Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated

Planting zone for 16865 — Pennsylvania Furnace, PA

ZIP code 16865 (Pennsylvania Furnace, Centre County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is April 20 and the first fall frost October 26.

Where ZIP 16865 is

Outlined: the ZIP code area · tap the map for the zone at any spot · scroll or pinch to zoom

Not the official USDA Plant Hardiness Zone Map. Zones come from the 2023 USDA hardiness-zone data by the PRISM Group, Oregon State University; we re-mapped and recolored them. The official map is at planthardiness.ars.usda.gov.

Zone6b−5 to 0 °F
Coldest night−20.6 to −17.8 °C
Last frostApr 20
First frostOct 26
2012 zone6b

Same zone as on the 2012 map. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 6b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Pennsylvania Furnace, PA…

Forecast data: National Weather Service (api.weather.gov), public domain. This is not a warning service — for official frost and freeze warnings see weather.gov.

Frost dates in Pennsylvania Furnace, PA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 20median — 50% chance of a later frost
Safe for tender plantsMay 6only 10% chance of frost after
First fall frostOctober 26median — 10% chance by Oct 10
Growing season187 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 8 and returns around November 5.

From the NOAA station State College, PA — 7 miles away, elevation 1,171 ft. NOAA NCEI U.S. Climate Normals 1991–2020, 32 °F threshold. Low spots and valleys can freeze later in spring than the station.

When to plant vegetables in 16865

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 9 – Mar 23
SpinachSow outdoors · Mar 9 – Mar 30
Broccoli, cabbageStart indoors · Feb 9 – Feb 23
Broccoli, cabbageTransplant · Mar 30 – Apr 13
Onion setsPlant outdoors · Mar 23 – Apr 6
PotatoesPlant outdoors · Mar 30 – Apr 13
LettuceSow outdoors · Mar 23 – Apr 6
Carrots, beetsSow outdoors · Mar 30 – Apr 13
TomatoesStart indoors · Feb 23 – Mar 9
TomatoesTransplant · Apr 27 – May 11
Peppers, eggplantStart indoors · Feb 9 – Feb 23
Peppers, eggplantTransplant · May 4 – May 18
BeansSow outdoors · Apr 27 – May 11
Sweet cornSow outdoors · Apr 27 – May 11
Cucumbers, squashSow outdoors · Apr 27 – May 11
Fall lettuce, spinachSow outdoors · Aug 31 – Sep 14
GarlicPlant cloves · Oct 12 – Nov 16
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 20) and first fall frost (Oct 26) with the rules of thumb U.S. extension services publish. Cool-season crops take a light frost; warm-season crops do best once the soil is above about 60 °F.

When spring arrived in 2026

In 2026, spring leaf-out near 16865 came on Mar 31 — 6 days earlier than the 1991–2020 average (Apr 6).

JanFebMarAprMayJun

The Spring Index marks the day when accumulated warmth is enough for lilac and honeysuckle to leaf out — a widely used signal that the growing season has started. Source: USA National Phenology Network, www.usanpn.org — Spring Indices, first leaf, 2026 (data as of 2026-09-08) and 30-year average 1991–2020 (CC BY 4.0).

Soil in Pennsylvania Furnace, PA

The soil mapped at the center of ZIP 16865 is Hagerstown — silt loam, well drained.

TextureSilt loama good balance for most vegetables
pH6.0slightly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter3%moderate
Hydrologic groupBwater soaks in moderately
Farmland classprime farmlandUSDA classification

Map unit: Hagerstown silt loam, 0 to 3 percent slopes.

Soil Survey Staff, Natural Resources Conservation Service, USDA. Soil Survey Geographic (SSURGO) Database, via Soil Data Access, accessed 2026-10-29. The soil at the center point of ZIP 16865; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Pennsylvania Furnace, PA

Summer high81 °Faverage high, July
Winter low21 °Faverage low, January
Hot days6days a year at 90 °F or more
Freezing nights122nights a year at 32 °F or less
Growing degree days2,874base 50 °F — the season’s usable heat
Longest day15 h 06 mindaylight on June 21
Shortest day9 h 15 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation43.8 inper year, rain and melted snow

Average high and low, by month

10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 34 °F, low 21 °F 34°21° JanFebruary: average high 37 °F, low 22 °F 37°22° FebMarch: average high 46 °F, low 28 °F 46°28° MarApril: average high 59 °F, low 39 °F 59°39° AprMay: average high 69 °F, low 50 °F 69°50° MayJune: average high 77 °F, low 59 °F 77°59° JunJuly: average high 81 °F, low 63 °F 81°63° JulAugust: average high 79 °F, low 62 °F 79°62° AugSeptember: average high 72 °F, low 54 °F 72°54° SepOctober: average high 61 °F, low 43 °F 61°43° OctNovember: average high 49 °F, low 34 °F 49°34° NovDecember: average high 38 °F, low 26 °F 38°26° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 3.22 in precipitation 3.2 JanFebruary: 2.66 in precipitation 2.7 FebMarch: 3.67 in precipitation 3.7 MarApril: 3.29 in precipitation 3.3 AprMay: 4.04 in precipitation 4.0 MayJune: 4.39 in precipitation 4.4 JunJuly: 3.85 in precipitation 3.9 JulAugust: 3.68 in precipitation 3.7 AugSeptember: 4.45 in precipitation 4.5 SepOctober: 3.90 in precipitation 3.9 OctNovember: 3.32 in precipitation 3.3 NovDecember: 3.31 in precipitation 3.3 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: State College, PA (7 mi away); precipitation: Port Matilda 2.2 Ese, PA (6 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6b.

168686b
Pine Grove Mills, PA · 3 mi
166696b
Petersburg, PA · 5 mi
168776b
Warriors Mark, PA · 6 mi
168036b
State College, PA · 7 mi
168046b
State College, PA · 7 mi
168056b
State College, PA · 7 mi
168026b
University Park, PA · 7 mi
166836b
Spruce Creek, PA · 7 mi

Pennsylvania planting zones →

Questions about 16865

What planting zone is ZIP code 16865?

ZIP code 16865 (Pennsylvania Furnace, PA) is in USDA hardiness zone 6b on the 2023 map: the coldest night of an average winter reaches −5 to 0 °F (−20.6 to −17.8 °C).

When is the last frost in Pennsylvania Furnace, PA?

The median last spring frost (32 °F) near 16865 is April 20; after May 6 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, State College station.

When is the first frost in Pennsylvania Furnace, PA?

The median first fall frost near 16865 is October 26, giving a median frost-free growing season of 187 days.

When should I plant tomatoes in 16865?

Start tomato seeds indoors around Feb 23 – Mar 9 and set transplants outside around Apr 27 – May 11, one to three weeks after the median last frost.

How much rain and snow does 16865 get?

About 43.8 inches of precipitation a year (NOAA 1991–2020 normals, Port Matilda 2.2 Ese station).

How hot do summers get in Pennsylvania Furnace, PA?

The average high peaks at 81 °F in July, with about 6 days a year at 90 °F or more.

What kind of soil does 16865 have?

The USDA soil survey maps Hagerstown at the center of ZIP 16865: silt loam, well drained, pH about 6.0 (slightly acidic).

Did spring come early in Pennsylvania Furnace, PA in 2026?

Spring leaf-out near 16865 came on Mar 31 in 2026, 6 days earlier than the 1991–2020 average (Apr 6), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Pennsylvania Furnace, PA?

Long-day onions: the longest day near 16865 is 15 h 06 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).