winds of 305km / h and central pressure of 888hPa, is the most intense tropical cyclone ever recorded in April
The first typhoon of the season in the western Pacific has undergone such an intensification rate that it is a category 5 tropical cyclone record-breaking. The Tifone on Surigae; in fact, it reached maximum twenty of 305km/h with stronger gusts, while its central pressure plummeted to 888hPa, an extremely low value for any tropical system in the world (see maps in the scrolling gallery above). Surigae underwent an explosive intensification process from a Category 1 typhoon with 145km / h winds to a Category 5 monster with 305km / h winds in just 36 ore! This represents over double the rate of escalation needed to speak of explosive escalation.
Surigae has therefore become the most intense typhoon ever recorded in April and also the first tropical cyclone in the Northern Hemisphere to reach an intensity below 900hPa before May 1, breaking the previous record set by Typhoon Maysak in 2015.
The factors behind this explosive evolution
The main factors behind the formation of these explosive tropical cyclones are very often the warm waters of the sea and the wave known as Madden-Jullian Oscillation (MJO). Surface temperatures in the western Pacific are extremely high this spring, reaching approx +30°C. These ocean conditions strongly favor the explosive intensification of any tropical cyclone. This is the main reason Surigae exploded in a powerful Category 5 super typhoon.
Another factor that has recently increased the potential for tropical cyclone development in the western Pacific is the MJO wave, the largest and most dominant element of short-term tropical variability. The strong, deep MJO wave coincided with above-normal sea temperatures in the western Pacific, supporting strong convection in the area where super typhoon Surigae formed.
Surigae is the first category 5 tropical cyclone to occur in 2021. In a year, on average, about 18 tropical systems occur, reaching category 4 or 5 around the world.
The forecast for the Philippines
Surigae remains an extremely dangerous system, although its center is predicted to miss the Philippines. The system, however, will move a few hundred kilometers off the country’s coast. Based on the latest models, the northern sectors of the Philippines should be spared from Surigae’s worst impact. Models suggest that the super typhoon will veer towards the sea further north, so the chances of it hitting the northern sectors of Luzon directly are much lower now. In any case, they are still possible strong winds, heavy rains with the potential of floods and a dangerous storm surge.