DISCUSSION: During the course of the past 3 to 4 days, a good portion of the global atmospheric science community had been “ranting and raving” over the evolution of Tropical Cyclone Mekunu. Through considering the historical and scientific context of this tropical cyclone, it is relatively easy to understand how and why so many people around the world or as interested as they were in this powerful and somewhat rare event. Tropical Cyclone Mekunu was particularly interesting since it formed during the month of May within the northern to northwestern portion of the Arabian Sea. It is also worth noting that Tropical Cyclone Mekunu also (within the span of approximately 24 to 36 hours) strengthened from the equivalent of a Category 1 hurricane (i.e., maximum sustained wind speeds of at least 33 meters per second or 74 miles per hour) to the equivalent of a Category 3 hurricane (i.e., maximum sustained wind speeds of at least 49.6 meters per second or 111 miles per hour). Thus, it goes without saying that this storm underwent a period of what can only be categorized as somewhat rapid intensification.
This period of somewhat rapid intensification for Tropical Cyclone Mekunu is relatively unique because it formed and developed in an ocean basin which (although it is relatively warm) often provides a substantial amount of wind shear due to the nearby ambient effects on monsoonal convection. Having said that, this storm persevered and intensified into a substantial tropical cyclone which went on to deliver a plethora of rainfall to a region which is predominantly dry for most of a typical calendar year. Hence, this tropical cyclone single-handedly generated major regional flooding and flash flooding episodes.
As can be seen in the animated infrared satellite imagery attached above, you can see how the storm’s structure generally was maintained both prior to and during the period of landfall. However, what you cannot see but remained to be the case, was that Tropical Cyclone Mekunu went on to also maintain most of the core structure even several hours after landfall. This was likely due in part to the fact that as the core of Mekunu moved onshore, the combination of intense diurnal heat over the southern Middle East along with continue fluxing of warm, moist air off the northwestern Arabian Sea. This combination of factors may have allowed Mekunu to hold on to some of its peak winds for a bit longer than expected in the first few hours after initial landfall.
Also, note in the upper-most image, how you can see floodwaters captured as they rushed through parts of the city of Hadibu on the Yemen island of Socotra. This case study goes to show that even in other less typical parts of the world for intense tropical cyclone development, there are still situations where unexpected and unanticipated things do sometimes unfold.
To learn more about this Middle East tropical cyclone story, click on the following link: https://globalnews.ca/news/4233899/cyclone-lashes-oman-and-yemen-fatal/ .
To learn more about other high-impact weather events occurring across the Indian Ocean and Asia, be sure to click here!
© 2018 Meteorologist Jordan Rabinowitz