Weather without surprises: Sylvan Hills keeps close to the norm for U.S. towns
The warmest part of a July day comes in at 85° on average. Seasons differ by 65°, from the coldest nights to the warmest afternoons. By precipitation alone, it ranks drier than 61% of U.S. towns. The heating season runs November to March: each of those months averages under 50°.
A year in Sylvan Hills at a glance
Each month’s typical high and low, and what it brings.
What stands out about Sylvan Hills’ climate
Compared with towns across the U.S., with Sylvan Hills’ place in Pennsylvania beside it.
What a year in Sylvan Hills feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 176 frost-free days a year
In half of years the last 32° night comes by April 25 and the first by October 21. Frost and day counts come from NOAA’s station at Altoona 3 W, PA, 5 miles from the town’s center, 100 ft higher.
The 2023 USDA map puts Sylvan Hills’ center in zone 6b: the coldest night of a typical winter, averaged over 1991–2020, reaches about −1°. Plant labels use the zone; frost dates tell you when to plant.
Freezing nights by month
Average nights at or below 32°
90° days by month
Average days at 90° or more
About 26 inches of snow a winter
Snow, measured at Williamsburg, PA, is heaviest from January through February, about 7 inches a month. Precipitation (rain plus melted snow) adds up to 40 inches a year; May is the wettest month and February the driest. Rain or snow falls on about 136 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Sylvan Hills
91% of the work is heating, so the furnace matters far more than the air conditioner. Months averaging under 55° run from October through April.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Altoona 3 W, PA.
Living with Sylvan Hills’ climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
176 frost-free days in zone 6b. The last frost comes by Apr 25 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Oct 21.
Months with highs of 62–84° and lows of 40° or more: May, June, August, September and October.
Parks & trails →Of the yearly building losses FEMA expects in Sylvan Hills from natural hazards, river flooding is the largest share (83%); heat waves, cold waves, winter storms and ice storms together are 4%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Sylvan Hills and its neighbors
Every town next door is within a degree of Sylvan Hills in January and July, closer than the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Sylvan Hills’, farther away
TownRatings’ own comparison of NOAA 1991–2020 normals, not a NOAA product: places of 5,000+ at least 150 miles away, one per state, closest on January low, July high, precipitation and snow.
| Town | Jan. low | July high | Precip. | Snow |
|---|---|---|---|---|
| Sylvan Hills, PA | 20° | 85° | 40" | 26" |
| Dublin, OH | 21° | 85° | 40" | 24" |
| Marion, IN | 19° | 84° | 41" | 25" |
| Springfield, IL | 19° | 86° | 39" | 22" |
| Keokuk, IA | 18° | 86° | 40" | 23" |
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value. Snow and frost-free days come from the nearest weather station, so neighbors often share them.
Warmer than it used to be
The last 30 years in Sylvan Hills averaged 1.2° warmer than the 1900s. The biggest change is in December (+2.2°).
A smaller shift than in 66% of U.S. towns.
Change by month
The two periods overlap (1991–2000 is in both), which makes the gap a little smaller than it would be between separate periods.
How Sylvan Hills compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Sylvan Hills’ place among Pennsylvania’s.
Sylvan Hills weather by month
Highs, lows and precipitation from NOAA’s grid at Sylvan Hills’ center; snow, wet days and snow on the ground from Williamsburg, PA. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 37° | 20° | 2.6" | 7.5" | 11 | 13 | 20° – 37° |
| February | 41° | 21° | 2.3" | 6.8" | 10 | 12 | 19° – 39° |
| March | 50° | 27° | 3.2" | 4.8" | 11 | 5 | 32° – 50° |
| April | 63° | 38° | 3.5" | 0.2" | 13 | 0 | 45° – 56° |
| May | 73° | 47° | 3.9" | 0.0" | 14 | 0 | 54° – 67° |
| June | 81° | 56° | 3.9" | 0.0" | 12 | 0 | 64° – 71° |
| July | 85° | 60° | 3.8" | 0.0" | 11 | 0 | 68° – 77° |
| August | 83° | 59° | 3.6" | 0.0" | 11 | 0 | 67° – 75° |
| September | 76° | 52° | 3.9" | 0.0" | 10 | 0 | 61° – 68° |
| October | 64° | 40° | 3.2" | 0.0" | 11 | 0 | 49° – 59° |
| November | 52° | 32° | 3.0" | 1.3" | 10 | 1 | 36° – 48° |
| December | 41° | 25° | 3.0" | 5.1" | 11 | 7 | 23° – 43° |
| Year | 62° | 40° | 39.9" | 25.7" | 136 | 37 |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 19° to 39°. June is the most reliable, staying within 7°.
Where Sylvan Hills’ numbers come from
Normals are 30-year averages, not a forecast. How TownRatings reads climate data →
- Temperatures and precipitation: NOAA’s gridded 1991–2020 normals for the 5 km cell at Sylvan Hills’ center.
- Snow: Williamsburg, PA.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Altoona 3 W, PA, 5 miles from the town’s center, 100 ft higher; the nearest station that passes our checks for distance, height and agreement with the grid.
- Growing zone: USDA Plant Hardiness Zone Map, 2023. USDA Agricultural Research Service and PRISM Group, Oregon State University, prism.oregonstate.edu/phzm, accessed 8 Oct 2026.
- Then and now: NOAA’s gridded normals for 1901–2000 at the same cell.
- Storms and extremes: FEMA National Risk Index (expected annual losses to buildings).
Common questions about Sylvan Hills’ climate
What is the weather like in Sylvan Hills?
A typical July afternoon reaches 85°, a January night drops to 20°, and about 26 inches of snow falls in a normal winter. Colder January nights than 59% of U.S. towns; cooler July afternoons than 50% of U.S. towns.
How cold does it get in Sylvan Hills in winter?
January nights average 20°. About 128 nights a year reach 32° or below and 3 reach 0° or below. In the coldest January of the last 30 years the month averaged 20°.
How much snow does Sylvan Hills get?
About 26 inches in a normal winter at Williamsburg, PA, heaviest from January through February, about 7 inches a month, with snow on the ground about 37 days a year.
How hot does it get in Sylvan Hills?
July, with a typical high of 85° and a low of 60°. About 6 days a year reach 90° (Altoona 3 W, PA).
When is the first and last frost in Sylvan Hills?
In half of years the last spring frost (32°) comes by April 25 and the first fall frost by October 21, about 176 frost-free days, at Altoona 3 W, PA.
What growing zone is Sylvan Hills in?
Zone 6b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −1°.
What is the best time of year to visit Sylvan Hills?
By one simple rule (highs of 62–84° and lows of 40° or more), May, June, August, September and October. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Sylvan Hills getting warmer?
Yes: 1991–2020 averaged 1.2° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 66% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Sylvan Hills.
Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000; USDA/PRISM 2023 hardiness zones; FEMA National Risk Index. Today’s forecast: National Weather Service.