Hurricane (Typhoon) — Micronesia, Guam

2004-04-07 to 2004-04-09 · Micronesia, Guam

Wider weather episode

TYPHOON SUDALSudal began on the morning of April 4th as a 35 mph tropical depression about 130 miles west-southwest of Chuuk. Initially moving northwest, Sudal became a tropical storm that night as it moved over the island of Puluwat. Its northwest movement took Sudal between Satawal and Ulul around 1200 SST on the 5th, and continued until the morning of the 6th, when Sudal was perched about 290 miles southeast of Guam as a tropical storm with maximum winds of 65 mph. Sudal then turned west, becoming a typhoon that afternoon and coming to within 230 miles south-southwest of Guam around noon on the 7th. At this point, Sudal was still moving west, and it appeared it would continue on a west-northwest track, dealing no more than a glancing blow to the northernmost islands of Yap State. But Sudal instead turned west-southwest the evening of the 7th, passing about 40 miles south-southeast of Fais the next morning. On the morning of April 9th, Typhoon Sudal turned west-northwest again, dealing Yap a severe blow as it passed just south of the main island. Chuuk State:After moving directly over Puluwat as a 40 mph tropical storm at 0100 SST on April 5th, Sudal passed 50 miles west-southwest of Ulul around 1200 SST. At Puluwat, the highest sustained wind was 23 mph from the west at 0700 SST. At Ulul, 6.68" of rain fell in the 24 hours ending at 1700 SST on the 4th. Storm Damage in Chuuk State: Coastal inundation at Ulul was 2 feet or less, destroying some cultivated subsistence crops and contaminating the water supply, and beach erosion was slight. Some poorly-built structures lost their roofs. No deaths or injuries were reported.Yap State:In eastern Yap State, Sudal passed 115 miles east-northeast of Satawal with maximum sustained winds of 45 mph at 1300 SST on April 5th, then intensified over the next day and a half, reaching 85 mph as it passed 165 miles north of Woleai on the morning of the 7th at 0700 SST. Sudal continued to intensify, reaching 110 mph as it passed 40 miles south-southeast of Fais at 0900 SST April 8th, and 115 mph as it passed 65 miles south-southeast of Ulithi that afternoon at 1330 SST. Only hand-held wind-measuring equipment is available at Satawal and Woleai, where winds of 25 mph gusting to 40 mph were estimated as Sudal passed. At Ulithi, the automated station recorded a highest sustained wind of 58 mph from the east-northeast at 2100 SST the evening of the 8th, followed two hours later by the peak gust of 82 mph. The lowest pressure of 991.6 mb was recorded at 1600 SST that afternoon. Rainfall was heavy, with 6.34 inches recorded in the 24 hours ending the 9th at 0100 SST. No measuring equipment exists on Fais, but conditions there were likely similar to those on Ulithi.It was for the island of Yap that Sudal reserved its full fury on the morning of April 9th. As the center of Sudal's eye passed about 7 miles south of Yap's southern tip around 1000 SST, the northern eye wall raked the island with winds as high as 115 mph for roughly 4 hours. At the Yap Weather Service Office, located at the airport, the highest 2-minute wind speed of 69 mph was recorded several times on the morning of the 9th: from the north-northeast at 0757 SST, from the northeast at 0950 SST, and from the southeast at 1157 SST. The peak gust of 112 mph from the southeast was recorded at 1135 SST. However, a NWS assessment team determined from damage on the south end of Yap Island that maximum sustained winds there were likely in the low typhoon category 3 range of 115 to 120 mph gusting to 140 mph. The lowest sea-level pressure was 958.5 mb at 1050 SST. Rainfall at the airport totaled 5.24 inches in the 24 hours ending at 2200 SST on the 9th, while 7.88 inches fell in the 48 hours ending at the same time. A brief eye passage was observed on the extreme southern tip of Yap.At the time of its closest approach to Yap, Sudal was also passing 70 miles north-northeast of the tiny island of Ngulu. No functioning instrumentation exists on Ngulu, but sustained winds likely reached around 50 mph from the northwest, with gusts to around 70 mph, as Sudal passed. No rainfall measurements are available, but from enhanced infrared imagery it is probable that 6 to 9 inches of rain fell during Sudal's passage. Storm Damage in Yap State: In spite of Sudal's intensity and the massive damage it wrought on Yap, no deaths or serious injuries were reported anywhere in Yap State. Damage for individual islands or island groups is summarized below:Satawal, Woleai, Faraulep, Ifalik, Eauripik, Lamotrek and surrounding atolls: Coastal inundation was 1 to 2 feet, except 2 to 3 feet at Faraulep, with moderate beach erosion. Many cultivated subsistence crops such as breadfruit and coconuts were damaged or destroyed by salt spray, and some water sources were contaminated by salt. Fais: Because Fais is an elevated island, coastal inundation was not significant, but 14 to 18 foot surf brought moderate to severe beach erosion. Water sources were partly contaminated by sea spray. Some poorly-built structures were damaged, especially wood and tin roofs. Ulithi: Coastal inundation of 2 to 3 feet and surf ranging from 14 to 18 feet resulted in moderate to severe beach erosion and contamination of some water sources. Most subsistence crops were destroyed by inundation and sea spray, and a few trees were lost as well. Some wood and tin roofs were damaged, and some poorly-built structures were lost.Yap: Since Yap itself was pounded by Sudal's eye wall for 4 or 5 hours, it suffered by far the worst damage of any location in Yap State. Over 90% of the buildings and other structures were damaged or destroyed. Out of 1700 residences, 700 were destroyed. Of the remaining 1000 homes, only 41 were undamaged. The hospital, airport, most government facilities, and the water, power and communications systems were all severely damaged. Wooden homes suffered the worst, while concrete structures fared much better. Along the eastern and southern coasts, the storm surge destroyed the many wooden homes built along the shoreline, and severely damaged the seawall. Of the 8,000 or so residents on Yap, about 1500 were in shelters, of which about 1000 were homeless. Subsistence crops were almost totally destroyed, and the ground in coastal areas was saturated with salt water, making it unsuitable for cultivation. A storm surge of 8 to 12 feet, along with pounding surf as high as 22 feet, severely damaged the coral reefs, one of Yap's main tourist attractions.Ngulu: Little information is available from Ngulu, other than that four of Ngulu's eight water storage tanks were destroyed. Otherwise, damage there was likely similar to that experienced at Ulithi.

Source: NOAA Storm Events Database, event_id 5422480. Narrative written by the NWS forecast office that issued the report.