Historical weather data, all-time temperature records, and monthly climate averages for New Castle, IN. Explore typical weather conditions by week for trip planning, and see how today compares to the historical record.
April 5 in New Castle splits the difference between winter and spring — historically, you're looking at a 55° high and 34° low, with nearly a coin-flip chance of rain. The date has seen a wild 65-degree swing across the record books, from a balmy 80° in 1986 down to a bitter 15° in 1995.
New Castle doesn't do things halfway — its all-time records span from a scorching 107° in June 2012 to a brutal -26° in January 1994, a 133-degree range that captures Indiana's unforgiving climate extremes. A single July day in 1992 dumped 4.15 inches of rain, and a December 2004 snowstorm buried the area under a foot of snow in one shot.
New Castle is warmest mid-July, when average highs peak around 84-85°, and coolest in mid-January, when you're lucky to crack 33°. If you're trying to dodge rain, avoid early-to-mid June — it's the wettest stretch of the year, averaging over an inch of precipitation per week. Spring and fall offer the most comfortable temps, with April and October both hovering in the pleasant 61-65° range.