Halloween in Washington usually brings cool air, early sunsets, and a decent chance of light rain. You’ll typically see temperatures in the low to mid-50s during the day, and evenings often slip into the 40s.
It doesn’t always feel freezing, but dampness can make it seem colder after dark.
The state’s varied landscape means your Halloween can feel totally different depending on where you spend it. West of the Cascades, you’re more likely to get drizzle and clouds, while east of the mountains, things trend drier but colder.
This makes planning costumes and activities a bit of a guessing game if you don’t know what’s normal.
Knowing the patterns helps you get ready for both comfort and fun. Whether you’re wandering Seattle neighborhoods, checking out a small-town festival, or braving Spokane’s crisp autumn air, knowing what to expect weather-wise makes Halloween run smoother.
Typical Halloween Weather in Washington
When you’re planning for Halloween in Washington, expect cool temps, a chance of rain, and an early sunset. The climate shifts between the west and east sides, but you’ll almost always get crisp evenings and some dampness that shapes your outdoor plans.
Average Temperatures on October 31
On Halloween, temperatures across Washington usually land in the 40s to 50s°F. In western cities like Seattle, afternoon highs often hit the mid-50s, and lows drop into the low 40s by night.
Eastern Washington, places like Spokane, runs cooler. Highs hover around 50°F, and nighttime lows can fall to the mid-30s. The Cascade Mountains block marine air from reaching the east, causing this difference.
You’ll notice a chill after sunset, especially if you’re out trick-or-treating. Light jackets or layered costumes really help, especially where temps drop fast after dark.
Rainfall and Precipitation Patterns
Rain shows up often on Halloween in western Washington. Seattle, for instance, averages about 0.3 to 0.4 inches of rain on October 31. Most years bring at least a bit of precipitation, though the totals can swing a lot.
Some years, you’ll just get a trace of drizzle, but others have brought over an inch in a single day. Because it’s so unpredictable, you should always prep for damp weather if you’re celebrating outdoors west of the Cascades.
Eastern Washington stays drier. Spokane and nearby areas usually get clearer skies, but light showers can still pop up. This east-west split makes planning important if you’re traveling across the state.
Daylight Hours and Sunset Timing
By late October, daylight in Washington gets pretty limited. On Halloween, the sun sets between 5:45 and 6:00 p.m. in western cities like Seattle, with Spokane seeing sunset about 10 minutes earlier.
That early darkness means most trick-or-treating starts after sunset. Temperatures drop quickly once the sun’s gone, so evenings feel colder than the daytime highs suggest.
Daylight lasts about 10 hours on October 31, way less than the nearly 16 hours you get midsummer. Keep that shorter window in mind if you’re traveling or trying to squeeze in events before nightfall.
Regional Differences in Halloween Weather
Halloween weather in Washington really depends on your location. Coastal areas and the Puget Sound usually get damp, mild conditions, while inland regions like eastern Washington cool down faster and stay drier. Seattle’s climate sits somewhere in the middle, shaped by marine influence and local quirks.
Western Washington and Puget Sound
If you’re spending Halloween in western Washington, expect a mix of rain and cool air. The marine climate keeps things moderate, but frequent showers are just part of the deal. Highs often settle in the mid-50s, and lows fall into the 40s.
The Puget Sound region gets famous for cloudy skies and light drizzle this time of year. Storms can roll in fast, bringing gusty winds that make trick-or-treating feel colder than it looks on paper.
You won’t get rain every single year, but it’s a lot more likely here than anywhere else in the state. A light rain jacket or umbrella is a smart move if you’ll be outdoors.
Eastern Washington Climate Variations
Halloween in eastern Washington feels different thanks to its inland spot and drier air. Nights cool down fast, and temperatures often drop into the 30s. Daytime highs usually stick to the upper 40s or low 50s, which is definitely chillier than the west side.
Rain is less likely here. Skies are often clearer, but that also means colder evenings. Frost happens, and sometimes you’ll even see a little snow in higher spots.
