Tag Archives: Iwo To

Typhoon Champi Bringing Wind and Rain to Iwo To

A portion of the northern eyewall of Typhoon Champi is over Iwo To and it is bringing wind and rain to the island.  A weather station on Iwo To is reporting east-northeasterly winds at 47 m.p.h. (75 km/h) with gusts to 73 m.p.h. (118 km/h).  At 11:00 p.m. EDT on Wednesday the center of Typhoon Champi was located at latitude 23.8°N and longitude 141.6°E which put it about 75 miles (120 km) south of Iwo To.  Champi was moving toward the northeast at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 145 m.p.h. (230 km/h).  The minimum surface pressure was 945 mb.

The inner core of Typhoon Champi became much more well organized during the past 12 hours and it now has a clear circular eye that is approximately 30 miles (48 km) across.  The eye is surrounded by a ring of strong convection which contains the strongest winds.  The core is also generating upper level divergence which is pumping out mass.

Typhoon Champi will be in a favorable environment for another 12 hours.  It is moving over water where the Sea Surface Temperature is near 28.5°C.  The upper level winds are light and there is not much upper level divergence.  Champi could intensify further on Thursday, but it will move into a less favorable environment when it moves farther north.  Once Champi gets north of latitude 27°N, it will move over cooler SSTs.  Typhoon Champi will start to encounter strong upper level westerly winds at about the same time.  The combination of cooler water and more vertical wind shear will steadily weaken Champi.

Typhoon Champi is moving northward around the western end of a subtropical ridge.  When it reaches the upper level westerly winds, those winds will accelerated Champi toward the east-northeast until it transforms into an extratropical cyclone over cooler waters.  On its anticipated track the center of Champi will pass southeast of Iwo To, but it will bring strong winds and rain to that island for another 12 hours or so.

Strong Typhoon Champi Intensifies South of Iwo To

Typhoon Champi intensified rapidly on Sunday and it reached the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale.  At 5:00 p.m. EDT on Sunday the center of Typhoon Champi was located at latitude 20.3°N and longitude 140.3°E which put it about 325 miles (525 km) south-southwest of Iwo To.  Champi was moving toward the north-northeast at 4 m.p.h. (6 km/h).  The maximum sustained wind speed was 145 m.p.h. (235 km/h) and there were wind gusts to 175 m.p.h. (280 km/h).  The minimum surface pressure was 924 mb.

The circulation of Typhoon Champi is very well organized.  It has a well defined eye and there could be a rainband wrapping around the center to create concentric eyewalls.  Multiple spiral bands are revolving around the center of circulation.  Winds to typhoon force extend out 40 miles (65 km) from the center.  Well developed upper level divergence is pumping out mass in all directions.

Typhoon Champi is moving over water where the Sea Surface Temperature is near 29°C.  The winds in the upper levels are relatively light and there is not much vertical wind shear.  Champi will remain in a favorable environment for another 24 to 48 hours.  Eyewall replacement cycles could cause fluctuations in intensity during that period.  When it moves north of latitude 25°N, Champi will encounter the upper level westerly winds in the middle latitudes which will cause significant vertical wind shear.  Champi will weaken as the wind shear increases.

Champi is moving slowly northward as it curves around the western end of a subtropical ridge.  It will continue to move northward for another day or two.  When it begins to be affected by the upper level westerly winds, Champi will accelerate toward the northeast.  On its anticipated track Typhoon Champi will approach Iwo To in 48 to 60 hours.  Champi will be a large, strong typhoon at that time.

Tropical Storm Champi Passing Through the Northern Marianas

Tropical Storm Champi is bringing gusty winds and heavy rain as it moves through the Northern Marianas.  At 11:00 p.m. EDT on Thursday the center of Tropical Storm Champi was centered near latitude 15.9°N and longitude 146.3°E which put it about 80 miles (135 km) east-northeast of Saipan.  Champi was moving toward the west at 19 m.p.h. (31 km/h).  The maximum sustained wind speed was 70 m.p.h. (115 km/h) and there were wind gusts to 85 m.p.h. (135 km/h).  The minimum surface pressure was 980 mb.  A Tropical Storm Warning remains in effect for Rota, Tinian, Saipan, Alamagan, Pagan and Agrihan.  The weather station at the airport on Saipan was reporting southwesterly winds at 46 m.p.h. (74 km/h) with gusts to 78 m.p.h. (126 km/h).

