The W.D. in the northern region has been restricted a bit to the North, but not enough, as it has pushed off the heat wave. As the temperature map from IMD shows, the heat wave is now restricted to a small area in the east, and much of the subcontinent is normal, or even below normal.
The temperatures are fairly "moderate'' and the highest in the subcontinent today was Machhillipatnam(east India) at 45° and then Nawabshah and Jacobabad at 44°.
Now this has weakened the south westerly flow from the Arabian Sea temporarily, due to poor temperature gradiant, and as this streamline from IMD shows, the south westerly flow has somewhat bifurcated into two parts, that is weakened, from the western Arabian Sea area.
The cooling of the sea waters off the Somali coast has also slowed down to some extent, and as a result, the pushing of the mass of monsoon clouds towards the Indian shores has halted, as of today, near the 60°E line as seen in this satellite image from NCEP.Image also shows the weak clouding of the W.D.in the North.
But I think this may have only delayed the monsoon date by a few days (from 24th. May). As the W.D. weakens, the South West winds should regain strenght, and bring back the monsoon cloud mass towards Kerala, maybe a few days later towards the end of May. The COLA site at http://wxmaps.org/pix/prec6.html indicates a burst of monsoon over Kerala between 28th. May and 3rd. June.
Due to the reversal of the sea breeze,the temperatures in Chennai have been high at 42°, since the last few days.