If you’re planning outdoor activities, get ready for bigger temperature swings. A warm afternoon can quickly turn into a chilly evening, so layering is your friend.
Seattle Halloween Weather Overview
Seattle’s Halloween weather really shows off its coastal vibe. Average highs hang around the low to mid-50s, and lows usually land in the 40s. Rain is common, but some years, dry and calm evenings show up when high pressure blocks storms.
Seattle sits between the Cascades and Puget Sound, so conditions can flip fast. One neighborhood might get steady drizzle while another stays dry. Wind off the water can make it feel colder than inland suburbs.
If you’re planning to walk the city on Halloween night, expect damp pavement and cool air. Usually, waterproof shoes and a light jacket are enough to keep you comfortable.
Notable Weather Events and Trends
Halloween weather in Washington has ranged from heavy rain to freezing nights and even record warmth. You’ll see a lot of variety, with some years bringing steady showers while others stay cool and dry.
Historical Extremes and Records
Weather records show Halloween in Washington has brought both the wettest and coldest days of the season. At Sea-Tac Airport, the wettest Halloween happened in 1994 with 1.04 inches of rain in one day. Olympia saw almost 3 inches that year, and Hoquiam got over 2 inches.
Cold snaps have made some Halloweens stand out. Olympia hit a low of 14°F in 2002, and Bellingham dropped to 20°F in 1984. Sea-Tac reached a record low of 30°F in 2006.
Warm years pop up too. In 1949, Olympia reached 74°F, and Sea-Tac got to 71°F. These swings really show how unpredictable late October can get in western Washington.
If you’re trick-or-treating or running outdoor events, be ready for soaking rain or frosty nights depending on the year.
Recent Halloween Weather Trends
In Seattle, historical data shows measurable rain on Halloween about 57% of the time. So, odds are just a bit better than even that you’ll need a raincoat. Most years, rainfall totals are light, with a lot of years bringing just a quick shower.
Recent decades show a warming trend. Cooler nights still happen, but average high temperatures now lean toward the mid-50s instead of the lower 50s of the past. Evenings aren’t as harsh, but rain still shows up regularly.
Since the early 2000s, about half the Halloweens in western Washington have been rainy. Dry evenings aren’t rare, though, and when they happen, you usually get cooler, clearer skies.
For planning, expect mild but damp conditions, with the occasional year bringing either record rain or crisp, dry air.
Weather in Iconic Washington Locations
At higher elevations in Washington, late October weather can flip in a hurry. You’ll often see cold nights, daytime highs near or below freezing, and a mix of rain and early snow depending on altitude. Visibility, road access, and trail safety can change fast.
Mount Rainier and Surrounding Areas
Mount Rainier’s weather in late October is cold and unsettled. Around the park entrances, daytime highs usually stay in the 40s °F, and nights dip into the 30s °F. Rain is common, and the higher slopes often get the first real snow of the season.
Above 5,000 feet, snowpack starts to build. Paradise, at 5,400 feet, often sees several inches of snow by Halloween. Trails get icy, and clouds can limit visibility a lot.
You’ll also notice shorter daylight hours. Sunset happens before 6 p.m., making hikes harder to plan. If you’re heading past the visitor centers, bring layers, waterproof gear, and traction devices.
Mount Baker and Northern Cascades
Mount Baker and the northern Cascades get similar late October patterns, but it’s often wetter because of the Pacific moisture flow. Lower valleys might see highs in the mid-40s °F, while upper slopes stay below freezing.
Rain dominates at lower elevations, but snow is common above 4,000 to 5,000 feet. Mount Baker Ski Area, at about 4,200 feet, can get its first measurable snowfalls by Halloween. Travel on mountain roads can slow down with slush or early ice.
Clouds show up a lot, with clearer breaks more likely in the morning. Strong winds hit the ridges and passes. If you’re planning a visit, get ready for fast-changing mountain weather and limited services once you leave towns like Glacier.
