By PDC’s Senior Weather
Specialist Glenn James
The Pacific Disaster Center’s (PDC Global) Tuesday, October 17, 2023, Tropical Cyclone Activity Report…for the Pacific Ocean, the Indian Ocean, and adjacent Seas
Current Tropical Cyclones:
Tropical Cyclone Norma…is located approximately 650 miles south-southeast of Cabo San Lucas, Mexico
Tropical Cyclone 16W…is located approximately 86 NM east-northeast of Da Nang, Vietnam
Northeast Pacific Ocean:
Tropical Cyclone Norma…
According to the NHC advisory number 2
Norma is moving toward the northwest near 8 mph (13 km/h), and a northwestward to north-northwestward motion at a slightly slower forward speed is expected during the next several days.
Maximum sustained winds have increased to near 50 mph (85 km/h) with higher gusts. Steady to rapid strengthening is forecast, and Norma is likely to become a hurricane on Wednesday.
Tropical-storm-force winds extend outward up to 140 miles (220 km) from the center.
>>> South of Guatemala and Southern Mexico…
An area of low pressure is forecast to form south of the coasts of Guatemala and eastern Mexico in a couple of days.
Gradual development of this system is expected, and a tropical depression is likely to form late this week or over the weekend while the system meanders over the far eastern portion of the basin.
* Formation chance through 48 hours…low…20 percent
* Formation chance through 7 days…high…70 percent
Central North Pacific:
There are no tropical cyclones, nor any areas of disturbed weather under investigation by the CPHC at the time of this writing.
Western Pacific, Indian Ocean and adjacent Seas:
Tropical Cyclone 16W
According to the JTWC warning number 3…
The system had sustained winds of 30 knots, with gusts to 40 knots
Animated enhanced infrared satellite imagery shows a ragged developing system in the South China Sea with flaring convection near the central dense overcast (cdo) and a fragmented formative band loosely wrapping toward the cdo that is obscuring the low level circulation (llc).
Analysis indicates a marginally favorable environment, with low vertical wind shear and warm sea surface temperatures tempered by weak radial outflow and proximity to land.
Under the steering influence of the ridge to the east-northeast, TD 16W will continue to track northwestward towards the Gulf of Tonkin. After 48 hours, a secondary, shallow ridge approaching from the west will compete for steering and force the cyclone in a quasi-stationary mode before slowly driving it southward.
The marginally favorable environment will fuel a modest intensification to a peak 0f 40 knots by 48 hours. Afterward, land interference from northern Vietnam to the west and Hainan Island to the east, plus sea surface temperatures cooling, due to cyclonic upwelling due to the nearly stationary storm motion, will gradually weaken the system down to 25 knots by 120 hours.