Olympic National Park stands out as one of the most climatically diverse places in the U.S. You can experience everything from temperate rainforests to snowy alpine ridges, sometimes in a single day.
The park’s spot on Washington’s Olympic Peninsula creates a tangled web of weather that shifts fast across elevations and regions. Weather in Olympic National Park is highly variable and unpredictable throughout the year. Temperatures can swing by 10 to 20 degrees between the coast and higher elevations, even in summer.
This wild diversity comes from the park’s geography—coastal stretches, thick forests, and mountain peaks all packed close together. Each creates its own little climate bubble.
If you’re planning to explore the park’s different ecosystems, you’ll want to get familiar with these weather patterns. Rain shadow effects, sudden seasonal shifts, and microclimates can turn sunny trails into snowfields. The park’s conditions shape everything from wildlife behavior to how safe your hike will be. Honestly, knowing the weather might be the most important thing you can do before heading out.
Overview of Weather Patterns in Olympic National Park
Olympic National Park gets some of the most diverse weather patterns in Washington. The park’s position between the Pacific Ocean and the mountains sets up major climate zones, each with its own rainfall and temperature quirks.
Geographical Influences on Weather
The Olympic Mountains block Pacific storm systems. This sets up a rain shadow effect that feels almost unfair.
Western Slopes: Storms from the ocean drop tons of moisture as they climb the mountains. The west side can see 100-170 inches of rain every year.
Eastern Slopes: By the time storms cross over, most of the moisture is gone. Port Angeles gets just 25-30 inches annually.
That’s a huge difference for such a short distance. The park headquarters gets about six times less rain than coastal areas just a few miles away.
Hurricane Ridge is a great example of how elevation changes things. Up here, you might see 30-35 feet of snow each year, while lower spots stay snow-free.
Temperatures can swing 10-20 degrees between locations on the same day. The coast stays pretty mild, but the peaks can be icy cold.
Key Weather Phenomena
Weather here stays unpredictable all year. Sometimes you’ll find totally different conditions just a few miles apart.
Summer is usually the most stable time, from July through August. Temps hit 65-75°F in most spots. But coastal fog can hang around and make beaches hard to see.
Winter storms dump the most rain between November and April. Rain forests soak up most of their annual 140 inches during these months.
Spring is a mixed bag well into June. Higher elevations can still get snow or heavy rain late in the season. Many mountain trails stay buried under snow.
Fall brings cooler temps and more rain by late September. Snow starts showing up in the high country, and wind and rain sweep into the lower areas by October.
Impact on Ecosystems
The Olympic Mountains’ rainfall extremes support three different ecosystems.
Temperate Rain Forests thrive in the damp western valleys. The Hoh and Quinault rain forests count on all that rain to stay lush. These old forests need steady moisture all year.
Dry Lowland Forests take over on the east side, where rain drops off. These forests have learned to make do with much less water.
Alpine Environments sit above the tree line. Heavy snow and short growing seasons keep plant life sparse. These are the park’s wildest weather zones.
Wildlife in the park adapts to these climate zones. You’ll notice that animal populations often follow the patterns of rainfall across the peninsula.
Seasonal Weather Trends
Olympic National Park goes through big seasonal shifts every year. Winter brings heavy rain and snow, while summer is warmer and much drier.
Winter Conditions
Winter turns Olympic National Park into a place of wild contrasts. The west side gets 100-170 inches of rain each year, most of it falling between November and April.
Up in the mountains, snow piles up. Hurricane Ridge usually sees 30-35 feet of snow a year, which is perfect for winter sports if the weather lets you get there.
Lower elevations stay pretty mild, even with all that rain. Coastal and rainforest valleys don’t freeze often, though nights can dip below 32°F.
The rain shadow really shows up in winter. Western slopes get hammered with rain, but places like Port Angeles see just 25-30 inches a year.
Winter storms can shut down roads and limit access. Flooding and severe weather often close parts of the park, so you’ll want to check conditions before heading out.
Spring Changes
Spring weather keeps you guessing, even as things warm up. Snow and heavy rain can stick around through June at higher elevations, making many mountain trails a no-go.
Temperatures bounce from cool to mild. You might see 10-20 degree differences between the coast and the mountains on the same day.
Rain starts to taper off, but it’s still pretty common. Melting snow feeds rivers and waterfalls, helping the park’s ecosystems gear up for summer.
Spring is a popular time to visit. Campgrounds start reopening, but dates depend on how much snow is left and whether the trails are clear.
Trail conditions change fast in spring. High-elevation routes can stay snowed in until late in the season, so hiking options may be limited up high.
Summer Characteristics
Summer is the sweet spot for weather in Olympic National Park. July and August bring the warmest temps and the least rain, with up to 9 hours of sunshine a day.
Most areas see 65-75°F during the day, but elevation and location can still make a big difference.
Even with mostly sunny skies, weather can flip. Rain is always possible, and thunderstorms can pop up fast in the mountains, so don’t leave your rain gear at home.
The coast has its own thing going on. Fog often lingers along the beaches, making it cooler and harder to see than inland.
