4-Inch Soil Temperature in Pennsylvania
The current average 4-inch soil temperature across Pennsylvania is 73°F, measured at 2 USDA and NOAA monitoring stations. Readings range from 72°F to 73°F. Soil across Pennsylvania is running 2°F below the seasonal normal of 75°F for mid-August, based on 2 of 2 stations with historical records. Last updated August 16, 2026.
Why the 4-Inch Reading
Every reading here is measured at native 4-inch depth by USDA SCAN (Soil Climate Analysis Network) and NOAA USCRN (US Climate Reference Network) stations — not modeled. The 4-inch root-zone temperature changes more slowly than the surface, making it the steadier signal for established-lawn and garden timing: pre-emergent and broadleaf herbicide windows, fertilizer applications, and core aeration.
Stations Measuring 4-Inch Depth in Pennsylvania (2)
| Station | 4" Temp | Last Reading |
|---|---|---|
| Mahantango Ck (Northumberland) | 72°F | 2026-08-16 |
| Rock Springs Pa (Centre) | 73°F | 2026-08-16 |
Cities in Pennsylvania (72)
4-Inch Soil Temperature FAQ for Pennsylvania
What is the current 4-inch soil temperature in Pennsylvania?
The current average 4-inch soil temperature across Pennsylvania is 73°F, measured at 2 USDA and NOAA stations. Readings range from 72°F to 73°F depending on location and elevation. Soil across Pennsylvania is running 2°F below the seasonal normal of 75°F for mid-August, based on 2 of 2 stations with historical records.
What does the 4 inch soil temperature mean?
The 4 inch soil temperature shows conditions deeper in the root zone than the 2 inch germination reading. It is commonly used for established lawn, garden, and agricultural timing because it changes more slowly than the surface layer, so it is a steadier signal for fertilizer, aeration, and weed-control decisions.
Why use 4-inch soil temperature instead of 2-inch?
Use 2 inches for germination decisions, since that is where seeds sit. Use the 4 inch soil temperature for established lawn and garden timing: it reads the root zone, changes more slowly than the surface, and is the depth most fertilizer, aeration, and disease guidance references.
See the national 4-inch soil temperature map, the full Pennsylvania soil temperature directory (all depths), or the live national soil temperature map.