O'Fallon, Illinois, United States of America: What to pack, what to wear, and when to go [2022]
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Traveling to O'Fallon, Illinois, United States of America? If you're planning to go to O'Fallon, this is some important information about when to go, what to wear, and what to pack.
Contents
- When to go to O'Fallon
- Important essentials for O'Fallon
- Activities for O'Fallon
- O'Fallon in January: weather and what to pack
- O'Fallon in February: weather and what to pack
- O'Fallon in March: weather and what to pack
- O'Fallon in April: weather and what to pack
- O'Fallon in May: weather and what to pack
- O'Fallon in June: weather and what to pack
- O'Fallon in July: weather and what to pack
- O'Fallon in August: weather and what to pack
- O'Fallon in September: weather and what to pack
- O'Fallon in October: weather and what to pack
- O'Fallon in November: weather and what to pack
- O'Fallon 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 O'Fallon, Illinois, United States of America
Based on the climate and weather in O'Fallon, the best time to go is September. See below for details.
Important essentials for O'Fallon, Illinois, United States of America
Here are some general tips on what to wear in O'Fallon, as well as several items to remember to pack when traveling there.
COVID-19 ESSENTIALS FOR 2022
-
N95 masks to use in crowded airports
These N95 masks provide the best level of protection possible.
-
Kids' KN95 masks
N95 masks don't exist for kids. These are a good alternative (and can also be used by adults if N95 masks are not available).
-
Hand sanitizer
This hand sanitizer is an easy-to-carry plane-friendly product.
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.
-
A vaccine card protector
Vaccine cards frequently wear out. An unreadable card may result in severe consequences. This vaccine card protector helps stop that.
General health necessities
Don't forget these
-
Voice and data SIM card
A SIM card that works in O'Fallon. 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 be appropriate for most locations, but you should check with your hotel.
-
Airplane or car necessities
-
Power bank for devices
A portable power bank, like this one
-
For families with young children
-
Money/passport pouch
A money pouch is vital for protecting your passport and credit cards.
What to wear/what to pack for O'Fallon, Illinois, United States of America by month
Already know when you're traveling?
January
January in O'Fallon is cold. The average overnight temperatures in the area are in the low 20s F (single digits below 0 C). It tends to rain 5-10 days this month. It also snows sometimes. But the colder weather doesn't bring low humidity, which is in the 50% to 60% range on average.
What to wear/what to pack:
-
Sweaters
-
Heavy jacket
-
Warm pants or jeans
-
Heavy socks
Such as:
-
Lip balm
Our pick: this one
-
Gloves
-
Insulated water bottle
Our fave:
-
Cold weather footwear
-
A rain coat to layer with a coat
-
100% waterproof footwear
We use rain boots:
-
Rain pants
Rain pants are essential in heavy rain.
-
Waterproof phone bag
-
Windproof umbrella
This one is an excellent one to buy.
-
Waterproof bag/luggage cover
So your suitcases stay dry. We like:
February
If you go to O'Fallon in February, you will notice that it can be brisk. Expect it to rain 5-10 days this month. Daytime temperatures are in the 40s F (single digits C).
What to wear/what to pack:
-
Lip balm
Our pick is: this one
-
Sweaters
-
Gloves
-
Insulated water bottle
Our first choice:
-
Warm pants or jeans
-
Heavy jacket
-
Heavy socks
Such as:
-
Cold weather footwear
-
A rain coat to layer with a coat
-
100% waterproof footwear
We recommend rain boots:
-
Rain pants
Rain pants are vital in a rainstorm.
-
Waterproof phone bag
-
Windproof umbrella
This one is a great one to buy.
-
Waterproof bag/luggage cover
So your belongings stay dry. We like:
March
If you visit O'Fallon during March, you may see that it is cool and somewhat rainy. Temperatures tend to hover around the 50s F (low 10s C) during the day, while at night they can dip into the low 30s F (single digits C). Humidity is generally between 50 and 60% during the day. In terms of precipitation, you can expect it to rain 5-10 days this month.
What to wear/what to pack:
-
Jacket or coat
-
Light gloves or mittens
-
Lip balm
In our opinion, the best is: here
-
Extra socks
-
Warm pants or jeans
-
Fleece
-
Standard footwear
-
Rain poncho
A durable rain poncho to wear over your coat will help avoid loads of aggrevation by protecting your coat. We like this one.
