Typhoon June (1975)
Typhoon June, known in the Philippines as Typhoon Rosing, was an extremely powerful tropical cyclone that is tied with Typhoon Nora in 1973 as the third-most intense tropical cyclone on record. The twenty-third named storm, fourteenth typhoon and third and final super typhoon of the 1975 Pacific typhoon season, June originated from a tropical disturbance moving westward over the Caroline Islands on November 14, organizing into a tropical depression two days later. The storm initially moved slowly due to weak steering forces from the system's close proximity to the equator, but began to move northwards on November 18. Simultaneously, June began to experience explosive intensification, with the central pressure falling by in 24 hours. On November 19, a weather reconnaissance aircraft from the 54th Weather Reconnaissance Squadron of the United States Air Force measured a pressure of at the edge of the eye. This made June the most intense tropical cyclone observed on record at the time, surpassing the pressure measured in Typhoon Ida in 1958 and tying it with Nora in 1973. Both have since been surpassed by 2015's Hurricane Patricia and 1979's Typhoon Tip. June continued to move northward through the Philippine Sea, weakening as it did so. The storm began accelerating into the westerlies before becoming extratropical on November 24. The remnants passed over the Aleutian Islands, before being last noted over Siberia, where it ultimately dissipated.
Despite the storm's extreme intensity, damage was relatively limited in Guam, and no casualties were caused by June, primarily as a result of staying west of the island chain, although storm surge was still a hazard that caused problems. June caused significant flooding and wind damage on Guam, some more localized then other areas, with total losses estimated at $1.3 million. At least 29 people were left homeless as a result. In Yap, the storm resulted in flood damage to property and crops on several atolls.
Meteorological history
June's origins can be traced back on November 14, when a tropical disturbance formed over the island of Micronesia. Located within very weak steering currents initially, the disturbance did not move much and meandered slowly westward, gradually before consolidating into a tropical depression at 06:00 UTC on November 16, about south of Guam. A sprawling storm, satellite data suggested the cyclone intensified into a tropical storm shortly afterwards about six hours later, with the Joint Typhoon Warning Center assigning it the name June. The storm remained nearly quasi-stationary throughout the day on November 17 as it approached a weakness in a ridge to its north, strengthening at a steady pace, while being constantly surveyed by the Hurricane Hunters of the 54th Weather Reconnaissance Squadron. An approaching trough from the west began to steer June to the north the following day, at which point June then intensified into a typhoon.A small, -wide eye developed, and, attributed to very favorable environmental conditions, June commenced a period of explosive intensification on November 18. The central pressure proceeded to drop in a day, with a drop recorded in only 11 hours, while the JTWC noted that the maximum sustained winds had increased to 295 km/h, making it a Category 5-equivalent super typhoon on the Saffir–Simpson scale. Very early on November 19, at 08:13 UTC, a Hurricane Hunter aircraft within the eye of the extremely powerful typhoon measured a then-record low sea level pressure of via dropsonde. The sonde did not hit the center of the eye, so the lowest central pressure is assessed as having been slightly lower, at, tying it with Nora in 1973 as the third-most intense tropical cyclone on record – with Hurricane Patricia of 2015 and Typhoon Tip in 1979 achieving lower pressures. Subsequent studies observed that as a result of the sonde missing the center, the true pressure of June might have been even lower then estimated. The Hurricane Hunters also observed frequent lightning within the eyewall, further signaling its extreme intensity. At the time of its peak, June was located about west of Guam, its closest approach to the island.
After peaking, the small eye of June soon clouded over and filled, as an eyewall replacement cycle soon commenced later on November 19. The size of the powerful typhoon also increased as June towards more westward that night, with tropical storm-force winds extending out from the center. During the eyewall cycle, June became the first instance from Hurricane Hunters to observe three concentric eyewalls in a tropical cyclone. June temporarily plateaued in intensity during the next day, before unfavorable conditions caused the typhoon to resume weakening, falling below Category 5-equivalent intensity on November 21. Accelerating north and then northeast into the westerlies at forward speeds up to, more pronounced weakening took place as June began losing tropical characteristics due to very strong wind shear. June became extratropical on November 22, and the JTWC issued their last advisory. The remnants of June then turned northwards, affecting the Aleutian Islands, and then far northeastern Siberia before it was last noted over that region on November 23.