On Peter %Ray minus one day and peter ~- DaY the weather Predictions were made with greater and greater detail ~d presented with ~cre-~ and significantly greater confidence. 2. Q_9erat ions Ruring the morning of peter ~~ ZItiS three (3), the outlook fore- cast for Peter GRay Day was prep~re~ A well defined pressure trough was located over the Japanese Zir O. The trough was predicted to move slowly eastward,migrating to ~out 300 miles to the west of Eniwetok by ‘W Hour. Although considerable-outs of middle clouds are usually associated with the approach of theee westerly troughs, no significant increase in cloudiness was forectist. The reason for this was that the pressure trough was expected to weaken considerably. However, with the anticipatedweakening of the preesure trough, a rather thick zone of light and variable winds was expected between the trade winds in the sface layers and the anti-trades at the higher altitudes. As a result, the weather forecast called for typical tropical weather of W tenths of scattered low cumulus clouds and 4 tenths of h5gh ncattered cirrus clouds and unfavorablewiads from the radiologicalpoint of view. At the briefing on 5 April at 1500H, the above w’eathertrends were explained,and the outlook weather forecast for Peter GRey Day vae presente~ The next formal weather briefing wae scheduled for Peter X-Eey minus one, However,during the imterim, the Commander, J!ET-70 and his staff were kept advised of the c~ent weather eituation and ~ ication in the forecast as originally given on Peter z&y modif- mimus 3 davs, 22 SECTIOX XII $unm-”