Issued: Dec 08, 2013 2:30 PM HST
Based on data through 2:00 pm Dec 08 2013 HST
A narrow and nearly stationary upper trough remained near the Big Island this afternoon. The trough axis stretched from a relatively weak upper low near 26°N 150°W across the Alenuihaha channel to 14°N 160°W to 07°N 163°W. Widely separated, isolated thunderstorms were forming along the trough.
Another upper level trough moving rapidly from the west was over Kauai. The axis of this trough stretched from 26°N 159°W to 18°N 162°W. This trough had slowed since this morning and was moving eastward near 35 miles an hour. Isolated thunderstorms were this trough as well. With two upper trough near the islands, the air mass remained fairly unstable with thunderstorms around both ends of the island chain.
Just further to the northwest, a front stretched southwest through 30°N 162.5°W through 24°N 170°W to beyond 21°N 180°E. The fairly narrow, 60 to 75 miles wide, associated cloud band, was moving east at 15 to 20 miles an hour. The band consisted of broken to overcast low clouds with less than a handful of thunderstorms along it. A low pressure system associated with the front was centered near 33°N 165°W and was moving toward the northeast.
A convergence cloud band between the front and Kauai did, however, contain a few more thunderstorms. The narrow band of clouds along this low level pre-frontal convergence zone stretched from 28°N 161°W to 18°N 169°W.
At 2 pm, Kauai was cloudy to mostly cloudy due to broken to overcast low clouds overhead. The Big Island was nearly completely covered by overcast clouds, a mix of low, mid and high level clouds. Parts of east Maui were mostly cloudy. But Oahu and the rest of Maui county were sunny to mostly sunny. Low clouds in the vicinity of the islands were moving northwest at just over 20 miles an hour.