Graphic warning for typhoon "Hagupit" by the Joint Typhoon Warning Center.
MANILA – The Hawaii-based Joint Typhoon Warning Center (JTWC) of the US Navy has categorized tropical cyclone ''Hagupit'' into a super typhoon.
The JTWC, in an update issued at 5 a.m. Thursday (Manila time), said Hagupit was maintaining a ''west-northwestward trajectory under the steering influence of the subtropical ridge."
This means that Hagupit was heading towards the Philippines as its upward movement was being blocked by the subtropical ridge, a large belt of high pressure in the northern hemisphere that is referred to as an anti-cyclone system.
The JTWC said as of 2 a.m. Thursday, Hagupit was packing 1-minute sustained winds of 240 kilometers per hour (130 knots) and gusts of 296 kph (160 knots).
The JTWC forecasts Hagupit to pack as much as 296 kph (160 knots) winds by December 7 (Sunday), 2 a.m., when it is nearer the Philippines.
In the JTWC model, Hagupit is seen heading slightly north and towards Luzon, avoiding the Yolanda-hit region of Visayas.
''The system will start to track slightly to the north at this timeframe. Expect favorable sea surface temperatures, along with continually favorable upper-level conditions to allow the system to further intensify,'' it said.
Philippine state weather bureau PAGASA, meanwhile, said Hagupit – which was locally named ''Ruby'' after it entered the Philippine area of responsibility today – was packing maximum sustained winds of 175 kph near the center and gusts of up to 210 kph.
PAGASA said Hagupit was spotted 942 kms east northeast of Hinatuan, Surigao del Sur as of 4 a.m. It said Hagupit slowed down, moving west northwest at 25 kph.
The Global Disaster Alert and Coordination System, meanwhile, has raised a red alert for Hagupit.
It said the typhoon ''can have a high humanitarian impact based on the maximum sustained wind speed and the affected population and their vulnerability."
The GDACS said the population that could be affected by Category 1 (120 kph) wind speeds or higher is 200,000.
Track of typhoon ''Hagupit'' (local name: Ruby) by the Global Disaster Alert and Coordination System
LANDFALL OR JAPAN?
The JTWC said both models provided by the Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS) and Global Forecast System (GFS) have been consistently showing Hagupit moving upward due to the weakening of the high pressure system.
The US weather bureau, however, said another model provided by the European Centre for Medium-Range Weather Forecasts (ECMF) shows Hagupit continuing its westward track into central Philippines, indicating that the weakening of the high pressure system may not be pronounced enough to make the weather system re-curve and move towards southern Japan.
Speaking to radio dzMM, PAGASA weather forecaster Samuel Duran said there is no definitive forecast yet on what course the typhoon will take. Nonetheless, he said local government units and residents in high-risk areas must still prepare for a possible evacuation.
Duran said even if Hagupit re-curves towards Japan, rains will still be felt in the eastern section of the country as early as Friday.
As of Wednesday evening, the National Disaster Risk Reduction and Management Council and PAGASA said more than 44 provinces have been declared as critical areas. These provinces are expected to experience heavy to intense rains and strong winds from 95 to 110 kph.
PAGASA MTSAT image as of 07:01 a.m., 4 December 2014.