Pool swim season in West Allis, WI
Swim season in West Allis without a heater, and with one
An unheated pool in West Allis never reaches 78°F in a normal year. It peaks around 76°F in Aug. The air allows up to 4 swimmable months with a heater (Jun to Sep).
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What each heater buys you in West Allis
| 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 | 4 | Jun to Sep | $115 | $665 |
| Gas heater + cover | 4 | Jun to Sep | $135 | $560 |
For a 450 sq ft pool held at 80°F, at WI prices of 19.1¢/kWh electricity and $11/Mcf gas. All-in spreads the purchase over the equipment's life.
The cheapest way to the full season in West Allis
Solar panels + cover: 4 of 4 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 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: West Allis, 1.6 mi away (NOAA 1991–2020 normals). Water temperature is estimated from air and sunshine, not measured.
West Allis 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 | 31° | 23° | 1.6 | 24° | 30° | – | – |
| Feb | 34° | 26° | 2.7 | 24° | 30° | – | – |
| Mar | 45° | 36° | 3.7 | 31° | 37° | – | – |
| Apr | 57° | 47° | 4.6 | 43° | 49° | – | – |
| May | 70° | 59° | 5.5 | 55° | 61° | – | – |
| Jun | 80° | 69° | 6.1 | 67° | 73° | $73 | $87 |
| Jul | 85° | 74° | 6.2 | 75° | 81° | – | – |
| Aug | 83° | 72° | 5.3 | 76° | 82° | – | – |
| Sep | 77° | 65° | 4.2 | 70° | 76° | $42 | $48 |
| Oct | 62° | 52° | 2.7 | 58° | 64° | – | – |
| Nov | 48° | 39° | 1.8 | 44° | 50° | – | – |
| Dec | 36° | 28° | 1.3 | 32° | 38° | – | – |
Heating costs most in Jun (about $73 with a heat pump, $87 with gas). Sunshine peaks in Jul at 6.2 kWh/m²/day (NASA satellite data, 66.8 km grid cell). Highlighted months are swimmable with no heater.
How West Allis compares with nearby cities
West Allis ranks 5 of 98 Wisconsin cities for unheated swim months, and no nearby city gets a longer unheated season.
| City | Distance | Unheated months | Heat pump months | Heat pump $/yr |
|---|---|---|---|---|
| Greenfield, WI | 3 mi | 0 | 4 | $190 |
| Wauwatosa, WI | 4 mi | 0 | 4 | $149 |
| Greendale, WI | 5 mi | 0 | 4 | $190 |
| Milwaukee, WI | 5 mi | 0 | 4 | $153 |
| New Berlin, WI | 6 mi | 0 | 4 | $190 |
| Brookfield, WI | 6 mi | 0 | 4 | $215 |