"But seeing they could not See; hearing they could not Hear"
“The views expressed herein are those of the author and do not necessarily represent those of the National Weather Service or affiliate/related organizations. Please consult .gov sites for official information”

"From its chamber comes the whirlwind, and cold from the scattering winds." - Job 37:9.

"The wind blows to the south and turns to the north; round and round it goes, ever returning on its course".

Wednesday, October 4, 2017

"Conditional Risk" of Rain / Storm Event Thursday - Early Saturday

Area of Dune Line, Cape Canaveral, Post -IRMA
TODAY: Slowly increasing atmospheric moisture from South to North now in process (see image below). A 'pocket' of moisture (per morning Global Forecast System - GFS model) is crossing Central Florida late morning through early afternoon, producing some quick passing 'brisk showers' along with the already breezy conditions , particularly along the 'immediate beach side'.

These might well be coming to and 'or might not' later in the day. Regardless, the bigger 'potential' news lies ahead in the mid-range  later tonight toward early Thursday as inherit atmospheric moisture associated with an inverted short-wave trough (tropical wave) approaches the Florida East Coast.

Latest visible satellite loop 'appears' to show that perhaps a low pressure area is forming ESE of South Florida in association with this wave.  

That is of importance to realize in the forecast range, for if a low pressure area does manage to form, the risk of heavier rainfall and potentially some land-falling 'stronger storms' (perhaps waterspout potential) will increase. 

The inverted trough extending northward from any 'said low' (if it can form) would  operate as low-level convergence boundary  as the surface reflection passes from east to west across South Florida and the Florida Straits all day Thursday into early Friday in the midst of PWAT Air (Precipitable Water) over 2.0".

Greatest instability will lay across the east coast and near shore waters either way, mainly from Extreme Southern Volusia County southward , a contribution from warm Atlantic waters.

Animation earlier today shows the 'tidal wave' of moisture (per previous blog post) approaching from the east. The leading edge is reaching Brevard County even now, but the greater moisture per most model guidance is not to arrive in this area, and further north as well , until within an hour or so of sunrise Thursday morning.  This loop ends at 10:30AM, Wednesday morning.

This  image (below) is as of 12:30PM, EDT. The  'Deeper Moisture' is still off to the east and south of Central Florida and even Southeast Florida. In the below image one can see the focal area of red which is near where it appears per surface visible satellite animation that a surface low might be forming over eastern portions of the Florida Straits north of the coast of Cuba.

Given a number of 'significant uncertainties'...this  post will punctuate perhaps what might be a 'worst case' scenario . 

A phrase oft heard during the time of IRMA was, "Prepare for the worst, hope for the best'...chances are, whatever occurs will be somewhere in between. The two threats 'this blog' will mention as greatest relevance are 

1) Enhanced Flooding potential across areas already impacted by IRMA and the rain -event of several days ago;  and

 2) 'land-falling (tornadic) water-spout potential.

The second 'threat' is highly conditional; 
no forecast offices are referring to that chance as of this time. 

Just a heads up.

Of more immediate concern would be the 'flooding risk'. As of this hour the greatest risk appears to be for parts of Palm Beach, Martin, and St Lucie Counties southward in the 'rainfall arena' when all is said and done from beginning to end of 'said event'. 

Further north , the risk of 'waterspouts' might increase 
IF a surface low does in fact form.

In any case, most rains for at least most of Thursday will also be accompanied by stronger wind gusts at least initially. Wind direction will primarily be from the ENE-NE direction during this time period.

By Friday, wind will have weakened substantially as rains become  increasingly intermittent while the tropical waves moves on west away from the state. 

Elsewhere, chances are an Area of Investigation (INVEST) in the far SW Caribbean will develop into a NAMED system, 'Norm'. Current projections of said storm  imply this system will likely be too far to the west to impact the East Coast of Florida (going into early next week). That is to say, based on 'only current' projections.

 News stations and other outlets will be "Flooding the air waves" with more on this yet to be seen system in the next 24-72 hours as conditions develop.

Again, the blog will depict a worst case scenario, and there is a chance that some areas if not many will not see rainfall totals even half of what this graphic portrays. 

Any 'stronger wind associated with this upcoming 'event' will not be from a tropical storm, but rather pressure gradient wind between the low pressure over the Caribbean and a large high pressure area extending down the U.S. Eastern Seaboard and well out into the Western Atlantic from of the Mid-Atlantic states region. 

In fact, wind tomorrow might actually be a bit 'weaker' than has been for the past 24 hours and  much of today.

No one location will necessarily experience anything close to what is shown 'might be the case' , below. 

The most likely impacted areas appear to be in the regions from Vero Beach southward. 

Additionally, 'the 'greatest impact box' (purple)
 might need to be shifted further south.

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