Sanjeev Kumar Patro

Bhubaneswar: Its seems the temple town of Puri is all set to bear the fury of Extremely Very Severe Cyclonic Storm (EVCS) Fani. The likely place of landfall has now been forecast as Puri, one of the char dhams in India, at early morning of 5:30 AM.

But post making landfall, as the system will drift along the north-east direction, 'Fani' will move along the coastal region of Jagatsinghpur, Kendrapara and Balasore before entering West Bengal.

The latest model of Indian National Centre of Ocean Information Services (INCOIS) clearly hints at 'Fani' making landfall in south of Puri at around 5:30 hrs of Friday (May 3).

However, the latest Tropical Cyclone (TC) analysis by Joint Typhoon Warning Center's (JTWC) forecasts 'Fani' to skirt the east coast of India and make land fall at south west of Kolkata at TAU 84, which means at 12- 1PM noon on Friday (May 3). Earlier today, JTWC has made a forecast that 'Fani' world make landfall in the northeast coast of India, which means from Paradip to Sagar Island (West Bengal) in the night of May 3.

Why 'Fani' steers its path towards West Bengal than Odisha? As per JTWC's TC analysis the conditions are very much favourable for taking a re-curve towards northeast ward, instead of moving north. Had it been moved north wards, JTWC observed Odisha would be on its hit track. Since a new STR is developing over northern Thailand, Fani will re-curve northeast ward.  For which, it will veer towards West Bengal.

What is Sub Tropical Ridge(STR)? It's an airflow pattern that have high atmospheric pressure and aids cloud formation. Since tropical cyclones are low pressure systems, it track towards high pressure zones. And the STRs during summer move towards poles and turn eastward. And 'Fani' is simply following the STR curvature.

As per the JTWC TC analysis, 'Fani' has upgraded the TC with an intensity from T 4.5 -5 to T4.7 - 5. For which, the wind speed accompanying the cyclonic system will now touch 153 - 167 KM/hr from 147 - 167 Km/hr in its earlier forecast. But the gusting speed may touch around 180Km/hr.

However, IMD has predicted the wind speed at around 180Km/hr with gusting wind speed of around 205Km/hr. It further added that Fani will make landfall to the south of Puri in afternoon hours of May 3.

The JTWC analysis shows 'Fani' moving at speed of around 21Km/hr in the Bay of Bengal (BoB). The slower speed hints at 'Fani' gaining more steam.

However, If INCOIS-IMD joint prediction prove true then Odisha's twelve districts are in the cone of EVCS Fani effect, the districts of Puri, Khurda, Jagatsinghpur, Cuttack, Kendrapara and Balasore seem all set to bear the rain and gale fury of 'Fani'. As the system has very tightly wrapped spiral rain bands, it is expected to bring very heavy rainfall and high gale speeding up to around 180 Km/hr in the landfall place and its subsequent tracking zone. IMD warned that isolated places in Odisha's coastal districts would witness rainfall in excess of over 20 cm or 200mm. North odisha districts to witness very heavy rainfall on Saturday (May 4).

IMD has also cautioned Odisha government to take necessary precaution to prevent Fani induced damages in districts of Ganjam, Gajapati, Khurda, Puri and Jagasinghpur.

But If JTWC's model prove correct than Odisha would see only good rainfall and moderate wind speed of around 40 -50 Km/hr on May 3 and 4.

But storm surge warnings will be there, in any case, for the districts of Puri, Jagatsinghpur, Khurda and Ganjam.

But both INCOIS and JTWC analyses show 'Fani' showing a deepened convective structure that is becoming more symmetrical, which implies that the cyclonic system has developed into an intense cyclonic system.  It is well known that during intensification of a cyclonic system, the inner core convective structure was more asymmetric (unorganised).

Moreover, the contraction of the eye of 'Fani' that is wrapped around with compact rain bands indicate the severe intensification process of 'Fani'. It need reminding that during rapid intensification, the microwave 'eye' of cyclonic storm contracts.

The BoB is still supporting 'Fani' as the TC analysis shows sea surface temperature (SST) at around 31-33 degree Celsius, low vertical wind shear at around 22.5Km/hr and strong coriolis effect - means outward flow of air towards equator and poles.