NATL: MELISSA - Models

[mitchell]

If Melissa’s core misses Jamaica to the east, which I think will happen, was the GFS closest to being correct all along being the persistent right outlier?

5 days ago, the GFS had it northeast of the DR right now. No way to say anything but the GFS handled it horribly. Euro was slightly north of where it was now. 6z GFS is still too far east.

Yes - I remember a couple days ago noticing that the GFS still had it ejecting NNE across Haiti/DR and nowhere near Jamaica while virtually every other model had it drifting slowly west towards Jamaica. GFS run from just 2 days ago (in which it would be landfalling in Haiti now):

[cycloneye]

What a big change from GFS. Now is south of Jamaica.

[Blown Away]

12z ICON shifts to W end of Jamaica.

[LarryWx]

12Z Euro: goes back to an extent to the pre 0Z/6Z runs by being a bit further S of Jamaica thus helping it to get stronger (962) and thus it hits Jamaica at 971 instead of 986-8. It then goes back to a NE move over Jamaica and exits at 977 vs 992 of 0Z/6Z. As a result, the 20” line goes back further W to center of Jamaica.

[Kazmit]

Only took the GFS this long to show what the Euro has been showing for five days.

[TomballEd]

12Z Euro: goes back to an extent to the pre 0Z/6Z runs by being a bit further S of Jamaica thus helping it to get stronger (962) and thus it hits Jamaica at 971 instead of 986-8. It then goes back to a NE move over Jamaica and exits at 977 vs 992 of 0Z/6Z. As a result, the 20” line goes back further W to center of Jamaica.

I know you know this but models with 9 or 12 km resolution probably will be a bit too high with central pressure. (I'd probably split the difference between the HAFS B and the Euro) I do suspect the delay in RI means the possibility of a Cat 5 landfall is greatly reduced although a major seems a near certainty, although the big killer, the floods and mudslides won't be helped much.

[tolakram]

The GFS only corrected once shear was gone. That shear induced bias with an overly vigorous MLC is really really bad, except for the 1 time it actually worked out.

[USTropics]

The GFS only corrected once shear was gone. That shear induced bias with an overly vigorous MLC is really really bad, except for the 1 time it actually worked out.

The only reason these graphs go to 400 and 700 km respectively, is because the GFS missed that badly. Like you said, the GFS known bias with convective parameterization over the displaced MLC to the north and deepening the system there (which tugged the LLC north under it) was exponentially worse because of the fine line in steering.

[Blown Away]

00z Early model cluster slight W shift from 18z.

[sponger]

Something has to be done about addressing the GFS deficiencies in hurricane modeling. Its performance the last five years seems abysmal.

[jlauderdal]

Something has to be done about addressing the GFS deficiencies in hurricane modeling. Its performance the last five years seems abysmal.

AI hurricane models are right around the corner and we can put the globals where they belong, which is in the back seat The gfs euro battle will end and the AI models will be something to provide consistently correct solutions.

[Kazmit]

Both HAFS models now show peak intensity at landfall after a levelling off period over the next 24 hours. HAFS-B has it around 150kts, while HAFS-A, shown here, has a 155kt landfall.

[Hypercane_Kyle]

HAFS-A shows Melissa making landfall at an unbelievable 154 knots. It's crazy to think we are as far as 60 hours from landfall for Melissa. A lot of time for EWRC, intensifications, etc.

[USTropics]

12z HAFS-A coming in (I'm a HAFS-A hugger for Melissa ), it actually increases pressure some until about 8PM ET tonight (relative to what the run started at):


A new RI period begins shortly after that, with a drop to 931mb in 12 hours (8AM ET):

[kevin]

HAFS-B still shows an unbelievable landfall, 160 kt .

[Michele B]

12z HAFS-A coming in (I'm a HAFS-A hugger for Melissa ), it actually increases pressure some until about 8PM ET tonight (relative to what the run started at):
https://i.imgur.com/2MItvl1.png

A new RI period begins shortly after that, with a drop to 931mb in 12 hours (8AM ET):
https://i.imgur.com/zDtdlx6.png

OMG. How horrible it will be for them.

Are HAFS-A and/or B the new AI ?

[Sciencerocks]

HAFS-B still shows an unbelievable landfall, 160 kt .

https://i.imgur.com/cnLRhQN.png

certainly historic!

[Gums]

Salute!

Another Camille?

Only one I recall that had both the surge AND the wind. My Dad helped my Uncle a day or two after and said it was toothpicks... Andrew didn't have the surge due to ocean floor characteristics like Biloxi and Katrina. But Both Camille and Andrew had ferocious wind, then Michael in my neck of the woods 5 years ago. Shoreline topography really helped folks with Michael, and surprised many. Here.

Gums...

[cheezyWXguy]

12z HAFS-A coming in (I'm a HAFS-A hugger for Melissa ), it actually increases pressure some until about 8PM ET tonight (relative to what the run started at):
https://i.imgur.com/2MItvl1.png

A new RI period begins shortly after that, with a drop to 931mb in 12 hours (8AM ET):
https://i.imgur.com/zDtdlx6.png

Now that’s been a few hours since you made this post, and now that Melissa has resumed intensification, do you have any ideas as to what particular reason for the hafs’ leveling off and resuming of intensification? Do you think it was able to accurately see the dry air intrusion we observed, and do you think it could be due to the storm’s western inflow channel being blocked from moist inflow by Jamaica to the north? Is the resuming of intensification due to that channel no longer being blocked now that the storm has moved sufficiently westward?
Hope that wasn’t too many questions

[tropicwatch]

Salute!

Another Camille?

Only one I recall that had both the surge AND the wind. My Dad helped my Uncle a day or two after and said it was toothpicks... Andrew didn't have the surge due to ocean floor characteristics like Biloxi and Katrina. But Both Camille and Andrew had ferocious wind, then Michael in my neck of the woods 5 years ago. Shoreline topography really helped folks with Michael, and surprised many. Here.

Gums...

Michel 2018 would be another.