Cyclone Nilofar targeting India's Gujarat State, Southern Pakistan

After becoming impressively strong on Tuesday, Cyclone Nilofar has begun to weaken. Nilofar is expected to head towards southeastern Pakistan and northwestern India, with landfall likely on Saturday.

On Tuesday afternoon, Nilofar intensified to the equivalent of a hurricane with estimated wind speeds of 130 mph, according to the U.S. Joint Typhoon Warning Center, about 650 miles south-southwest of Karachi, Pakistan. Nilofar underwent rapid intensification, and became the third strongest tropical cyclone of record in the Arabian Sea.

Only Gonu in 2007 (Cat. 5; 165 mph winds) and Phet in 2010 (Cat. 4; 145 mph winds) were stronger Arabian Sea tropical cyclones in the historical record, according to Masters.

By Wednesday afternoon (local time), winds have weakened to the equivalent of a Category 3 hurricane, with wind speeds of 115 mph. Incidentally, the term "hurricane" is not used in this case.

Nilofar is now tracking toward the north under the steering influence of an upper-level high pressure system centered over southern India.

By later Wednesday (local time), Nilofar will curl sharply northeast and accelerate, as upper-level jet stream winds grab hold of the cyclone. On this track, Nilofar will remain well east of the Arabian Peninsula.

These jet stream winds will impart increasing vertical wind shear, and drier air may also work into the cyclone. Both of these factors are expected to weaken Nilofar significantly by the time it makes landfall somewhere along the coast of India's Gujarat state or extreme southeast Pakistan Saturday, local time. At the time of landfall, Nilofar is expected to be the strength of a low-grade tropical storm, if not weaker.

The (IMD) -- the agency responsible for tropical cyclone advisories in the northern Indian Ocean, including the Arabian Sea -- has issued a yellow message cyclone alert for the northern coast of India's Gujarat state.

The IMD warned of "damage to thatched roofs and huts" near the landfall location of Nilofar Saturday and urged fishermen along and off the Gujarat coast to return to port. Coastal hut dwellers were urged to move to safer location.

The warned of isolated heavy rainfall and strong, gusty winds in the Lower Sindh including Karachi, and coastal areas of Balochistan from Wednesday night into Saturday morning.

Karachi, one of the world's most populous megacities (2014 population estimate: 23.5 million), only averages about 7.9 inches of rain each year. Depending on the track of Nilofar, over one inch of total rainfall is possible, which could trigger flash flooding.

The image below of global tropical cyclone tracks indicates that Arabian Sea tropical cyclones are not as unusual as they sound.

Each year, an average of 1-2 tropical cyclones form in the Arabian Sea, according to .

These cyclones are most likely to form in two periods: from May - June and October - November. The mid-late summer period is typically not favorable, thanks to increased wind shear from the wet phase of the Asian monsoon.

In June 2007, , making landfall in Oman, then in southern Iran.

Gonu claimed 100 lives in Oman, Iran and the United Arab Emirates and was responsible for $4 billion in damage, according to .

Almost exactly three years later, Cyclone Phet alarmingly intensified to a equivalent cyclone, before weakening to a Category 1 storm upon making landfall on the eastern tip of Oman, east of the capital city of Muscat.

In May 1999, Cyclone ARB 01 slammed into Pakistan near Karachi as a strong equivalent storm, killing at least 700 in Pakistan. This was the strongest tropical cyclone on record to hit Pakistan.

In the limited historical record, however, strong cyclones in the Arabian Sea are more rare than other basins, due to the proximity of dry air from the Arabian Desert, the aforementioned increased wind shear during the wet phase of the Asian monsoon, and the basin's overall small size.