Typhoon Sarah, 1956, the first of the season, was unusual in several respects. First, Sarah formed in a tropical depression that first became a closed circulation less than a hundred miles from the equator. Second, Sarah showed a marked diurnal variation in intensity after reaching a maximum of intensity on the second day as a typhoon. Third, besides the diurnal variation there were two periods of intensification and weakening. Fourth, the cyclone retrograded to the east-southeast several hundred miles parallel to its previous track. The diurnal variation of Typhoon Sarah appears to have its origin in the arrival of short intense lines of convergence at the eye. The arrival of these lines of convergence at the eye furnished the energy that gave the typhoon a pulsating characteristic.

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The surface wind-speed reports in tropical cyclones given by aircraft-reconnaissance observers are based almost exclusively on state-of-sea observations. The reliability of wind estimates prepared in this manner is considered along with some of the practical difficulties involved in making observations from reconnaissance aircraft.

Blowing dust (Fuhjin) and to a lesser degree dust devils occur with a fairly high degree of regularity each year in the Kanto Plains of Japan during late winter and early spring. The occurrence of blowing dust is in general a post cold front problem, during periods of little or no precipitation.