Cyclone from S-W direction?

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The deep depression over east-central Arabian Sea further moved north-northwestwards and has intensified into a cyclonic storm (also known as ASHOBAA).  It is about 590 km west-southwest of Mumbai. It is further expected to move north-northwestwards to intensify into a severe cyclonic storm during next 36 hours.

Forecast track and intensity of the system are given in the table below:

Date/Time(IST) Position

(Latitude 0N/ longitude 0E)

Maximum sustained surface

wind speed (kmph)

Category of cyclonic

disturbance

08.06.2015/0830 17.9/67.2 60-70 gusting to 80 Cyclonic Storm
08.06.2015/1130 18.3/66.9 60-70 gusting to 80 Cyclonic Storm
08.06.2015/1730 19.0/66.5 60-70 gusting to 80 Cyclonic Storm
08.06.2015/2330 20.0/66.0 70-80 gusting to 90 Cyclonic Storm
09.06.2015/0530 21.0/65.3 80-90 gusting to 105 Cyclonic Storm
09.06.2015/1730 21.7/64.5 90-100 gusting to 120 Severe Cyclonic Storm
10.06.2015/0530 22.5/63.7 90-100 gusting to 120 Severe Cyclonic Storm
10.06.2015/1730 23.0/63.0 90-100 gusting to 120 Severe Cyclonic Storm
11.06.2015/0530 23.5/62.4 80-90 gusting to 105 Cyclonic Storm
11.06.2015/1730 23.9/61.8 60-70 gusting to 80 Cyclonic Storm
12.06.2015/0530 24.3/61.0 50-60 gusting to 70 Deep Depression
12.06.2015/1730 24.5/60.5 40-50 gusting to 60 Depression

 

Under the influence of this system, rainfall would occur at most places with isolated heavy falls over coastal Karnataka, Konkan & Goa and south Gujarat during the next 24 hours.

Strong winds speed reaching 70-80 km/h gusting to 90 km/h would prevail along and off Karnataka, Goa and Maharashtra coasts during next 24 h and 90-100 km/h gusting to 120 km/h during subsequent 24 h. Sea condition would be very rough to high along and off Karnataka, Goa and Maharashtra coasts during the next 48 h.

Fishermen along and off Karnataka, Goa, Maharashtra and Gujarat coasts are advised not to venture into the sea during next 48 hours. Fishermen out at open sea are advised to return to the coast.

Monsoon forecast

Since April 2015, weak El Nino conditions are established over equatorial Pacific Ocean. Atmospheric conditions like weakened trade winds, negative Southern Oscillation Index (SOI) values etc generally associated with El Nino conditions are also observed. The latest forecast from IMD-IITM coupled model indicates El Nino conditions are likely to
strengthen further and reach to moderate strength during the monsoon season. There is about 90% probability of El Nino conditions to continue during the southwest monsoon season. Over Indian Ocean, currently, slight basin wide warming along with neutral Indian Ocean Dipole (IOD) conditions is prevailing. The latest forecast from ESSO-IMD-IITM coupled model indicates about 50% probability of neutral IOD conditions to continue during the monsoon season.

The experimental forecast based on the ESSO-IMD-IITM coupled dynamical model suggest that the monsoon rainfall during the 2015 monsoon season (June to September) averaged over the country as a whole is likely to be 86%±5% of long period model average (LPMA). The experimental five category probability forecasts for the 2015 monsoon season rainfall over the country as a whole using the experimental dynamical prediction system are 61% (deficient), 24% (below normal), 13% (normal), 2% (above normal) and 0% (excess).

Quantitatively, the season rainfall for the country as a whole is likely to be 88% of the long period average (LPA) with a model error of ±4%. The LPA rainfall over the country as a whole for the period 1951-2000 is 89 cm.

The 5 category probability forecasts for the Season (June to September) rainfall over the country as a whole is given below:

Met monsoon forecast

The season rainfall is likely to be 85% of LPA over North-West India, 90% of LPA over Central India, 92% of LPA over South Peninsula, and 90% of LPA over North-East India all with a model error of ± 8 %.

The rainfall over the country as a whole is likely to be 92% of its LPA during July and 90% of LPA during August both with a model error of ± 9%.