Bad weather allowed the Allied expeditionary force to arrive unseen by the Japanese on the night of 6 August and the following morning, taking the defenders by surprise. This is sometimes called the "Midnight Raid on Guadalcanal". A Japanese patrol aircraft from Tulagi had searched the general area the Allied invasion fleet was moving through, but missed seeing the Allied ships due to severe storms and heavy clouds. The landing force split into two groups, with one group assaulting Guadalcanal, and the other Tulagi, Florida, and nearby islands. Allied warships bombarded the invasion beaches, while U.S. carrier aircraft bombed Japanese positions on the target islands and destroyed 15 Japanese seaplanes at their base near Tulagi.