Mililani, HI climate
Mililani has warm winters and pleasant summers, with plenty of rain. A typical July afternoon reaches 82°, a January night drops to 61°, and snow is almost unheard of.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Mililani feels like
Winter
Spring
Summer
Fall
Mililani weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground |
|---|---|---|---|---|---|---|
| January | 76° | 61° | 5.2" | 0 | 17 | 0 |
| February | 76° | 60° | 4.3" | 0 | 15 | 0 |
| March | 77° | 62° | 6.3" | 0 | 17 | 0 |
| April | 77° | 63° | 5.6" | 0 | 22 | 0 |
| May | 79° | 65° | 4.3" | 0 | 18 | 0 |
| June | 80° | 67° | 4.2" | 0 | 22 | 0 |
| July | 82° | 67° | 5.2" | 0 | 23 | 0 |
| August | 83° | 68° | 4.0" | 0 | 20 | 0 |
| September | 83° | 67° | 4.6" | 0 | 19 | 0 |
| October | 82° | 66° | 5.8" | 0 | 22 | 0 |
| November | 79° | 65° | 7.1" | 0 | 22 | 0 |
| December | 77° | 63° | 7.5" | 0 | 20 | 0 |
| Year | 79° | 64° | 64.1" | 0.0" | 237 | 0 |
“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more.
Rain and snow in Mililani
Mililani gets 64 inches of rain and melted snow a year. December is the wettest month and August the driest. Rain or snow falls on about 237 days a year.
A year-round growing season
Heating and cooling a home in Mililani
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Mililani, 0% of that work is heating and 100% is cooling, so air conditioning is the bigger bill.
Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.
How Mililani compares
Compared with every U.S. town and city on TownTapestry, each counted once.
Common questions about Mililani’s climate
What is the coldest month in Mililani?
February, with a typical high of 76° and a low of 60°.
What is the hottest month in Mililani?
September, with a typical high of 83° and a low of 67°.
How much snow does Mililani get?
Almost none. A normal year brings 0.0 inches.
When is the first frost in Mililani?
Frost is uncommon. Only 0% of years see a night at 32° or below.
What is the rainiest month in Mililani?
December, with 7.5 inches of rain and melted snow. The year totals 64 inches.
NOAA’s gridded normals don’t cover this state, so temperatures and rainfall come from the nearest weather station. Snow, frost dates and day counts come from NOAA’s weather station at Upper Wahiawa 874.3, HI (4 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020.