Will the cyclone-in-making (94W) skirt the north Andhra Pradesh - south Odisha coasts? This seems plausible as along with the US-based NCEP, India's INCOIS (Indian National Centre For Ocean Information Services) has dropped a big clue today.
As per the latest INCOIS forecast, Cyclone Jawad will move very close to Pentakotta and Kalingapatnam at around 10-11 am on December 4 (Saturday). From that point, the cyclonic system will track a north-northeast direction.
With the change in direction, it seems the Cyclone will move parallel to Odisha coast up to the Paradip coast, and from there will take a further curve towards the northeast direction.
A look at the details of the forecast by India's ace ocean research organisation reveals that the cyclone tracking a northwest direction will move very close to Vishakapatnam and Srikakulam (Pentakotta to Baruva) at around 11 AM on Saturday (Dec 4). But the system instead of making landfall will track a north-northeast direction running parallel to the Andhra Pradesh coast.
Cyclone Jawad And Odisha
The NCEP-GFS and INCOIS data suggest that the Cyclone Jawad will run parallel to the Gopalpur coast around the evening hours on Dec 4, when the wind speed along the coast will attain a gale speed of over 70km/hr.
The gale speed wind will sweep along the coast of Odisha up to Paradip. Moreover, the significant wave heights along the coast will touch a high of over 10 feet between the night hours on December 4 and morning hours on Sunday (Dec 5).
The latest data of both models predict that the cyclonic system will then track a further northeast direction to make landfall in Bangladesh.
The JTWC Forecast
As per the Joint Typhoon Warning Centre (JTWC), the tropical disturbance 94W will intensify into a tropical cyclone as the wind speed will cross the 65 kmph threshold in the next 24 hours (by December 3 night hours). The analysis says the system is currently existing in a boundary layer of moderate (20knots) to low (5-10kts) vertical wind shear (VWS). The system will track continuously the northwest direction and enter into a zone of low VWS to intensify into Cyclone Jawad.
However, the analysis says, after intensifying into a tropical cyclone, further development of the system will be lackadaisical, though, it will chart a west-northwest track to reach near the coast of India.
Is High VWS Behind The Drift?
As per the NCEP data, since the vertical wind shear over Odisha and north Andhra Pradesh is predicted to remain between 25-35knots in the morning hour, and is slated to further rise to around 35-45 knots later, the wind shear seems not favourable for the system to track a northwest direction.
Moreover, the direction of upper-level winds (models show charting a northeast direction) seems to be a major reason behind the system taking a drift towards a favourable environment (to its northeast side). The system is slated to make landfall in Bangladesh, predicts NCEP-GFS.
A cyclone will intensify when it gets a wind shear of around or below 30 knots. But the model analysis predicts the wind shear over Odisha and north Andhra Pradesh will be hovering around 35 -45 knots. The direction of the upper-level winds is considered as an important determiner in forecasting the track of a tropical cyclone.
As the VWS is not high over the whole of north Bay of Bengal, the cyclonic system will not weaken. Instead, the system will track the supportive zone (the northeast Bay of Bengal).
Current Status Of 94W
As of now (at around 5:15 pm), the tropical disturbance is nearly 1066 km away from Vishakapatnam and nearly 1120 km from Gopalpur. The system in the last 24hours has charted a northwest direction. (see the main image). It has moved with a speed of around 45km/hr. The system's early clouds have been noticed on the Andhra Pradesh skyline.