Pool swim season in Mount Vernon, NY
Swim season in Mount Vernon without a heater, and with one
An unheated pool in Mount Vernon reaches 78°F in Jul to Aug, about 2 months a year. The air allows up to 5 swimmable months with a heater (May to Sep).
- J
- F
- M
- A
- M
- J
- J
- A
- S
- O
- N
- D
What each heater buys you in Mount Vernon
| Option | Months | Swimmable | Energy/yr | All-in/yr |
|---|---|---|---|---|
| No heater | 2 | Jul to Aug | $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 | $273 | $823 |
| Gas heater + cover | 5 | May to Sep | $328 | $753 |
For a 450 sq ft pool held at 80°F, at NY prices of 29.3¢/kWh electricity and $18/Mcf gas. All-in spreads the purchase over the equipment's life.
The cheapest way to the full season in Mount Vernon
Solar panels + cover: 4 of 5 possible months for about $283 a year all-in, which works out near $142 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: Bronx, 5.4 mi away (NOAA 1991–2020 normals). Water temperature is estimated from air and sunshine, not measured.
Mount Vernon 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 | 40° | 34° | 1.9 | 35° | 41° | – | – |
| Feb | 43° | 36° | 2.8 | 34° | 40° | – | – |
| Mar | 50° | 42° | 3.8 | 40° | 46° | – | – |
| Apr | 61° | 53° | 5.0 | 50° | 56° | – | – |
| May | 72° | 63° | 5.6 | 61° | 67° | $229 | $270 |
| Jun | 81° | 73° | 6.1 | 71° | 77° | $44 | $58 |
| Jul | 86° | 78° | 6.2 | 79° | 85° | – | – |
| Aug | 84° | 77° | 5.5 | 80° | 86° | – | – |
| Sep | 77° | 70° | 4.4 | 75° | 81° | – | – |
| Oct | 66° | 58° | 3.0 | 64° | 70° | – | – |
| Nov | 54° | 48° | 2.1 | 52° | 58° | – | – |
| Dec | 45° | 39° | 1.6 | 42° | 48° | – | – |
Heating costs most in May (about $229 with a heat pump, $270 with gas). Sunshine peaks in Jul at 6.2 kWh/m²/day (NASA satellite data, 53.7 km grid cell). Highlighted months are swimmable with no heater.
How Mount Vernon compares with nearby cities
Mount Vernon ranks 1 of 90 New York cities for unheated swim months, and no nearby city gets a longer unheated season.
| City | Distance | Unheated months | Heat pump months | Heat pump $/yr |
|---|---|---|---|---|
| New Rochelle, NY | 3 mi | 0 | 5 | $394 |
| Yonkers, NY | 3 mi | 0 | 5 | $394 |
| Mamaroneck, NY | 6 mi | 0 | 5 | $394 |
| Scarsdale, NY | 6 mi | 0 | 5 | $394 |
| Tenafly, NJ | 6 mi | 2 | 5 | $227 |
| Dobbs Ferry, NY | 7 mi | 0 | 5 | $404 |