Historical weather data, all-time temperature records, and monthly climate averages for Plum, PA. Explore typical weather conditions by week for trip planning, and see how today compares to the historical record.
April 4th in Plum sits right in that uncertain stretch of spring — the average high of 59° sounds pleasant, but this date has swung from a brutal 21° low in 2021 to a shirt-sleeve 76° high just two years ago in 2023. With a coin-flip 53% chance of rain, an umbrella is smart company. At least snow is off the table.
Plum's weather has real range — 116 degrees of it, to be exact, spanning from a scorching 102° in June 2022 down to a bone-cracking -14° in January 2026. The wettest single day on record dumped 6.88 inches during a September 2004 storm, and an early-season November blizzard in 1950 buried the area under 17 inches of snow.
Summer is the headliner here — the warmest week of the year runs July 2–8 with average highs of 86°, while January 15–21 bottoms out at a frigid 33°. If you're watching the calendar for rain, mid-June is the wettest stretch, averaging over an inch in a single week. Spring and fall offer the most comfortable shoulder seasons, with April and October both landing in the low 60s.