Heavy Rain in Alaska, August 11 to 13, 1999

Heavy rains preceded a vigorous subtropical low across Kodiak Island Wednesday and Thursday. This low was a very interesting one, meteorologically, in that it formed in the northern part of the central Pacific and actually developed an eye for about 12 hours Tuesday. Actually, as the low moved over cooler water, it began to weaken, transferring much of the moisture it carried to a system further northeast. While the ASOS site at the Kodiak airport recorded less than .10 inch of rain during this time period, due to a 'rain shadow' effect from brisk southwesterly winds aloft, a gauge at Booth Lake in the southwest part of the island recorded close to 2 inches in less than 24 hours.Heavy rains also moved into Southcentral Alaska early Thursday...continuing for close to 24 hours. Several reports of rainfall in excess of 2 inches (much of which occurred in a 12 - 18 hour period) were recorded in the Susitna Basin. Portions of the central and western Copper River Basin were also affected by heavy rains.