In 1941, Hawaii was a territory of the US with statehood some eighteen years away. As early because the 1870’s, the US army had scoped out the islands for industrial and defensive potential and determined that Pearly harbor on the south aspect of Oahu about ten miles northwest of Honolulu match the invoice. With the persistent commerce winds blowing from the northeast a lot of the yr, this explicit a part of Oahu is within the rain shadow of the Koolau Vary. Whereas clouds and rain are widespread within the Koolau Vary, the downsloping winds are likely to dry out for southern aspect of the island. In actual fact, Honolulu averages solely about 17 inches of rainfall in a given yr as a result of drying results of the downsloping winds.
Climate on December seventh
On the morning of December seventh, 1941, the climate observer at Hickam Subject in Honolulu reported primarily clear skies every hour with delicate temperatures and light-weight east-to-northeast winds. There was nothing that might hinder fighter pilots traces of sight, no heavy cloud cowl and no heavy rains to make flight troublesome on that fateful day. After crossing the tough waters of the North Pacific, the Japanese fighter pilots in additional than 350 planes reported seeing a “lengthy white line of coast” referring to Oahu’s Kakuku Level (in response to Nationwide Geographic, AccuWeather). In abstract, so far as the climate was involved, all was favorable for the assault that had been deliberate “many days and even weeks upfront” in response to President Roosevelt in his well-known speech given on the next day.