Weather in Waimanalo, Hawaii
Flowers spill across the islands. Day 59 of spring. Read this microseason across nine climate regions →
- TodayMay 16Heavy Drizzle33%79°73°
- SundayMay 17Light Drizzle—80°73°
- MondayMay 18Drizzle17%78°73°
- TuesdayMay 19Light Drizzle14%80°74°
- WednesdayMay 20Light Rain41%78°73°
- ThursdayMay 21Light Drizzle33%78°74°
- FridayMay 22Light Drizzle22%77°72°
- PM 2.5
- 4.2 μg/m³
- PM 10
- 7.1 μg/m³
- NO₂
- 0.6 μg/m³
- Ozone
- 55.0 μg/m³
- UV Index
- 0.3 Low
When the dew is on the grass, rain will never come to pass.
- Moonrise
- 4:27 PM
- Moonset
- 5:29 AM
- In sign
- ♊︎ Gemini
Flowers spill across the islands
Waimanalo at a glance
- Today vs. normal: 17°F below the seasonal normal for this latitude
- Last frost: December 25 (climatological average for this latitude)
- Microseason: 28 of 72, May 16–20
- Planting window: Direct sow okra, melons, and southern peas. Thin carrot rows.
Right now in the garden
Peak growing season
As of May 17, the growing season is at its peak — frost is months away. Continue succession-planting beans and summer squash. Start fall brassicas (broccoli, cabbage, kale) from seed indoors for transplanting in late summer.
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| January | — | — |
| February | lettuce, peas, spinach, radishes | — |
| March | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | — |
| April | tomatoes, peppers, beans, squash | — |
| May | tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| June | — | lettuce, peas, radishes |
| July | — | tomatoes, beans, summer squash |
| August | — | tomatoes, beans, summer squash |
| September | — | tomatoes, beans, summer squash |
| October | fall brassicas, garlic (overwinter), carrots | winter squash, tomatoes (last) |
| November | fall brassicas, garlic (overwinter), carrots | — |
| December | — | — |
A year in weather
Waimanalo's warmest month is September (~75°F mean) and its coldest is February (~70°F). Rainfall peaks in July (15.3 inches) and bottoms out in February (9.1 inches).
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 70° | 10.6″ | 12 |
| February | 70° | 9.1″ | 12 |
| March | 70° | 13.7″ | 15 |
| April | 71° | 12.9″ | 18 |
| May | 72° | 9.3″ | 16 |
| June | 73° | 12.9″ | 21 |
| July | 74° | 15.3″ | 23 |
| August | 75° | 12.7″ | 20 |
| September | 75° | 12.2″ | 19 |
| October | 75° | 12.9″ | 19 |
| November | 73° | 15.1″ | 18 |
| December | 71° | 14.2″ | 18 |
Regional context
Waimanalo sits within a varied climate region — a cohort that shares similar temperature ranges, seasonal patterns, and growing conditions across nearby cities.
Similar climates: Honolulu, HI, Kailua, HI, East Honolulu, HI, Hilo, HI, Pearl City, HI.
Frequently asked
- When does it freeze in Waimanalo?
- Waimanalo's last spring frost typically falls around mid-February, and the first fall frost arrives around mid-December.
- What is the rainy season in Waimanalo?
- July is the wettest month with about 15.3 inches of rain on average; the city receives roughly 151 inches annually.
- What is the warmest month in Waimanalo?
- September is typically warmest, averaging about 75°F.
- What is the coldest month in Waimanalo?
- February is typically coldest, averaging about 70°F.
- When can I start a vegetable garden in Waimanalo?
- Cool-season crops (peas, lettuce) can be sown around the last spring frost (mid-February); warm-season crops (tomatoes, peppers) wait until 1–2 weeks after.
- How many rainy days does Waimanalo get?
- Waimanalo averages about 210 rainy days per year.
- What hardiness zone is Waimanalo?
- Waimanalo's USDA hardiness zone is determined by its lowest average winter temperature; check the USDA's online lookup with the city ZIP for the current zone designation.
Climate
Waimanalo, Hawaii sits in a varied climate zone. January means hover near 70°F while July averages 74°F — a 5°F seasonal swing.
Across the year, Waimanalo receives about 151 inches of precipitation spread over roughly 210 rainy days.
The rhythm of the year is set by latitude (21.3°N), proximity to large water bodies, and elevation — all of which shape what grows here, when frost is likely, and what the weather story looks like day to day.