2025 Compare Climate & Weather:
Castaic, CA vs Hilo, HI

Highlights

On average, there are 175 sunny days per year in Hilo. Castaic averages 283 sunny days per year. The US average is 205 sunny days.

Hilo, Hawaii gets 143.1 inches of rain, on average, per year. Castaic, California gets 18.4 inches of rain, on average, per year. The US average is 38.1 inches of rain per year.

Hilo averages 0 inches of snow per year. Castaic averages 0 inches of snow per year. The US average is 27.8 inches of snow per year.

Weather Highlights

Hilo, Hawaii
Summer High: the July high is around 81 degrees
Winter Low: the January low is 63
Rain: averages 143.1 inches of rain a year
Snow: averages 0 inches of snow a year

Castaic, California
Summer High: the July high is around 89.8 degrees
Winter Low: the January low is 46.1
Rain: averages 18.4 inches of rain a year
Snow: averages 0 inches of snow a year

BestPlaces Comfort Index

The annual BestPlaces Comfort Index for Hilo is 8.6 (10=best), which means it is less comfortable than most places in Hawaii.

The annual BestPlaces Comfort Index for Castaic is 8.9 (10=best), which means it is more comfortable than most places in California.

Today's Weather - Castaic, CA

57°F

Today's Weather - Hilo, HI

66°F

Average Monthly High / Low (°F)

Hot, Freezing, Rainy, Snowy Days: Castaic / Hilo

August is the hottest month for Castaic with an average high temperature of 91.4°, which ranks it as about average compared to other places in California. In Castaic, there are 5 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Castaic are May, October and June.

September is the hottest month for Hilo with an average high temperature of 81.7°, which ranks it as cooler than most places in Hawaii. In Hilo, there are 12 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Hilo are December, April and March.

December has the coldest nighttime temperatures for Castaic with an average of 45.8°. This is one of the warmest places in California.

February has the coldest nighttime temperatures for Hilo with an average of 62.8°. This is about average compared to other places in Hawaii.

In Castaic, there are 63.4 days annually when the high temperature is over 90°, which is about average compared to other places in California.

In Hilo, there are 0.0 days annually when the high temperature is over 90°, which is cooler than most places in Hawaii.

In Castaic, there are 0.6 days annually when the nighttime low temperature falls below freezing, which is one of the warmest places in California.

In Hilo, there are 0.0 days annually when the nighttime low temperature falls below freezing, which is one of the coldest places in Hawaii.

In Castaic, there are 0.0 days annually when the nighttime low temperature falls below zero°, which is about average compared to other places in California.

In Hilo, there are 0.0 days annually when the nighttime low temperature falls below zero°, which is about average compared to other places in Hawaii.

February is the wettest month in Castaic with 4.4 inches of rain, and the driest month is July with 0.0 inches. The wettest season is Spring with 61% of yearly precipitation and 1% occurs in Autumn, which is the driest season. The annual rainfall of 18.4 inches in Castaic means that it is about average compared to other places in California.


November is the wettest month in Hilo with 15.9 inches of rain, and the driest month is June with 8.4 inches. The wettest season is Winter with 27% of yearly precipitation and 22% occurs in Autumn, which is the driest season. The annual rainfall of 143.1 inches in Hilo means that it is one of the wettest places in Hawaii.

February is the rainiest month in Castaic with 6.4 days of rain, and July is the driest month with only 0.3 rainy days. There are 34.1 rainy days annually in Castaic, which is less rainy than most places in California. The rainiest season is Spring when it rains 49% of the time and the driest is Autumn with only a 4% chance of a rainy day.

April is the rainiest month in Hilo with 21.9 days of rain, and February is the driest month with only 14.9 rainy days. There are 235.8 rainy days annually in Hilo, which is rainier than most places in Hawaii. The rainiest season is Autumn when it rains 27% of the time and the driest is Spring with only a 21% chance of a rainy day.

There is rarely any recorded snowfall in Castaic, ranking it as one of the least snowy places in California.

There is rarely any recorded snowfall in Hilo, ranking it as one of the least snowy places in Hawaii.

Any measurable snowfall is a rare occurance in Castaic.

Any measurable snowfall is a rare occurance in Hilo.