Winthrop, NY Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Winthrop, a community in St. Lawrence County, New York.
This Afternoon
63°F
Sunny
Sunny, with a high near 63. Northeast wind around 5 mph.
7-day forecast for Winthrop
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 63°F | Sunny | 5 mph NE | 0% |
| Tonight | 42°F | Mostly Cloudy | 0 to 3 mph E | 1% |
| Sunday | 58°F | Rain Showers | 0 to 5 mph E | 78% |
| Sunday Night | 41°F | Mostly Cloudy | 0 to 3 mph N | 3% |
| Monday | 59°F | Partly Sunny | 3 to 7 mph N | 0% |
| Monday Night | 39°F | Mostly Cloudy | 1 to 5 mph NE | 0% |
| Tuesday | 61°F | Mostly Sunny | 3 to 9 mph NE | 0% |
| Tuesday Night | 39°F | Partly Cloudy | 2 to 8 mph NE | 0% |
| Wednesday | 66°F | Mostly Sunny | 2 to 8 mph NE | 1% |
| Wednesday Night | 41°F | Partly Cloudy | 1 to 7 mph E | 3% |
| Thursday | 65°F | Partly Sunny | 1 to 7 mph E | 7% |
| Thursday Night | 42°F | Mostly Cloudy | 1 to 6 mph NE | 13% |
| Friday | 66°F | Partly Sunny then Slight Chance Rain Showers | 1 to 8 mph NE | 15% |
| Friday Night | 43°F | Slight Chance Rain Showers then Partly Cloudy | 2 to 6 mph NE | 15% |
Forecast source: National Weather Service (api.weather.gov) for Winthrop (44.804, -74.810). Updated through the day.
Growing snapshot for Winthrop
Last spring frost
May 10
First fall frost
Oct 5
Growing season
148 days
Hardiness zone
4b
More local growing data for Winthrop: nearby ZIP 13697 weather · frost dates · planting calendar · New York frost dates
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Madrid
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Norfolk
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Rensselaer Falls
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Waddington
Climate data from the nearest NOAA station, Lawrenceville 3 Sw, Ny (6.9 mi from Winthrop). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.