New Castle Northwest, PA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for New Castle Northwest, a community in Lawrence County, Pennsylvania.
Today
86°F
Areas Of Fog then Sunny
Areas of fog before 9am. Sunny, with a high near 86. East wind around 2 mph.
7-day forecast for New Castle Northwest
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 86°F | Areas Of Fog then Sunny | 2 mph E | 0% |
| Tonight | 64°F | Mostly Clear | 2 mph E | 0% |
| Wednesday | 88°F | Mostly Sunny then Scattered Showers And Thunderstorms | 5 mph S | 50% |
| Wednesday Night | 67°F | Scattered Showers And Thunderstorms | 2 mph S | 50% |
| Thursday | 87°F | Showers And Thunderstorms Likely | 1 to 6 mph SW | 55% |
| Thursday Night | 67°F | Showers And Thunderstorms Likely | 0 to 5 mph SW | 57% |
| Friday | 85°F | Showers And Thunderstorms | 1 to 6 mph SW | 82% |
| Friday Night | 65°F | Showers And Thunderstorms then Chance Showers And Thunderstorms | 1 to 5 mph SW | 82% |
| Saturday | 85°F | Chance Showers And Thunderstorms | 2 to 7 mph SW | 36% |
| Saturday Night | 65°F | Chance Showers And Thunderstorms | 5 mph SW | 36% |
| Sunday | 88°F | Slight Chance Rain Showers then Slight Chance Showers And Thunderstorms | 2 to 8 mph SW | 20% |
| Sunday Night | 68°F | Chance Showers And Thunderstorms | 6 mph SW | 26% |
| Monday | 88°F | Chance Rain Showers | 5 to 9 mph SW | 39% |
| Monday Night | 66°F | Chance Showers And Thunderstorms | 2 to 7 mph SW | 48% |
Forecast source: National Weather Service (api.weather.gov) for New Castle Northwest (41.022, -80.356). Updated through the day.
Growing snapshot for New Castle Northwest
Last spring frost
Apr 30
First fall frost
Oct 23
Growing season
175 days
Hardiness zone
6a
More local growing data for New Castle Northwest: nearby ZIP 16105 weather · frost dates · planting calendar · Pennsylvania frost dates
Nearby towns & communities
Bessemer
Chewton
Edinburg
Ellport
Ellwood City
Enon Valley
Frisco
Frizzleburg
Hillsville
Mount Jackson
New Beaver
New Bedford
New Castle
New Galilee
New Wilmington
Oakland
Oakwood
Pulaski
S.N.P.J.
South New Castle
Volant
Wampum
West Pittsburg
Wurtemburg
Climate data from the nearest NOAA station, New Castle 1 N, Pa (2.8 mi from New Castle Northwest). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.