Annex, OR climate
Annex has chilly winters and hot summers, with very little rain. A typical July afternoon reaches 94°, a January night drops to 23°, and about 15 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Annex feels like
Winter
Spring
Summer
Fall
Annex weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | 30-yr range |
|---|---|---|---|---|---|---|
| January | 37° | 23° | 1.6" | 6.1" | 11 | 18° – 36° |
| February | 45° | 26° | 1.1" | 2.3" | 8 | 26° – 43° |
| March | 57° | 33° | 1.1" | 0.5" | 11 | 40° – 50° |
| April | 65° | 37° | 1.0" | 0 | 9 | 46° – 57° |
| May | 75° | 46° | 1.3" | 0 | 8 | 53° – 66° |
| June | 83° | 53° | 0.9" | 0 | 6 | 63° – 76° |
| July | 94° | 60° | 0.3" | 0 | 2 | 66° – 82° |
| August | 92° | 57° | 0.2" | 0 | 3 | 68° – 77° |
| September | 81° | 48° | 0.4" | 0 | 3 | 61° – 68° |
| October | 66° | 37° | 0.8" | 0 | 7 | 44° – 58° |
| November | 49° | 28° | 1.3" | 1.1" | 10 | 32° – 45° |
| December | 38° | 23° | 1.9" | 5.4" | 11 | 21° – 36° |
| Year | 65° | 39° | 11.8" | 15.4" | 91 |
“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 Annex
Annex gets 12 inches of rain and melted snow a year. December is the wettest month and August the driest. Rain or snow falls on about 91 days a year.
About 174 frost-free days a year
In half of years the last 32° night comes by April 23 and the first one by October 13. That leaves about 174 frost-free days for gardens, shorter than 56% of U.S. towns.
Heating and cooling a home in Annex
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Annex, 85% of that work is heating and 15% 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 Annex 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 Annex averaged 1.4° warmer than the 1900s. The biggest change is in January (+3.0°). The shift is larger than in 64% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Annex’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. January swings the most: between 1991 and 2020 its average temperature ranged from 18° to 36°. September is the most reliable, staying within 8°.
Common questions about Annex’s climate
What is the coldest month in Annex?
January, with a typical high of 37° and a low of 23°.
What is the hottest month in Annex?
July, with a typical high of 94° and a low of 60°. About 59 days a year reach 90°.
How much snow does Annex get?
About 15 inches in a normal winter, most of it in January.
When is the first frost in Annex?
In half of years the first 32° night comes by October 13, and the last spring frost by April 23.
What is the rainiest month in Annex?
December, with 1.9 inches of rain and melted snow. The year totals 12 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Annex itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Malheur Branch Exp Stn, OR (18 mi, snow) and Weiser, ID (1 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.