HEADQUARTERS JOINT TASK FORCE SEVEN APO 437 San Francisco, California 12 June 1956 FLATHEAD BIKINI OBSERVED WEATHER FOR 12 JUNE 1956 AT DETONATION TIME 0626M Sea Level Pressure’ 1012.9 mb Free Air Surface Temperature Dew Point Temperature Relative Humidity 82.0°F 76 ,0°F 82.0% Surface Wind 050° at 10 knots Visibility 10 miles CLEUDS L/10 stratocumlus and cumlus; bases estimated at 2000 ft. 10/10 cirrostratus; bases estimated at 30,000 feet. WEATHER: © oS ‘No shower activity reported. Pressure . + BIKINI UPPER AIR SOUNDING (1119002) — :. Q&llibars) Lol 1000 947 850 770. 735 700 666 640 611 560 543 D2) 500 ~ 4,00 356 300 c Height (Feet) , . : 110 380 1,903 5,020 7,759 9,022 10,380 1,713 12,705 1,042 16,327 17,126 17,995 19, 250 24,840 275592 31,670 = = Temperature (°c) 27.8 26.8 22.2 17.2 W.2 10.8 08 .5 06.8 05.2 02.8 - 02,8 —~O4L.8 -04,.2 08.2 -19.2 25.2 32.3 ~~ Dew Point (°c) 24.5 23.5 19.5 11.8 01.5 —02,2 -02.4 02.5 -08.8 06.2 ~10.2 -20.5 -19.2 -11.8 -30.5 ~37 05 MN