Although an upper level ridge north of Champi continued to cause vertical wind shear over the tropical storm, it slowly intensified on Thursday.  More thunderstorms formed near the center of circulation and those storms are generating more upper level divergence.  The core of the circulation is consolidating and more spiral bands are forming outside the core.  Champi is on the threshold of becoming a typhoon.  It is moving over water where the Sea Surface Temperature is near 29°C.  Champi is likely to move into an area where the upper level winds are lighter during the weekend and it will continue to intensify during the next several days.

A subtropical ridge is steering Champi toward the west and that motion is expected to continue for the next 12 to 24 hours.  After that time Champi will reach the western end of the ridge and turn toward the north.  Champi could be a strong typhoon south of Iwo To in about three days.

Tropical Storm Champi Intensifies, Warnings Issued for Northern Marianas

Tropical Storm Champi intensified on Wednesday and the National Weather Service issued watches and warnings for the northern Marianas.  At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Champi was located at latitude 15.5°N and longitude 151.9°E which put it about 450 miles (730 km) east of Saipan.  Champi was moving toward the west-northwest at 13 m.p.h. (21 km/h).  The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 75 m.p.h. (120 km/h).  The minimum surface pressure was 984 mb.  Tropical Storm Warnings have been issued for Rota, Tinian, Saipan, Alamagan, Pagan and Agrihan.  A Typhoon Watch has been issued for Alamagan, Pagan and Agrihan.

The circulation of Tropical Storm Champi is still organizing.  An upper level ridge north of the tropical storm is causing easterly winds to blow over the top of Champi.  The resulting vertical wind shear is causing most of the stronger thunderstorms to form in the western half of the circulation.  Champi is over water where the Sea Surface Temperature is near 29°C.  The vertical wind shear will inhibit intensification on Thursday, but Champi could reach typhoon intensity within 24 hours.  It is expected to move into an area where the upper level winds are lighter on Friday and the rate of intensification could increase.

A subtropical ridge is steering Champi on a track that is a little north of due west.  That general motion is expected to continue for the next several days.  Champi will reach the western end of the subtropical ridge and turn toward the north later in the weekend.  On its anticipated track Champi will approach the northern Marianas in 24 to 30 hours.  It could bring strong winds and heavy rain to those islands.  Since the strongest thunderstorms are west of the center of circulation, conditions could start to deteriorate on some of the islands in less than 24 hours.

Tropical Storm Choi-Wan Organizing Southeast of Japan

Tropical Storm Choi-Wan exhibited better organization on Monday as it moved southeast of Japan.  At 5:00 p.m. EDT on Monday the center of Tropical Storm Choi-Wan was located at latitude 23.4°N and longitude 151.4°W which put it about 615 miles (990 km) east of Iwo To.  Choi-Wan was moving toward the west-northwest at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 70 m.p.h. (110 km/h) and there were wind gusts to 85 m.p.h. (135 km/h).  The minimum surface pressure was 981 mb.

Tropical Storm Choi-Wan has a broad center of circulation without a tight inner core.  A rainband appears to be trying to wrap entirely around the broad center and other rainbands are forming outside the center.  Satellite images seem to indicate that Choi-Wan is slowly organizing.  Thunderstorms near the center of circulation are producing upper level divergence.

The environment favors intensification.  Choi-Wan is over water where the Sea Surface Temperature (SST) is near 29°C.  The upper level winds are light and there is little vertical wind shear.  Upper level outflow channels appear to be developing northeast and southwest of Choi-Wan.  If the tropical storm had a tight core, rapid intensification would be likely.  With a broader center of circulation, intensification will be more gradual.  Choi-Wan could become a typhoon on Tuesday.  When Choi-Wan moves farther north it will move over cooler SSTs and the wind shear will increase, which will weaken it.

