Clothing:
* Warm, waterproof jacket or raincoat (Seattle gets a lot of rain)
* Layering clothes (the weather can be unpredictable)
* Comfortable shoes for walking
* Hat and gloves for cooler weather
* Swimsuit and beach towel (if you're visiting in the summer)
Toiletries:
* Toothbrush, toothpaste, and other personal care items
* Makeup (if you wear it)
* Hairbrush and hair styling products
* Sunscreen and insect repellent
* Any prescription medications you take
Electronics:
* Phone and charger
* Camera and charger
* Laptop or tablet (if desired)
* Headphones
Documents:
* ID (driver's license or passport)
* Travel insurance (if applicable)
* Hotel reservation confirmation
* Flight itinerary
Other essentials:
* Water bottle
* Snacks
* Small amount of cash (for tips, etc.)
* Travel guide or map of Seattle
* Umbrella
* Reusable shopping bag
Optional items:
* Book to read
* Travel pillow and blanket (for long flights or train rides)
* Small flashlight
* First-aid kit
* Travel adapter (if you're coming from a country with a different electrical outlet type)