Millheim, Pennsylvania climate: Normal weather by month, frost dates and records
Millheim's normal year runs from 15°F January nights to 84°F July afternoons, with 42.4 inches of precipitation and 35 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 8.9°C, January lows of −10°C, July highs of 29°C, 1,078 mm of precipitation a year.
- NOAA stationMillheim
- Station IDUSC00365790
- Location40.88°N 77.47°W
- Elevation1,120 ft (341 m)
- From the centerunder 1 mile
- Population833
On October 23, the normal high in Millheim is 58°F and the normal low 35°F, and the chance of measurable rain or snow is 35%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Millheim.
- Jan 32° 15°
- Feb 37° 17°
- Mar 46° 25°
- Apr 60° 35°
- May 71° 45°
- Jun 79° 55°
- Jul 84° 58°
- Aug 82° 56°
- Sep 74° 49°
- Oct 62° 38°
- Nov 48° 29°
- Dec 38° 22°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like in Millheim each month?
July is the warmest month, with normal highs of 84°F; January the coldest, with normal lows of 15°F. The most precipitation falls in September (4.40 in), the least in February (2.32 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 32°F | 15°F | 23.5°F | 2.96 | 9.2 | 10 | <1 | 29 | 9 h 30 min |
| February | 37°F | 17°F | 27.0°F | 2.32 | 8.3 | 9 | <1 | 26 | 10 h 40 min |
| March | 46°F | 25°F | 35.2°F | 3.33 | 8.2 | 11 | <1 | 25 | 11 h 50 min |
| April | 60°F | 35°F | 47.2°F | 3.63 | 1.0 | 12 | <1 | 12 | 13 h 20 min |
| May | 71°F | 45°F | 58.0°F | 3.89 | 0.0 | 13 | <1 | 2 | 14 h 30 min |
| June | 79°F | 55°F | 67.0°F | 4.03 | 0.0 | 13 | 2 | <1 | 15 h 10 min |
| July | 84°F | 58°F | 71.2°F | 3.92 | 0.0 | 12 | 6 | <1 | 14 h 50 min |
| August | 82°F | 56°F | 69.0°F | 4.03 | 0.0 | 10 | 2 | <1 | 13 h 50 min |
| September | 74°F | 49°F | 61.4°F | 4.40 | 0.0 | 10 | 1 | 1 | 12 h 30 min |
| October | 62°F | 38°F | 49.7°F | 3.65 | 0.3 | 11 | <1 | 8 | 11 h 10 min |
| November | 48°F | 29°F | 38.5°F | 3.08 | 2.2 | 9 | <1 | 21 | 10 h |
| December | 38°F | 22°F | 29.8°F | 3.20 | 6.1 | 10 | <1 | 27 | 9 h 20 min |
| Year (annual) | 59°F | 37°F | 48.1°F | 42.44 | 35.3 | 130 | 11 | 152 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 0°C | −10°C | −4.7°C | 75 mm | 23 cm |
| February | 3°C | −8°C | −2.8°C | 59 mm | 21 cm |
| March | 8°C | −4°C | 1.8°C | 85 mm | 21 cm |
| April | 15°C | 2°C | 8.4°C | 92 mm | 3 cm |
| May | 22°C | 7°C | 14.4°C | 99 mm | 0 cm |
| June | 26°C | 13°C | 19.4°C | 102 mm | 0 cm |
| July | 29°C | 15°C | 21.8°C | 100 mm | 0 cm |
| August | 28°C | 13°C | 20.6°C | 102 mm | 0 cm |
| September | 23°C | 9°C | 16.3°C | 112 mm | 0 cm |
| October | 16°C | 3°C | 9.8°C | 93 mm | 1 cm |
| November | 9°C | −2°C | 3.6°C | 78 mm | 6 cm |
| December | 3°C | −6°C | −1.2°C | 81 mm | 15 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00365790; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
When is the best weather to visit Millheim?
Normal highs sit between 65°F and 85°F in May, June, July, August and September. Of those, September has the fewest days with rain (10).
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00365790.
When is the last frost in Millheim?
In Millheim, the last spring frost (32°F) comes after May 5 in half of years and after May 24 in one year in ten; the first autumn frost comes before October 6 in half of years and before September 25 in one year in ten.
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- May 51 year in 10 after May 24; 9 in 10 after April 22
- First autumn frost, half of years before
- October 61 year in 10 before September 25; 9 in 10 before October 21
NOAA puts the median frost-free season at 153 days, and the season without a hard freeze (28°F) at 176 days.
A hard freeze (28°F) comes after April 24 in half of springs and before October 18 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Millheim in zone 6b in ZIP code 16854. By the map's own method, the average of each year's coldest night over 1991-2020, Millheim's NOAA station is in zone 6b: the coldest night of a typical year reaches −5°F (20 complete years).
