Pool swim season in Avenal, CA
Avenal, CA: how long the pool season really is
An unheated pool in Avenal 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 Avenal pool, side by side
| Option | Months | Swimmable | Energy/yr | All-in/yr |
|---|---|---|---|---|
| No heater | 4 | Jun to Sep | $0 | $0 |
| Solar cover only | 5 | Jun to Oct | $0 | $50 |
| Solar panels + cover | 7 | Apr to Oct | $0 | $283 |
| Heat pump + cover | 7 | Apr to Oct | $304 | $854 |
| Gas heater + cover | 7 | Apr to Oct | $405 | $830 |
For a 450 sq ft pool held at 80°F, at CA prices of 32.6¢/kWh electricity and $22/Mcf gas. All-in spreads the purchase over the equipment's life.
The cheapest way to the full season in Avenal
Solar panels + cover: 7 of 7 possible months for about $283 a year all-in, which works out near $94 for each month it adds.
Before you pay for any heater, buy a solar cover: on its own it adds 1 month 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: Kettleman City, 8.9 mi away (NOAA 1991–2020 normals). Water temperature is estimated from air and sunshine, not measured.
Avenal 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° | 46° | 2.6 | 46° | 52° | – | – |
| Feb | 63° | 52° | 3.7 | 50° | 56° | – | – |
| Mar | 70° | 56° | 5.1 | 56° | 62° | – | – |
| Apr | 76° | 62° | 6.5 | 63° | 69° | $225 | $292 |
| May | 84° | 70° | 7.7 | 71° | 77° | $61 | $88 |
| Jun | 92° | 77° | 8.5 | 79° | 85° | – | – |
| Jul | 99° | 83° | 8.2 | 85° | 91° | – | – |
| Aug | 98° | 82° | 7.5 | 87° | 93° | – | – |
| Sep | 92° | 76° | 6.2 | 82° | 88° | – | – |
| Oct | 81° | 66° | 4.6 | 73° | 79° | $18 | $25 |
| Nov | 67° | 54° | 3.2 | 61° | 67° | – | – |
| Dec | 58° | 47° | 2.4 | 50° | 56° | – | – |
Heating costs most in Apr (about $225 with a heat pump, $292 with gas). Sunshine peaks in Jun at 8.5 kWh/m²/day (NASA satellite data, 62.5 km grid cell). Highlighted months are swimmable with no heater.
How Avenal compares with nearby cities
Avenal ranks 27 of 376 California cities for unheated swim months, and no nearby city gets a longer unheated season.
| City | Distance | Unheated months | Heat pump months | Heat pump $/yr |
|---|---|---|---|---|
| Coalinga, CA | 14 mi | 4 | 8 | $572 |
| Lemoore, CA | 25 mi | 3 | 7 | $371 |
| Corcoran, CA | 31 mi | 4 | 7 | $329 |
| Hanford, CA | 33 mi | 4 | 7 | $317 |
| El Paso de Robles (Paso Robles), CA | 41 mi | 0 | 7 | $683 |
| Tulare, CA | 45 mi | 3 | 7 | $387 |