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This might well either impact the uk or the east coast if the US. 

Gfs 06z has again shifted westward, so certainly needs watching. 


Already quite a large storm with very nice Bandung  

A recent SSMIS microwave pass has revealed that the cyclone has
become much better organized with more pronounced convective
banding.  Satellite intensity estimates are wide ranging, spanning
from T1.5/25 kt from SAB to T3.4/53 kt from the UW-CIMSS ADT.  Since
the numbers overall have increased, and the structure has improved,
the initial intensity is raised to 35 kt, in closest agreement to
the TAFB estimate, but this could be conservative.  This makes the
depression Tropical Storm Florence, the sixth named storm of the

Florence is moving west-northwestward, or 285/12 kt, and should
maintain this motion for the next 48 hours while traveling along the
southern periphery of the subtropical ridge.  After 48 hours, the
storm is expected to reach a break in the ridge, causing it to slow
down and turn northwestward by day 5.  The biggest change noted
among the track models on this cycle was a westward shift in the
overall guidance envelope.  The European model, in particular, swung
significantly to the left, showing a weaker Florence not feeling the
break in the ridge quite as much.  I'd like to see this trend
continue before making a significant change to the forecast, so for
now the updated NHC track prediction is only nudged westward. That
said, the models appear to be trending away from a definitive
recurvature scenario.

The environment is mixed with positives and negatives for Florence's
strengthening.  For the first 3 days, vertical shear over Florence
should be quite low, but the cyclone will also be moving through a
less-than-ideal thermodynamic environment with marginal sea surface
temperatures and decreasing mid-level moisture.  After 3 days, the
thermodynamic environment should begin to improve, but then the
shear is forecast to strengthen. These conflicting signals point to
only gradual strengthening, and the suite of intensity models aren't
too far off from one another, nor from the previous NHC forecast.
For that reason, no significant changes were made in this forecast







Edited by Nick L
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Nice feed here    

Had to share this:  

This a beautiful satellite picture from NOAA showing the three tropical disturbances...

Posted Images

Ec will make a few take note. A fish this might well not be. 

Now that the models are initialising her more accurately, the shear is keeping her from strengthening. This in turns prevents a more northerly track and she misses the trough that would normally pick her up. Gfs 12z has shifted westwards as well, not as much but a similar theme. 

Unfortunately once she missed the trough. Ssts increase due to the gs and shear falls massively. Hence a major hurricane. 


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Florence certainly seems like a big storm. Currently boarderline cat 1 imho. Probably 60-65kts. ADT dvorak gives 62kts and radar 60kts. 

The size might indicate a gfs solution as it gets picked up more easily. However I am skeptical it will and would favour the ec solution that many of the models endorse. 


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Yes, Hurricane Florence (nice name).

Both GFS and Euro in unison for some time tonight in that they both agree that Florence feels a weakness in a few days but they then both agree that Florence slows to a crawl and strengthens (both major). They then argue about how it gets picked up.

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The models have taken a  much more interesting turn this morning. The ECM has a large high to the north of Florence which steers it towards the US coast with a landfall in the Carolinas by the end of next week.

The UKMO at 144 hours looks very similar to the ECM.

The GFS has also shifted Florence further west, it takes her very close to the east coast before moving away for a time but then makes a chenge of direction and eventually hit the far northeast US and Nova Scotia.

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Yes Florence surpassing expectations by a large margin, models were previously indicating it would die back to a tropical storm at this point but its now a strong category two.

A major change in its forecast track this morning, I fear this may be quite the headline grabber in 7-10 days time and eastern North America needs to watch this storm very closely.

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High Pressure building to its Northwest as it approaches the Seaboard, which makes GFS's loop the loop solution credible. Still too far out to really get any idea of whether it will make Landfall. ECM has it making landfall in the carolinas whilst CMC has it skirting and just missing the seaboard. Somewhere in between maybe ?



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Actually, the 6z GFS is spectacular in every sense! Florence becomes very troublesome for the whole of the eastern coast, Battering for days the Carolina coast as she stands stationary then slowly moving northwards where it makes landfall in the northeast. And then a major -AO and -NAO combination with the Arctic plunge for the UK.

Edited by karyo
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Well 4pm update confirms it. 125mph cat 3 major. Only 5 mph from a cat 4. 

The intensity seems to be slower her down a bit as well which is making problems. As it the ability for a large cane to throw up ridges and require more steering. 


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Have to say, it just goes to show the power of nature and the fact that it can surprise you, even with all the technology available at our fingertips. You'd have been given pretty high odds even a day and a half ago for Florence to be anywhere near a high end category 3 hurricane! Let's see what happens...

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According to dvorak it peaked an hr or so ago as a cat 4, but since declined a touch back to a high end cat 3  

ec shows a bad scenario of a probable cat 3-4 just if the coast for awhile

this is still along way off though and even 3 days will only bring any potential landfall into the outer reaches of reliable forecasting  

nice pin hole eye on sat  

12z models of the whole badly modelled initialisation though with most such as hwrf having a cat 1  




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Dvorak has gone up and down a touch but has stayed at 110-115kts. So either a low end cat 4 or high end cat 3 in the next advisory. 

Shear is having a very small affect mainly on outflow in the sw quad. 

However despite having ssts of only 27-28c she’s doing jncredibly. 

From sometime tomorrow ssts should rise above 28c. 

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Just after I finished the above they update. Inconsiderate. 

Florence has continued to intensify during the day, with colder
cloud tops completely encircling a clearer eye. Both subjective and
objective Dvorak estimates have unanimously increased to T6.0/115
kt, and on this basis, the initial intensity is raised to 115 kt,
making Florence a category 4 hurricane.


so she’s a cat 4 and the forecast is for only a little weakening before a return to a major hurricane again. 


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