twenty knots in the regions between Eniwetok and Wake. Small amounts of cumulus cloud, usually about 5/10 coverage, are found in this cur. rent. They do not extend much above 8,000 feet in the north or 12,000 feet in the south. in sometimes falls from some of these clouds, particularly in the south, but it is usually in the form of light showers. No extensive middle or upper cloud decks are found, Although the lower winds are northeasterly and quite fresh, as one ascends in the atmosphere over the northern Marshalls one finds that the-winds turn more westerly with increasing elevation until at about 20,000 feet they lie between northwest and southwest. The westerlies then extend upwards to the tropopause, increasing in speed to about thirty-five knots at 45,000 feet; above the tropopause the winds again become easterly. If the tropospheric upper winds in the region should be mainly southwesterly, rain from the trade cumulus is likely and the amount of cloud may increase from time to time to as much as 8/10. On the other hand, if these up~ per winds are chiefly northwesterly in direction, cumulus clouds may decrease to as little as 2/10 or 3/10 and showers are less likely. The variation between northwest and southwest is controlled by an upper level pressure trough which tends to be located just west of Eniwetok during trade weather. The difficulties in fore~ casting variations in trade weather, then, are associated with small movements of the trough line to and from across the northern Mar~ shalls. 166