The Kona side of the Big Island is arid and hot, with mile upon mile of black lava fields lining a shimmering coastline. The Hilo side, on the other hand, gets roughly 130 inches of rain a year, so the chances of getting rained on while driving along the Hamakua Coast to Hilo are pretty high. That said, it tends to rain in the morning on the Hilo side and clear up by afternoon, leaving a handful of rainbows behind.
You can see hump-back whales clearly off the western coast of the island from about January until May. Technically, whale season is from November to May, but the migration doesn't really get going until January. The few scattered sightings in November and December are usually young males showing off. The Merrie Monarch Festival brings a full week of hula, both ancient and modern, to Hilo, beginning the week after Easter. Fish stories abound in Kailua-Kona every August during the week-long Hawaiian International Billfish Tournament. The Ironman Triathlon takes place every October in Kailua-Kona. Consider volunteering -- you'll be inspired, and it's a great party.
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