WEST MICHIGAN — Last week it was Harvey that absolutely inundated southeast Texas with up to 52 inches of rainfall in some spots leaving places like Houston, Beaumont, and Port Arthur literally under water. This week another tropical system is in the mix. Hurricane Irma is massive in size, scope, pressure, and wind! It’s currently battering the U.S. and British Virgin Island in the tropical Atlantic. It’s expected to track over the northern shores of Puerto Rico, Hispaniola, and Cuba.
There are five categories for hurricanes based on wind speed and the damage it can do. One is the least, five is the worst. Category five produces winds of 157 mph (sustained) or higher. Irma the past two days has been sitting around 185 mph winds with gusts to 225 mph. To put this in perspective, that would be equivalent to an EF-4 tornado!
Irma is one of the more powerful Atlantic basin storms ever. Generally speaking, the lower the pressure with these systems, the stronger the storm…although the two don’t always correspond. Wilma in 2005 and Gilbert in 1988 both had 185 mph, but they had lower central pressure at it’s core than Irma currently does.
Irma is massive and a monster storm. Including the outer bands, the system is at least 500 miles across with an eye about 25 miles wide. Many times…the eye of a hurricane can have calm, sunny conditions with high cirrus clouds, and is usually very visible on both satellite and radar imagery. Such is the case with Irma!
For comparison purposes only, the National weather Service in Gaylord decided to overlay Irma’s satellite image over Michigan to give Michiganders perspective in size. It goes without saying that Michigan cannot, nor will it ever see a hurricane. We can feel some of its remnants and impacts, but hurricanes are warm-core tropical systems that require large oceans or warm water to get their strength and development.
The image below shows Irma superimposed over Michigan and its outer bands stretching from Buffalo, New York to central Wisconsin. At least 500 to 600 miles across.
The next image below shows how huge the eye of the system is (about 25 miles across) and would cover most of the Mackinac Island and the extreme top portion of northern lower Michigan.
I should also note that while I may have compared wind speeds between a hurricane and tornado, hurricanes affect a much larger area than do tornadoes. They also carry deadly force from rushing water that floods and drowns from things like storm surge…the push or wall of water the system creates as it arrives on shore, and the inches and inches (or in some case like Harvey…feet) of rain they produce.
The latest track of Irma is expected to take it around/near southern Florida, or up the East Coast of the Florida and the United States. See below.
The path of hurricanes are determined by our upper level steering winds. The cold front currently over the East Coast of the United States along with the trough over the Great Lakes and Canadian high pressure building in this weekend may act to “deflect” or move this hurricane farther east. Make sure to stay up on later forecasts. For further perspective, the last category five hurricane to hit the U.S. mainland was Andrew in 1992, which devastated southern Florida. Get our local West Michigan forecast at www.fox17online.com/weather or keep up with the hurricane at the National Hurricane Center.