Weather conditions at John Day Fossil Beds National Monument are highly variable in this semi-arid desert landscape. Summer highs can climb into the 110's. Winters tend to be fairly mild, with occasional snow and ice and lows seldom dipping below zero.
See the table below for a list average monthly temperatures in the town of Dayville, OR (the town closest to the Sheeprock Unit) between 1991 and 2020. Please note, these are only averages and do not represent the extreme temperatures the park can reach during the summer, nor does it represent snowfall.
Average monthly temperatures and precipitation for Dayville, OR
| |
Average High (Fahrenheit) |
Average Low (Fahrenheit) |
Total Precipitation (inches) |
| January |
45° |
29° |
1.12 |
| February |
50° |
29° |
0.85 |
| March |
58° |
33° |
1.27 |
| April |
63° |
37° |
1.38 |
| May |
73° |
44° |
1.95 |
| June |
81° |
49° |
1.38 |
| July |
93° |
55° |
0.53 |
| August |
92° |
53° |
0.54 |
| September |
82° |
47° |
0.56 |
| October |
67° |
39° |
1.09 |
| November |
54° |
33° |
1.32 |
| December |
46° |
27° |
1.14 |
View local data from the park's weather station.
