Flood in Taiya Inlet, Alaska

The atmospheric river moved across the the panhandle from the northeast gulf coast to the southern panhandle Monday through Tuesday morning. There were two bursts of heavy ran with totals near seal level ranging from three quarters of an inch to just over one inch. There was much more rainfall in the headwaters of the Taiya River with rain amounts from one and half to almost three inches at Chilkoot Pass. The initial bout of rain and high freezing levels produced a two and half foot rise on the Taiya River with the river going over minor flood stage of sixteen point five feet. The river remained just under moderate flood stage through the early morning hours of September 13th from the persistent rainfall. There was another burst of heavy rainfall and the river rose another half foot to go over the moderate flood stage of seventeen feet and crested at seventeen point twenty seven feet around 9 am. The rain tapered off through the late morning and the Taiya River began to slowly recede to be below minor flood stage by Tuesday afternoon. The National Park Service reported that there was significant flooding along the Chilkoot trail with waist deep water at the lower portions of the trail.

An atmospheric river that extended deep into the north Pacific moved over Southeast Alaska on September 12th and 13th. This plume of sub-topical moisture slowly moved through the area Monday afternoon through Tuesday morning with expected rainfall amounts over the northern Lynn Canal region of 1 to 3 inches. Also as the front spread east across the region it increased the freezing levels to be above the ridge tops of six thousand feet. This allowed for increased runoff from snow and ice melt in the Taiya River basin. The combination of the runoff from the snow/ice melt and the heavy rainfall produced moderate flooding along the Chilkoot trail by Tuesday morning.