Weather Impacts on Halloween Activities
Rain, chilly evenings, and early sunsets all shape how you plan for Halloween night in Washington. Conditions can change a lot, so knowing what’s typical helps you stay comfortable and safe while having fun.
Trick-or-Treating Considerations
Rain on Halloween is pretty common in western Washington, but it’s not a sure thing. Seattle’s seen both wet and dry nights, and temperatures can swing from the low 30s to the upper 50s. Plan for cool, damp weather even if the day starts out dry.
Clothing choices matter. Layer costumes over warm clothes, and think about waterproof jackets or ponchos. Umbrellas are tough for kids to handle, so hoods and hats are usually better. Reflective tape or glow sticks help costumes stand out after dark, especially on rainy nights with low visibility.
Watch out for sidewalk conditions. Wet leaves get slippery, and puddles form near curbs. Sturdy shoes with good grip help prevent falls. In eastern Washington, where it cools off faster, gloves and hats might matter more than rain gear.
If you’re heading out in Spokane or Pullman, expect colder air and a higher chance of steady rain compared to Seattle. Always check the local forecast before you leave so you know if you’ll get showers, drizzle, or a rare dry night.
Outdoor Events and Safety Tips
Lots of communities run outdoor gatherings like pumpkin walks, haunted trails, or block parties. These events usually go on rain or shine, so being prepared keeps things fun.
Pack a small bag with essentials:
- Extra layers for warmth
- Light rain gear
- Flashlights or headlamps for dark paths
- Dry socks if puddles are in play
Pacific storms sometimes bring wind in western Washington. Outdoor decorations or tents at events can blow around, so be careful near temporary setups. In the east, the bigger issue is the cold, which can make standing outside rough without enough layers.
Parking and travel get trickier with bad weather. Wet roads in Seattle slow traffic, and fog in rural valleys can cut visibility. Give yourself extra time to get there safely.
If you’ll be outdoors for a while, pick spots with covered areas or indoor options nearby. That way, you can warm up or dry off if the weather turns ugly.
Preparing for Halloween Weather in Washington
Weather in Washington around Halloween changes fast, with cool evenings, damp conditions, and the occasional rain shower. You’ll want to plan for comfort and safety, especially if you’re heading out for trick-or-treating, community events, or traveling between neighborhoods.
Clothing and Costume Recommendations
Late October evenings usually dip into the 40s or 50s. In western Washington, rain pops up pretty often, while eastern spots might get colder, sometimes with fog or even a bit of light snow.
It’s smart to pick costumes that let you layer up or down, depending on the weather. If you’re planning to be outside for a while, grab some water-resistant outerwear.
A thin rain jacket or poncho over your costume really does the trick. For kids, I’d go with bright or reflective stuff—it just makes them easier to spot in the dark.
Footwear matters more than you’d think. Wet leaves and sidewalks get slick fast, so sturdy shoes or boots with decent grip beat flimsy costume shoes every time.
Gloves and hats can make a huge difference if things get chillier than you expected. When you’re making or picking out a costume, look for fabrics that dry fast and don’t soak up water.
Try to skip long hems that drag on the ground, especially if it’s wet. They just make tripping way more likely.
Travel and Event Planning Tips
You’ll probably notice traffic picking up on Halloween evening, with families heading out to neighborhoods and events. If it’s raining or foggy, you might need to leave earlier—visibility drops fast around here.
Over in western Washington, you can almost count on light showers. Eastern towns, though, tend to get colder, so you’ll want to drive with extra care.
Try planning your route ahead of time. I’d stick to well-lit streets and skip those muddy or uneven shortcuts.
Hosting an event? Set up some tents or covered spots so people can actually stay dry.
Public transportation usually keeps its regular schedule, but buses slow down when it’s wet. If you take transit, it’s worth checking for delays before you head out.
Parking near popular trick-or-treat spots fills up quickly. Show up early, or maybe carpool to avoid the headache.
Honestly, tossing a couple of umbrellas and jackets in your car isn’t a bad idea. The weather can turn on you pretty fast.