Summer draws the biggest crowds. Most trails open up, and campgrounds usually fill up during peak months.
Autumn Transitions
Autumn cools things down and brings more rain. Snow can show up in the mountains as early as late September—winter’s not far off.
Lower elevations get more rain and wind by late October. The rainforests and beaches slip back into their wet-season routines after summer dries out.
Temps start to split by elevation. The mountains freeze regularly, while the lowlands usually stay above freezing except at night.
Fall weather can shut down parts of the park. Some campgrounds and roads close for maintenance, and early snow can make trails tricky.
If you visit in autumn, you’ll want to be ready for anything. Weather can swing from pleasant to nasty in just a few hours, especially up high.
Temperature Variations Throughout the Year
Olympic National Park sees big temperature swings from winter to summer. Coastal areas and mountain peaks can feel like totally different worlds on the same day.
The peninsula’s unique location sets up zones where temps change a lot with elevation and season.
Monthly Temperature Averages
Winter temps stay pretty mild for a mountain park. January and December average highs around 44°F, with lows near 34°F.
Spring warms things up slowly. March days hit 52°F, nights stay cool at 35°F. By May, you might see 62°F during the day and 43°F at night.
Summer is the warmest. July and August peak at 70-72°F, with nights around 50°F. These months usually give you the best shot at good weather.
Fall cools off steadily. September holds onto 69°F highs, but by October it’s down to 59°F. November feels like winter again, with 49°F days.
| Month | High Temperature | Low Temperature |
|---|---|---|
| January | 44°F | 34°F |
| April | 57°F | 38°F |
| July | 70°F | 50°F |
| October | 59°F | 42°F |
Temperature Extremes by Region
The coast keeps temperatures pretty moderate all year. Ocean air stops winter lows from dropping much below freezing, and summer highs rarely go over 75°F.
The Hoh Rain Forest and other west-side valleys get mild conditions too. Maritime air smooths out the extremes in both summer and winter.
Interior valleys swing more wildly. Without the ocean’s influence, summer days can reach 80°F, and winter nights get colder than the coast.
Eastern parts of the park see the biggest range. You’ll find the hottest summer days and the coldest winter nights here.
Elevation Effects on Temperatures
Hurricane Ridge and other high spots feel totally different from the lowlands. For every 1,000 feet you climb, temps drop about 3-5°F.
Winter at 5,000+ feet means heavy snow and long stretches below freezing. Hurricane Ridge can stay under 32°F for weeks, even while the coast stays above 40°F.
Summer in the mountains stays cool, even during heat waves. High elevations rarely top 65°F, even when it’s hot down below.
Mount Olympus and the highest peaks are cold nearly all year. Glaciers stick around up here, even as lower elevations warm up.
Snow melts from the bottom up. Coastal trails open in March, but high-country routes might not clear until July.
Precipitation and Rainfall Patterns
Olympic National Park gets wild swings in rainfall. Western areas soak up as much as 170 inches a year, while the east side can get just 25. The Olympic Mountains set up this dramatic difference by steering Pacific storms.
Rainfall by Season
Winter is the wettest time. Rainforests and coastal areas pull in 100-140 inches between November and April.
During these months, Pacific storms bring steady moisture to the park’s west side. Temps stay mild in the lowlands, but can dip below freezing now and then.
Spring keeps things unpredictable. Rain and even snow can last through June up high. The park gets a lot of visitors during this season.
Summer dries out. July and August are the least rainy months, but you’re never totally safe from a shower. The coast might still get foggy, even when it’s sunny inland.
Fall brings rain back. By late October, wind and wet weather hit the lower areas. Storm patterns start to shift again.
Rain Shadow Effect
The Olympic Mountains set up a big rain shadow effect that shapes how much rain each area gets. Pacific storms hit the peaks and drop most of their moisture there.
Western valleys and the coast get 100-170 inches of rain a year. That’s why the Hoh and Quinault rainforests are so lush.
On the east side, it’s a different story. Port Angeles averages only 25-30 inches of rain because the storms already spent themselves on the west side.
This rain shadow sets up totally different ecosystems. Lush rainforests grow on the west, while drier forests take over on the east—sometimes just a few miles apart.
Snowfall and Its Distribution
Snow piles up very differently depending on where you are. Hurricane Ridge usually gets 30-35 feet of snow each winter.
The Olympic Mountains collect huge snow totals in winter. This snowpack is key for the region’s rivers and ecosystems.
Lower elevations don’t see much snow. Coastal and rainforest areas get most of their winter precipitation as rain, thanks to milder temps.
High-elevation spots can get snow as early as late September. The mountains start freezing in fall, while the lowlands rarely freeze except overnight.
Sunshine and Cloud Cover
Olympic National Park swings between long, sunny summer days and short, cloudy winter ones. In summer, you might get up to 16 hours of daylight, but winter drops to just 8.5. The park’s location sets up patterns of clear and cloudy skies that can totally change your visit.
Monthly Sunshine Hours
Daylight hours in Olympic National Park shift a lot as the seasons change. June brings the longest days with up to 16 hours of daylight.
This peak slowly drops through summer and into fall. It’s a noticeable change if you’re out there.
