Best Time to Drive: Hermiston, OR to Keizer, OR

The best overall window to drive from Hermiston, OR to Keizer, OR is June to September. July is especially comfortable, and 7 AM to 10 AM is usually the easiest departure window. The main things to watch are heavy rain and ponding.

Best overall window

June to September

This stretch gives the steadiest mix of comfort, daylight, and lower weather friction.

Easiest departure pattern

7 AM to 10 AM

This is short enough that a mid-morning departure still keeps the whole drive comfortable.

Most challenging stretch

January to March

November is one of the harder months for this route because the weather friction stacks up faster.

Why This Route Scores Differently

This is a same-day corridor, so departure timing matters almost as much as the month you choose.

The current best window is June to September, when the drive is more likely to feel steady end to end.

This score uses multiple NOAA sample points along the route instead of a single state-wide climate average.

Month-by-Month Driving Conditions

Jan

Difficult 27°F

Feb

Difficult 28°F

Mar

Challenging 31°F

Apr

Fair 35°F

May

Good 39°F

Jun

Great 42°F

Jul

Great 46°F

Aug

Great 46°F

Sep

Great 43°F

Oct

Challenging 37°F

Nov

Difficult 31°F

Dec

Difficult 27°F

Best Good/Fair Challenging

Average Conditions by Month

January

Avg high / low 30 / 24°F

Moisture 7.5 in rain

Rating Difficult

Best departure

7 AM to 10 AM

Storm-prone Winter mix risk

Temperatures are workable, but not as easy as the best shoulder-season windows.

Rain is common enough that extra buffer time makes sense.

February

Avg high / low 33 / 24°F

Moisture 5.6 in rain

Rating Difficult

Best departure

7 AM to 10 AM

Storm-prone Winter mix risk

Temperatures are workable, but not as easy as the best shoulder-season windows.

Rain is common enough that extra buffer time makes sense.

March

Avg high / low 37 / 26°F

Moisture 5.9 in rain

Rating Challenging

Best departure

7 AM to 10 AM

Storm-prone

Temperatures are workable, but not as easy as the best shoulder-season windows.

Rain is common enough that extra buffer time makes sense.

April

Avg high / low 40 / 29°F

Moisture 4.3 in rain

Rating Fair

Best departure

9 AM to 12 PM

Wet stretches

Temperatures are workable, but not as easy as the best shoulder-season windows.

Weather is mixed enough that departure timing still matters.

May

Avg high / low 45 / 32°F

Moisture 3 in rain

Rating Good

Best departure

9 AM to 12 PM

Steady driving window

Temperatures are workable, but not as easy as the best shoulder-season windows.

Weather is mixed enough that departure timing still matters.

June

Avg high / low 49 / 35°F

Moisture 2.1 in rain

Rating Great

Best departure

7 AM to 10 AM

Steady driving window

Temperatures are workable, but not as easy as the best shoulder-season windows.

Rain disruption is usually limited compared with wetter months.

July

Avg high / low 54 / 39°F

Moisture 0.5 in rain

Rating Great

Best departure

7 AM to 10 AM

Holiday traffic

Temperatures are workable, but not as easy as the best shoulder-season windows.

Rain disruption is usually limited compared with wetter months.

August

Avg high / low 54 / 39°F

Moisture 0.6 in rain

Rating Great

Best departure

7 AM to 10 AM

Steady driving window

Temperatures are workable, but not as easy as the best shoulder-season windows.

Rain disruption is usually limited compared with wetter months.

September

Avg high / low 50 / 36°F

Moisture 1.9 in rain

Rating Great

Best departure

7 AM to 10 AM

Steady driving window

Temperatures are workable, but not as easy as the best shoulder-season windows.

Rain disruption is usually limited compared with wetter months.

October

Avg high / low 42 / 31°F

Moisture 4.8 in rain

Rating Challenging

Best departure

9 AM to 12 PM

Wet stretches

Temperatures are workable, but not as easy as the best shoulder-season windows.

Weather is mixed enough that departure timing still matters.

November

Avg high / low 35 / 27°F

Moisture 8.1 in rain

Rating Difficult

Best departure

7 AM to 10 AM

Storm-prone Holiday traffic

Temperatures are workable, but not as easy as the best shoulder-season windows.

Rain is common enough that extra buffer time makes sense.

December

Avg high / low 30 / 24°F

Moisture 8.7 in rain

Rating Difficult

Best departure

7 AM to 10 AM

Storm-prone Winter mix risk Holiday traffic

Temperatures are workable, but not as easy as the best shoulder-season windows.

Rain is common enough that extra buffer time makes sense.

Seasonal Hazards on This Route

Heavy rain and ponding

Jan - Dec

Short intense downpours can make a same-day drive feel longer than the raw route time suggests.

Winter mix risk

Jan - Dec

Even light snow or freezing precipitation can matter more than usual when this route turns into a same-day commitment.

Best Departure Time by Season

Spring

9 AM to 12 PM

Waiting for a little daylight and warmer pavement usually makes the drive easier.

Summer

7 AM to 10 AM

This is short enough that a mid-morning departure still keeps the whole drive comfortable.

Fall

9 AM to 12 PM

Waiting for a little daylight and warmer pavement usually makes the drive easier.

Winter

7 AM to 10 AM

A morning departure gives you more room to adjust if rain slows the drive down.

How This Score Was Built

Source

Route-sampled NOAA climate normals

High confidence. Built from 3 NOAA-backed route checkpoints rather than a single statewide estimate.

Origin zone

Pacific Coast

Destination zone

Pacific Coast

Route sample points

Late route

Late route checkpoint

OR statewide fallback (0 mi away)

Late route

Late route checkpoint

OR BONNEVILLE DAM (3.4 mi away)

Destination

Keizer, OR

OR KEIZER 1.4 SSW (0.4 mi away)

Ready to plan? See the full trip plan from Hermiston, OR to Keizer, OR with stops, fuel costs, and directions.