Mercer Island, Washington, United States of America: What to pack, what to wear, and when to go [2022]
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Traveling to Mercer Island, Washington, United States of America? If you're planning to go to Mercer Island, here is some important information about when to go, what to wear, and what to pack.
Contents
- When to go to Mercer Island
- Important essentials for Mercer Island
- Activities for Mercer Island
- Mercer Island in January: weather and what to pack
- Mercer Island in February: weather and what to pack
- Mercer Island in March: weather and what to pack
- Mercer Island in April: weather and what to pack
- Mercer Island in May: weather and what to pack
- Mercer Island in June: weather and what to pack
- Mercer Island in July: weather and what to pack
- Mercer Island in August: weather and what to pack
- Mercer Island in September: weather and what to pack
- Mercer Island in October: weather and what to pack
- Mercer Island in November: weather and what to pack
- Mercer Island in December: weather and what to pack

About your travel guide
Hi! I'm Dev. I've traveled all over the world and in my travels, I have made many packing lists. In this series, my team and I have compiled the most useful information, as well as things we couldn't live without, to help you plan your trip.
When to go to Mercer Island, Washington, United States of America
Based on the climate and weather in Mercer Island, the best time to go is July. See below for details.
Important essentials for Mercer Island, Washington, United States of America
Here are some general tips on what to wear in Mercer Island, as well as several items to remember to pack when traveling there.
COVID-19 ESSENTIALS FOR 2022
-
Kids' KN95 masks
N95 masks aren't sold for kids. These are a good alternative (and can also be used by adults if N95 masks are not available).
-
A vaccine card protector
Vaccine cards frequently get worn. An unreadable vaccination card can cause severe consequences. This vaccine card protector helps stop that.
-
Hand sanitizer
This hand sanitizer is a good TSA-friendly option.
-
N95 masks to use in crowded airports
These N95 masks provide the best level of COVID protection possible.
Travel insurance
If you or a companion get COVID-19, your amazing trip can be ruined. Good travel insurance can help. See plans
-
Travel disinfecting wipes
Use these to sanitize plane and hotel surfaces.
General health necessities
Don't forget these
-
Power bank for devices
A portable power bank, like this one
-
Money/passport pouch
A money pouch is vital for protecting your passport and credit cards.
-
Airplane or car necessities
-
For families with young children
-
Voice and data SIM card
A SIM card that works in Mercer Island. A good global SIM card works in most countries, but check the country list before buying.
-
Plug adapter
A plug adapter that supports outlet types A and B. This one should work in most areas, but you should check with your hotel.
What to wear/what to pack for Mercer Island, Washington, United States of America by month
Already know when you're traveling?
January
January in Mercer Island can be very chilly and very rainy. The rain can amount to several inches/centimeters. During this time, temperatures average in the high 40s F (single digits C), although night temperatures can dip into the low 30s F (single digits C).
What to wear/what to pack:
-
Fleece
-
Light gloves or mittens
-
Jacket or coat
-
Lip balm
In our opinion, the best pick: this one
-
Extra socks
-
Warm pants or jeans
-
Standard footwear
-
A rain coat to layer with a coat
-
100% waterproof footwear
We recommend rain boots:
-
Rain pants
These can be vital in a rainstorm.
-
Waterproof phone bag
-
Umbrella
This one is a perfect one to buy.
-
Waterproof bag/luggage cover
So your belongings remain dry. We suggest:
February
February in Mercer Island can be very chilly and somewhat rainy. The rain can amount to several inches/centimeters. During this time, temperatures average in the low 40s F (single digits C) to low 40s F (single digits C), although night temperatures can dip into the low 30s F (single digits C).
What to wear/what to pack:
-
Light gloves or mittens
-
Jacket or coat
-
Extra socks
-
Fleece
-
Warm pants or jeans
-
Lip balm
In our opinion, the best is: this
-
Standard footwear
-
A rain jacket to layer with another jacket
-
100% waterproof footwear
We use rain boots:
-
Rain pants
These pants will be essential in heavy rain.
