40/70 Benchmark

Just wanted to acknowledge how impressive the insight was throughout this thread during the evolution of this historic hurricane. I certainly learned a lot about intensity forecasting and undoubtedly much more to learn. Here is my verification write up for those interested: Hurricane Ian Verification Offers Mixed Results Location and Timing of Landfall Forecast Nearly Flawless Here is how landfall of one of the most historic hurricanes in the history of the US, Hurricane Ian, evolved: Versus the Eastern Mass Weather Final Call, issued at roughly 730pm on Tuesday night: Fort Myers, FL was correctly identified as the most severely impacted major population center. Clearly the timing and location of the forecast was exemplary, having effectively incorporated climatology to disregard the consensus of guidance in the Monday night issuance of First Call: "Future Track of Ian Dependent Upon Interaction with Trough: Climo maybe the best Tool The track forecast is high confidence until Ian makes it around the western periphery of the high pressure node that is currently steering it into the southeastern Gulf of Mexico. It is at this point that it will being to turn towards the north and potentially even north northeast, as we approach mid week and it becomes under the influence of the northern periphery of the ridge and the base of a trough to the north. The primary question then becomes will it lose enough longitude to reach the west coast of Florida, or will it remain off of the coast (and how far) until reaching the panhandle...there is simply no way to know for sure and educated guesses will rule the day. Here is the guidance that will inform said "guesses": Hurricane Track Guidance and Global Guidance Note the cluster to the east, in the general vicinity of Tampa... European Ensemble Suite There is similar cluster on the European suite, which has been admittedly biased to the east over the course of the past few days. GFS Ensemble Suite: A similar, albeit less defined trend is noted on the GFS suite, as the western mean seems to be pulled by a scattering of western outliers, as opposed to a concentrated cluster. Canadian Ensemble Suite: With such a stark dichotomy in forecast track, which is so crucial to intensity, as will be discussed momentarily, climatology may be the best guidance with respect to the future track of Hurricane Ian. And this is potentially grave news for the Tampa Bay metro area. Here is a graphic courtesy of Matt Gross, which lists all of the major hurricane strikes between 1900 and 2010 throughout the state of Florida. Note that the best guidance clustering is definitely within the eastern climo cluster, in the vicinity if Tampa. While it is too early to be confident, this is where the likelihood is highest at this point in time. All residents in this area should rush preparations to protect life and property to completion over the next couple of days. Especially since it is this eastern track scenario that offers the most intense landfall potential." While it was reasoned that the more eastern track offered a more intense scenario. as it turned out the forecast was not nearly intense enough. Landfall Intensity Forecast Left Much to be Desired The logic all throughout the forecast period was that a more eastern track would result in a more intense hurricane strike. But complicating matters was that interaction with the higher terrain of wester Cuba induced a premature Eye wall Replacement Cycle (EWRC) as it re emerged int the se Gulf of Mexico. The forecast final forecast philosophy was that while the further south and east track would avoid much of the shear and dry air intrusion, these inhibiting factors would become just prevalent enough prior to landfall to retard the ability to the hurricane to fully recover from this EWRC. Thus it was not forecast to intensify significantly prior to landfall. However, Ian ended up recovering just about as proficiently and quickly as physically possible, and this coupled with the fact that its size allowed to be virtually impervious to the marginal mitigating factors allowed to take full advantage of some very high octane oceanic heat content. While this was alluded to as a possibility in the Final Call, it was not forecast. "The one caveat that bares watching is that if Ian should complete the aforementioned EWRC and conditions are not prohibitive to intensification, the oceanic heat content is very high just off of the coast of Fort Myers, so the possibility of late intensification, though not forecast, can not be ruled out. Thus the forecast intensity of 115mph was well short of the verified 150mph maximum sustained winds at landfall. FINAL GRADE: C

