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Tropical Storm Warning
ActiveTinian; Saipan
Status
In Progress
Started about 2 hours ago
Ends
Issued
Severity
Severe
Urgency
Immediate
Certainty
Likely
Details
...CHOI-WAN UPGRADED TO TYPHOON TO THE WEST OF PAGAN, MOVING NORTH... ...TYPHOON WARNING NOW IN EFFECT FOR ALAMAGAN IN THE CNMI...
.NEW INFORMATION... Choi-wan (26W) was upgraded to a typhoon.
A Typhoon Warning is now in effect for Alamagan in the CNMI.
.AREAS AFFECTED... This local statement provides information and recommended actions for people on Saipan, Tinian, Agrihan, Pagan and Alamagan in the Commonwealth of the Northern Marianas.
.Watches/Warnings... A Typhoon Warning is now in effect for Alamagan in the CNMI.
A Typhoon Warning remains in effect for Agrihan and Pagan in the CNMI.
A Tropical Storm Warning remains in effect for Tinian and Saipan in the CNMI.
A Typhoon Warning means that typhoon conditions are expected, including winds of 74 mph or more, with tropical storm force winds beginning within 24 hours. A Tropical Storm Warning means that tropical storm conditions, including winds of 39 to 73 mph, are expected within 24 hours.
A Flood Watch remains in effect for Tinian and Saipan. Please listen closely for any Flash Flood Warnings that might be in effect for your area.
Please check the latest public and marine forecasts for detailed information about additional hazards.
.STORM INFORMATION... At 1 AM ChST, the center of Typhoon Choi-wan (26W) was located near latitude 18.0N, longitude 144.7E. This was about 70 miles west of Pagan, 210 miles north-northwest of Saipan, and 310 miles north of Guam. Storm motion was north, 360 degrees, at 9 mph. Storm intensity was 80 mph.
.SITUATION OVERVIEW... Typhoon Choi-wan has begun to intensify more rapidly, and the typhoon force wind field has quickly come to encompass Alamagan and Pagan, as the latest forecast has expanded typhoon winds southward. So, a Typhoon Warning was issued for Alamagan, maintaining the Typhoon Warnings in effect for Pagan and Agrihan. Choi-wan is expected to make a slight turn toward the north- northeast this morning with little change in forward speed through Sunday, passing near to the west of Agrihan later this morning or early this afternoon. As it does so, Choi-wan is forecast to intensify through Sunday, becoming Category 2 as it passes Agrihan Saturday, then Category 3 Saturday night as it moves away. Intense rainbands wrapping into Choi-wan's center from the south continue to pummel the Marianas as they are pulled east to northeast, producing heavy downpours and strong gusts exceeding 60 mph.
Instructions
Stay indoors during heavy rain and tropical storm-force wind conditions associated with Typhoon Choi-wan (26W). Heed the advice of your local emergency managers and officials, and continue to monitor forecasts by the National Weather Service office in Tiyan, Guam. Remain in sturdy shelter until the all- clear is given.
Remain in suitable shelter, such as a cave or sturdy concrete structure. Shelter in place until the all-clear is given.
.WIND INFORMATION... Typhoon winds of 74 mph or more will continue for Alamagan and Pagan into this afternoon as Choi-wan moves north-northeast through the northern CNMI and strengthens, arriving at Agrihan later this morning. On either side of the typhoon-force winds, tropical storm force winds of 39 to 73 mph look to continue through at least Sunday morning.
.COASTAL INUNDATION AND SURF INFORMATION... Hazardous surf of 10 to 14 feet along north, south, and west facing reefs are expected to continue as the center moves north- northeast parallel to the northern CNMI through Saturday night, increasing by several feet during the time of nearest passage. As Choi-wan continues to strengthen, surf will continue to increase, likely becoming dangerous Saturday and Sunday. Significant coastal erosion and some coastal inundation is expected during Choi-wan's passage.
.OTHER STORM EFFECTS... Periods of rain, widespread heavy showers and scattered thunderstorms are expected through tonight, which is expected to produce rainfall totals of 8 to 14 inches by early Monday morning, with up to 20 inches of rainfall possible near the center of the system.
Data from the National Weather Service
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