ATL: GRACE - Remnants - Discussion

[aspen]

982.6 mbar ! First pass by recon, now also updated on TropicalAtlantic. Looks like Grace is back at hurricane strength and earlier than forecast by the already agressive HMON and HWRF.

Extrapolated Sfc. Pressure = 982.6 mbar
SFMR = 74 kt
Est. Sfc. Wind = 72 kt

And it doesn’t make landfall until midnight…a Cat 3 is looking a lot more plausible now. The next pass will tell us how quickly it’s deepening.

[aspen]

Center drop was 984/12, supporting 982 or 983mb.

[ElectricStorm]

Wow that's exactly what I did NOT want to see when I woke up. That's 10mb deeper than the 0z HMON and HWRF showed for now. And both of them got down to the 960's

[AlphaToOmega]

That was some quick intensification.

[Chris90]

I was not really expecting Grace to be this far along already. I thought she was more likely going to have a pressure around 988-992mb. 92kt flight level winds were also a bit more than I expected. Increased chances for a major at this point I would say, which is unfortunate for Mexico. I didn’t really think she would have enough time, but at this point it doesn’t look like it’ll be an issue.

[cycloneye]

 https://twitter.com/pppapin/status/1428687538080919554

[ThetaE]

Center drop was 984/12, supporting 982 or 983mb.

Some extra thought should probably be given to the typical pressure reduction, since the AF plane showed a pretty interesting structure. Overall, I think Grace has a surprisingly broad/flat eye for such a strong NE quadrant and pressure above 980mb. This is best explained by what appears to be a mesovortex on the NE side, with the 982.6 mb minimum being measured in a region of ~40kt sfc and flight level winds. The wind shift, on the other hand, happened on the SW side of the eye (extrap. 985.3 mb).

Based on lat/lon, looks liked that center dropsonde was at the wind shift, not the mesovort. Not sure how the NHC typically handles these features, but you could make an argument for 979-980 mb inside the mesovortex.

[Owasso]

100kt winds just above the surface

[Hypercane_Kyle]

Bay of Campeche working its magic unfortunately. Reminds me of Karl in 2010.

[cheezyWXguy]

This has major written all over it. First visible of the day appears to be revealing overshooting tips surrounding a developing mid level eye.

[ElectricStorm]

It's about halfway across the BOC and it's already at the NHC's landfall intensity
Karl in 2010 blew up almost to a Cat 4 on a similar track. Hopefully Grace doesn't do the same

[kevin]

Grace now also officially back to hurricane status.

[ElectricStorm]

982.8 extrap

[tolakram]

Grace floater https://weather.cod.edu/satrad/?parms=meso-meso1-02-24-1-100-1&checked=map&colorbar=undefined

[tolakram]

saved Radar loop

[Iceresistance]

982.9 being reported several times, lowest was 982.8 (Reported twice on the previous update)

[ElectricStorm]

Eye drop supports 982mb

[aspen]

That crescent-shape CDO with a possible dry slot in the south could limit intensification for the time being.

[Teban54]

That crescent-shape CDO with a possible dry slot in the south could limit intensification for the time being.

Grace had that structure for a few hours already, and that didn't seem to stop it from intensifying. I remember Teddy also looked similar as a Cat 2 with a semi-circle-like CDO on the eastern side.

[ElectricStorm]

That is a pretty decent dry slot there but so far it hasn't done much to stop strengthening. Hopefully Grace won't be able to close it off but with all that convection I would think it would close off eventually.