Tag Archives: Rota

Tropical Storm Chan-hom Bringing Wind and Rain to Guam

Tropical Storm Chan-hom is passing through the Marianas and bringing gusty winds and rain to Guam and Rota.  At 11:00 p.m. EDT on Saturday the center of Tropical Storm Chan-hom was located at latitude 14.3°N and longitude 144.8°E which put it about 10 miles (15 km) west of Rota.  Chan-hom was moving toward the west-northwest at 8 m.p.h. (13 km/h).  The maximum sustained wind speed was 45 m.p.h. (70 km/h) and there were wind gusts to 60 m.p.h. (95 km/h).  The minimum surface pressure was 991 mb.

Despite being over warm water Chan-hom did not intensify on Saturday.  The circulation could be pulling in some drier air which is limiting the development of thunderstorms.  More thunderstorms developed near the inner core of Chan-hom late on Saturday.  There is not much vertical wind shear over the tropical storm.  If a well organized inner core forms, then intensification will be possible.  Chan-hom could become a typhoon after it moves west of the Mariana Islands.

The subtropical ridge steering Chan-hom is expected to continue to steer it toward the northwest during the next few days.  On its anticipated track Chan-hom could approach the southern islands of Japan in about four days.

Typhoon Dolphin Hits Guam and Rota

The core of Typhoon Dolphin moved over Guam and Rota on Friday.  Andersen Air Force Base reported northwesterly winds at 75 m.p.h. with gusts to 106 m.p.h. in one of its hourly observations.  The base also reported a Peak Wind of 86 knots (100 m.p.h.) in another observation.  The international airport on Guam reported a Peak Wind of 70 knots (80 m.p.h.).  At 5:00 p.m. EDT on Friday the center of Typhoon Dolphin was located at latitude 15.1°N and longitude 143.0°E which put it about 120 miles northwest of Guam.  Dolphin was moving toward the northwest at 15 m.p.h.  The maximum sustained wind speed was 125 m.p.h. and there were gusts to 155 m.p.h.  The minimum surface pressure was 941 mb.

Typhoon Dolphin is intensifying rapidly.  It is over water there the Sea Surface Temperature is near 29°C and the upper level winds are light.  It has a well formed eye and thunderstorms around the center are pumping out mass.  Upper level divergence is occurring and their are outflow channels to the northeast and southwest.  Dolphin could continue to intensify rapidly for another 24 hours.

Dolphin is near the western end of a subtropical ridge and it should gradually turn toward the north and then the northeast.  Its anticipated track will take it farther away from Guam, but it could approach Iwo To in about 72 hours as a significant typhoon.

Typhoon Dolphin Nearing Guam

Typhoon Dolphin is bringing wind and rain to Guam and Rota.  At 11:00 p.m. EDT on Thursday the center of Typhoon Dolphin was located at latitude 13.7°N and longitude 146.6°E which put it about 100 miles east of Guam.  Dolphin was moving toward the west-northwest at 16 m.p.h.  The maximum sustained wind speed was 110 m.p.h. and there were gusts to 130 m.p.h.  The minimum surface pressure was 952 mb.  A Typhoon Warning is in effect for Guam, Rota, Saipan and Tinian.  The Hurricane Intensity Index is 19.2, the Hurricane Size Index is 12.8 and the Hurricane Wind Intensity Size Index is 32.0.  The indices suggest that Dolphin is capable of producing regional serious damage.

The circulation of Dolphin became more symmetrical on Thursday and radar images from Guam show a circular eye and eyewall.  The thunderstorms near the center are generating upper level outflow.  Dolphin is moving over warm Sea Surface Temperatures and it is in an area where the upper level winds are relatively light.  The combination of better organization, warm water, little vertical wind shear suggest that further intensification is likely.

A subtropical ridge is steering Dolphin toward the west-northwest and that steering pattern is likely to continue for another day or so.  As Dolphin moves near the western end of the subtropical ridge, it is likely to turn more toward the north.  Eventually, when the typhoon moves farther north, westerly winds will turn it toward the northeast.

The core of Typhoon Dolphin will pass near Guam and Rota during the next few hours.  The northern portion of Guam and Rota will experience the strongest winds and heaviest rainfall, although much of Guam will experience the effects of Dolphin.  The core of the typhoon will likely pass south of Saipan and Tinian, but those islands will still get hit by rainbands rotating around the northern half of the circulation.

 

Typhoon Dolphin Still Moving Toward Guam

Typhoon Dolphin continued to moved toward the west-northwest in the direction of Guam on Wednesday.  At 11:00 p.m. EDT on Wednesday the center of Typhoon Dolphin was located at latitude 11.6°N and longitude 151.6°E which put it about 510 miles east-southeast of Guam.  Dolphin was moving toward the west-northwest at 15 m.p.h.  The maximum sustained wind speed was 105 m.p.h. and there were gusts to 125 m.p.h.  The minimum surface pressure was 956 mb.  A Typhoon Warning has been issued for Guam and Rota.  A Typhoon Watch and a Tropical Storm Warning has been issued for Saipan and Tinian.

Although the overall circulation of Dolphin remains well organized, many of the thunderstorms are located in a long spiral band that is trying to wrap around the center.  Some drier air may be wrapping around the western and southern sides of the circulation outside this band.  Dolphin is moving over warm Sea Surface Temperatures.  It is moving near the axis of an upper level ridge and the core of the typhoon is in an area with little vertical wind shear.  Except for the possible dry air, the conditions are favorable for further intensification.

Dolphin is being steered to the west-northwest by a subtropical ridge north of the typhoon.  The ridge is likely to continue to steer Dolphin in this direction for another day or two.  On the anticipated track Dolphin would approach Guam in 24 to 30 hours.  It could be a significant typhoon at that time.  After it passes Guam, Dolphin is expected to turn more toward the northwest as it moves around the western end of the subtropical ridge.