-
The stormy weather makes rubber rain boots essential. These boots are well-suited for stormy weather:
-
An umbrella
This excellent one is made for bad weather.
-
Waterproof luggage cover
So your belongings don't get wet. Even the best luggage can let water in. We recommend:
-
Rain pants
These will be essential in a rainstorm.
April
April for O'Fallon is balmy and somewhat rainy. Temperatures average in the high 60s F (high 10s C) during the day. It rains regularly.
What to wear/what to pack:
-
Light and heavy skirts
-
Dresses
-
Standard footwear
-
Long sleeve shirts or blouses
-
Light jacket or fleece
-
Pants or jeans
-
Extra socks
-
Rain poncho
A good rain poncho to wear over your coat saves you time and money by protecting your nice coat. We like this one.
-
Stormy weather makes rubber rain boots essential. These boots work well for stormy weather:
-
An umbrella
This excellent one is made for storms.
-
Waterproof luggage cover
So your stuff stay dry. The finest suitcases can let water in. We like:
-
Rain pants
Rain pants are essential in a rainstorm.
May
May in this region is a perfect temperature and somewhat rainy. Temperatures average in the 70s F (mid 20s C) during the day. It rains a bit less than half of the time.
What to wear/what to pack:
-
Short pants or heavy shorts
-
Sandals
-
Sunscreen lotion
-
Bug repellent
-
Light skirts
-
Extra socks
-
Light dresses
You can find some great options here
-
Breathable footwear or sandals
-
Long and short sleeve shirts
-
Rain poncho
A good rain poncho to wear over your jacket will avoid travel headaches by protecting your nice coat. We like this one.
-
Stormy weather makes rubber rain boots a must. These boots work well for stormy weather:
-
An umbrella
This excellent one is built for storms.
-
Waterproof luggage cover
So your things don't get wet. Even the finest luggage can let rain in. We suggest:
-
Rain pants
These are a lifesaver in a rainstorm.
June
If you go to O'Fallon in June, you will notice that it is pretty consistently hot. Expect it to rain a bit less than half of the time. Daytime temperatures are in the 80s F (high 20s C).
What to wear/what to pack:
-
Insulated water bottle
Our first choice also removes dangerous contaminants:
-
Sunscreen lotion, moderate SPF
-
Waterproof sandals
-
Cool and dry dresses
These dresses to provide UV protection and cool you.
-
Sunglasses
-
Skirts
-
Loose-fit shorts
-
Breatheable shirts
A cooling shirt can keep you cool and guard against skin damage:
-
Bug repellent
-
Rain poncho
A quality rain poncho to wear over your jacket saves you time and money by protecting your coat. We like this one.
-
Stormy weather makes rubber rain boots a necessity. These boots work well for stormy weather:
-
An umbrella
This excellent one is made for bad weather.
-
Waterproof luggage cover
So your stuff remain dry. The best suitcases can let water in. We suggest:
-
Rain pants
These are vital in a storm.
July
If you go to O'Fallon in July, you will notice that it is really hot. Expect it to rain a bit less than half of the time. Daytime temperatures are in the high 80s F (low 30s C).
What to wear/what to pack:
-
Insulated water bottle
Our pick also removes contaminants:
-
Sunscreen lotion, moderate SPF
-
Breatheable shirts
A breatheable shirt can make you comfortable and guard against UV rays:
-
Bug repellent
-
Cool and dry dresses
These dresses offer UV protection and cool you.
-
Sunglasses
-
Waterproof sandals
-
Loose-fit shorts
-
Skirts
-
Rain poncho
A good rain poncho to wear over your coat saves you time and money by protecting your main jacket. We like this one.
-
Stormy weather makes rubber rain boots a must. These boots are well-suited for stormy weather:
-
An umbrella
This excellent one is designed for bad weather.
-
Waterproof luggage cover
So your belongings don't get wet. The most durable luggage can let moisture in. We recommend:
-
Rain pants
Rain pants can be a lifesaver in heavy rain.
August
If you are traveling to O'Fallon in August, you will notice that it is consistently hot. Expect it to rain a bit less than half of the time. Daytime temperatures are in the high 80s F (low 30s C).
