ATL: SAM - Remnants - Discussion

[grapealcoholic]

Cooler waters taking a toll it seems

[cheezyWXguy]

939.3 extrap.

What a baffling storm to track.

125kt FL, 125kt (flagged) SFMR as well. A little weaker than last night but not all that surprising since it took a minor hit from shear this morning. This has been a daily occurrence for the whole week though - a brief hit from shear in the early morning, followed by steady improvement through the day

[Hypercane_Kyle]

125 knot SFMR, but flagged. I'd put Sam at 120 knots now.

Something funky is going on with the recon though. Did a 180 in the eye, like an aborted NE eyewall intercept attempt.

[grapealcoholic]

125 knot SFMR, but flagged. I'd put Sam at 120 knots now.

It's a big storm so there's about a 10% undersampling of winds. Also still need to see the other quads

[kevin]

152 kt FL winds in the NE quadrant!

[ElectricStorm]

Are my eyes deceiving me or is that a 152 that just popped up

[Iceresistance]

And the lowest Extrapolated Pressure is 937.8 MB

[grapealcoholic]

Absolute beast of a storm

[kevin]

Okay this might be a lot, a lot closer to a cat 5 than I thought. 152 kt supports an upgrade to 135 kt, but is just on the edge for a possible 140 kt upgrade especially since SFMR is relatively low. 155 - 156 kt FL winds would probably be sufficient. But considering that Sam is still improving and that we might get another 1 or 2 passes I think this now has a realistic chance to get a cat 5 peak.

[cheezyWXguy]

152 kt FL winds in the NE quadrant!

Looks like they missed the center too, xtrap dropped to 937.1 as the winds started coming back up

[aspen]

An increase in pressure, but wow those FL winds. 135 kt seems like a good estimate now. It’s very strange how low SFMR is in the NE quad.

[kevin]

Eye temperature has also increased to 18.1C.

[grapealcoholic]

I would go with 140 to account for undersampling.

[kevin]

I know it was only done in post-analysis, but note that they also went with 140 kt for Michael based on a 152 kt FL measurement.

[Sciencerocks]

[InfernoFlameCat]

Sam is. going for cat 5.
Lorenzo Style.

[NotoSans]

Looks like what some posters have suspected is indeed correct. It is not uncommon for storms benefiting from trough interaction but with a weak southern eyewall to find it difficult to mix winds effectively to the surface. Zeta last year has flight-level winds that obviously supporting something above 100kt, but NHC at last goes only with 100kt, adopting a lower-than-usual conversion factor.

The best estimate is 125-130kt based on a blend of flight-level and SFMR data.

[HurricaneEnzo]

An increase in pressure, but wow those FL winds. 135 kt seems like a good estimate now. It’s very strange how low SFMR is in the NE quad.

Not really. These higher latitude storms with warmer convection don't mix those winds in the upper levels of the system down to the surface as efficiently. Pretty common thing to see when we get recon on storms in this part of the world. Slightly stronger than I anticipated though 120-130kts would probably be good. I'm guessing they would probably go with a .8 conversion in this scenario.

[NotoSans]

I know it was only done in post-analysis, but note that they also went with 140 kt for Michael based on a 152 kt FL measurement.

Post-analysis finds SMFR (not flight-level) winds of 152kt for Michael, although the data is deemed somewhat inflated. Also, recon data shows the standard 0.9 conversion factor does apply to Michael, but not necessarily the case for Sam.

[kevin]

One thing that might be in Sam's favor for a possible cat 5 upgrade is that it has a fantastic wind field. The 152 kt FL wind isn't a weird outlier surrounded by 110 kt or something like that, but the windfield very gradually slopes down as recon leaves Sam's center: 144-152-145-137-135-132-126-121.