Tag Archives: Equatorial Africa

Cyclogenesis, Featured, Hazards, Hurricanes, Tropical Cyclones, Tropical Depression, Tropical Storm, Tropical Wave, Weather

Dangerous Hurricane IRMA is heading toward our neck-of-the-woods!

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Infrared GOES satellite view of 27 August 2017 showing Harvey over Texas, and a few tropical waves and other potential future tropical cyclones over the northern Atlantic basin. One of these tropical waves in particular, the one just emerging over the east Atlantic in this image, was the actual ‘seed’ that generated Hurricane IRMA.

Eight days ago, on 27 August 2017,  just as we watched the catastrophe of Hurricane HARVEY unfolding in Texas, a strong tropical wave originally formed near the head of the Nile River in eastern Africa fed by moisture from the Indian Ocean, emerged over the waters of the East Atlantic south of the Cape Verde Islands already exhibiting cyclonic tendencies. At the time I submitted this particular system warranted our attention and close monitoring by all hurricane-vulnerable interests around the Atlantic basin.

Infrared GOES EAST satellite image (NOAA) of Monday 4 September 2017 showing a strengthening Hurricane IRMA over the central Atlantic, as well as tropical waves chasing it for the east , and another potentially cyclonic disturbance in the Bay of Campeche in the southwestern Gulf of Mexico.

As of today Monday 4 September 2017, LABOR DAY!, after having traveled more than 9,000 km this system is major Hurricane IRMA over the Central Atlantic moving toward the Lesser Antilles and possibly the USA coastal region.

Visible light satellite image (Courtesy of NASA) of 4 September 2017 showing major Hurricane IRMA, as a well organized, symmetrical, compact tropical cyclone, with a clearly defined eye as it moves toward the Lesser Antilles and Puerto Rico.

Major Hurricane IRMA looks quiet organized this morning of Monday 4 September 2017, LABOR DAY!, with a distinct central eye, a round and symmetric shape, and dense bands of rain and thunderstorms.

Projected five-day track for Hurricane IRMA issues by the National Hurricane Center during its 0500 advisory on Monday 4 September 2017

The forecast track by the National Hurricane Center (NHC) has shifted somewhat southward for the next 3 – 5 days bringing it closer to the Antilles. Florida remains within the ‘cone of uncertainty’ this far out, so this is the time to review your emergency plans. Regarding IRMA’s projected track over coming days it is important to note that there are other tracks developed by various agencies, which vary from that posted by the NHC. For example, the track projected by the U.S. Naval Research Laboratory shows a more northerly route than that of the NHC, which shifts the cone of uncertainty more toward mainland Florida and our neck-of-the-woods here in southeastern Florida. This discrepancies between projected tracks illustrate the difficulty in predicting where a hurricane may actually go, and the fact that  the longer the forecast goes into the future in term of how many days it covers the larger the uncertainty is.

Projected five-day track for Hurricane IRMA developed by the U.S. Naval Research Laboratory as of 4 September 2017. Notice the slight differences with the track from the NHC posted above.

The important thing is to be aware that hurricane forecasting is not an exact science, and despite all the satellite tools, hurricane hunter data provided by airplanes flying into and around the storm, and the years of experience and expertise of forecasters at the NHC,  it is just not possible to exactly predict where a hurricane will make landfall. Consequently the best approach for those residing in vulnerable communities is to monitor the advisories regularly and closely, and to pay attention to instructions from local emergency management officials.

So, get ready. Be prepared. MITIGATE! Also, keep an eye on the strong tropical waves chasing after IRMA over the Eastern Atlantic off the coast of Africa and inland over Equatorial Africa. The entire system is loaded with ‘seeds’ for potential cyclonic activity.

Cyclogenesis, Featured, Flooding, Hurricanes, Tropical Cyclones, Tropical Depression, Tropical Storm, Tropical Wave, Weather

In the aftermath of Harvey the tropical north Atlantic is agitated!

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A bit more than two weeks ago one more tropical wave emerged from equatorial Africa over the waters of the eastern Atlantic, south of the Cape Verde Islands. By August 18th if was morphing into a tropical storm over the eastern Caribbean aiming for the area of Belize and the Yucatan Peninsula of Mexico, Eventually it made landfall and traversed the Yucatan to then emerge over the Bay of Campeche in the southwestern Gulf of Mexico where it reorganized, gained strength and became Hurricane HARVEY!

While we were commemorating the 25th anniversary of Cat 5 Hurricane ANDREW (1992), and remembering all the devastation and lessons learned, HARVEY continued to strengthen as it approached the Texas coastline and a vast region of very warm surface waters in the northern Gulf. We all know what happened next, Harvey intensified rapidly near the coast reaching category 4 strength as it made its second landfall. We all know the rest of the story, in fact we are all watching the story develop as Harvey is pouring a veritable deluge, one for the record books, over a vast region of Texas.

Keeping an eye of Harvey should not detract us from also looking at the rest of the Atlantic basin, which is quite agitated on this Sunday 27 August 2017. The tropical wave that was in the eastern Gulf near Florida, has caused abundant rain over central and southern Florida while traversing the state and emerging over the Atlantic where it is now off the coast of Georgia and South Carolina, getting organized and looking poised for possible cyclonic development.

Infrared GOES satellite view of 27 August 2017 showing Harvey over Texas, and a few tropical waves and other potential future tropical cyclones over the northern Atlantic basin

Beyond this potential new threat of cyclonic impact to our coastline, we see yet another tropical wave over the eastern Gulf, and a few more from the neighborhood of Puerto Rico to the eastern Atlantic near the Cape Verde Islands. In fact that still far away tropical wave off the African coast is already showing some cyclonic tendencies that warrant close monitoring in coming days.

So, the entire Atlantic basin appears agitated and populated by ‘seeds’ for potential cyclogenesis in coming days, just as we approach what historically has been the peak of the annual Atlantic hurricane season. Food for thought. All interest in the Caribbean, Gulf, Florida and the Atlantic seaboard of the U.S. must remain alert. Be prepared. MITIGATE!