Typhoon Karen

Typhoon Karen was the most powerful tropical cyclone to strike the island of Guam, and has been regarded as one of the most destructive events in the island's history. It was first identified as a tropical disturbance on November 6, 1962, well to the southeast of Truk. Over the following two days, the system tracked generally northward and quickly intensified. Karen became a tropical storm late on November 7, and within two days it explosively intensified into a Category 5-equivalent super typhoon on the Saffir–Simpson scale. Turning westward, the typhoon maintained its intensity and struck Guam with winds of 280 km/h (170 mph) on November 11. Once clear of the island, it strengthened slightly and reached its peak intensity on November 13 with winds of 295 km/h (183 mph) and a barometric pressure of 894 mb (hPa; 26.40 inHg). The storm then gradually turned northward as it weakened, brushing the Ryukyu Islands on November 15, before moving east-northeastward over the open waters of the Pacific. Karen continued to weaken and transitioned into an extratropical cyclone on November 17 before losing its identity the following day between Alaska and Hawaii.

Karen devastated Guam with wind gusts estimated up to 280 km/h (170 mph). Ninety-five percent of homes were damaged or destroyed, leaving at least 45,000 people homeless. Communication and utilities were crippled, forcing officials to set up water distribution centers to prevent disease. Total losses on the island amounted to $250 million. Despite the severity of the damage, only 11 people were killed. In the wake of the storm, a massive relief operation evacuated thousands to California, Hawaii, and Wake Island. Thousands more were sheltered in public buildings, and later tent villages, for many months. More than $60 million in relief funds were sent to Guam over the following years to aid in rehabilitation. Though the storm was devastating, it spurred new building codes and a revitalized economy.

On November 6, 1962, a tropical disturbance was identified over the Pacific Ocean several hundred miles south-southeast of Truk, in the Federated States of Micronesia, by the Joint Typhoon Warning Center (JTWC). Tracking northwestward, the disturbance intensified and was classified as a tropical depression early on November 7. Later that day, the system passed to the east of Truk and turned due north before attaining gale-force winds. Around 18:00 UTC, the JTWC issued their first advisory on Tropical Storm Karen, the 27th named storm of the 1962 season. Several hours later, a reconnaissance mission into the storm revealed a partially closed 35 km (22 mi) wide eye. Over the following 30 hours, Karen underwent a period of explosive intensification as its eye became small and increasingly defined. Between 00:00 UTC on November 8 and 03:40 UTC on November 9, Karen's barometric pressure plummeted from 990 to 899 hPa (29.23 to 26.55 inHg), a drop of 91 hPa (2.69 inHg). At the end of this phase, Karen featured an 8 to 10 km (5 to 6 mi) wide eye and had estimated surface winds of 295 km/h (183 mph), ranking it as a modern-day Category 5-equivalent super typhoon on the Saffir–Simpson hurricane scale.

After attaining this initial peak intensity on November 9, Karen weakened somewhat as it gradually curved west-northwestward. By 15:14 UTC, the storm began to undergo an eyewall replacement cycle as a larger secondary eyewall, approximately 64 km (40 mi) in diameter, started developing. Although the storm's winds failed to drop significantly, Karen's central pressure rose to 919 hPa (27.14 inHg) during this phase. Accelerating slightly, Karen tracked steadily west-northwestward towards Guam. By November 11, the system had regained a well-defined eye and deepened once more. Between 12:10 and 12:35 UTC on November 11, the 14 km (9 mi) wide eye of Karen passed directly over southern Guam. At this time, the storm was estimated to have had winds of 280 km/h (170 mph), which would have made it the most intense typhoon to strike the island since 1900. However, years of post-storm analyses have indicated that it may have been somewhat weaker when it passed over Guam. At the Weather Bureau station at the north end of Guam, a pressure of 942.4 hPa (27.83 inHg) was measured. Farther south at Anderson Air Force Base, 939.7 mbar (939.7 hPa; 27.75 inHg) was recorded. The lowest verified pressure was 931.9 hPa (27.52 inHg) at the Agana Naval Air Station. Closest to the eye was Naval Magazine where a pressure of 907.6 hPa (26.80 inHg) was estimated but never verified.

Continuing west-northwestward, Karen attained its peak intensity on November 13, with a central pressure of 894 hPa (26.40 inHg). Between November 13 and 14, Karen gradually turned towards the north as it underwent another eyewall replacement cycle. During this time, Karen finally weakened below Category 5 status as its winds dropped below 251 km/h (156 mph). This marked the end of its near-record 4.25-day span as a storm of such intensity, second only to Typhoon Nancy of 1961 which maintained Category 5 status for 5.5 days. Over the following days, the typhoon's structure gradually became disorganized, with its eye no longer well-defined by November 15. By this time, Karen began accelerating northeastward and later east-northeastward over the open ocean. The combination of its rapid movement and entrainment of cold air into the circulation ultimately caused the system to transition into an extratropical cyclone on November 17. The remnants of Karen continued tracking east-northeast and were last noted by the JTWC on November 18 roughly halfway between the southern Aleutian Islands and northern Hawaiian Islands.

"It was just hell. It was total destruction. It looked to me like a whole army of workers with big scythes had just gone across the whole place and chopped down everything they could see. Everything was lying down–smashed. Even the forests were lying down."

Following the identification of a tropical disturbance on November 6, a level four Typhoon Condition of Readiness (TCOR), the lowest level of alert, was raised for Guam. By November 8, three days prior to Karen's arrival, this was raised to level three, prompting residents and military personnel to stock up on supplies. A public announcement was made that day as well, warning residents that the typhoon would likely strike the island. At 9:00 p.m. on November 10 (11:00 UTC), a level two TCOR was put in place for Guam and a typhoon emergency was declared. Buildings were boarded up and emergency supplies were distributed. By 8:00 a.m. (22:00 UTC on November 10), this was raised to level one, the highest level of warning. At this time, USS Haverfield, USS Brister, USS Wandank, and USS Banner sought refuge from the storm over open waters. All personnel on the island were ordered to evacuate to typhoon-proof shelters and emergency rations were prepared. Strategic air command planes stationed on the island were relocated to avoid damage. Many residents on the island sought refuge in government buildings designed to withstand powerful storms while others evacuated to Wake Island. Roughly 24 hours after the typhoon's passage, all warnings were discontinued.

Striking Guam as a Category 5-equivalent typhoon, Karen produced destructive winds across much of the island. With the eye passing over the southern tip of the territory, the most intense winds were felt over central areas. Wind gusts over the southern tip of Guam were estimated to have peaked around 185 km/h (115 mph). Due to the extreme nature of these winds, all anemometers on the island failed before the most intense portion of the storm arrived, and there were no measurements of the strongest winds; however, post-storm reports estimated that sustained winds reached 250 km/h (160 mph) in some areas. The highest measured gust was 240 km/h (150 mph) at a United States Navy anemometer on Nimitz Hill just before 11:00 UTC on November 11, roughly two hours before the typhoon's eye passed the station. Based on this measurement, a study in 1996 estimated that gusts peaked between 280 and 295 km/h (174 and 183 mph) over southern areas of the island. Newspaper reports indicated that a gust of 272 km/h (169 mph) was measured on the island before the anemometer was destroyed. There was also an unverified report of a 333 km/h (207 mph) wind gust. Nearly all measurements of rainfall during the typhoon were lost; the only known total is 197 mm (7.76 in) at the Weather Bureau station for the period of November 10–12.