-
Waterproof phone bag
-
Wind resistant umbrella
This one is a great choice.
-
Waterproof bag/luggage cover
So your belongings remain dry. We suggest:
March
March in Mercer Island is pretty cool and very rainy. The rain can amount to several inches/centimeters. During this time, temperatures average in the high 40s F (single digits C) to 50s F (low 10s C), although night temperatures can dip into the low 30s F (single digits C).
What to wear/what to pack:
-
Light gloves or mittens
-
Jacket or coat
-
Warm pants or jeans
-
Lip balm
In our opinion, the best choice: this
-
Fleece
-
Extra socks
-
Standard footwear
-
A rain jacket to layer with a jacket
-
100% waterproof footwear
We use these rain boots:
-
Rain pants
Rain pants are a lifesaver in a rainstorm.
-
Waterproof phone bag
-
Umbrella
This one is a perfect one to buy.
-
Waterproof bag/luggage cover
So your suitcases don't get wet. We recommend:
April
April in Mercer Island can be chilly and somewhat rainy. The average overnight temperatures in the area are in the low 40s F (single digits C). It tends to rain about half of the time.
What to wear/what to pack:
-
Extra socks
-
Pants or jeans
-
Dresses
-
Standard footwear
-
Light and heavy skirts
-
Long sleeve shirts or blouses
-
Light jacket or fleece
-
A rain coat to layer with a jacket
-
100% waterproof footwear
We use these rain boots:
-
Rain pants
These are a lifesaver in a storm.
-
Waterproof phone bag
-
Umbrella
This one is an excellent choice.
-
Waterproof bag/luggage cover
So your things don't get wet. We recommend:
May
May in Mercer Island is cool and somewhat rainy. The rain can amount to several inches/centimeters. During this time, temperatures average in the 60s F (high 10s C), although night temperatures can dip into the 40s F (single digits C).
What to wear/what to pack:
-
Light jacket or fleece
-
Standard footwear
-
Dresses
-
Light and heavy skirts
-
Pants or jeans
-
Extra socks
-
Long sleeve shirts or blouses
-
A rain coat to layer with a coat
-
100% waterproof footwear
We use rain boots:
-
Rain pants
These are a lifesaver in a storm.
-
Waterproof phone bag
-
Wind resistant umbrella
This one is an excellent choice.
-
Waterproof bag/luggage cover
So your suitcases stay dry. We like:
June
If you visit Mercer Island during June, you might see that it is mild. Temperatures tend to hover around the low 60s F (low 20s C) during the day, while at night they can dip into the low 50s F (low 10s C). In terms of precipitation, you can expect it to rain a bit less than half of the time.
What to wear/what to pack:
-
Standard footwear
-
Long sleeve shirts or blouses
-
Extra socks
-
Light and heavy skirts
-
Pants or jeans
-
Dresses
-
Light jacket or fleece
-
A rain jacket to layer with a jacket
-
100% waterproof footwear
We suggest rain boots:
-
Rain pants
Rain pants are essential in heavy rain.
-
Waterproof phone bag
-
Wind resistant umbrella
This one is a perfect choice.
-
Waterproof bag/luggage cover
So your things stay dry. We recommend:
July
July for Mercer Island is a perfect temperature. Temperatures average in the 70s F (mid 20s C) during the day. It rains occasionally.
What to wear/what to pack:
-
Long and short sleeve shirts
-
Sandals
-
Sunscreen lotion
-
Extra socks
-
Light skirts
-
Bug repellent
-
Breathable footwear or sandals
-
Short pants or heavy shorts
-
Light dresses
You can find some great options here
-
Beach necessities
If you're going to the beach:
-
A rain coat to layer with a coat
-
100% waterproof footwear
We recommend rain boots:
-
Rain pants
These will be a lifesaver in heavy rain.
-
Waterproof phone bag
-
Windproof umbrella
This one is a great choice.
