Climate and monthly weather forecast
Waimea Canyon State Park, HI

Waimea Canyon State Park, positioned in the unique tropical location of Hawaii, USA, encounters what is familiarly known as the tropical monsoon climate. According to the Köppen climate classification, this is prominently known as the Am climate. The tropical monsoon climate represents a fine balance between temperature and rainfall throughout the year.

On a monthly average basis, the ocean temperature fluctuates narrowly from 75.4°F (24.1°C) occurring in March to a maximum of 80.5°F (26.9°C) in September—evidence of the Pacific Ocean's mitigating influence on the local climate. These water temperatures provide a highly conducive environment for marine life to thrive while simultaneously influencing atmospheric conditions around the coastline.

More universally, daylight hours display a definite annual pattern, with an increase between January (11 hours) to June (13.5 hours), and a gradual decline thereafter to December (10.8 hours). This shift in the duration of sunlight can place a profound impact on the overall climate of the park, particularly influencing its biodiversity.

This region's unique climate pattern can be visible in the levels of precipitation across the various months. The common denominator of the tropical monsoon climate, a substantial amount of rainfall, is distinctly present throughout the year.

Given the perpetual tropical monsoon climate, there isn't a definitive 'best' season to visit Waimea Canyon State park. Preference largely depends on the individual's comfort with warm temperatures and occasional, potentially heavy, rainfall. However, those with a preference for longer daylight hours and slightly higher ocean temperatures may find the period from June to August more to their tastes.

Designating the 'worst' time to visit Waimea Canyon State Park, given its continually warm temperatures and frequent rainfall, can be quite subjective. Some may find the slightly lower ocean temperatures and shorter daylight duration from January to March less appealing, especially those intending to partake in a variety of outdoor activities, including swimming and hiking.

Spring, roughly spanning from March to May in Waimea Canyon State Park, exhibits a gradual increase in ocean temperatures, rising from 75.4°F (24.1°C) in March to 79.3°F (26.3°C) in May. The daylight hours also display a growth, ranging from 12 hours in March to 13.2 hours in May. These conditions indicate the influx of the warmer season and an enhanced opportunity to explore the state park.

From June to August, Summer temperatures in the park continue the upward trend. Ocean temperatures peak at 80.5°F (26.9°C) in September, a sign of the summer's warm embrace. With daylight hours soaring to their maximum at 13.5 hours in June, there is ample opportunity for exploration and outdoor recreation throughout the summer months.

Autumn, rolling in from September to November, experiences a slight dip in ocean temperatures, declining from 80.5°F (26.9°C) in September to 78.7°F (25.9°C) in November. However, these temperatures still provide the perfect conditions for engaging in aquatic activities. Daylight hours also begin to reduce, settling down from 12.3 hours in September to 11.1 hours come November.

Throughout the Winter months—December to February—the park witnesses a further slump in both ocean temperature and daylight hours. Ocean temperatures range from 76.8°F (24.9°C) in December to a year-low of 75.4°F (24.1°C) in February. Concurrently, daylight hours are at their lowest, averaging at just 10.8 hours in December. Despite these drops, Winter in the park continues to boast satisfactory conditions for outdoor enjoyment.

The commencement of the year at Waimea Canyon State Park, Hawaii, brings forth weather marked by moderate sea temperatures and minimal daylight hours. Notable, January sees the sea temperature linger at 76.8°F (24.9°C), setting the tone for the year. Weather in January »

A noticeable shift in February's weather at the State Park can be observed, primarily due to lengthier days and slightly cooler sea temperatures. Witness the daylight extend to 11.4 hours, a pleasant increment compared to January. Weather in February »

March, at the park, registers a slight increase in daylight hours coupled with marginal decrease in sea temperature. Sea temperatures cool down to 75.4°F (24.1°C) in March, resonating with the transition towards spring. Longer daylight hours amounting to 12 hours afford ample time for outdoor activities and exploration of the park's vast landscape. Weather in March »

April's climatological course in Hawaii shows minute increments in daylight hours and reversal in the sea temperature trend. Sea temperature rises once again, reaching 76.7°F (24.8°C), signaling the beginning of warm days. The extended daylight of 12.7 hours invites visitors to explore the park and its wildlife for longer durations. Weather in April »

As summer looms closer, May at the Waimea Canyon State Park experiences warmer sea temperatures and longer sunlit days. The sea reflects warm temperatures hitting a significant 78.1°F (25.6°C), suggestive of the upcoming summer season. Weather in May »

June in Hawaii brings about the summer season characterized by slightly warmer sea temperatures and maximized daylight hours. This month greets the highest average daylight hours of 13.5, paired with rising sea temperatures hitting 79.3°F (26.3°C). Weather in June »

July witnesses only nominal changes from June's weather conditions at Hawaii's state park. With daylight hours slightly decreased to 13.3 and a minor increase in sea temperature reaching 79.2°F (26.2°C), July sustains the balmy climate. Weather in July »

August in Waimea Canyon State Park experiences minor weather modifications, with a marginal increase in sea temperatures and a slight decrease in sunlight. Sea temperature escalates to 79.8°F (26.6°C), the highest recorded throughout the year. Weather in August »

September signals a gradual transition towards autumn accompanied by falling daylight hours and increased sea temperatures. In this month, the highest sea temperature of 80.5°F (26.9°C) is noted, at the tail end of the summer. Weather in September »

October at the park sees a downward trend in both sea temperatures and daylight hours, signaling the onset of autumn. The sea temperatures being to cool, averaging around 79.9°F (26.6°C), a change evident from the previous month. Weather in October »

November continues the downward trending weather sequence observed in the late autumnal period in Hawaii. Sea temperatures keep falling, with an average of 78.7°F (25.9°C) noted for November. The earlier part of the day sees steady sunlight with the daylight ticking at 11.1 hours. Weather in November »

Concluding the year, December in Waimea Canyon State Park, Hawaii, sees the shortest daylight hours and a significant drop in sea temperatures. The sea temperatures lower further to a cool 76.8°F (24.9°C), mimicking the conditions from the beginning of the year. Weather in December »