30YearWeather
Seattle in December
Seattle weather in December - United States
🌧️Wet Season

Seattle Weather in December

Plan your December trip to Seattle, United States. Based on 30 years of NASA data, expect temperatures of 7°C (high) to 2°C (low), with 50% rain probability and 8 hours of daily sunshine. Pack rain gear for around 31 rainy days.

Avg High
7°C

Hottest around day 10

Avg Low
2°C

Coolest around day 24

Rainy Days
31days

50% avg rain chance

Sunshine
8hrs/day

Winter season

Seattle December Weather Calendar

Click any day to see detailed weather information

Currency

USD

$ United States dollar

Language

English

Driving

Right side

Connect

The area code for the City of Seattle is...

Safety

Moderate Safety

GPI: 2.44

Travel Intelligence

Exclusive flight analytics & health data for Seattle

Smart Flight Estimator

Airport-to-Airport Logistics

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Add your home location in settings to see airport details.

Flight Connectivity Analysis

Airport traffic data & seasonal patterns

Major Hub
87/ 100
Traffic Index

Extremely busy airport

Peak Daily Arrivals

0

slots per day

Peak

May

Low

Nov

Monthly Traffic Distribution

508
Jan
533
Feb
558
Mar
595
Apr
740
May
696
Jun
707
Jul
713
Aug
675
Sep
584
Oct
498
Nov
575
Dec
Traffic Level
Low Season

Key Connections

Phoenix Sky Harbor (PHX)
Los Angeles (LAX)
San Francisco (SFO)
Anchorage Ted Stevens (ANC)
Denver (DEN)

Health & Safety Advisory

CDC travel health recommendations

No Requirements

No Special Vaccinations Required

Standard travel precautions apply

Source: CDC Travelers' Health

View Complete Health Guide

Is December a Good Time to Visit Seattle?

👌A reasonable choice for your trip
Short Answer

Monsoon conditions shape Seattle's December: expect 50% daily rain chance. Mornings often clear before afternoon showers - early starts recommended.

Decision Factors

Very high humidity

84% average humidity

Frequent rainfall expected

50% chance of rain - pack waterproofs

Near active volcano: Mount Rainier

Medium volcanic risk

Shoulder season - balanced conditions

78% of peak - good value with moderate crowds

Good For

  • 🏛️
    Cultural tourists

    Comfortable conditions for exploring museums and sites

  • 💼
    Business travelers

    Climate-controlled meetings unaffected by weather

Who Should Avoid

  • 🏖️
    Beach lovers

    Sea temperature only undefined°C - too cold for comfortable swimming

  • 👴
    Elderly travelers

    84% humidity creates difficult conditions

  • 📸
    Photographers

    79% cloud cover limits natural light opportunities

  • 💑
    Honeymoon couples

    Wedding score only 38/100 - better months available

930 observations30-year historical data
Confidence: 95%

"According to 30YearWeather's analysis of 30 years of NASA POWER satellite data,Seattle in December averages 7°C with 50% precipitation probability."

📊 Source: 30YearWeather.com🛰️ Data: NASA POWER (1991-2021)View Methodology →

Frequently Asked Questions: Seattle in December

What are the temperatures in Seattle in December?

Daytime highs average 7°C, nights drop to 2°C. Temperatures remain fairly consistent.

How many rainy days in Seattle in December?

Expect around 31 days with measurable rainfall. An umbrella is advisable.

What to wear in Seattle in December?

Warm winter clothing: insulated jacket, boots, gloves.

Is December peak season in Seattle?

This is off-peak season. Expect lower prices and fewer crowds.