Powerful Hurricane Irma passed directly over Barbuda last night with estimated 185 mph winds. This morning, it is directly over Saint-Martin and Anguilla.
The pressure trace on the island of Barbuda shows how quickly pressure can drop with such an intense storm as Irma. The lowest pressure was estimated around 914 mb. Mb stands for millibars, a common unit of pressure in meteorology. Inches of Mercury (InMg) is more commonly reported and 914 mb converts to 26.99 InMg. A typical value in the Ozarks is about three inches higher!
A wind sensor also showed a gust to 154 mph before it stopped working.
Irma is moving almost due west. It is expected to make more of a WNW move later today. This is very important because the path and intensity will in part be dictated by its proximity to Puerto Rico. Generally, hurricanes will weaken a bit when introduced to land.
Of course, the future track with regard to Florida and the U.S. is dependent in part on getting the forward motion right today. Also, you may see the latest guidance from late last night/ overnight with a shift east in the track and a sharp turn north. With so many people in the potential path and considering the power of Irma, no one is going to disagree with model guidance at this point. I however am somewhat dubious of the accuracy and I suspect a wide variety of outcomes is still possible.
— Ryan Maue (@RyanMaue) September 6, 2017
— NWS Twin Cities (@NWSTwinCities) September 6, 2017