Issued: Nov 22, 2014 2:30 AM HST
Based on data through 2:00 am Nov 22 2014 HST
The main Hawaiian islands continue to lie under an easterly trade wind flow south of a ridge along 28°N. Patches of rather stable, broken stratocumulus clouds moving along the trades are affecting windward slopes of the smaller islands, especially Maui. Stable stratocumulus clouds dominate over waters far east and northeast of the islands. The Big Island remains obscured by high clouds.
The shield of broken high clouds passing over the Big Island covers much of the region south of the state. A somewhat weak upper level trough stretches nearly east to west across the islands. Southwest to west flow aloft along the southern flank of the upper trough is tapping elevated moisture from deep convection in the ITCZ. High clouds generated from this moisture are being transported to the north and east. Thunderstorm activity within the ITCZ remains confined south of 10°N.
A front over the northwest Hawaiian islands is showing signs of a resumed eastward movement. The 175 mile-wide band band of broken low clouds marking the front has its leading from 30°N 163°W to near laysan island at 26°N 172°W, to 23°N 180°. To the north of the front, Midway atoll remains under a persistent area of broken to overcast stratocumulus, while a narrow band of broken high clouds is streaming overhead. These high clouds mark an upper level trough driving the front.