METEOROW PART FIVE Yoke D- 1. Introduction On the days followingX-F@ Day, the weather situationwas characterized by a slow change from tha pNv~U% southe-terly flow of the equatorial air in the lower atmospheric layers to a more normal easterly h northeasterlyflow. The trade winds blew with moderate velocities of 15 to 18 knots but the anti-trades above 30,000 feet occasionallyreached speeds of ~ knots. There was also a high frequency of occurrence of west-northwestwinds in the anti-trades at levels between 20,000 d 30,000 feet, a not unusual condition for this season in the Marshalls. Although the weather conditions for the days precedi~ Yoke Daywe~ normal ad typical, the existence of mat-northwest winds in the mti-trades would cause a possible hazardous radioactivefall-out if firing were attempted tier these Prior to Yoke minus th~, wirricorr,titions. thre was eleven impossiblefiring daya because of wind conditions, these being April 19 through 29th. There had to be a definite change in the winds betoxw the Yoke Day detonation could take place. 2. Operations Yoke Day was scheduled for 30 April with H Hour at 0609M. On the 26th of April, the low, nmdium and high cloudiness increased rapidly ad frequent moderate showers covered the entire Eniwetok SECTION XII 44