Hurricane Francine

[GaWx]

12Z UKMET: similar C LA landfall location/timing (PM of 9/11) to 0Z run but stronger at 990 mb vs 996 mb (winds of 40 knots too light imo but that’s a model bias this far out). Also, this run then goes NNE up Miss River to Memphis instead of NE to far E TN:

TROPICAL STORM 91L        ANALYSED POSITION : 20.2N  93.8W

     ATCF IDENTIFIER : AL912024

                        LEAD                 CENTRAL     MAXIMUM WIND
      VERIFYING TIME    TIME   POSITION   PRESSURE (MB)  SPEED (KNOTS)
      --------------    ----   --------   -------------  -------------
    1200UTC 08.09.2024    0  20.2N  93.8W     1004            37
    0000UTC 09.09.2024   12  20.4N  93.9W     1003            36
    1200UTC 09.09.2024   24  21.8N  94.2W     1003            40
    0000UTC 10.09.2024   36  23.1N  94.9W     1002            39
    1200UTC 10.09.2024   48  24.7N  95.8W      999            40
    0000UTC 11.09.2024   60  25.6N  95.3W      995            35
    1200UTC 11.09.2024   72  27.7N  93.6W      990            49
    0000UTC 12.09.2024   84  29.8N  91.2W      990            40
    1200UTC 12.09.2024   96  32.7N  90.8W      992            27
    0000UTC 13.09.2024  108  35.0N  90.2W      995            22
    1200UTC 13.09.2024  120  36.3N  89.5W     1002            16
    0000UTC 14.09.2024  132  37.4N  88.8W     1007            19
    1200UTC 14.09.2024  144              CEASED TRACKING

[GaWx]

12Z Euro: much stronger, quicker, and further E at landfall than prior runs with 978 mb H at late Wed evening C LA landfall, similar location/timing to 12Z UKMET. It then like the UK turns NNE up/near the Miss River.

[hawkeye_wx]

3 minutes ago, GaWx said:

12Z Euro: much stronger, quicker, and further E at landfall than prior runs with 978 mb H at late Wed evening C LA landfall, similar location/timing to 12Z UKMET. It then like the UK turns NNE up/near the Miss River.

[WxWatcher007]

1 hour ago, Normandy said:

^not sure about the inhibiting factors.  The models are showing the deepening fast as it accelerates NE.  The fast NE motion might yield a more positive interaction with the jet streak to its north (less shear)

I think it depends largely on what you said, is the trough interaction going to be ideal with a further NE turn like the GFS/Euro, or a little flatter and thus more hostile like the Canadian. I lean toward the former, but I don’t think it’s a lock. 

[GaWx]

 Ironically considering how this season so far has appeared to many: IF this were to hit the US as a H and based on the model consensus timing, it would be the earliest 3rd H hit on the CONUS since way back in 2005! Only 10 of 173 years since 1851 (6%) would have had an earlier 3rd H hit with only 2 of those during the internet era. They are 2005, 2004, 1985, 1934, 1933, 1916, 1893, 1886, 1879, and 1871. So, in this way at least, not at all a quiet season so far.

 
Edit: Oops, I somehow left off 2020, which had its 3rd US H landfall on LA on 8/27 from Ida. So, it hasn’t been since 2005. Revises it from 10 to 11 of the 173 years (still 6%) with #3 before the expected upcoming LA landfall.

[WxWatcher007]

Recon has entered the system, so we’ll get a good sense soon of whether we have a well defined center. 

[StantonParkHoya]

27 minutes ago, GaWx said:

 Ironically considering how this season so far has appeared to many: IF this were to hit the US as a H and based on the model consensus timing, it would be the earliest 3rd H hit on the CONUS since way back in 2005! Only 10 of 173 years since 1851 (6%) would have had an earlier 3rd H hit with only 2 of those during the internet era. They are 2005, 2004, 1985, 1934, 1933, 1916, 1893, 1886, 1879, and 1871. So, in this way at least, not at all a quiet season so far.

it’s just an oddity because all of the small number of storms have found land

it is objectively a quiet season so far when your point of measure is a predicted 25 named storms

[WxWatcher007]

Everything that’s developed has hit land. Even Ernesto somehow found Bermuda. Just an odd quirk of a season that started hot but then had a historically inactive period during peak season. 

