Super Typhoon Mawar strengthens into most powerful storm on Earth in more than 2 years

Super Typhoon Surigae exploded from a Category 2 to a Category 5 in one day

The storm passed just north of Guam as a Category 4 on Wednesday, lashing the island with winds in the Category 2 range and flooding rains. Now it’s resurged to Category 5 force, and is among the top 10 strongest storms to occur globally since 2000.

Mawar matches the strongest storms ever observed worldwide during the month of May, and beats out anything seen globally in 2022. While the storm is a product of natural randomness, it fits into a pattern of more intense storms, and storms more prone to rapid intensification, in an era earmarked by warming oceans and human-induced climate change.

An extreme storm of historic strength

As of Friday morning Eastern time, Mawar had winds of 145 knots, or 165 mph. It was perfectly symmetrical on satellite, portending extreme fury surrounding an eerily calm and hollowed-out eye. Gravity waves, or undulations in the top of the cloud cover, can be seen propagating through Mawar’s overcast; that’s where the extreme upward motion of the eyewall has sent density ripples through the tropopause, or the “ceiling” of the lower atmosphere.

Since 1950, only eight typhoons in the West Pacific basin have attained Category 5 equivalent status during the month of May, with winds of 157 mph or greater. Mawar is the ninth.

On Thursday night Eastern time, the U.S. Joint Typhoon Warning Center assessed Mawar’s maximum sustained eyewall winds at 160 knots, or 185 mph. Gusts were pegged at 215 mph. There exists only one other West Pacific typhoon in the National Weather Service’s database to become that strong during the month of May — Phyllis, which briefly nicked 185 mph intensity on May 29, 1958. In fact, no other storms worldwide have done that during the month of May.

Throughout the entire year, only 13 other typhoons have reached 185 mph strength since 1979.

Equally staggering is Mawar’s air pressure, which bottomed out around 897 millibars on Friday morning Eastern time. Average sea level air pressure is 1015 millibars. Air pressure represents the weight of the air over a given location. Lower air pressure signifies a stronger low-pressure system. The air pressure inside Mawar is equivalent to that atop a 3,000-foot mountain.

That means roughly a tenth of the atmosphere’s air is “missing” from the center of Mawar, spurring the powerful inward suction responsible for the storm’s extreme winds.

Mawar came close to ravaging Guam earlier this week, but a pair of shifts prevented calamity from striking the island. The storm underwent an “eyewall replacement cycle,” during which the inner radius of maximum winds disintegrates as a new eyewall forms, which led to a brief faltering in intensity. The storm also skirted north of Guam and entrained a filament of dry air into its circulation, reducing the force of the winds that buffeted Guam.

Still, a gust of 105 mph was clocked at Guam’s International Airport during the 7 p.m. hour Wednesday night local time. The airport received 12.3 inches of rain between May 23 and 24, while northern parts of the island topped 27 inches.

Where Mawar is going?

Confidence is high that Mawar will continue drifting to the west, but its forward speed and strength remain uncertain. That’s because there are no obvious dominant features that will influence Mawar’s motion more than others.

A pair of high-pressure systems will flank Mawar — one to its east over the west central Pacific, and one to the west over China. It’s unclear which of the two will be stronger. High-pressure domes are like magic force fields suppressing Mawar’s approach. The cyclone may try to slowly thread north between the two, like a pinball between two obstacles.

That said, the pair of highs could slow Mawar’s recurvature, or northward curve, to a crawl, potentially leading to a stall east of Taiwan. Weakening would probably ensue as Mawar upwells, or churns up, cooler waters from below the sea surface. The Joint Typhoon Warning Center is calling for Mawar to be the equivalent of a minimal Category 1 hurricane several hundred miles east of Taiwan and southeast of Ishigakijima, Japan, by Tuesday.

Thereafter, some weather models depict Mawar drifting west and bringing heavy rain to Taiwan, although the likelihood of this scenario remains low.

Of note is the potential for Mawar to remain stronger for longer than currently predicted. Ocean water temperatures are in the mid-80s, and there’s an absence of disruptive high-altitude winds. In other words, there aren’t many limiting factors working against Mawar. It bears close watching.