Frost Dates for 16841 — Howard, Pennsylvania

Half of springs at Millheim, PA see their last 32°F night by May 5; only one in ten is past it by April 22, and one in ten still has one after May 24. Planting tender crops after May 14 leaves a 30% risk of a frost on them, after May 19 20%, and after May 24 10%. The 19 days between the even-odds date and the one-in-ten date is wider than at 90% of the 176 Pennsylvania stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 6 in half of years, as early as September 25 one year in ten, and holds off past October 21 one year in ten. A hard freeze of 28°F follows 12 days later, around October 18; in spring the one-in-ten date for 28°F is May 13, 11 days before the 32°F one. The freeze-free season lasts 153 days in a typical year, shorter than at 85% of the 176 Pennsylvania stations; it reaches 175 days one year in ten and falls short of 132 one year in ten. On average 152 nights a year drop to 32°F or below. Nights of 36°F, when frost can still settle on leaves in low, open spots, continue 14 days longer, to about May 19, and return around September 27. Severe cold of 16°F or below comes every winter, usually between November 26 and March 21.

July is the warmest month at Millheim, PA, averaging 84°F by day and 58°F at night; January is the coldest at 32°F and 15°F. A freezing night is all but certain in every month from October to April (a 90% chance or more). From June to August the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 63% of years.

Warmth for growing adds up to 2,568 growing degree days a year (base 50°F), fewer than at 74% of the 176 Pennsylvania stations. 34% of them (867) have built up by the end of June, and July adds the most, 656. Precipitation totals 42.4 inches a year, most in September (4.4") and least in February (2.3"); May to September bring 48% of it.

The nearest other station, Lock Haven Sewage Plt, PA, 14 miles northeast of Howard and 554 feet lower, has a last frost 5 days earlier (April 30), a first frost 14 days later (October 20), a season 20 days longer.

The first measurable snow (0.1 inch or more) in Howard usually arrives around November 28, and the last of the season around March 24. Those are the middle dates across the winters of 1991–2020 at Millheim, PA, 13.9 miles away: half of years saw snow earlier, half later. Every one of those winters saw snow. The last 32°F night of spring typically comes 42 days after the last snow.

ZIP 16841 is 14 miles from Millheim, PA, which stands at 1,120 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 16841 in zone 6b, the band where the coldest night of the year averaged -5 to 0°F (-20.6 to -17.8°C) over 1991–2020; a zone describes winter lows, not frost dates.