for about $50 a year (why a cover comes first). If you get quotes, ask for gas as well as a heat pump: once the purchase price is counted, gas comes out cheaper all-in here (heat pump or gas).
Weather station: Portsmouth-Sciotoville, 3.4 mi away (NOAA 1991–2020 normals). Water temperature is estimated from air and sunshine, not measured.
Portsmouth 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 | 41° | 32° | 1.9 | 33° | 39° | – | – |
| Feb | 45° | 35° | 2.6 | 33° | 39° | – | – |
| Mar | 55° | 44° | 3.7 | 40° | 46° | – | – |
| Apr | 67° | 55° | 5.0 | 51° | 57° | – | – |
| May | 76° | 64° | 5.5 | 62° | 68° | $133 | $194 |
| Jun | 83° | 72° | 6.2 | 71° | 77° | $25 | $41 |
| Jul | 87° | 76° | 5.9 | 77° | 83° | – | – |
| Aug | 86° | 75° | 5.5 | 78° | 84° | – | – |
| Sep | 80° | 68° | 4.6 | 73° | 79° | $10 | $16 |
| Oct | 69° | 56° | 3.3 | 63° | 69° | – | – |
| Nov | 56° | 45° | 2.3 | 50° | 56° | – | – |
| Dec | 46° | 37° | 1.6 | 39° | 45° | – | – |
Heating costs most in May (about $133 with a heat pump, $194 with gas). Sunshine peaks in Jun at 6.2 kWh/m²/day (NASA satellite data, 48.2 km grid cell). Highlighted months are swimmable with no heater.
How Portsmouth compares with nearby cities
Portsmouth ranks 9 of 176 Ohio cities for unheated swim months; Huntington nearby gets a longer season without a heater.
| City | Distance | Unheated months | Heat pump months | Heat pump $/yr |
|---|---|---|---|---|
| Ironton, OH | 21 mi | 0 | 5 | $205 |
| Ashland, KY | 26 mi | 0 | 5 | $155 |
| Huntington, WV | 37 mi | 1 | 5 | $112 |
| Chillicothe, OH | 41 mi | 0 | 5 | $216 |
| Circleville, OH | 59 mi | 0 | 5 | $179 |
| Washington Court House, OH | 60 mi | 0 | 5 | $257 |