REUTERS/Carlo Allegri
A truck drives along a road that has been washed out as Hurricane Michael comes ashore in Alligator Point, Florida, U.S., October 10, 2018.
- Hurricane Michael is on track to be the strongest hurricane to hit the US in 50 years, and the third strongest ever.
- That's according to measurements of the storm's central pressure, which is a key indicator of the intensity of a storm.
- Michael's pressure was 919 millibars as of 1:00 p.m. ET, making it more powerful than Hurricanes Katrina or Andrew.
- The storm's wind speed puts it close to being a Category 5 hurricane.
Hurricane Michael has picked up steam as it sped across the Gulf of Mexico towards the Florida Panhandle. As of Wednesday at 1:00 p.m. ET, the storm had sustained winds of 150 mph, according to the National Hurricane Center, making it a major, Category 4 hurricane.
When Michael makes landfall on the Florida Gulf Coast this afternoon, it'll almost certainly be the strongest storm to ever hit the region.
Michael is also on track to be the third strongest hurricane to ever hit the US, and the strongest in 50 years.
Michael's minimum central pressure - a key measure of hurricane strength - was measured at 919 millibars at 1:00 p.m. ET. Lower central pressure indicates a stronger storm, so this one is extremely powerful. That measurement indicates Michael is more intense than Hurricane Andrew, which hit Florida in 1992, with a pressure of 922 mb. Katrina, which devastated New Orleans in 2005, had a pressure of 920 mb.
Central pressure is the measure of how much the atmosphere in the middle of a storm weighs. Normal air pressure is about 1010 mb; when central pressure is significantly lower than that, things become more turbulent, with more air movement and wind kicking up.
Central pressure is actually a better measure of the damage that hurricane will cause than wind speed, according to a study published in the journal Nature Communications in 2017, though wind is the basis for hurricane categories.
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But Michael is a monster storm by wind speed as well. The sustained 150 mph winds make it not far from a Category 5 storm - the cut off between Category 4 and 5 is wind speeds to 156 mph. There's only been one storm with higher sustained wind speeds this far north in the Gulf of Mexico before: Hurricane Camille in 1969.
No matter where the storm ends up falling in the record books, the key message for people in the storm's path remains the same. As the Tallahassee office of the National Weather Service said on Twitter, "If you're not sheltered in place now, you need to be!"