8:30 a.m. Wednesday, Aug. 17, Japan time: Tropical Storm Chanthu's forward speed slowed for a bit as it neared the Tokyo-Kanto Plain area overnight Tuesday into Wednesday -- almost as if it wanted to get a nice nighttime view of the world's most exciting city.
But it's now accelerating north-northeast, skimming Japan's east coast, planning to pay a brief visit east of Misawa Air Base on Wednesday afternoon before heading in Hokkaido's general direction and its eventual demise.
Chanthu continues packing 40-mph sustained winds and 52-mph gusts at center. The rain in the Tokyo area has slowed in some spots and stopped altogether in others. Should be cooler the next day or so. PST signs off on Chanthu unless something changes.
6:30 p.m. Tuesday, Aug. 16, Japan time: Fleet Activities Yokosuka entered Tropical Cyclone Condition of Readiness Storm Watch at 2 p.m. Tuesday due to the approach of Tropical Storm Chanthu. U.S. Army Garrison Japan at Camp Zama has a two-hour delay to the start of Wednesday's duty day. Those according to the bases' respective official Facebook pages.
Chanthu remains on course to sideswipe eastern Japan, 80 miles east of Yokosuka at 11 p.m. Tuesday and 26 miles east of Misawa Air Base at 2 p.m. Wednesday, packing sustained 40-mph winds and 52-mph gusts at center.
CFAY's Facebook page stated that Yokosuka and its satellite bases can expect between 2 to 4 inches of rain and wind gusts up to 50 mph. Expect all clear to be announced at Yokosuka by noon Wednesday.
Noon Tuesday, Aug. 16, Japan time: Picking up forward speed. Too far north. Too close to land. Cooler sea-surface temperatures. Dry air engulfing it. All of that spells demise in the next day or so for Tropical Storm Chanthu, moving north-northwest at 16 mph and still on course to graze east Japan early Wednesday morning.
Peak 46-mph sustained winds and 58-mph gusts at center as Chanthu passes 74 miles east of Yokosuka Naval Base at about 2 a.m. Wednesday. diminishing to 40-mph sustained and 52-mph gusts as it passes 33 miles east of Misawa Air Base at around 6 p.m. Wednesday.
All Kanto Plain bases remain in Tropical Cyclone Condition of Readiness All-Clear at the moment. Check with officials channels for possible delays to the start of the nominal work day.
6 p.m. Monday, Aug. 15, Japan time: Tropical Storm Chanthu is again forecast to pass the Tokyo-Kanto area and Misawa Air Base sooner than previously forecast: 100 miles east of Yokosuka Naval Base at 4 a.m. Wednesday and 72 miles east of Misawa at 7 p.m. Wednesday. Joint Typhoon Warning Center has also dialed back peak intensity to 58-mph sustained winds and 75-mph gusts for about 12 hours Tuesday evening into Wednesday morning.
Noon Monday, Aug. 15, Japan time: Little change to Tropical Storm Chanthu's long-range outlook. Slight increase in peak intensity; Chanthu is expected to briefly peak at 63-mph sustained winds and 81-mph gusts at mid-morning Tuesday, then decrease as it pushes north.
Chanthu remains forecast to brush Japan's east coast, about 100 miles east of Yokosuka Naval Base at mid-morning Wednesday, still packing 52-mph sustained winds and 63-mph gusts as it rumbles past; then 52 miles east of Misawa Air Base at 10 p.m. Wednesday, with 46-mph sustained winds and 58-mph gusts at center. Earlier than previously anticipated. And it could be sooner still.
Midnight Sunday, Aug. 14, Japan time: Tropical Storm Chanthu’s forward speed has increased to 18 mph and is now forecast to peak at 58-mph sustained winds and 75-mph gusts at mid-morning Tuesday, lower than previous projections, according to the Joint Typhoon Warning Center.
Chanthu is forecast to pass a wee bit further east of Japan’s east coast as well, and sooner: 106 miles east of Yokosuka Naval Base at 2 p.m. Thursday, instead of mid-evening; then 44 miles east of Misawa Air Base at 10 a.m. Friday, again instead of mid-evening, as previously forecast.
