Saturday, September 09, 2017

Hurricanes Irma and Jose: September 9, Update B

How y’all doin’? A middle-of-the-day-ish (here) check in for you…

Hurricane Irma
She is still officially a cat 3 storm with winds of 125mph, central pressure 938mb (cat 3 range: 111-129mph). The infrared satellite - showing where the strongest rain and thunderstorms are (the red and dark orange are very strong - tornadoes etc). 
The visible satellite image, best for really seeing the status of her eye (in daylight) - clear or murky?: 
The water vapour satellite image - shows where the most water vapour is in the storm - just pretty to look at really :-): 
She is now officially on a WNW track again still at 9mph, and is at 23.3N, 80.4W (although she look a little like she's on a NW track to me, but that could just be a wiggle). Her core is just about leaving Cuba and the eye is a little more visible (although still quite murky), which still suggests a strong cat 2/weak cat 3. Now we wait and see how much she will re-intensify as she transits across the Florida Straits and picks up some more water vapour – she is looking a bit better compared to a few hours ago.

Not a huge change in the track guidance:
My thinking from the previous post still stands on what is coming up next. If you look at the bigger picture, you can see that she has finally met that front which you can see from the long line of clouds streaming off to the northeast:
By the way, Florida has been having a little stormy weather over the past few days from that front – the storm bands from Irma first started to reach the southern tip of Florida yesterday. The first bands are just reaching Tampa Bay around now.  

To look at storm surge, go to NOAA's Tidesonline: https://tidesonline.nos.noaa.gov/geographic.html, click on Florida and pick the station you want to look at. The winds in a storm are counter clockwise, so for the west Florida: whilst she is south of you the levels will be below normal but when she moves north of you, the water levels will rise as water is pushed on-shore. The east coast of Florida will experience the reverse: when she is south of you, water levels will be above normal but when she moves north of you, water levels will drop – this includes the Keys. The levels are already around 1ft above normal along the Keys:
<Technical Alert!> The top graph shows the water level. In this graph, the red line is the actual observed sea level, the blue line is what the predicted water level would be because of the tides, and the green line is the difference between the two. The height of the green line gives you the storm surge level (~1 ft at the moment). The graph below that is wind speed (still increasing in Key West – around 30mph, so not quite Tropical Storm force yet) and direction. Below that is air pressure (which you can see is still dropping), and below that is air and sea surface temperature. Wind speed is still less than 15 knots (about 17mph) (1knot = 1.15 mph) so we don’t have Tropical Storm force winds up here yet. <End Technical Alert!>

Her eye is now on the Key West Radar:
To monitor winds, you can also go to the airports and look at their wind sensor readings. From Key West airport for example, wind speed is still around 30mph at the airport too – so not quite yet Tropical Storm force:

More later! 

Hurricane Jose
No change here so a proper update later.

Stay safe everyone!
J.  

Blogs archived at http://jyotikastorms.blogspot.com/
Twitter @JyovianStorm
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DISCLAIMER: These remarks are just what I think/see regarding tropical storms - not the opinion of any organization I represent. If you are making an evacuation decision, please heed your local emergency management and the National Hurricane Center's official forecast and the National Weather Service announcements. This is not an official forecast. If I "run away, run away" (Monty Python), I'll let you know. 

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