Page:NTSB Southern Airways Flight 932 report.pdf/11

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1800-2300, 300 feet scattered, ceiling 500 feet broken, 1,00 feet overcast, 1-1/2 miles, light rain, fog, scattered clouds variable to broken.

The official surface weather observations for Huntington bracketing the time of the accident were as follows:

1855, 300 feet scattered, measured 500 feet variable broken, 1,100 feet overcast, 5 miles, light rain, fog, smoke, temperature 49°, dewpoint 47°, wind 360°, 4 knot, 29-67, ceiling ragged and variable 400 to 600 feet.
1945, 300 feet scattered, estimated 500 feet broken, 1,000 feet overcast, 5 miles, light rain, fog, smoke, temperature 49°, dewpoint 47°, wind 210°, 4 knots, 29.67, ceiling ragged, aircraft accident.
1956, record special, partial obscuration, estimated 500 overcast, 3/4-mile very light rain, fog, smoke, temperature 49°, dewpoint 47°, wind 290°, 5 knots, 29.67, fog obscuring 5/10 of the sky, ceiling ragged, intermittent very light rain.

The National Weather Service specialist who made the observations testified that "... I thought the visibility was remarkably good when I took my local (the 1945 observation), but about 10 or 15 minutes after that the fog formed very rapidly, and that's when the visibility came down... it was right over the field. It just seemed like it formed very rapidly and it just actually sank right over the whole field."

The Huntington 1900 radiosonde ascent showed saturated or virtually saturated conditions with stable air from about 2,000 to 5,000 feet and otherwise a moist adiabatic lapse rate. The freezing level was at 7,500 feet. The upper wind observation associated with his ascent was in part as follows.

Height
(feet m.s.l.)
Direction
(°true)
Velocity
knots
Surface 360 7
2,000 075 12
3,000 130 18

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