Summer months really give you the most sunshine:
- June: 16 hours of daylight
- July: 15.7 hours of daylight
- August: 14.2 hours of daylight
Winter brings the shortest days. December barely scrapes by with 8.5 hours, making it the darkest stretch of the year.
January and February hang around 9 hours each. Not much time for wandering outdoors.
Spring ramps things up again. March starts with 11.9 hours and by May, you get 15.2 hours. Longer days mean more room for adventure.
The park’s northern latitude really drives these swings in daylight. If you’re visiting in winter, you’ll need to plan carefully since daylight disappears fast.
Typical Cloudy and Clear Days
Cloud cover in the park pretty much follows the rainfall patterns. Summer months from June through September usually bring the clearest skies.
These months also tend to be the driest, so you get a double bonus. Not a bad time to visit if you like sunshine.
Winter and early spring? Get ready for heavy cloud cover. December and January seem to get hit hardest, thanks to frequent Pacific storms.
Rain systems roll in and keep things cloudy for days. That’s just how it goes out here.
The coastal areas deal with more clouds than inland spots. Marine layers and fog often make the coastline feel mysterious, sometimes even a bit gloomy.
Hurricane Ridge and higher elevations can actually see clearer skies when the lowlands are socked in. It’s a weird, cool contrast.
Autumn brings more clouds as storms return. September can start off clear, but by November, it’s often just gray.
Best Times for Sunlight
July stands out as the clearest month. Rainfall drops to just 0.8 inches and you get the longest days. Photographers and hikers usually love this window.
Late spring through early fall? That’s your best bet for reliable sunshine. May through September gives you a great mix of long days and clear skies.
August keeps the streak going with 14.2 daylight hours and not much rain. Hard to complain.
Morning hours usually offer the clearest conditions. Clouds often build up in the afternoon, especially during those in-between seasons.
If you get up early, you’ll probably catch the best light and views. That’s true almost any time of year.
Winter visitors should aim for midday to maximize light. With only 8.5 to 9.3 hours of daylight, timing gets a little tricky.
Regional Climate Differences Within the Park
Olympic National Park stretches across nearly a million acres on the Olympic Peninsula. That means the climate can change a lot depending on where you are.
The coast gets steady temperatures and lots of rain. Inland rainforests soak up over 140 inches of precipitation each year, while the mountains deal with serious snowfall and colder, alpine weather.
Coastal vs. Inland Weather
The coastal parts of Olympic National Park keep temperatures pretty steady all year. Summer highs rarely top 70°F, and winter lows usually stay above 35°F.
Ocean breezes help smooth out temperature swings along the coast. These areas also see plenty of clouds and light rain, sometimes for weeks at a time.
Inland, the story changes. Summer temps can climb to 80°F or more in valleys and forests. Winters get colder, especially up high, with temps often dipping into the 20s.
Precipitation patterns really set these zones apart. Coastal areas get 25-35 inches a year, while some valleys farther in rack up over 100 inches.
There’s even a rain shadow on the park’s northeast side, where a few spots get less than 20 inches annually. It’s a surprising dry patch.
Wind can be fierce along the coast, especially when winter storms hit. Inland areas stay calmer, but mountain passes sometimes funnel strong winds through.
Rainforest Microclimates
The Hoh and Quinault rainforests create unique microclimates inside the park. These spots collect 120-140 inches of rain each year, which keeps the temperate rainforest thriving.
Humidity levels stay high all the time. The forest canopy traps moisture, leading to foggy mornings even when it hasn’t rained.
Temperatures barely budge because of all that moisture. You won’t see much wild fluctuation.
These rainforests see:
- Year-round green conditions—hardly any seasonal dormancy
- Consistent temperatures between 40-65°F, no matter the month
- Heavy rainfall from October through April
- Frequent fog in summer, which can feel oddly cozy
The dense canopy keeps the ground cooler than open spots nearby. Under the trees, it’s usually 5-10 degrees cooler.
Stream valleys in the rainforest stay even more stable. They rarely freeze and support plants you just won’t find anywhere else in the region.
Mountainous Zones
Olympic National Park’s mountain regions sit above 4,000 feet. Up here, you get true alpine conditions.
Heavy snowfall hits these areas from November through April. In some high mountain basins, snow piles up over 20 feet deep.
A few spots keep their snow cover all year. That lingering snow feeds the park’s glaciers.
Temperatures swing wildly between day and night at elevation. You might see 70°F in the afternoon, but then it drops close to freezing, even in July or August.
Weather in the mountains changes fast. Clear mornings sometimes turn into afternoon thunderstorms or surprise snow squalls, even in the heart of summer.
Elevation zones shape the climate pretty dramatically:
- 3,000-5,000 feet: You’ll get a mix of snow and rain, and winter stretches on.
- 5,000-7,000 feet: Expect heavy snow and a short growing season.
- Above 7,000 feet: It’s all alpine—permanent snowfields, not much else.
Winds pick up as you climb higher. Exposed ridges and peaks get battered by constant gusts, making life tough for most plants except those hardy alpine specialists.