The Peak of Hurricane Season Has Arrived

Today, September 10th, marks the climatological peak of hurricane season. The waters are nice and warm with lots of tropical waves traveling off the coast of Africa. It is this time of year that people tend to think of when they hear the word “hurricane,” with the African Easterly Waves developing into classic Cape Verde-type hurricanes. It is not surprising that during the peak of hurricane season we have 2 named storms (Tropical Storm Leslie and Hurricane Michael) with a third system likely to form soon. In case you were wondering, it would be called Nadine if it reaches tropical storm strength.

With that in mind, let’s look at the season so far. We have had 13 named storms, 7 hurricanes, and 1 major hurricane. We had an early start to the season with 2 named storms before the official June 1st start. Tropical Storm Beryl, who made landfall in Jacksonville Beach, Florida made history as the strongest May storm on record with maximum sustained wind speeds of 70 mph (just below the 74 mph hurricane cut off) before landfall. A few weeks later there was Tropical Storm Debby who dumped large amounts of rain across Florida, especially on the west coast. Miami hasn’t been directly effected yet, but did get rainbands and weak tropical storm force winds as then Tropical Storm Isaac passed just below the Keys. Hurricane Isaac later went on to strengthen in the Gulf of Mexico and sat on top of Louisana, unleashing rain and winds for what seemed like forever. The major impact with Isaac was the flooding, as natural levees were topped and the Mississippi River overflowed into the surrounding areas. Ironically, this occurred around the 7th anniversary of Hurricane Katrina, and although New Orleans was fine this time, others were not so lucky. The first major hurricane was Hurricane Michael in the Atlantic which was a Category 3 for 6 hours.

Rain and flooding have been the main story so far this season, but there is still the second half to go. Let’s see what the rest of the season has to bring, and keep our fingers crossed. Hurricane season officially ends on November 30th.

Angela Colbert
Meteorology & Physical Oceanography
Graduate Student
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How Do Hurricanes Get Their Names?

Isaac, Kirk, and Lesile, oh my! As hurricane season is ramping up to its peak, all those storms swirling around in the Atlantic can get confusing. To help stop this confusion, we name tropical storms and hurricanes to more easily and clearly communicate information about them (we use numbers for tropical depressions). However, this was not always the case.

Back in the day, hurricanes were referred to by their position (latitude-longitude) or in some cultures, named after saints. This was not only hard to communicate, but confusing to the public about warnings. Thus after World War II, the navy began flying into the storms and referred to them by the international phonetic alphabet (Able, Baker, Charlie, Dog…and my personal favorite, Love) from 1950-1952. In 1953, it was decided that the storms would be named by women’s names. This was a common military practice when speaking about ships and planes, so it was carried on. The storm naming responsibility landed in the hands of the National Hurricane Center until 1977, when they relinquished naming rights to a regional naming committee with the World Meteorological Organization.

It wasn’t until 1979 that the current naming procedure was put into place. The committee decided to have 6 revolving lists of names that would repeat. These names include both male and female names that alternate and that are common in English, Spanish, or French speaking cultures. This means that the current list of storm names for the 2012 season will be repeated in 2018. The names are in alphabetic order with the “A” name used for the first storm of that year, even if it forms before the official start of hurricane season on June 1st or if the previous season did not use all the names on the list. The storm alphabet excludes the letters Q, U, X, Y, Z (how many names can you think of with those letters?). In the uniquely hyperactive seasons (let’s say 2005) when all the names in the storm alphabet are used, names are given following the Greek alphabet (Alpha, Beta, Gamma…).

The only exception for these names is when a storm has a significant enough impact that it would be inappropriate to continue using the name. That name is then retired. Some notable retired names are Andrew (1992) and Katrina (2005). When this happens, the committee meets to discuss and replace the name on the list.

My guess is that there will be no Isaac in 2018, so we will have a new “I” name to enter the list rotation. Any guesses on what the new name will be? Leave your guess in the comments.

Angela Colbert
Meteorology & Physical Oceanography
Graduate Student
Follow the Rosenstiel School on Twitter: @UMiamiRSMAS
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Quick Look: Hurricane Isaac vs Hurricane Katrina

Much to the relief of everyone in southern Florida, Isaac never did get too organized or intense after passing by Haiti and Cuba. It maintained a steady tropical storm intensity as it skimmed by Key West, as it made the journey across the Gulf of Mexico. It has just been upgraded to a hurricane off the Louisiana coast, but it could have been much, much worse.

During the early morning hours on August 29, 2005, Hurricane Katrina made landfall in eastern Louisiana as an enormous Category 3 storm. It intensified from a tropical storm to a minimal hurricane as it passed over Miami and the southern Florida peninsula on August 25th, then took full advantage of ideal conditions in the eastern Gulf of Mexico and dramatically intensified to a monster Category 5 storm on August 28th. Something similar was certainly possible with Isaac, and haunting similarities were everywhere – the dates, the tracks, the size, the landfall location, but one key difference remained: the intensity.

Hurricane Katrina (2005 – top) vs. Hurricane Isaac (2012 – bottom) at exactly 10:15am on August 28th.

I also made a comparison image of the two storms as they appeared on satellite at exactly the same date and time, just seven years apart (10:15am on August 28th). At this time, Katrina had 165mph sustained winds, while Isaac had 70mph sustained winds.

As far as Isaac goes, it is now a hurricane with 75mph winds as of 11:20am this morning. This is the first time that it has reached hurricane intensity during its entire 12-day journey across the Atlantic. It is just hours from landfall, and just hours from the exact landfall time of Hurricane Katrina seven years ago. You can monitor the storm with a long radar loop from New Orleans. Rainfall totals along the northern Gulf coast are expected to be in the 12-18” range, and the storm surge could be significant between the center of the storm and places for hundreds of miles east of the center as its circulation pushes the ocean out ahead of it and onto the coastline.

Luckily, we aren’t looking at a repeat of one of our country’s largest natural disasters, but it acts to keep us vigilant and prepared.

Brian McNoldy
Senior Research Associate
& Author of Tropical Atlantic Update
Follow Brian on Twitter: @BMcNoldy