Frost dates for State College, Pennsylvania
Half of years have their last spring frost by April 20, but 1 year in 10 still frosts after May 6.
A frost date is really a percentile from 30 years of records at a nearby weather station: in about half of years a frost still comes after the median date. Both numbers are below, so you can choose the risk yourself.
The odds
Last spring frost
How often a frost still comes on or after each date.
- 1 year in 10
- May 6
- 1 year in 5
- May 1
- 3 years in 10
- April 27
- 2 years in 5
- April 23
- Half of years (the median)
- April 20
First fall freeze
How often the first freeze comes on or before each date.
- 1 year in 10
- October 10
- 1 year in 5
- October 17
- 3 years in 10
- October 20
- 2 years in 5
- October 23
- Half of years (the median)
- October 26
- Growing season
- about 187 days
- Hardiness zone nearby
- 6b
- Summer days
- a usual high of about 26 °C79 °F
- Lettuce and spinach run to seed
- June to August, in hot, long days (how we know)
Summer and rain
A growing garden needs about 25 mm1 in of water a week, rain and watering together. Here is what a normal month brings.
Month by month
- January
- high ~1 °C34 °F · low ~-6 °C20 °F · rain ~74 mm2.9 in
- February
- high ~3 °C37 °F · low ~-6 °C22 °F · rain ~62 mm2.5 in
- March
- high ~8 °C46 °F · low ~-2 °C28 °F · rain ~86 mm3.4 in
- April
- high ~15 °C59 °F · low ~4 °C39 °F · rain ~89 mm3.5 in
- May
- high ~21 °C69 °F · low ~10 °C50 °F · rain ~92 mm3.6 in
- June
- high ~25 °C77 °F · low ~15 °C59 °F · rain ~104 mm4.1 in
- July
- high ~27 °C81 °F · low ~17 °C63 °F · rain ~96 mm3.8 in
- August
- high ~26 °C79 °F · low ~16 °C62 °F · rain ~106 mm4.2 in
- September
- high ~22 °C72 °F · low ~12 °C54 °F · rain ~100 mm3.9 in
- October
- high ~16 °C61 °F · low ~6 °C43 °F · rain ~88 mm3.5 in
- November
- high ~9 °C49 °F · low ~1 °C33 °F · rain ~76 mm3 in
- December
- high ~4 °C38 °F · low ~-3 °C26 °F · rain ~81 mm3.2 in
Where these numbers come from
NOAA NCEI 1991–2020 Climate Normals, the State College station (listed by NOAA as State College HCN, USC00368449), at 40.79, -77.87. These are that station’s own records, unshifted. The further your garden is from it, the less exactly they describe your ground. The planner finds the nearest station to your garden and lowers its confidence with distance, so no number is presented as if it were measured in your garden.
Cold air also pools in low ground on the clear, still nights when frost happens, so a hollow can freeze while a slope a few hundred feet away does not. No table can know that about your garden. A few seasons of your own logged frosts can.
ZIP codes nearest this station
16652, 16669, 16683, 16801, 16802, 16803, 16823, 16827, 16828, 16835, 16844, 16851…
+3 moreShow fewer
16865, 16868, 16877.
Nearby stations
The nearest stations and how their last-frost dates compare. Together they show how frost varies across your area.
- Philipsburg 2 S, PA, last frost by May 13
- Prince Gallitzin State Park, PA, last frost by May 10
- Altoona Blair County Airport, PA, last frost by April 23
- Selinsgrove 2 S, PA, last frost by April 25
- Carlisle Wtp, PA, last frost by April 23
- Shippensburg, PA, last frost by April 19
Other stations in Pennsylvania.
- Johnstown Cambria County Airport, PA, last frost by April 29
- Middletown Harrisburg International Airport, PA, last frost by April 9
- Putneyville 2 SE Dam, PA, last frost by May 10
- Mahanoy City 2 N, PA, last frost by April 30
- Lancaster Airport, PA, last frost by April 18
- Schenley Lock, PA, last frost by April 21
- Confluence 1 SW Dam, PA, last frost by April 30
- Mckeesport, PA, last frost by May 2
When do I plant? · Where the dates come from
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