Recon just starting and already finding 40-45kt winds, consistent with earlier ASCAT partial pass. 

[purduewx80]

GOES and ASCAT (below) both suggest 90L's remnant is tighter. Hopefully recon is able to sample both circulations.

[Normandy]

Very strong inflow coming into this new burst.  Still have multiple centers though but the windfield on the west side is already stout.  Very WPAC like look

[purduewx80]

Advisories on PTC6 will start up at 5E/4C.

[CurlyHeadBarrett]

[nycwinter]

nhc is underplaying the intensity at landfall just making hurricane strength..

[WxWatcher007]

Still some uncertainty on the trough interaction so that’s not surprising 

[Normandy]

The explosive convection is telling.  Ceiling is high for this one.  If it can catch a positive trough interaction (and let’s be honest the more convection produces the better chance that happens) this could go nuclear.  Look at the outflow in all quads.  Upper level support is great.

in terms of track im also east.  I think this gets very strong and thus I think it gets yanked NE fairly briskly and feels that weakness.  New Orleans would be at risk if this plays out 

[Windspeed]

nhc is underplaying the intensity at landfall just making hurricane strength..

They're not going to forecast a strong hurricane with several key variables being uncertain. Genesis has yet to occur. The phasing of the frontal low and the tropical surface low is still evolving, and a broader circulation could prolong development prior to any potential period of RI. Even if the upper-level flow looks favorable, mid-level flow could advect an arid airmass into the circulation out of Mexico/Texas prior to the core becoming dominant to shield itself. I do think this becomes a hurricane as it has enough time over high heat content. But I would be reluctant to forecast a major. Of course, now that I have said that, it will go full Opal thanks to Murphy's Law.

[gallopinggertie]

50 mph even though it’s still just a potential cyclone, wow.

[CurlyHeadBarrett]

To restate, the intense deepening depicted on the GFS is the result of baroclinic support due to the trough interaction. This could improve outflow and allow for quick deepening in spite of theoretically high shear. Humbertomaxxing interactions are usually quite hard to forecast, and depend on placement with respect to the trough and a generally well-organized system prior to the onset of the interaction. It’s not shown on all models but will be something to watch out for with 6L.

[NorthHillsWx]

These jet-enhanced storms are usually reserved for later in the season, especially in the GOM. But goes to show the anomalously strong trough over the east coast. Freeze warnings in Virginia tonight! As for the storm itself, I could see one of two outcomes. A strong half-a-cane due to positive trough interaction or a sheared storm that never gets its act together. Don’t think this one’s going to be eye candy regardless of final intensity. Really reminds me of Nicholas from a couple years ago. Another interesting thing is how quickly models turn this thing into a sprawling post-tropical system after landfall. It’s possible this storm could have some non-tropical features as it approaches the coast and interacts with said trough. Really going to be an interesting evolution and I think it’s going to be very much up in the air 24 hours from now. My gut tells me this maxes out 80-90 mph and we see our third gulf storm landfall of the exact same intensity this season. One thing to watch as this organizes is whether or not it can develop a small core or if it stays broad. Broad in this case where jet interactions will ultimately dictate final intensity will surely mean this struggles to reach H Intensity. A tight core will have a much better shot, despite the shear likely to inhibit it’s appearance 

[CurlyHeadBarrett]

2 hours ago, NorthHillsWx said:

These jet-enhanced storms are usually reserved for later in the season, especially in the GOM. But goes to show the anomalously strong trough over the east coast. Freeze warnings in Virginia tonight! As for the storm itself, I could see one of two outcomes. A strong half-a-cane due to positive trough interaction or a sheared storm that never gets its act together. Don’t think this one’s going to be eye candy regardless of final intensity. Really reminds me of Nicholas from a couple years ago. Another interesting thing is how quickly models turn this thing into a sprawling post-tropical system after landfall. It’s possible this storm could have some non-tropical features as it approaches the coast and interacts with said trough. Really going to be an interesting evolution and I think it’s going to be very much up in the air 24 hours from now. My gut tells me this maxes out 80-90 mph and we see our third gulf storm landfall of the exact same intensity this season. One thing to watch as this organizes is whether or not it can develop a small core or if it stays broad. Broad in this case where jet interactions will ultimately dictate final intensity will surely mean this struggles to reach H Intensity. A tight core will have a much better shot, despite the shear likely to inhibit it’s appearance 

Do you remember that one hurricane that peaked as a borderline category 4 in 2019 in 70 knots of shear?

