TC 01A Comes, Goes

Jun 13, 2011; 12:51 PM ET

“ONE” NO MORE THAN MINIMAL TROPICAL STORM

The struggle for best forecast scenario related to the matter of cyclone (or no) in the Arabian Sea seems to have been won by none of the computer forecast models that I followed.

The right answer to the conundrum was that a minimal tropical cyclone (TC 01A, or “One”) wound up south of Kathiawar (Gujarat, India) late last week, then weakened to a tropical depression upon brushing the western shore of Kathiawar.

At this writing, the last of 01A is fading away well south of Karachi.

Path of the Cyclonic disturbance that became TC 01A, or “One” (Joint Typhoon Warning Center image).

According to the Joint Typhoon Warning Center (JTWC), highest sustained winds about TC One were 35 knots, or 65 km/hr.

Readers of this column may recall that at least one computer model (GFS) persisted for days in forecasting a major tropical cyclone over the northern Arabian Sea. It did not desist in this bent until TC One was a reality.

The NOGAPS and ECMWF showed nothing like the GFS scenario, but they did not show the Kathiawar storm. Even so, given that these two models did not show a potentially destructive cyclone, I believe it fair to say that they had the better forecasts.

LOOKING FORWARD…

Now that the cyclone conundrum is over, the focus for South Asia lies with the SW Monsoon. Its onset should take place progressively towards the north and the northwest over the coming days.

Over the coming days it will bear watching, whether or not a Monsoon low take shape over the NW Bay of Bengal.

I was not able to load the 2011 Monsoon onset map on the India Meteorology Department (IMD) site today, so I do not know where the latest line has been drawn. It had been, as I recall, drawn eastward from southernmost Gujarat to the northern Bay, thence northward through Bangladesh to the Himalaya.