The Washington PostDemocracy Dies in Darkness

Historic and horrendous Hurricane Michael by the numbers

October 12, 2018 at 12:05 p.m. EDT
'The whole town is gone:' Hurricane Michael wipes out Florida coastal community (Video: Alice Li, Jorge Ribas/The Washington Post)

The National Hurricane Center issued its final advisory on Michael on Friday morning as remnants of the once-mighty hurricane head toward the North Atlantic. As Michael blew out to sea, it left an indelible mark.

Hurricane Michael enters the books as the fourth-strongest (based on wind, third-strongest based on pressure) hurricane to make landfall in the United States in modern recorded history. It was the worst storm on record for the Florida Panhandle, one of the worst ever in Georgia and Alabama, and continued to deliver a heavy blow as it charged across the Mid-Atlantic.

Hurricane Michael aftermath: Death toll spikes after five storm-related fatalities reported in Virginia

There are many numbers that will be remembered with Michael, and the act of compiling them has only just begun. Below, a list of the some that are among the most telling in the early aftermath of this beastly storm.

73 hours: That’s the time from when Michael was named as a tropical storm with 40 mph winds until it made landfall as one of the most powerful hurricanes in U.S. history. Initially, many expected a landfall along the lines of usual in October in the northern Gulf of Mexico, something like a Category 1 or 2. Michael had different plans.

2 mph: That’s how far Michael was from Category 5 at landfall. Highly unusual, especially in the northeastern Gulf of Mexico. As Capital Weather Gang’s Phil Klotzbach wrote Thursday, Hurricane Michael enters the books as the fourth-strongest hurricane to make landfall in the United States based on wind speeds. Only three infamous Category 5s — Labor Day (1935), Camille (1969) and Andrew (1992) — rank higher.

919 millibars: If being the fourth-strongest hurricane at landfall for winds isn’t enough, Michael attained an even higher status for central pressure: 919 millibars at landfall is the third-most intense on record, behind only Labor Day and Camille. Ear popping.

10-plus feet: Mexico Beach, to the east of Panama City on the Florida Panhandle, was more or less Ground Zero for Michael. In the “right front quadrant” of the eyewall, the strongest part of the storm, the area was decimated by wind and water. The storm surge rose to at least 10 feet here, high enough to wash entire homes and buildings away.

129 mph: That’s the highest verified gust (so far) from Michael. That may seem low for a 155 mph hurricane, but keep in mind that the observation network is not very dense and the worst winds of a hurricane are often fairly localized and over water or right on the shore.

While Panama City, where this wind speed was clocked, was in the eyewall, it was also on the weaker backside, so it is unlikely the strongest winds were there. The instrumentation also failed at 129 mph, as did other sensors in the storm’s path. Looking for more verification of the high winds? Weak winds don’t mow down forests.

55 millibars: Michael’s pressure was insanely low. When it made landfall, it set low pressure records in that area and over considerable distances inland. Panama City recorded a pressure of 922.4 millibars near the time of landfall. That was 55 millibars lower the old record there, set during Hurricane Kate in 1985. David Roth of the Weather Prediction Center keeps pressure records for the country. This one is changing his maps.

3: Michael was Category 3 in Georgia. That made it the strongest storm in the state since 1898, even though it did not make landfall there. Hurricane force winds tend to mostly hit areas right near the coast. Not with Michael.

9.62 inches: This is the highest precipitation total on the Weather Prediction Center summary for Michael, from the Black Mountain area of North Carolina, not too far from Asheville in the western part of the state.

The Mid-Atlantic posted the highest rainfall totals for the storm as it interacted with a strong cold front that helped squeeze more moisture out of the air. Here are the heaviest amounts, by state: Bowling Green, Va., at 8.04 inches; Jefferson, S.C., with 7.39 inches and even Salisbury, Md., with 7.10 inches. In addition to the quick-hitting and torrential rain, the storm brought wind gusts of up to 60-75 mph in the Mid-Atlantic.

Two million: Roughly two million customers lost power in Michael. Virginia leads the list with over half a million losing power in that state alone. Interestingly enough, the tally is rather close to the forecast estimate before landfall from the University of Michigan. Additionally, at least 325,000 folks were told to evacuate in the lead-up to the storm. Michael has so far left at least 11 dead, many more injured and thousands of homes and businesses destroyed. All of those life and property numbers are preliminary and, unfortunately, are very likely to rise.

Less than 10 miles: The National Hurricane Center’s average 72-hour error for the position of a hurricane is about 100 nautical miles (~115 miles), which has gotten smaller and smaller over time. For Michael, the forecast was off by less than 10 miles.

The storm was also predicted to be a much weaker animal at that point in the forecast, as it was still a tropical depression, but intensity forecast is still a tricky challenge. With that in mind, the forecasts for its intensity quickly ramped up in subsequent predictions, and there’s little doubt the spot-on forecasts saved countless lives yet again.