[Floydbuster]

 

[GaWx]

0Z UKMET: lowest SLP (993) slightly higher than 12Z; similar landfall location and slightly earlier (late afternoon Wed 9/11); goes a little E of Memphis (slightly E of 12Z); then NE into KY:

NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER  12 HOURS
              FORECAST POSITION AT T+ 12 : 22.3N  93.8W

                        LEAD                 CENTRAL     MAXIMUM WIND
      VERIFYING TIME    TIME   POSITION   PRESSURE (MB)  SPEED (KNOTS)
      --------------    ----   --------   -------------  -------------
    1200UTC 09.09.2024   12  22.3N  93.8W     1004            35
    0000UTC 10.09.2024   24  23.8N  94.9W     1003            34
    1200UTC 10.09.2024   36  24.8N  95.2W     1000            37
    0000UTC 11.09.2024   48  26.4N  94.0W      996            37
    1200UTC 11.09.2024   60  28.5N  93.0W      993            45
    0000UTC 12.09.2024   72  30.3N  90.9W      993            33
    1200UTC 12.09.2024   84  32.8N  90.4W      995            24
    0000UTC 13.09.2024   96  35.0N  90.0W      997            23
    1200UTC 13.09.2024  108  35.6N  89.3W     1003            13
    0000UTC 14.09.2024  120  36.7N  87.7W     1008            14
    1200UTC 14.09.2024  132              CEASED TRACKING

[GaWx]

0Z Euro: not quite as strong as 12Z with 983 (vs 979) mb at LA landfall; like 12Z goes to Memphis area at 997 mb

[NorthHillsWx]

Convectively this system is impressive. Instability and moisture are not inhibiting factors for development today 

[olafminesaw]

Not your typical  hurricane!

[40/70 Benchmark]

Not too engaged on this one, but my inclincation is that final LF intensity will be comparable to Beryl in TX.

[LongBeachSurfFreak]

35 minutes ago, NorthHillsWx said:

Convectively this system is impressive. Instability and moisture are not inhibiting factors for development today 

Insane water temps will do that. I agree with your earlier comment that we have a halfcane  coming with this one. 

[WxWatcher007]

14 minutes ago, olafminesaw said:

Not your typical  hurricane!

That’s the kind of signal where the right track could cause extremely efficient ventilation. Or, any deviation from that “ideal” track blasts the system right before landfall. 

Things look like they’re a go for intensification later, and it’s kind of impressive we’re getting this with the rest of the Gulf under high shear. ULAC saves the day I guess. 

[olafminesaw]

25 minutes ago, WxWatcher007 said:

That’s the kind of signal where the right track could cause extremely efficient ventilation. Or, any deviation from that “ideal” track blasts the system right before landfall. 

Things look like they’re a go for intensification later, and it’s kind of impressive we’re getting this with the rest of the Gulf under high shear. ULAC saves the day I guess. 

What is ideal track? A bit right of the current NHC track?

[WxWatcher007]

7 minutes ago, olafminesaw said:

What is ideal track? A bit right of the current NHC track?

Maybe a touch more NE, but the real critical factor imo will be how strong an inner core the system has as it’s approaching the coast. If it’s a weak inner core, shear could cause last second weakening as the vortex gets tilted and drier air gets imparted. You can see on the HWRF how the core is only half complete. 

 

Other models are closer to closed but not quite there and as a result pressures are lower.

 

I’d just caution that we don’t have a well defined center yet, so both final track and especially intensity are far from settled matters. Shear and dry air lurk, but on the other side of the equation we see very strong convection and western Caribbean like OHC along the the projected track of the system that should favor continued deep convection.