What to wear/what to pack:
-
Waterproof sandals
-
Insulated water bottle
Our choice also filters dangerous contaminants:
-
Skirts
-
Cool and dry dresses
These dresses include UV protection and help you stay cool.
-
Sunglasses
-
Bug repellent
-
Breatheable shirts
A breatheable shirt can keep you cool and protect you from UV rays:
-
Sunscreen lotion, moderate SPF
-
Loose-fit shorts
-
Rain poncho
A durable rain poncho to wear over your coat can be a lifesaver by protecting your nice coat. We like this one.
-
Stormy weather makes rubber rain boots a must. These boots are well-suited for stormy weather:
-
An umbrella
This excellent one is designed for bad weather.
-
Waterproof luggage cover
So your things remain dry. Even the best luggage can let rain in. We suggest:
-
Rain pants
Rain pants are vital in a rainstorm.
September
September in O'Fallon is hot. Temperatures average in the low 80s F (high 20s C) during the day. It rains 5-10 days this month.
What to wear/what to pack:
-
Breathable footwear or sandals
-
Bug repellent
-
Sunscreen lotion
-
Extra socks
-
Sandals
-
Short pants or heavy shorts
-
Long and short sleeve shirts
-
Light dresses
You can find some great options here
-
Light skirts
-
Rain poncho
A weatherproof rain poncho to wear over your jacket will avoid travel headaches by protecting your nice coat. We like this one.
-
Rainy weather makes rubber rain boots a must. These boots work well for stormy weather:
-
An umbrella
This excellent one is made for storms.
-
Waterproof luggage cover
So your stuff don't get wet. Even the best suitcases can let rain in. We recommend:
-
Rain pants
These are a lifesaver in heavy rain.
October
October in O'Fallon is balmy. The average overnight temperatures in the area are in the 40s F (single digits C), with a few days below 32 F (single digits C). It tends to rain 5-10 days this month. With the colder weather comes lower humidity, which is in the 50% to 60% range on average.
What to wear/what to pack:
-
Standard footwear
-
Extra socks
-
Pants or jeans
-
Dresses
-
Light and heavy skirts
-
Long sleeve shirts or blouses
-
Light jacket or fleece
-
Rain poncho
A good rain poncho to wear over your coat can be a lifesaver by protecting your main jacket. We like this one.
-
The stormy weather makes rubber rain boots a necessity. These boots work well for stormy weather:
-
An umbrella
This excellent one is made for bad weather.
-
Waterproof luggage cover
So your belongings stay dry. The best suitcases can let water in. We like:
-
Rain pants
These pants can be a lifesaver in heavy rain.
November
November in O'Fallon is cool. The average overnight temperatures in the area are in the 30s F (single digits C). It tends to rain regularly. But the colder weather doesn't bring low humidity, which is in the 50% to 60% range on average.
What to wear/what to pack:
-
Fleece
-
Jacket or coat
-
Lip balm
In our opinion, the best option: this
-
Extra socks
-
Warm pants or jeans
-
Light gloves or mittens
-
Standard footwear
-
A rain coat to layer with a jacket
-
100% waterproof footwear
We recommend rain boots:
-
Rain pants
These pants can be essential in a storm.
-
Waterproof phone bag
-
Wind resistant umbrella
This one is an excellent one to buy.
-
Waterproof bag/luggage cover
So your suitcases don't get wet. We recommend:
December
If you go to O'Fallon in December, you will notice that it is pretty cool. Expect it to rain regularly. Daytime temperatures are in the low 40s F (single digits C).
What to wear/what to pack:
-
Gloves
-
Heavy jacket
-
Sweaters
-
Heavy socks
Such as:
-
Insulated water bottle
Our best choice:
-
Warm pants or jeans
-
Lip balm
Our choice: here
-
Cold weather footwear
-
A rain jacket to layer with a coat
-
100% waterproof footwear
We like rain boots:
-
Rain pants
Rain pants can be vital in a storm.
-
Waterproof phone bag
-
Wind resistant umbrella
This one is a great option.
-
Waterproof bag/luggage cover
So your things stay dry. We like:
Activities for O'Fallon, Illinois, United States of America
Here are some activity recommendations and activity-specific packing tips for O'Fallon.
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