Historical weather data, all-time temperature records, and monthly climate averages for Mount Lebanon, PA. Explore typical weather conditions by week for trip planning, and see how today compares to the historical record.
April 5 in Mount Lebanon runs mild, with average highs near 57° and lows around 37°. The date has a wild range in the record books though — as recently as 2023 it hit 86°, and in 2016 it dropped to 22°. Rain is possible (about a 1-in-3 shot), but snow is off the table.
Mount Lebanon's weather has some serious extremes on its résumé — a scorching 102° in July 1936 and a brutal -16° just six months later that same year. On the wet side, a single day in September 2004 dropped 6 inches of rain, and a November storm in 1950 buried the area under 12 inches of snow.
Summer is the sweet spot here, with highs peaking around 84° the week of July 9–15 — ideal for being outside. Winter bites hardest in mid-January, when average highs barely reach 35°. If you're trying to dodge rain, avoid mid-June, which is the wettest stretch of the year at over an inch of precip per week.