Finger Lakes · Genesee Valley
Monroe County weather and solar
What the climate here actually does to a solar array — production by season, the structural spec the snow load forces, and the roof decisions that follow from both.
The climate
Genesee Valley
Specific yield
1,100–1,240 kWh / kW-DC / yr
A 10 kW array averages about 11,700 kWh a year here.
Modeled NREL PVWatts v8 · verified Jan 2026
Mean annual snowfall
65–110 inches
Moderate lake-effect exposure from Lake Ontario.
Modeled NOAA/NWS seasonal snowfall records · verified Jan 2026Rochester's long-term mean is roughly 100 inches; the farm counties south and west run lower.
Design ground snow load
40–60 psf
Racking and structural review are engineered to this figure. Ask which number your proposal used.
Filed ASCE 7 ground snow load data · verified Jan 2026
Winter quarter share
11% of annual
December, January, and February combined.
Derived NREL PVWatts v8 · verified Jan 2026
Days with snow on the array
18–40 per season
Far fewer than days with snow on the ground — panels shed.
Observed GridReady quote and bill review sample · verified Jan 2026
Seasonality
Production month by month on a 10 kW array
kWh per month from a 10 kW-DC array at the midpoint of the Genesee Valley yield band. Bar height is relative to the peak month.
Show the arithmetic
10 kW × 1,170 kWh/kW/yr (midpoint of the Genesee Valley band) = 11,700 kWh a year, distributed on a northern-temperate seasonal curve anchored so December through February sums to 11% of the total.
A modeled shape, not a measurement of your roof. Orientation, pitch, and shading move individual months more than they move the annual total.
Derived NREL PVWatts v8 · verified Jan 2026
Local weather
What the weather here specifically does
- Rochester sits in a relative gap between the Erie and Ontario snow belts. It still gets 100 inches a year, but the extreme single-event totals that hit Buffalo's southtowns are rarer here.
- Open agricultural land west and south of the city means less tree shading and more usable ground-mount siting than most of upstate.
- RG&E's high basic service charge means the fixed floor on a Rochester bill is larger than a Buffalo one — worth naming when someone models a near-zero bill.
The roof
Consequences for the array itself
- Rochester's older neighborhoods carry a heavy mature canopy. Suburban Monroe County generally does not. The two halves of this market have genuinely different shading realities.
- Large rural parcels make ground mounts practical, and Wyoming and Livingston county AHJs are generally comfortable permitting them.
The one question worth asking every installer here
“What ground snow load is this racking engineered for, and can I see the stamped calculation?” The right answer in Monroe County is 40–60 psf. A proposal that cannot answer has not been engineered for this roof.
Microclimates
Monroe County is not one climate
| Zone | Snowfall | Snow load | Specific yield |
|---|---|---|---|
| Genesee Valley (primary) | 65–110" | 40–60 psf | 1,100–1,240 kWh/kW |
| Lake Ontario Plain | 80–140" | 50–80 psf | 1,080–1,220 kWh/kW |
By location
Elevation across Monroe County
| Place | Elevation | Climate zone | Guide |
|---|---|---|---|
| Churchville | 570 ft | Genesee Valley | Costs & production |
| Henrietta | 550 ft | Genesee Valley | Costs & production |
| Brockport | 540 ft | Lake Ontario Plain | Costs & production |
| Brighton | 525 ft | Genesee Valley | Costs & production |
| Rochester | 505 ft | Genesee Valley | Costs & production |
| Penfield | 500 ft | Genesee Valley | Costs & production |
| Pittsford | 500 ft | Genesee Valley | Costs & production |
| Fairport | 460 ft | Genesee Valley | Costs & production |
| Irondequoit | 400 ft | Lake Ontario Plain | Costs & production |
| Webster | 400 ft | Lake Ontario Plain | Costs & production |
| Greece | 350 ft | Lake Ontario Plain | Costs & production |
Questions
Monroe County climate FAQ
- How much does snow reduce solar production in Monroe County?
- Less than most people expect. A pitched array here sees roughly 18 to 40 days a season with enough cover to stop production — the glass is slick and the array runs warmer than the shingles around it. Cloud cover through November and December costs more production than snow cover does. What snow really drives is the structural spec: design ground snow load here is 40 to 60 psf, and racking must be engineered and stamped for it.
- What is the seasonal production curve in Monroe County?
- Jul is the strongest month and Dec the weakest, by roughly 3.9 to one. December through February combined account for about 11% of annual output — roughly one month's worth of production spread across three months. A proposal that shows a smooth, near-flat monthly production curve for this county is not modeling this climate.
- Is Monroe County too far north or too cloudy for solar?
- No, but the honest framing is that the climate sets the ceiling and the electricity rate sets the value. A 10 kW array here produces roughly 11,700 kWh a year. That is real output — the question is what a kWh is worth where you live, which is a rate question rather than a weather one.
- How does lake-effect snow affect solar in Monroe County?
- Moderate exposure from Lake Ontario. Rochester sits in a relative gap between the Erie and Ontario snow belts. It still gets 100 inches a year, but the extreme single-event totals that hit Buffalo's southtowns are rarer here.
- Does cold weather help or hurt solar panels in Monroe County?
- Cold helps efficiency — panels produce more per unit of sunlight at low temperature, which is why a clear February day can outperform a hazy July one on a per-hour basis. What hurts is daylight hours and cloud cover, and this climate is short on both between November and February. The two effects do not cancel out; the daylight loss dominates.
Next step
Turn this into your own numbers
The climate sets what a roof can produce. Your rate sets what that production is worth, and your roof sets how much of the band you actually get.
How this page is built
This is a generated page: the structure is shared across locations, the numbers are not. Every figure comes from the source cited beside it, with the date we last checked it. Nothing here is a quote, an appraisal, or tax advice, and none of it is specific to your roof.
Rates and incentive programs change. We re-verify utility tariffs and NYSERDA program status on a rolling schedule and stamp the date on each number rather than on the page, so you can see which specific figures are fresh. Full methodology · Program status tracker · About the Local Energy Playbook
Page content last reviewed April 2026.