Issued: Feb 26, 2015 7:30 PM HST
Based on data through 7:00 pm Feb 26 2015 HST
Water vapor images showed a broad but shallow area of low pressure in the middle atmosphere centered near 19°N 149°W. Lower clouds passing under this area grew and developed into towering cumuli within 240 miles of the point 20°N 150°W. More significant thunderstorms and towering cumuli developed along the east through southeast edge of this feature within 60 miles of the curve from 19°N 145°W to 13°N 142°W to 09°N 147°W. Layered middle to high debris clouds from this convection mostly obscured lower features east of the curve from 19°N 140°W to 22°N 146°W to 18°N 147°W to 15°N 145°W to 16°N 149°W to 11°N 149°W to 06°N 144°W to 09°N 140°W. Middle cloud layers forming along the northeast edge of this low mostly to partly obscured lower features within 120 miles of the curve from 30°N 146°W to 27°N 150°W to 22°N 140°W.
To the northwest, a nearly stationary band of middle to low cloud layers associated with a weakening front extended across Hawaiian waters within 75 miles of the curve from 30°N 162°W to 23°N 165°W to 15°N 180 and further north and southwest. Middle to high cloud layers separating from the main band obscured lower features mostly to completely north of the curve from 30°N 155°W to 23°N 158°W to 22°N 160°W to 22°N 162°W to 25°N 160°W to 30°N 163°W, and also partly to mostly within 130 miles of the curve from 30°N 154°W to 23°N 155°W to 16°N 166°W to 15°N 177°W and further north. Densely packed cold-air cumuli prevailed to the northwest of the main band, merging locally into areas of nearly solid low to middle overcast.
To the south, light thunderstorm activity continued in the ITCZ from 07°N to the equator, mainly from 170°W to 150°W. Layered middle to high debris clouds from this and earlier convection partly to mostly obscured lower features from 11°N to 01°N.
Otherwise, cloud cover across Hawaiian waters consisted mainly of large clumps of low to middle cloud layers with embedded towering cumuli within 180 miles of the line from 20°N 158°W to 12°N 170°W, though individual small cumuli also occurred throughout. These clouds generally moved toward the west southwest at 10 to 15 miles an hour, and rose to heights of 10000 to 15000 feet, though some of the towering cumuli approached 26000 feet.
Across the main Hawaiian islands, high to middle cloud layers ahead of the front obscured lower features mostly to completely over Kauai county, and partly over Oahu and the Big Island. Where it was visible, lower cloud cover consisted mostly of afternoon cumulus buildups with their layered debris clouds over higher terrain inland, though marine cumuli also moved ashore along slopes facing east. Areas with the greatest cloud cover included north parts of both mountain ranges on Oahu, the west Maui mountains, middle to upper slopes of Haleakala on Maui, and most middle to upper slopes of the Big Island. These lower clouds generally rose to heights of 10000 to 12000 feet. Radar data from near the islands showed areas of moderate to heavy rain well offshore to the north of Oahu, and scattered showers along lower south slopes of Haleakala on Maui, but isolated showers at most elsewhere.