The newest western Pacific tropical storm could bring flooding rain to central Vietnam late in the week.
Monday's tropical depression over the South China Sea was upgraded and dubbed Tropical Storm Gaemi early Tuesday, local time, thus becoming one of two named tropical storms under way at the time.
Tropical Storm Maliksi was located at sea more than 1,000 miles south of Tokyo, Japan.
The center of Geami was more than 350 miles west-northwest of Manila, Philippines. Having winds of about 45 mph, Gaemi was drifting southeastward at about 5 mph.
Tuesday's tale of two storms: Tropical Storm Gaemi, between the Philippines and Vietnam, left; and Tropical Storm Maliksi, south of Japan, right. Taken 1330 UTC Tuesday, Oct. 2, 2012. (Japan Meteorological Agency -- JMA)
Weak steering winds will allow Gaemi to drift somewhat erratically over open water for at least another two to three days.
Eventually, easterly steering winds are forecast to begin over the region, thereby aiming Gaemi towards Vietnam.
Warm tropical surface water spread throughout the South China Sea will help to bring about strengthening of this tropical cyclone. It is too early to know whether Gaemi will ultimately become a typhoon before the time of landfall.
The month of October marks the height of the rainy season across the middle of Vietnam, and tropical storms making landfall from the South China Sea account for a significant fraction of region's rainfall between September and November.
Owing to the uplift of moist tropical cyclone winds overriding the mountain spine of eastern Indochina, flooding rainfall can -- and sometimes does -- reach 1 to 2 feet within 24 to 48 hours.
Latest numerical forecast model scenarios suggest the Gaemi can reach central Vietnam Friday or Saturday, bringing torrential rain and winds of tropical storm intensity.
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!