Ithaca weather by month
Ithaca runs from about 0°C in January to 24°C in July, with April the wettest month at 147 mm.
warmest month
July
24°C
coolest month
January
0°C
wettest month
April
147 mm
worst air month
August
10 µg/m³
The whole year, month by month.
| Month | Avg temp | Rain | Sun | PM2.5 |
|---|---|---|---|---|
| January | 0°C | 130 mm | 90 h | 5 |
| February | 1°C | 38 mm | 210 h | 10 |
| March | 5°C | 111 mm | 197 h | 8 |
| April | 10°C | 147 mm | 217 h | 7 |
| May | 17°C | 102 mm | 320 h | 6 |
| June | 22°C | 108 mm | 332 h | 7 |
| July | 24°C | 107 mm | 390 h | 10 |
| August | 21°C | 120 mm | 308 h | 10 |
| September | 19°C | 77 mm | 264 h | 7 |
| October | 12°C | 63 mm | 257 h | 4 |
| November | 7°C | 93 mm | 167 h | 4 |
| December | 0°C | 77 mm | 109 h | 4 |
About 2,861 hours of sun a year. Roughly 118 rainy days a year.
These are long-run climate normals, not a forecast. A given year can sit well outside them. PM2.5 is a global model: near the coast it counts sea salt as fine particulate and reads high against ground stations, sometimes by a factor of two. Use the shape of the year, not the absolute number.
where these numbers come from
- · Temperature, rainfall and sunshine: ECMWF ERA5 reanalysis climate normals via Open-Meteo (CC BY 4.0), fetched once and stored.
- · PM2.5: Copernicus CAMS reanalysis, monthly means. Modelled, not station readings; near coasts CAMS counts sea salt as PM2.5 and reads high.
Last reviewed 2026-05-27. Full method, licences and the list of sources we rejected are on the methodology page.