Comprehensive Update on Tropical Storm Helene; Update 11pm

NHC is now forecasting sustained winds of 120 mph at landfall which would be a strong Cat 3 hurricane. People in Tallahassee should prepare for hurricane force winds. 

Next update will be tomorrow morning. 

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The newest satellite image (6:54pm) shows Helene developing rapidly. This lends credibility to the forecasts and I urge you to follow the safety recommendations. 

----- 5:15pm update below ----

Hurricane Helene is forecast to come into the Florida Panhandle late Thursday with high winds and a major storm surge ahead of the center. Here is a complete update on the storm. Please forward this information to your friends and relatives. 

Hurricane Warnings have been issued for parts of the Gulf Coast of Florida. The central pressure has dropped to 995 millibars (as of 6pm) 992 990 millibars at 8pm and the maximum sustained winds are 50 60 mph. There are also hurricane warnings for Cancun and the northeast Yucatan.

The Forecast Path of the Eye of Helene

Here is an explanation of the map. 

• M = major hurricane with sustained winds to 115 mph at landfall
• H = hurricane.
• S = tropical storm. 
• Red = hurricane warning
• Blue = tropical storm warnings
• Pink = hurricane watch
• Yellow = tropical storm watch 
• Amber = area of tropical storm force winds (40 to 50 mph, at this time)

Please note the hurricane warnings extend to the Georgia border with the hurricane watch extending about 30 miles into southern Georgia. The hurricane watch extends south to Tampa and vicinity. Here is the ECMWF model forecast of peak gusts. Note that winds are forecast to be strong enough to topple trees and cause power failures well into Georgia. 

What would I do now if I lived in a coastal area with this storm potential? 

• Make sure infirm relatives and friends will be cared for. 
• Refill prescriptions. 
• Purchase any essentials.
• Fully fuel your auto and/or chain saw. 
• Make sure your "go kit" is up-to-date and ready. There will likely be evacuations in coastal areas of the Panhandle, in Tampa Bay and most of the area of the Florida Big Bend!
• If you live in a mobile home, make plans to shelter elsewhere if the storm reaches hurricane strength. 
• There will be power failures that, in many cases, will last for days. Prepare accordingly.

Life-Threatening Storm Surge! 

From the Tampa Metro to Indian Point, this will be a major storm surge with life-threatening consequences. If you are told to evacuate, please do so. 

A great graphic regarding storm surge. 

Flood Threat For People Inland in the Southeast

There is a major flood threat from Helene. Not only are more than 13" of rains expected in the southern mountains, the Atlanta Metro is forecast to have ~7.5 inches! If you live in a flood-prone area, make plans to evacuate now!

There is a Tornado Risk, Especially Thursday

The area on yellow will have an enhanced risk of tornadoes Thursday and Thursday evening with a significant risk in the green area.

For Meteorologists 

Compare these two satellite images. The upper image is from 12:20pm. The arrow points to the then-center of Helene. 

Now, look at the images fro 4:20pm. 

Clouds have rapidly filled-in around the center and, perhaps, even more important, there are now a few lightning bolts in that area. They are a sign of a strengthening tropical storm or (later) hurricane. Helene is finally getting its act together. 

My impression from the models is that this storm will continue intensify until about the time it makes landfall in the Florida Panhandle. Do not even think about chasing Helene until you have read this piece by Chris Collura at the top of the page!