ATL: OSCAR - Remnants - Discussion

[Nuno]

 https://twitter.com/burgwx/status/1847700103596855503

[jconsor]

I respectfully disagree - not clear at all this will be totally sheared apart by Mon. Most EPS members have it surviving into late this week and impacting Bermuda and the Canadian Maritimes. Will likely get a boost from interacting with a trough to its NW.

https://x.com/yconsor/status/1847713595594858849

https://i.ibb.co/FV158LZ/goes16-vis-swir-94-L-202410190212.gif

Also, ASCAT is doing what it does best, missing the system yet again

https://i.ibb.co/ctG83pq/ascat-94-L-202410190130.png

On the post season analysis, they will have to move up genesis to at least Friday night, perhaps earlier.

When I saw the satellite last night that had every hallmark of a tropical storm, I couldn't believe it was still the yellow lemon.

At least it will likely be short lived and by Monday should be completely sheared apart. If the remnant low level swirl goes SW or north is still uncertain.

[AJC3]

https://twitter.com/burgwx/status/1847700103596855503

Nothing surprising about that. Given their resolution, global models will invariably fail with TC genesis with systems on this tiny of a scale. Show me a model that catches this RI-ing (like your mesomodels/CAMS), and I'll show you the same model FA-ing TC-genesis with a bunch of other convective systems in the MDR.

[Hurricane2022]

I respectfully disagree - not clear at all this will be totally sheared apart by Mon. Most EPS members have it surviving into late this week and impacting Bermuda and the Canadian Maritimes. Will likely get a boost from interacting with a trough to its NW.

https://x.com/yconsor/status/1847713595594858849

https://i.ibb.co/FV158LZ/goes16-vis-swir-94-L-202410190212.gif

Also, ASCAT is doing what it does best, missing the system yet again

https://i.ibb.co/ctG83pq/ascat-94-L-202410190130.png

On the post season analysis, they will have to move up genesis to at least Friday night, perhaps earlier.

When I saw the satellite last night that had every hallmark of a tropical storm, I couldn't believe it was still the yellow lemon.

At least it will likely be short lived and by Monday should be completely sheared apart. If the remnant low level swirl goes SW or north is still uncertain.

I was about to post this thread here. But anyway, thanks for this great explanation.

[Travorum]

Pressure seems to have levelled out in the high 980s based on the most recent passes:

190400 2131N 07046W 6982 03111 0015 +094 +078 113067 074 068 063 01
190430 2130N 07047W 6934 03131 //// +104 //// 119053 077 079 034 01
190500 2128N 07048W 6980 03057 9893 +144 +115 100020 038 053 006 00
190530 2127N 07048W 6958 03085 9893 +143 +113 119010 015 041 002 03
190600 2125N 07049W 6973 03071 9894 +148 +109 213006 013 053 004 00
190630 2123N 07048W 6973 03085 //// +114 //// 264043 054 068 007 05
190700 2121N 07047W 6983 03111 //// +084 //// 243050 051 062 007 01

77kt FL / 79kt SFMR blends to 75kts in the NE, winds in the SW are expectedly lower.

[WaveBreaking]

Pressure seems to have levelled out in the high 980s based on the most recent passes:

190400 2131N 07046W 6982 03111 0015 +094 +078 113067 074 068 063 01
190430 2130N 07047W 6934 03131 //// +104 //// 119053 077 079 034 01
190500 2128N 07048W 6980 03057 9893 +144 +115 100020 038 053 006 00
190530 2127N 07048W 6958 03085 9893 +143 +113 119010 015 041 002 03
190600 2125N 07049W 6973 03071 9894 +148 +109 213006 013 053 004 00
190630 2123N 07048W 6973 03085 //// +114 //// 264043 054 068 007 05
190700 2121N 07047W 6983 03111 //// +084 //// 243050 051 062 007 01

77kt FL / 79kt SFMR blends to 75kts in the NE, winds in the SW are expectedly lower.