I thought I did a great job using climo as a tool to illustrate why the western edge of the track envelop was favored and that was dead on. Intensity forecasting is always a learning experience. This was from First Call on Monday: Future Track of Ian Dependent Upon Interaction with Trough: Climo maybe the best Tool The track forecast is high confidence until Ian makes it around the western periphery of the high pressure node that is currently steering it into the southeastern Gulf of Mexico. It is at this point that it will being to turn towards the north and potentially even north northeast, as we approach mid week and it becomes under the influence of the northern periphery of the ridge and the base of a trough to the north. The primary question then becomes will it lose enough longitude to reach the west coast of Florida, or will it remain off of the coast (and how far) until reaching the panhandle...there is simply no way to know for sure and educated guesses will rule the day. Here is the guidance that will inform said "guesses": Hurricane Track Guidance and Global Guidance Note the cluster to the east, in the general vicinity of Tampa... European Ensemble Suite There is similar cluster on the European suite, which has been admittedly biased to the east over the course of the past few days. GFS Ensemble Suite: A similar, albeit less defined trend is noted on the GFS suite, as the western mean seems to be pulled by a scattering of western outliers, as opposed to a concentrated cluster. Canadian Ensemble Suite: With such a stark dichotomy in forecast track, which is so crucial to intensity, as will be discussed momentarily, climatology may be the best guidance with respect to the future track of Hurricane Ian. And this is potentially grave news for the Tampa Bay metro area. Here is a graphic courtesy of Matt Gross, which lists all of the major hurricane strikes between 1900 and 2010 throughout the state of Florida. Note that the best guidance clustering is definitely within the eastern climo cluster, in the vicinity if Tampa. While it is too early to be confident, this is where the likelihood is highest at this point in time. All residents in this area should rush preparations to protect life and property to completion over the next couple of days. Especially since it is this eastern track scenario that offers the most intense landfall potential.

I did note in my write up that if it ever were able to successfully complete the EWRC, that is may really benefit from what was a high octane gulf stream eddy off of Fort Myers, which is what happened IMO....in addition to trough moving in unison with it and accentuating outflow. But at the end of the day, I just didn't think that it would be able to just "flip the switch" so soon after that terrain induced EWRC, and it did so about as proficiently will ever be observed. I saw all of the visual signs of it nearing completion when I posted the blog Tuesday night, but I just felt like it would just get caught up in that "stats quo" ..."looks better, but no increase in winds" situation. I was going to wait until Wed AM to do my final, but figured, "what fun is looking at the answers to the test before you release". I knew within about 2 hours my intensity forecast, along with the sw FL coast, was doomed.

Well, right, but I had it coming in at 115mph...that's a big miss. There were plenty of forecasts, that while not as aggressive as reality, were still decent. "F" for intensity, A+ for timing and locale.

I'll post my results later. I ended up really doing well on LF timing and location, but I was in your camp on incorrectly hedging against that late round of intensification. My "city of focus" was Fort Myers.

You wouldn't know but for the weenie reservoir tip at the top.

CFS looks mild, but not as warm as out west

I figured that to be the case when hearing so many had stayed. I was saying on social media that this would rival Katrina...even if it hadn't intensified IMO.

I can't get over the idiots playing in the surge in Fort Myers Beach around midday...wow. Anyone have a good RAD shot at point of landfall? Thanks

I think it just went out..

They probably factored that in to the surge forecast, I would think....

That's part of what I missed in expecting it to "only" come in as a cat 3. Its easy to lose sight of how impervious these things can grow to be to their surroundings. Amazing sequence over the past 12-24 hours....hope people got the hell out.

Completely agree. That is what I expected, though I knew this was possible. Yikes.

I agree its questionable whether the winds will ramp up much, but I don't think it really matters, unfortunately. That surge is going to be devastating. The wobble north may be good news for Fort Myers, anyway.

Interesting. I realized this was land induced, but did not realize that those type are usually quicker. I'll know why if I miss a round of intensification.

Here are my Final thoughts...for whatever that is worth haha https://easternmassweather.blogspot.com/2022/09/hurricane-ian-to-have-devastating.html

Often times, they just never regather that same initial, pristine structure and thus intensity (I call it the "skunked" look, with ragged CDO, etc)...other times, they end up even more ferocious, thereafter....Katrina was one such example.

Thanks for that graphic....I hadn't realized. Will use it.

If it remains impervious to the shear, then sure....tough to make that call, though. Obviously they should prepare for cat 4.

Truth be told, they probably are, too, but the fact of the matter is that lowering it isn't worth the risk of conveying the wrong message and having some let their guard down. Its relatively trivial in the grand scheme of things...

Right as it was emerging from Cuba earlier today, I thought that the disruption of its intensification may have meant that we wouldn't see an EWRC prior to LF in FL, however, it actually seems that said land interaction helped to trigger the cycle...which can happen. I am probably in the minority, but given that we are in the early stages of an EWRC with a large outer eye, shear is already beginning to impinge on the circulation and LF is a mere ~24 hrs away, I don't think that it will get much stronger. Main thing to watch for is how much the wind field can expand prior to LF, which will exacerbate surge. I had 130mph on my First Call as a peak intensity, and was nervous that was too conservative, but I hedged lower after seeing how long it took to get going in the NW Caribbean and factoring in the tenor of the season.

Looking at this, its def an EWRC IMO.

Sometimes interaction with land can help trigger them.

Its probably still trying to resolve some structural deficiencies that resulted from interaction with the higher terrain of Cuba.