-
Waterproof bag/luggage cover
So your things remain dry. We recommend:
August
If you visit Mercer Island during August, you may notice that it is warm. Temperatures tend to hover around the 70s F (mid 20s C) during the day, while at night they can dip into the 50s F (low 10s C). In terms of precipitation, you can expect it to rain occasionally.
What to wear/what to pack:
-
Light skirts
-
Short pants or heavy shorts
-
Extra socks
-
Sunscreen lotion
-
Bug repellent
-
Long and short sleeve shirts
-
Light dresses
You can find some great options here
-
Sandals
-
Breathable footwear or sandals
-
Beach necessities
If you're going to the beach:
-
A rain jacket to layer with a coat
-
100% waterproof footwear
We recommend these rain boots:
-
Rain pants
These will be vital in a storm.
-
Waterproof phone bag
-
Wind resistant umbrella
This one is an excellent one to buy.
-
Waterproof bag/luggage cover
So your bags don't get wet. We recommend:
September
September here is mild. Temperatures average in the low 70s F (low 20s C) during the day. It rains regularly.
What to wear/what to pack:
-
Long and short sleeve shirts
-
Sunscreen lotion
-
Extra socks
-
Sandals
-
Breathable footwear or sandals
-
Short pants or heavy shorts
-
Bug repellent
-
Light skirts
-
Light dresses
You can find some great options here
-
Beach necessities
If you're going to the beach:
-
A rain jacket to layer with a coat
-
100% waterproof footwear
We recommend rain boots:
-
Rain pants
Rain pants are a lifesaver in a storm.
-
Waterproof phone bag
-
Windproof umbrella
This one is a great one to buy.
-
Waterproof bag/luggage cover
So your suitcases remain dry. We like:
October
If you go to Mercer Island in October, you will notice that it is cool and somewhat rainy. Expect it to rain about a third of the time. Daytime temperatures are in the low 50s F (mid 10s C).
What to wear/what to pack:
-
Long sleeve shirts or blouses
-
Light and heavy skirts
-
Standard footwear
-
Pants or jeans
-
Extra socks
-
Light jacket or fleece
-
Dresses
-
A rain jacket to layer with another jacket
-
100% waterproof footwear
We suggest rain boots:
-
Rain pants
Rain pants can be a lifesaver in a rainstorm.
-
Waterproof phone bag
-
Umbrella
This one is a perfect one to buy.
-
Waterproof bag/luggage cover
So your things stay dry. We suggest:
November
If you visit Mercer Island during November, you will probably notice that it is pretty cool and very rainy. Temperatures tend to hover around the low 50s F (low 10s C) during the day, while at night they can dip into the low 40s F (single digits C). In terms of precipitation, you can expect it to rain about half of the time.
What to wear/what to pack:
-
Long sleeve shirts or blouses
-
Extra socks
-
Dresses
-
Light and heavy skirts
-
Pants or jeans
-
Standard footwear
-
Light jacket or fleece
-
A rain poncho to layer with another jacket
-
100% waterproof footwear
We suggest rain boots:
-
Rain pants
Rain pants can be essential in a storm.
-
Waterproof phone bag
-
Windproof umbrella
This one is an excellent choice.
-
Waterproof bag/luggage cover
So your belongings remain dry. We like:
December
If you go to Mercer Island in December, you will notice that it can be brisk and very rainy. Expect it to rain about half of the time. Daytime temperatures are in the 40s F (single digits C).
What to wear/what to pack:
-
Warm pants or jeans
-
Fleece
-
Lip balm
In our opinion, the best option: this
-
Extra socks
-
Jacket or coat
-
Light gloves or mittens
-
Standard footwear
-
A rain coat to layer with a jacket
-
100% waterproof footwear
We recommend these rain boots:
-
Rain pants
Rain pants will be a lifesaver in a storm.
-
Waterproof phone bag
-
Wind resistant umbrella
This one is a great option.
-
Waterproof bag/luggage cover
So your things don't get wet. We suggest:
Activities for Mercer Island, Washington, United States of America
Here are some activity recommendations and activity-specific packing tips for Mercer Island.
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