By PDC’s Senior Weather
Specialist Glenn James
The Pacific Disaster Center’s (PDC Global) Tuesday, July 18, 2023, Tropical Cyclone Activity Report…for the Pacific Ocean, the Indian Ocean, and adjacent Seas
Current Tropical Cyclones:
Tropical Cyclone 03E (Calvin)…is located about 175 miles southeast of Hilo, Hawaii
Tropical Cyclone 04W (Talim)…is located approximately 171 NM east-northeast Of Hanoi, Vietnam – Final Warning
Northeast Pacific Ocean:
South of Southwestern Mexico:
Disorganized showers and thunderstorms located a few hundred miles south-southwest of the coast of southwestern Mexico are associated with a tropical wave.
Some slow development of this system is possible during the next few days as it moves west-northwestward at 10 to 15 mph over the central portion of the eastern Pacific basin.
By this weekend, the system is forecast to move over cooler waters, and further development is not expected.
* Formation chance through 48 hours…low…10 percent
* Formation chance through 7 days…low…20 percent
Central Pacific Ocean:
Tropical Cyclone 03E (Calvin)
TROPICAL STORM CALVIN APPROACHING THE BIG ISLAND…IMPACTS IN HAWAII COUNTY STARTING THIS EVENING
According to the CPHC advisory number 30
Calvin is moving toward the west near 21 mph (33 km/h), and this general motion is expected to continue over the next few days. On the forecast track, tropical storm conditions will likely begin spreading over Hawaii County starting this evening.
Maximum sustained winds are near 60 mph (95 km/h) with higher gusts. Calvin is expected to remain a tropical storm over the next 36 hours, and then will weaken quickly afterward.
Tropical-storm-force winds extend outward up to 140 miles (220 km) from the center.
HAZARDS AFFECTING LAND
WIND: Tropical storm conditions are expected within the warning area starting this evening. Preparations for tropical storm force wind impacts should already be completed for persons in Hawaii County.
RAINFALL: Storm total rainfall amounts through Thursday are forecast to be 4-8 inches, with maximum amounts of 10 inches possible, mainly along the windward slopes and southeast flank of the Big Island of Hawaii. Storm total rainfall amounts of 3-6 inches are expected on the windward areas of Maui, and 2-4 inches elsewhere in the state. This rainfall could lead to localized flash flooding and mudslides.
Swells generated by Calvin are expected to begin spreading across the main Hawaiian Islands tonight. This will lead to a rapid increase in surf along east facing shores, with high surf continuing into Wednesday. This elevated surf will likely cause life-threatening conditions along exposed shorelines.
Western Pacific, Indian Ocean and adjacent Seas:
Tropical Cyclone 04W (Talim) – Final Warning
According to the JTWC warning number 15…sustained winds are 60 knots with gusts to 75 knots
TS 04W has gradually deteriorated over the past six hours and made landfall near the eastern base of the Leizhou Peninsula.
Animated satellite imagery depicts slow decay of the outermost convective banding and obscuration of the low level circulation center (llcc). Animated weather radar shows evidence of a ragged eye persisting despite the greater northern semicircle propagating westward over land. An infrared image positioned deep convection in the southern periphery and relatively shallowed convection poleward of the llcc due to the influence of land induced friction.
TS 04W is forecast to track west- northwestward through 36 hours under the steering influence of deep-layer easterly flow to the north. Land interaction and dry air entrainment along the northern periphery will gradually cause 04W to dissipate.
>>> There’s an area of disturbed weather being referred to as Invest 98W…which is located approximately 85 NM north of Palau.
Animated multi-spectral satellite imagery reveals a broad low level circulation (llc) partially obscured by deep broad convection along the southern semi-circle.
Environmental analysis reveals marginally favorable conditions characterized by moderate equatorward outflow aloft offset by low to moderate (15-20 knot) vertical wind shear. Sea surface temperatures remain warm.
Global models are in agreement that Invest 98W will steadily develop as it remains quasi-stationary before propagating northward around 48 hours.
Maximum sustained surface winds are estimated at 15 to 20 knots.
The potential for the development of a significant tropical cyclone within the next 24 hours remains medium.