And seeing how the eye more than doubled in size between VDMs, Oscar is probably working out some internal structure problems, or it might’ve just had a really quick “fun”-sized EWRC.

[ScottNAtlanta]

Huh???? Leave for a day 10% to 90%
Leave a couple more hours it's a hurricane

[Fancy1002]

That was quick, skipped right past tropical storm, and straight to hurricane.

[AJC3]

Pressure seems to have levelled out in the high 980s based on the most recent passes:

190400 2131N 07046W 6982 03111 0015 +094 +078 113067 074 068 063 01
190430 2130N 07047W 6934 03131 //// +104 //// 119053 077 079 034 01
190500 2128N 07048W 6980 03057 9893 +144 +115 100020 038 053 006 00
190530 2127N 07048W 6958 03085 9893 +143 +113 119010 015 041 002 03
190600 2125N 07049W 6973 03071 9894 +148 +109 213006 013 053 004 00
190630 2123N 07048W 6973 03085 //// +114 //// 264043 054 068 007 05
190700 2121N 07047W 6983 03111 //// +084 //// 243050 051 062 007 01

77kt FL / 79kt SFMR blends to 75kts in the NE, winds in the SW are expectedly lower.

Outer fringes of the circulation are starting to reach the remnant shear line associated with the cooler, more stable post-frontal air mass. Might start to see the NW flank of Oscar's satellite presentation flatten tonight as the convection in that quadrant collapses. We'll see...

[Sciencerocks]

[zzzh]

[CrazyC83]

I agree with 75 kt based on that last pass, assuming that dropsonde is a bit inflated.

My guess is genesis will be moved up to 00Z or 06Z but still that was quick...

[ChrisH-UK]

Oscar is a clear case of a storm been too small for the global models to see and the TC models that feed of the global models also don't see it even when the mark 1 eyeball clearly see's something.

[Hurrilurker]

And last I heard the power grid for the entire island of Cuba was down...not good.

[CrazyC83]

HY-2C scatterometer at 0852Z had at least one 35 kt wind, along with evidence of an LLC. This one has no future. It will soon be butting up against a wall of SW-NE wind shear that reaches the central Bahamas. Small systems like this can strengthen quickly and weaken quickly. I was debating whether it would shoot off to the NE when it tracks a bit farther west of if the moisture would shoot off NE and the weak low-level swirl continue to eastern Cuba. I'm leaning more toward the second scenario.

Historic. In just three hours, this aged like milk...

In fairness, he did say that small systems strengthen quickly so he did point that out.

If I were to adjust the BT (very preliminary)

00Z (genesis as TD) - 30 kt, 1010 mb
06Z - 40 kt, 1005 mb (based on that HY-2C and low resolution)
12Z - 55 kt, 998 mb (based on that microwave imagery with partial eyewall)
18Z - 75 kt, 989 mb

In fact, you could even argue genesis could move back to 18Z yesterday, although the ASCAT was inconclusive at the time.

[PDKlikatino]

Just when we'd thought 2024 was starting to wind down with this sort of ridiculousness it somehow surprised us yet again!

[zzzh]

There is a bit of northwesterly shear.

[CrazyC83]

If this enters the shear zone, this could unravel very quickly. But if it stays a bit south, it could definitely get stronger.

[aspen]

Definitely starting to look like it’s feeling shear on visible imagery.

Such a weird storm. Tracked on the models for over a week as it approaches the Caribbean. Model support drops. Then it suddenly forms and becomes a super tiny hurricane before getting sheared. It sprouted once most had basically given up on its precursor, which seems to be a common theme with storms this year (Francine, Milton, Nadine, and now Oscar).

[Woofde]

Wow, I was reading about the Cuba situation. Someone in the thread said " There's now a surprise hurricane headed to make things worse." I thought no way maybe they're mistakenly thinking of Nadine? Looked at the NHC website and sure enough... This one slipped under the radar hard.

Such a tiny core, and it's right on the line between high shear and a lower shear area. This could fall apart in an instant or really surprise people, I hope it's the former or this could be a disaster given what Cuba is already dealing with.