A low pressure, BB-1,  develops in the Southern Bay, SE off Sri Lanka around the 6th of May. Strengthened by various factors, the system will deepen into a depression by the 8th and a deep depression by the 9th/10th.
Due to "high" resistance initially,BB-1 will not move beyond the 10N line till the 10th, and may just come upto East off Sri Lanka.  
Sri Lanka, east coast in particular, gets very heavy rains from the 7th of May...
 
Very soon, thereafter, indications are there of a rapid North wards movement due to favourable conditions, and possibly deepen more on its track.
 
Vagaries will monitor the strength of BB-1, now a Deep Depression and its track, as it moves past Chennai after the 11th of May.

Vagaries will announce if necessary the "Cyclone alert" once the strength and track of BB-1 is defined.
At the same date, another strong system would have formed S/SW off BB-1, but below the Equator at 8S. Its going to complicate matters for the SWM...there will be hardly any clouding for the Andaman Seas..?? But our Andaman date could remain intact..??

See more on vagaries.

Today as well, the trough from S.Bihar is seen upto S.Tamilnadu, passing thru Chatisgarh, N.Andhra and S.Karnataka... http://ow.ly/i/21US8 

And this trough from S.Bihar to S.Tamilnadu is expected to persist for another 2 days ... http://ow.ly/i/21V41 

S,S-W Bay is expected to pop a circulation on 4/5-May ... http://ow.ly/i/21V87 

Weak circulation over North N-E states persists ... http://ow.ly/i/21VHr 

6pm, T.showers seen over N-W,S Tamilnadu, S,S-central Karnataka, central Andhra, Coastal,N-E Odisha, North N-E states http://ow.ly/i/21SLd 

#HOT at 1:40pm, Nagpur airport is reporting 46 C, Ahmedabad, Hyderabad, Varanasi = 41 C, Patna = 40 C, Jaipur = 38 C, Amristar, Delhi = 37 C

At 1:10pm, Trivandrum airport has reported some Rain ... with temperature around 31 C.

#Chennai - 1:40pm, temperature = 36 C and feels like 44.7 C. Humidity around 53 % and a mild Sea breeze has set in from S-E.

Yesterday, highest maximum  temperature of   45.6°C  has been recorded at  Nagpur (Maharashtra)

1:30pm, Heavy rain seen over Southern N-E states and mild rain seen over S.Tamilnadu and S. Kerala ... http://ow.ly/i/21NrE 

Today morning's upper level circulation over S-W Kashmir and Punjab has moved away to East ... http://ow.ly/i/21qIM 

Next W.D circulation is expected to reach N-W Pakistan on 4-May ... 

 W.D rain is expected to start again over Kashmir, Himachal from 4-May ... http://ow.ly/i/21qQU 

T.Showers to persist for W-Ghats of Kerala during next 3 days ... http://ow.ly/i/21p1L 

Some T.showers are also expected over W,N-W,central Tamilnadu and into S,S-W Karnataka as well during next 3 days.. http://ow.ly/i/21p5t 

Isolated T.showers also possible for N-E Andhra and into S.Odisha till 5-May ... http://ow.ly/i/21pak 

After 4-May, the upcoming circulation over Bay may disrupt the present #HOT weather over South peninsula .!

For #Chennai, due to upcoming circulation over Bay, HEAVY rain expected on 7,8,9,10-May according to latest COLA model ... may become TRUE !

Heavy scattered rain to continue over N,central N-E states ... http://ow.ly/i/21pQm 

From 4-May, some showers may push into N,central Bengal ... http://ow.ly/i/21pW5 

Today, a trough is seen extending S-W from Bihar, N.Chatisgarh upto S-W Karnataka ... http://ow.ly/i/21jvH 

Tomorrow, This trough may become even more North-South from Bihar to S.Tamilnadu ... and persist till 5-May .. http://ow.ly/i/21jy2 

S,S-W Bay is expected to pop a low level circulation on 5-May... 

COLA model suggests : The upcoming circulation over S.Bay may deepen and cross into S-E,central Tamilnadu coast ... 

But the IMD model suggests that it may attain Cyclonic strength over S.Bay itself on 8-May ... 

5pm, T.showers seen over N.Karnataka, central W-Ghats of Kerala, S.Kerala and over S.Tamilnadu ... http://ow.ly/i/21jmC 

"Reason behind more Arabian sea Cyclones" - El Nino Modoki

It is a well known climatological fact that during pre-monsoon and post-monsoon seasons in the North Indian Ocean, more cyclones form in the Bay of Bengal compared with the Arabian Sea. Scientists have now discovered why in some years more cyclones form in the Arabian Sea than usual. This is due to a newly discovered Phenomenon (2007) El Nino Modoki — which causes warm moist conditions in the Central Pacific and dry cold conditions in Eastern and western pacific. A more familiar phenomenon, El Nino, was found to suppress cyclone formation in the Arabian Sea.

The findings are results of a study undertaken by a team led by Dr. M.R. Ramesh Kumar, Senior Scientist, National Institute of Oceanography, Goa. The study has been published in the Natural Hazards journal.

The reason why El Nino Modoki brings only fewer number of cyclones in the Bay of Bengal is because one of the two descending limbs of the Walker Cell is over the western Pacific and Bay of Bengal. The descending limb causes dry conditions not conducive for cyclone formation. The ascending limb of the Walker Cell, on the other hand, brings rain. Also, an El Nino Modoki creates stronger divergence over the western Pacific and Bay of Bengal compared to El Nino. Divergence (opposite of convergence) means surface winds move away from each other and result in low relative vorticity (rotational flow of winds). These conditions are not conducive for cyclones. This explains why Bay of Bengal region (close to western Pacific) has fewer cyclones during an El Nino Modoki.

On the other hand, there is large convergence over the Arabian Sea during an El Nino Modoki explaining the large number of cyclones in that region. A statistical analysis of the El Nino and El Nino Modoki years between 1979-2004 was conducted. It was found that there were four El Nino years and seven El Nino Modoki years during this period.

The number of cyclones per year show significant differences indicating that El Nino Modoki years are conducive for cyclone formation over Arabian Sea while El Nino is conducive for cyclones over the Bay of Bengal.

Only post-monsoon and pre-monsoon periods were chosen for the study. “Cyclones usually do not form during monsoon season,” Dr. Ramesh Kumar says in an email to this Correspondent. There are a few reasons for this.

“Atmospheric parameters — low-level relative vorticity, mid-tropospheric relative humidity, vertical wind shear — are not at values conducive for cyclone formation during monsoon,” Dr. Ramesh Kumar says. Second, during monsoon there is strong zonal (latitudinal) wind in the form of a jet at lower levels and this is not conducive for cyclone formation as the vertical shear between lower and upper troposphere will not be minimum.

Finally, the sea surface temperatures are too low for cyclogenesis.

Taken from http://www.thehindu.com

1-May-2013, highest maximum temperature of 45.8°C was recorded at Chandrapur (Maharashtra)

2:10pm, Nagpur airport is reporting 47 C (and feels like 44.4 C)

#HOT at 2pm, Varanasi = 44C, Ahmedabad = 41C, Kolkata, Jaipur = 37C, Bangalore, #Delhi = 36C.

#Chennai = 2pm, temperature around 36 C (feels like 42C)  with humidity around 47% and mild sea breeze from S-E.
2pm, MOST of India is clear and #HOT, except for some rain over N-E states and cloudy over central,N-W Tamilnadu http://ow.ly/i/21ggx 

In next 12hrs, T.showers possible over S,S-W Tamilnadu, scattered over Kerala, S,S-W, central,N.Karnataka ..