Tropical Storm Choi-Wan is moving around the western end of a subtropical ridge.  The ridge is expected to steer Choi-Wan mainly toward the north during the next several days.  On its anticipated track, Choi-Wan could approach some of the northern islands of Japan in about three days.  Choi-Wan could be a tropical storm or a strong extratropical low pressure system at that time.

Typhoon Krovanh Nearing Iwo To

Typhoon Krovanh continued to intensify on Thursday and it is now the equivalent of a Major Hurricane.  At 11:00 p.m. EDT on Thursday the center of Typhoon Krovanh was located at latitude 24.1°N and longitude 142.5°E which put it about 105 miles (170 km) southeast of Iwo To.  Krovanh was moving toward the north-northwest at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 150 m.p.h. (240 km/h).  The minimum surface pressure was 935 mb.  The weather station on Iwo To is currently reporting sustained winds of 33 m.p.h. (53 km/h) with wind gusts to 48 m.p.h. (77 km/h).

Typhoon Krovanh has probably reached its peak intensity.  It may be pulling in some drier air from the northwest.  It also looks like an upper level trough near Japan is beginning to cause southwesterly winds over the top of the typhoon.  There is a gap in the eyewall on the south side and clouds are beginning to obscure the eye on satellite imagery.  Vertical wind shear will increase as Krovanh moves farther north and it gets closer to the upper level trough.  Krovanh will also start to move over cooler Sea Surface Temperatures which will increase the rate at which it weakens.

Typhoon Krovanh is moving around the western end of the subtropical ridge that has been steering it.  It will start to turn toward the northeast on Friday as the upper level trough begins to steer the typhoon.  On its anticipated track the center of Krovanh will pass within about 50 to 60 miles (80 to 95 km) of Iwo To during the next few hours and then it will be very near Chichi Jima in about 18 hours.  Krovanh could cause gusty winds, heavy rain and large waves as it passed near those two islands.

Krovanh Becomes a Typhoon Southeast of Iwo To

Krovanh continued to intensify rapidly on Wednesday and it reached typhoon status.  At 11:00 p.m. EDT on Wednesday the center of Typhoon Krovanh was located at latitude 21.5°N and longitude 144.5°E which put it about 330 miles (530 km) southeast of Iwo To.  Krovanh was moving toward the northwest at 13 m.p.h. (21 km/h).  The maximum sustained wind speed was 90 m.p.h. (145 km/h) and there were wind gusts to 115 m.p.h. (185 km/h).  The minimum surface pressure was 961 mb.

Typhoon Krovanh remains in a very favorable environment.  It is over water with warm Sea Surface Temperatures and the upper level winds are light.  The absence of significant vertical wind shear has allowed upper level divergence to continue to pump away mass in all directions.  The structure of the inner core of Krovanh improved as it intensified and the typhoon now has a well developed eye surrounded by a nearly complete eyewall.  The favorable environment could allow Krovanh to intensify for another 24 to 36 hours.  When the typhoon begins to approach latitude 30°N, it will begin to be affected by the upper level westerly winds in the middle latitudes.  The increased vertical wind shear will begin to weaken Krovanh.

Typhoon Krovanh is moving around the western end of a subtropical ridge.  The ridge should steer Krovanh toward the northwest for another 24 hours.  When it reaches the western end of the ridge, the typhoon will start moving toward the north.  As the upper level westerly winds start to affect Krovanh, those winds will accelerate it toward the northeast.  On its anticipated track Krovanh could be approaching Iwo To in about 24 hours and it could be near Chichi Jima in about 36 hours.  Krovanh could be a strong typhoon when it passes those islands.

Tropical Storm Krovanh Organizing Quickly Near Northern Marianas

The circulation around Tropical Storm Krovanh is organizing quickly as it passes near the northern Marianas.  At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Krovanh was located at latitude 19.3°N and longitude 148.1°E which put it about 170 miles (275 km) east-northeast of Agrihan in the northern Mariana Islands.  Krovanh was moving toward the northwest at 11 m.p.h. (18 km/h).  The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 65 m.p.h. (105 km/h).  The minimum surface pressure was 995 mb.  A Tropical Storm Watch has been issued for Alamagan, Pagan and Agrihan in the northern Marianas.

