Harrisburg, OR climate
Harrisburg has mild winters and pleasant summers. A typical July afternoon reaches 83°, a January night drops to 36°.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Harrisburg feels like
Winter
Spring
Summer
Fall
Harrisburg weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | 30-yr range |
|---|---|---|---|---|
| January | 48° | 36° | 6.4" | 36° – 46° |
| February | 52° | 36° | 4.9" | 37° – 49° |
| March | 57° | 38° | 5.1" | 44° – 53° |
| April | 62° | 40° | 3.7" | 47° – 56° |
| May | 69° | 45° | 2.7" | 52° – 62° |
| June | 74° | 49° | 1.5" | 58° – 68° |
| July | 83° | 52° | 0.4" | 62° – 71° |
| August | 84° | 52° | 0.4" | 65° – 72° |
| September | 77° | 49° | 1.5" | 60° – 66° |
| October | 65° | 43° | 3.6" | 50° – 59° |
| November | 53° | 39° | 6.4" | 41° – 51° |
| December | 47° | 35° | 7.5" | 36° – 44° |
| Year | 64° | 43° | 44.0" |
“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.
Rain and snow in Harrisburg
Harrisburg gets 44 inches of rain and melted snow a year. December is the wettest month and July the driest.
About 196 frost-free days a year
In half of years the last 32° night comes by April 11 and the first one by October 23. That leaves about 196 frost-free days for gardens, longer than 70% of U.S. towns.
Heating and cooling a home in Harrisburg
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Harrisburg, 94% of that work is heating and 6% is cooling, so the furnace matters far more than the air conditioner.
Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.
How Harrisburg compares
Compared with every U.S. town and city on TownTapestry, each counted once.
Warmer than it used to be
The last 30 years in Harrisburg averaged 1.1° warmer than the 1900s. The biggest change is in January (+2.5°). The shift is smaller than in 62% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Harrisburg’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. February swings the most: between 1991 and 2020 its average temperature ranged from 37° to 49°. September is the most reliable, staying within 6°.
Common questions about Harrisburg’s climate
What is the coldest month in Harrisburg?
December, with a typical high of 47° and a low of 35°.
What is the hottest month in Harrisburg?
August, with a typical high of 84° and a low of 52°. About 18 days a year reach 90°.
When is the first frost in Harrisburg?
In half of years the first 32° night comes by October 23, and the last spring frost by April 11.
What is the rainiest month in Harrisburg?
December, with 7.5 inches of rain and melted snow. The year totals 44 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Harrisburg itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Eugene Mahlon Sweet Airport, OR (10 mi, frost, heat and degree days). Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.