The Aleutian low moved into the Bering Straight causing southerly flow over most of Alaska. The small surface low on the coast that was present on the 8th, had disappeared. Trajectories for the CV-580 flight area, 69.5 N and 138.3 W, show most air coming from Alaska to the south. The lowest level air came from the southwest, probably because of remnants of the coast low. Earlier in time, the air came from central Alaska at all levels, except for 6 and 9 km which came from western Alaska and the Bering Straight.
SHEBA ship trajectories show that the low level air came from the east - the Beaufort Sea and northern Canada, while from 1.5 km and above, the air came from the south.
Satellite images show a combination of broken cirrus over lower highly reflective stratus clouds. Open water was not visible on the satellite images in the area of the CV-580 flight.
