Ontario, California, United States of America: What to pack, what to wear, and when to go [2018]

Traveling to Ontario, California, United States of America? If you're planning to go to Ontario, here is some important information about when to go, what to wear, and what to pack:

When to go to Ontario, California, United States of America

Based on the climate and weather in Ontario, the best time to go is May. See below for details.

What to wear/what to pack for Ontario, California, United States of America by month

January

If you vacation in Ontario during January, you are likely to find that it is mild. Temperatures tend to hover around the 60s F (high 10s C) during the day, while at night they can dip into the 40s F (single digits C).

Humidity is generally between 40 and 50% during the day.

What to wear/what to pack:

  • Dresses
  • Standard footwear
  • Pants or jeans
  • Long skirts
  • Socks
  • Light jacket or fleece
  • Long sleeve shirts or blouses

February

If you are traveling to Ontario in February, you will notice that it is mild. Daytime temperatures are in the 60s F (high 10s C).

What to wear/what to pack:

  • Standard footwear
  • Pants or jeans
  • Dresses
  • Light jacket or fleece
  • Long sleeve shirts or blouses
  • Socks
  • Long skirts

March

If you vacation in Ontario during March, you are likely to find 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 high 40s F (single digits C).

Humidity is generally between 50 and 60% during the day.

What to wear/what to pack:

  • Socks
  • Dresses
  • Light jacket or fleece
  • Long skirts
  • Long sleeve shirts or blouses
  • Pants or jeans
  • Standard footwear

April

If you vacation in Ontario during April, you are likely to find that it is warm. Temperatures tend to hover around the 70s F (low 20s C) during the day, while at night they can dip into the low 50s F (low 10s C).

Humidity is generally between 40 and 50% during the day.

What to wear/what to pack:

  • Sandals
  • Skirts
  • Shorts or short pants
  • Light footwear
  • Dresses
  • Long and short sleeve shirts
  • Sunscreen lotion

May

If you vacation in Ontario during May, you are likely to find that it is a perfect temperature. Temperatures tend to hover around the high 70s F (mid 20s C) during the day, while at night they can dip into the 50s F (low 10s C).

Humidity is generally between 40 and 50% during the day.

What to wear/what to pack:

  • Long and short sleeve shirts
  • Light footwear
  • Shorts or short pants
  • Skirts
  • Sandals
  • Dresses
  • Sunscreen lotion

June

If you visit Ontario during June, you are likely to find that it is constantly hot. Temperatures tend to hover around the 80s F (low 20s C) during the day, while at night they can dip into the high 50s F (mid 10s C).

Humidity is generally between 40 and 50% during the day.

What to wear/what to pack:

  • Short sleeve shirts
  • Sunscreen lotion
  • Sunglasses
  • Shorts
  • Skirts
  • Dresses
  • Sandals

July

If you are traveling to Ontario in July, you will notice that it is a scorcher. Daytime temperatures are in the low 90s F (low 30s C).

What to wear/what to pack:

  • Sunglasses
  • Skirts
  • Light shorts
  • Sandals
  • Light dresses
  • Tank tops
  • High-SPF sunscreen lotion
  • Thin pants, such as light khakis
  • Thin short sleeve shirts

August

If you visit Ontario during August, you are likely to find that it can be blisteringly hot. Temperatures tend to hover around the 90s F (mid 30s C) during the day, while at night they can dip into the 60s F (high 10s C).

Humidity is generally between 30 and 40% during the day.

What to wear/what to pack:

  • Tank tops
  • Thin pants, such as light khakis
  • High-SPF sunscreen lotion
  • Thin short sleeve shirts
  • Light dresses
  • Sandals
  • Sunglasses
  • Skirts
  • Light shorts

September

If you are traveling to Ontario in September, you will notice that it is constantly hot. Daytime temperatures are in the high 80s F (low 30s C).

What to wear/what to pack:

  • Skirts
  • Sandals
  • Sunglasses
  • Shorts
  • Sunscreen lotion
  • Short sleeve shirts
  • Dresses

October

If you vacation in Ontario during October, you are likely to find that it is pretty consistently hot. Temperatures tend to hover around the low 80s F (high 20s C) during the day, while at night they can dip into the 50s F (low 10s C).

Humidity is generally between 40 and 50% during the day.

What to wear/what to pack:

  • Sunscreen lotion
  • Sandals
  • Skirts
  • Long and short sleeve shirts
  • Shorts or short pants
  • Light footwear
  • Dresses

November

If you are traveling to Ontario in November, you will notice that it is balmy. Daytime temperatures are in the low 70s F (low 20s C).

What to wear/what to pack:

  • Sunscreen lotion
  • Sandals
  • Light footwear
  • Skirts
  • Dresses
  • Shorts or short pants
  • Long and short sleeve shirts

December

If you visit Ontario during December, you are likely to find that it is balmy. Temperatures tend to hover around the 60s F (high 10s C) during the day, while at night they can dip into the low 40s F (single digits C).

Humidity is generally between 40 and 50% during the day.

What to wear/what to pack:

  • Dresses
  • Long sleeve shirts or blouses
  • Socks
  • Light jacket or fleece
  • Standard footwear
  • Long skirts
  • Pants or jeans

Year-round what to wear/what to pack for Ontario, California, United States of America

Here are some general tips on what to wear in Ontario, as well as several items to remember to pack when traveling there.

  • A plug adadpter that supports outlet types A and B
  • A SIM card that works in Ontario
  • Appropriate museum wear

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