Frost dates for every NOAA station in Pennsylvania · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00365790; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; the station zone: ACIS daily lows, 1991-2020. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
How hot and how cold does it get in Millheim?
In a normal year in Millheim, 11 days a year reach 90°F, 152 nights fall to 32°F or colder and 130 days bring measurable precipitation.
- Days at 90°F or more
- 11a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 152a normal year
- Days that stay below freezing
- 42high of 32°F or less
- Days with 0.01 inch of precipitation
- 130a normal year
- Days with 1 inch of snow or more
- 12a normal year
Source: NOAA NCEI 1991-2020 annual normals, station USC00365790.
How sunny is Millheim?
Over a year 70% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Millheim, 3.8 kWh per square metre a day. July is the sunniest month (77%) and December the cloudiest (58%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 60% | 1.8 |
| February | 65% | 2.6 |
| March | 64% | 3.6 |
| April | 67% | 4.7 |
| May | 68% | 5.3 |
| June | 74% | 5.9 |
| July | 77% | 5.9 |
| August | 76% | 5.2 |
| September | 73% | 4.2 |
| October | 67% | 2.9 |
| November | 67% | 2.1 |
| December | 58% | 1.4 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How much heating and cooling does Millheim need?
A normal year in Millheim brings 6,659 heating degree days, 24% more than the median U.S. place (5,373), and 535 cooling degree days, 41% fewer than the median (908). Seven months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 2,568 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,288 | 0 |
| February | 1,064 | 0 |
| March | 925 | 0 |
| April | 536 | 2 |
| May | 244 | 26 |
| June | 52 | 112 |
| July | 9 | 200 |
| August | 22 | 146 |
| September | 154 | 46 |
| October | 478 | 4 |
| November | 794 | 0 |
| December | 1,093 | 0 |
| Year (annual) | 6,659 | 535 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00365790. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
Has Millheim been warmer than normal lately?
2025 averaged 49.3°F, 1.2°F above the 1991-2020 normal of 48.1°F. 2 of the 2 complete years since 2024 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2024 | 51.8°F | +3.7°F | 46.86 | 32.2 |
| 2025 | 49.3°F | +1.2°F | 41.43 | 21.5 |
Source: observed years: ACIS, station USC00365790. A year counts only with all twelve months complete.
How does Millheim's climate compare?
Millheim is warmer than 26 of the other 107 places with their own NOAA record in Pennsylvania, and wetter than 35. Across the 7,247 U.S. stations with normals, its annual mean of 48.1°F is warmer than 32%.
In the Köppen classification computed from these normals, Millheim is Dfb: continental, no dry season, warm summer. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Which places near Millheim share this climate record?
16 places have no NOAA station with 1991-2020 normals of their own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.
- Zion, PA2,173 people · 11 mi W
- Nittany, PA747 people · 9 mi NW
- Aaronsburg, PA706 people · 2 mi NE
- Howard, PA671 people · 13 mi NW
- Lamar, PA620 people · 9 mi N
- Spring Mills, PA478 people · 5 mi SW
- Rebersburg, PA470 people · 4 mi N
- Snydertown, PA437 people · 10 mi NW
- Mingoville, PA301 people · 10 mi W
- Tylersville, PA174 people · 7 mi N
- Potters Mills, PA155 people · 10 mi SW
- Madisonburg, PA130 people · 4 mi NW
- Coburn, PA127 people · 1 mi SE
- Woodward, PA123 people · 7 mi E
- Jacksonville, PA53 people · 11 mi NW
- Hublersburg, PA46 people · 9 mi NW
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
Questions about Millheim's climate
What is the coldest month in Millheim?
January, with a normal high of 32°F and a normal low of 15°F. The warmest is July (84°F by day, 58°F at night).
Does it snow in Millheim?
Yes: 35 inches in a normal year, falling on 15 days with 0.1 inch or more, the most in January (9.2 inches).
What is the rainiest month in Millheim?
September, with 4.40 in of precipitation in a normal year; the driest is February with 2.32 in.
What plant hardiness zone is Millheim in?
The USDA's 2023 map puts Millheim in zone 6b in ZIP code 16854. By the same method at Millheim's NOAA station, the coldest night of a typical year reaches −5°F (20 years, 1991-2020): zone 6b.
How late can frost come in Millheim?
In half of years the last 32°F night comes after May 5; in one year in ten it comes after May 24. Waiting until May 24 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Pennsylvania climateThe statewide normals and every place in the state
- Laurelton, PA14 miles from this station, 51.8°F a year
- Lock Haven, PA17 miles from this station, 50.3°F a year
- Lewistown, PA21 miles from this station, 51.9°F a year
- State College, PA22 miles from this station, 50.1°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made