The plum rains are known as "meiyu" in China, the "baiyu" or "tsuyu" in Japan, and the "jangma" in the Koreas. The heart of the plum rain season stretches from early June to mid-July, with a tendency to shift south to north across the affected area.
In the wake of the mid-June cloudbursts, most of Pakistan to northwestern India last week saw a return to dry, hot weather typical of the weeks leading up to the Monsoon onset. It was as if the Monsoon withdrew to its "normal" position for the latter half of June.
The 38.5 degree C (101 degrees F) reading Tuesday in Ajaccio, Corsica, may have been tops in Europe.
Monsoon Onset was June 13th, 2013, in Delhi, almost two weeks earlier than average. The June 15th onset at Karachi and Islamabad was more like three week ahead of schedule.
In Pakistan, hit-or-miss downpours missed the Sindh capital, Karachi. One did hit Pad Idan, where it left 60 mm of rain Wednesday. This was more than 20 times greater than the normal June rainfall.
It is still possible that this scenario is over wrought as to the intensity and spread of rain in Pakistan and northwestern India. However, it is the hunch of the present forecaster that some very unusual weather is going to unfold in the Subcontinent during the next week!
North of the expected Monsoon low, moist, rain-cooled air should flow northward to the Himalayas, even westward into the Indus Valley of Pakistan, the result being scattered downpours along with a break in the pre-Monsoon heat next week.
On Wednesday, June 5, 2013, the South West Monsoon was set to leap northward on the Indian Subcontinent by the middle of the month.
According to preliminary data not including the last three days of May, it was the coldest spring since 1962 and the fifth coldest since 1910, when comprehensive record keeping began in the U.K.
In justifying the declaration of Monsoon onset, the IMD cited widespread rainfall, some heavy, throughout Kerala; deep, vigorous southwesterly winds over the southern Arabian Sea; and the widespread high cloudiness as measured by satellite.