Wednesday, September 16, 2020

Hurricane Sally Strengthened At Landfall; Flooding Intensifies, Spreads

Hurricane Sally made landfall early this morning right around Gulf Shores, Alabama. Based on early videos from news outlets and social media, there's once again LOTS of damage with this one. 

Inside a home flooded by
Hurricane Sally in Foley,
Alabama this morning.
Photo by Cambri Radford
via Twitter

Following a trend this hurricane season, Sally strengthened some just prior to landfall.  Top sustained winds had been holding near 85 mph during the day Tuesday, but ramped up to 105 mph just before landfall.

Reports from Gulf Shores are that lots of people were calling 911 for help early this morning and authorities just couldn't get to them because of the conditions.  Early reports indicate many people, possibly thousands, are trapped by flooding. I definitely worry about fatalities. 

It's rather unusual for a hurricane to get more intense just before landfall.  More often than not, some land interaction will either weaken a hurricane or at least prevent it from getting stronger.  This is especially true with hurricanes with a very slow forward speed. 

That is certainly true with Sally. It's forward speed was 2 mph most of the day and at landfall.  That's the average forward speed of an 80 year old person walking. 

This year, hurricanes have been worryingly strengthening as they made landfall. In the 24 hours before landfall.

According to hurricane expert Philip Klotzbach, Hurricane Hanna went fro 50 to 90 mph in Texas. Isaias went from 70 to 85 mph on the East Coast.  Laura went from 105 to 150 mph in southwest Louisiana. Nana went from 60 to 75 mph in Belize. Paulette went from 75 to 90  mph in Bermuda, and Sally went from 85 to 105 mph in Alabama. 

Plus we remember Hurricane Michael rapidly intensifying to a Category 5 storm in the Florida panhandle as it made landfall in 2018, with disastrous results. 

I'm not sure why we've had this trend in recent year. I'm sure we'll learn more from the scientists soon. 

For what it's worth, one of the United States' top meteorology experts Marshall Shepherd tweeted this morning:

"I want to underscore that rapid intensification of hurricanes along coasts may be a new reality in this climate-warmed era, so rather than be surprised or outraged, I think people have to adjust to ew normal. Just because you lived through 'so and so' may not cut it anymore."

Sally, of course, isn't nearly done. As advertised, Sally is dumping incredible amounts of rain.  Its slow forward motion means the rain can dump for a longer period of time than usual in a hurricane. Reports from near Pensacola, Florida indicate two feet of rain already and torrential downpours continue. To nobody's surprise, flooding is way, way severe and getting worse.

Downtown Pensacola was inundated this morning due to a combination of storm surge and the torrential rains. 

Hurricane Sally onshore this morning
in northwest Florida

More than 30 inches of rain seems likely to accumulate in the path of the storm. 

Sally's winds will rapidly diminish today, but the torrential rains will continue on as the storm crawls northeastward into the Carolinas.  Extensive flooding will hit Georgia and the Carolinas in the next couple of days. 

For those of you who are wondering, Sally will have absolutely no effects on the weather here in Vermont. 

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