Re: Cat 3 to Tropical Storm in 12 hours
Posted by Chris in Tampa on 8/25/2018, 12:44 am
The rain was always likely to be the biggest threat. Like a Hurricane Harvey situation. And the storm isn't over yet.

The wind was always a question mark. Rain was not, expect specifically what islands would get it worse.

There could still be some high gusts at higher elevations over islands that have not been impacted as much so far. The current gusts are 100mph, which would mean even higher at higher elevations. The deep convection is moving toward the islands while the LLC is traveling in a different direction. What matters is what the islands experience. I don't know what the winds are there.

Radar:
https://www.wunderground.com/radar/radblast.asp?ID=hmo&type=N0R&num=10&delay=50&showlabels=1&showstorms=1&lightning=1

Satellite:
http://www.ssd.noaa.gov/PS/TROP/floaters/14E/14E_floater.html

Some parts of Hawaii are very vulnerable to flash flooding. And that did occur. I don't know what some might have been highlighting as to the dangers, but this was a dangerous storm that was going to very likely have significant impacts. It did, from rain. This storm's most certain impact was going to be potentially catastrophic rainfall in some areas. I don't know the full extent of the damage from rain. As for wind, it was always uncertain at what point shear would finally knock it down, allowing it to be steered more by lower level winds to the west. With that uncertainty, along with unique features like the impacts of the islands themselves on steering and track, a threat from the wind had to be taken seriously. Especially since there are higher elevations. Gusty winds and a lot of rain can easily bring down a lot of trees in an area where trees are not often taken out by wind. Also adds debris in what then become raging rivers.

It's not like Florida. Homes are not built as well. More trees can come down. And most people have less experience about what to do about hurricanes.

I didn't happen to notice how much hype there was about the storm. Maybe some put too much emphasis on the wind rather than the rain. But there was too much of a chance it could make landfall, or come close, and if it did as some of the models sometimes showed, it could have been a hurricane since upper level steering was more likely to steer a stronger storm close to the islands.

I think the forecast track was done pretty well. Intensity is always a big uncertainty and obviously Lane got stronger than expected before Hawaii. But they did think it was more likely to stay further from the islands than some of the models, so they seemed to do good on that part.

But again, rain isn't over and some gusty winds could still occur. Some islands likely haven't experienced the worst yet, whatever that might happen to be.



From 11pm EDT Friday / 5pm HST discussion:

"KEY MESSAGES:

1.  Rainbands around the northern and eastern periphery of Lane can
still bring persistent, flooding rainfall and damaging winds.
Effects from tropical storms can and do extend well from the center.
Winds will be accelerated over higher terrain, through gaps, and
where winds blow downslope. Winds will also be stronger at the
upper floors of high rise buildings."

And from advisory:

"HAZARDS AFFECTING LAND
----------------------
WIND: Tropical storm conditions are still expected in and near
rain bands that will affect Oahu, Maui County, and the Big Island
tonight into Saturday. Tropical storm conditions are possible on
Kauai starting Saturday.

RAINFALL: Excessive rainfall remains possible into the weekend,
which could lead to additional flash flooding and landslides.
Lane is expected to produce total rain accumulations of 10 to 20
inches in some areas. Localized storm total amounts up to 40 inches
are possible, mainly on the windward side of the Big Island where
over 30 inches of rain has already fallen in some areas.

SURF: Large swells generated by Lane will impact the Hawaiian
Islands into the weekend. These swells will produce high surf along
exposed south and east shorelines through Saturday."
29
In this thread:
Advisory #40A - Wind History - tvsteve, 8/24/2018, 4:19 pm
< Return to the front page of the: message board | monthly archive this page is in
Post A Reply
This thread has been archived and can no longer receive replies.