The circulation near the center of Krovanh organized quickly on Tuesday.  A primary spiral rainband wrapped around the southern side of the center and an eyelike feature has appeared intermittently on visible satellite imagery.  Additional rainbands are developing around the circulation.  The thunderstorms near the core of the tropical storm are producing upper level outflow in all directions which is pumping out mass and is allowing the surface pressure to decrease.

Tropical Storm Krovanh is moving over water where the Sea Surface Temperature is near 30°C.  Upper levels winds are light and there is little vertical wind shear.  The environment is very favorable for further intensification and rapid intensification is likely.  Krovanh could become a typhoon within 24 hours and it could be a strong typhoon within several days.

A subtropical ridge located northeast of Krovanh is steering the tropical storm toward the northwest.  That general steering pattern is expected to continue for the next 48 hours.  After that time Krovanh will reach the western end of the subtropical ridge and it will turn toward the north.  On its anticipated track Krovanh will pass through the extreme northern Marianas on Wednesday and it be approaching Iwo To in about 48 hours.  Krovanh could be a strong typhoon at that time.

Typhoon Atsani Reaches Equivalent of Cat. 5 Hurricane

Typhoon Atsani intensified over the past 24 hours and it is now the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale.  At 8:00 a.m. EDT on Wednesday the center of Typhoon Atsani was located at latitude 19.6°N and longitude 151.3°E which put it about 1340 miles (2160 km) southeast of Tokyo, Japan.  Atsani was moving toward the northwest at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 160 m.p.h. (260 km/h) and there were wind gusts to 185 m.p.h. (300 km/h).  The minimum surface pressure was 918 mb.

Atsani is in an environment that is very favorable for tropical cyclones.  The Sea Surface Temperature (SST) is near 28°C.  The upper level winds are very light and there is almost no vertical wind shear.  Upper level divergence is pumping out mass in all directions and Atsani has a very circular appearance with a large eye evident on satellite imagery.  There are more rainbands and thunderstorms in the southern half of the circulation which is probably the result of warmer, moister air in area.

Atsani could maintain its current intensity for another 24 hours or so, although an eyewall replacement cycle will cause weakening if one occurs.  In another day or two the typhoon will start to move over cooler SSTs.  In addition as Atsani moves northward, it will start to be affected by the upper level westerlies in the middle latitudes.  Those winds will increase wind shear and weaken Atsani further.

Atsani is moving around the western end of a subtropical ridge which is steering it toward the northwest.  That general motion is expected to continue for another couple of days.  When Atsani reaches the western end of the ridge it will start moving toward the north.  Eventually, the upper level westerly winds will accelerate Atsani off to the northeast.  On its anticipated track Atsani would pass north of the Marianas and northeast of Iwo To.  At the current time the center of Atsani is forecast to pass about 100 miles east of ChiChi Jima.  However, a slight deviation of the track toward the west could bring Atsani closer to Chichi JIma and Iwo To.

 

Typhoon Dolphin Is Bringing Wind and Heavy Rain to Iwo To

Even though the center of Typhoon Dolphin is still over 100 miles from Iwo To, it is bringing wind and heavy rain to that island.  The most recent surface observation reported southeast winds at 43 m.p.h. with gusts to 66 m.p.h.  At 11:00 p.m. EDT on Monday the center of Typhoon Dolphin was located near latitude 24.6° and longitude 139.7°E which put it about 140 miles west-southwest of Iwo To.  Dolphin was moving toward the northeast at 10 m.p.h.  The maximum sustained wind speed was 85 m.p.h. and there were gusts to 105 m.p.h.  The minimum surface pressure was 967 mb.

Dolphin will continue to move over cooler Sea Surface Temperatures as it moves farther north.  It will also encounter strong upper level westerly winds, which will increase vertical wind shear.  So, Typhoon Dolphin will weaken steadily on Tuesday.  It will eventually transition into an extratropical cyclone as it passes southeast of Japan.

Upper level westerly winds are steering Typhoon Dolphin toward the northeast.  It is expected to accelerate toward the northeast on Tuesday.  On its anticipated track the center of Dolphin will pass northwest of Iwo To during the next few hours.  It could pass very near Chichi Jima on Tuesday and bring strong wind and heavy rain.