6:15 p.m. Sunday, Aug. 14, Japan time: Tropical Storm Chantu continues Sunday evening on a forecast track to sideswipe the Tokyo-Kanto Plain area Thursday evening, followed by a near-direct hit on Misawa Air Base the following evening, according to the Joint Typhoon Warning Center.
At 3 p.m., Chantu was 214 miles southeast of Iwo Jima, tracking north-northeast at 18 mph, picking up forward speed and still packing 40-mph sustained winds and 52-mph gusts. Chantu is still not forecast to reach typhoon strength, peaking at 69-mph sustained winds and 86-mph gusts at mid-afternoon Thursday.
If it remains on its JTWC forecast track, expect Chantu to roll 82 miles east of Yokosuka Naval Base at about 10 p.m. Thursday, still packing sustained 63-mph winds and 81-mph gusts at center. Winds at Yokosuka should not be quite that strong, but expect a gusty, rainy evening nonetheless.
Chantu should then make its way inland and make a near-direct hit on Misawa at 10 p.m. Friday, still with 52-mph sustained winds and 63-mph gusts at center. All Kanto Plain bases and Misawa currently remain in Tropical Cyclone Condition of Readiness All-Clear; expect that to change sometime Monday for the Kanto Plain.
There's still some disagreement among model guidance; that should improve as the days go by. PST remains on watch.
Noon Sunday, Aug. 14, Japan time: Chantu has been upgraded to a tropical storm by the Joint Typhoon Warning Center, and remains on a zig-zag course that's projected to take it just east of the Kanto Plain Thursday morning, then Misawa Air Base overnight.
At 9 a.m., Chanthu was about 300 miles south-southeast of Iwo Jima and had picked up forward speed, heading northeast at about 14 mph, packing sustained 40-mph winds and 52-mph gusts at center.
Chanthu is forecast to peak at 69-mph sustained winds and 86-mph gusts at mid-morning Wednesday, just below typhoon strength, as it zeroes in on Japan's northeast coast.
Chanthu should pass about 74 miles east of Yokosuka Naval Base early Thursday morning, still packing significant tropical storm-force winds, 58-mph sustained and 75-mph gusts as it rumbles past. Next on the itinerary is Misawa; Chanthu is forecast to pass just 8 miles east at 4 a.m. Friday, still packing sustained 35-mph winds and 52-mph gusts.
It could be more, it could be less, it could be further east of Japan, it could be further inland; Chanthu is but one day old and model guidance remains all over the lot. PST has an eye on it.
9 a.m. Sunday, Aug. 14, Japan time: Tropical Depression 09W now has a name (Chanthu), continues creeping slowly northeast and could become a tropical storm by Sunday afternoon.
6:15 p.m. Saturday, Aug. 13, Japan time: Joint Typhoon Warning Center has issued its first warning on as-yet-unnamed Tropical Depression 09W. At 3 p.m., it was 420 miles south of Iwo Jima and moving northeast at 14 mph, packing sustained 29-mph winds and 40-mph gusts at center.
JTWC's initial forecast track shows 09W wig-wagging in the general direction of the Tokyo-Kanto Plain area by Thursday evening, passing about 95 miles east of Yokosuka Naval Base at mid-evening Thursday, packing sustained 58-mph winds and 75-mph gusts at center.
But it's way early in the life of a newborn storm. PST will keep an eyeball on it.
If it becomes a named storm, it will be called Chanthu, Cambodian for flower.
11:15 a.m. Friday, Aug. 12, Japan time: A new tropical disturbance has formed about 430 miles west-northwest of Guam, which the models say should develop into a tropical cyclone, perhaps a typhoon. The question at this point: Where will it go? Dynamic model guidance is all over the lot. Some models suggest anywhere between following Omais and Conson; others have it curving sharply left toward Okinawa. We will see what we will see. PST has an eye on it.