ATL: DORIAN - Post-Tropical - Discussion

[NotSparta]

The unflagged 141kt SFMR had an extremely high rain rate of over 2in/hr.

A sonde landed in southerly winds w/ 118kts, factoring in system speed which affects wind on north side, closer to 130kt max is reasonable

[Kazmit]

Cat 5 will be a close call for sure. It will probably be peaking soon.

[Aric Dunn]

Ok what did i miss lol..

[NDG]

Still some nice ridging to the north of Dorian, 592dm heights at h50 along the SE Coast, also look at the easterly winds in the mid levels over Miami, that mid to upper level low to the SW of Dorian might still be influencing it.

[Jr0d]

It is important to note key factors the models missed. IF current observations show the models over/underestimated the ridge ULL, and/or the strength and timing of the trough, as well as the speed and direction of the storm there will be major errors on those models.

This one thing the pros do best. Especially at the NHC. Model interpretation and making adjustments to the forecast track based on observed errors with model runs is crucial for accurate forecasting.

There is a reason the NHC forecasted track is much more accurate than the best computer models.

[Canelaw99]

Still some nice ridging to the north of Dorian, 592dm heights at h50 along the SE Coast, also look at the easterly winds in the mid levels over Miami, that mid to upper level low to the SW of Dorian might still be influencing it.

https://i.imgur.com/X2GICRy.gif

And what does this mean ?

[La Sirena]

Ok what did i miss lol..

At least 5 more people gave the all clear for Florida, some mused that Dorian will be a Cat 5 by 11 am today, surface winds reported to be around 135 kts, the interesting little westerly track it’s taking, and the fact that the NHC moved the track right....I think that covers it

[GCANE]

The diabatic ridge may slow down Dorian's forward motion more if intensification continues.
Possible it may miss the effects of the Midwest Trough.

[NDG]

Still some nice ridging to the north of Dorian, 592dm heights at h50 along the SE Coast, also look at the easterly winds in the mid levels over Miami, that mid to upper level low to the SW of Dorian might still be influencing it.

https://i.imgur.com/X2GICRy.gif

And what does this mean ?

If ridging stays stronger than what the models show a more westward track of Dorian before the ridge starts weakening and starts slowing down before feeling the weakness developing in a couple of days or so. IMO.

[1900hurricane]

Still some nice ridging to the north of Dorian, 592dm heights at h50 along the SE Coast, also look at the easterly winds in the mid levels over Miami, that mid to upper level low to the SW of Dorian might still be influencing it.

https://i.imgur.com/X2GICRy.gif

My eyes are on the shortwave traversing the Mississippi Valley right now. That's what is going to weaken the ridging and potentially break down steering.

[feederband]

https://www.accuweather.com/en/bs/nassa ... u61HqDT2dQ

[Ntxw]

Will be interesting if recon finds a Cat 5 later today barring conventional methods estimates don't meet that (purpose of other basins) . The visible images are stunning but scary seeing the landmasses.

[USTropics]

 https://twitter.com/TropicalTidbits/status/1167797656250396672




 https://twitter.com/TropicalTidbits/status/1167782628059226113




 https://twitter.com/TropicalTidbits/status/1167774709808865280

[1900hurricane]

12Z best track data has the Integrated Kinetic Energy (IKE) at a comparable level to Harvey '17 at peak intensity, both about 24 TJ, just in case people are wondering about size comparisons. Also similar to Andrew '92 (~25 TJ using CSU's enhanced best track wind radii).

[Jr0d]

Who remembers when John Hope used to say on TWC that the flow of the high cirrus clouds was a sign to follow of where the Hurricane was headed? So true!

Definitely something to keep in mind after a wild model shift.

I think you can see this with Hurricane Matthew? I watched a few times and the theory seemed to hold true, at least with that storm. I tried to see if I could see the effect with Irma footage, but that storm was just so dang BIG, I couldn’t tell what I was looking at. It would be interesting to see if anyone could find the effect with Irma, though, just because the three day forecast swung so much with her.

https://youtu.be/HPALhC_OtXk

I am going to have to find some larger scale satellite views of past storms to really study this.

It is quite concerning those high clouds are aimed at S/CFL for sure. None of us want to see a landfall there.

We do not want John Hope to be right in this case, but I would not bet against his wisdom.

[jlauderdal]

Ok what did i miss lol..

At least 5 more people gave the all clear for Florida, some mused that Dorian will be a Cat 5 by 11 am today, surface winds reported to be around 135 kts, the interesting little westerly track it’s taking, and the fact that the NHC moved the track right....I think that covers it

john morales on nbc miami sure is optimistic this morning

https://twitter.com/JohnMoralesNBC6/sta ... 0252784640

If the current NHC forecast track for Dorian were to be 100% accurate, the Keys, Miami-Dade *and* Broward counties would be left *out* of the tropical storm force wind field! Optimism grows, and this morning's models allow for my confidence level to grow too!

[Aric Dunn]

yeah seems like ridging and steering is hold strong for now. all this westward motion should have effects on the 12z models. dorian was supposed to arch to the wnw not come straight west which will make it possibly come in farther south.

[Hypercane_Kyle]

VDM suggests Dorian may have become a Category 5.

Product: Air Force Vortex Message (URNT12 KNHC)
Transmitted: 31st day of the month at 13:49Z
Agency: United States Air Force
Aircraft: Lockheed WC-130J Hercules with reg. number AF96-5302
Storm Number & Year: 05 in 2019
Storm Name: Dorian (flight in the North Atlantic basin)
Mission Number: 23
Observation Number: 11

A. Time of Center Fix: 31st day of the month at 13:27:10Z
B. Center Fix Coordinates: 25.88N 73.17W
B. Center Fix Location: 268 statute miles (431 km) to the ENE (78°) from Nassau, Bahamas.
C. Minimum Height at Standard Level: 2,622m (8,602ft) at 700mb
D. Minimum Sea Level Pressure: 945mb (27.91 inHg)
E. Dropsonde Surface Wind at Center: From 85° at 8kts (From the E at 9mph)
F. Eye Character: Closed
G. Eye Shape & Diameter: Circular with a diameter of 14 nautical miles (16 statute miles)
H. Estimated (by SFMR or visually) Maximum Surface Wind Inbound: 141kts (162.3mph)
I. Location & Time of the Estimated Maximum Surface Wind Inbound: 10 nautical miles (12 statute miles) to the NE (42°) of center fix at 13:24:00Z
J. Maximum Flight Level Wind Inbound: From 125° at 131kts (From the SE at 150.8mph)
K. Location & Time of the Maximum Flight Level Wind Inbound: 10 nautical miles (12 statute miles) to the NE (42°) of center fix at 13:24:00Z
L. Estimated (by SFMR or visually) Maximum Surface Wind Outbound: 117kts (134.6mph)
M. Location & Time of the Estimated Maximum Surface Wind Outbound: 6 nautical miles to the SW (227°) of center fix at 13:29:00Z
N. Maximum Flight Level Wind Outbound: From 312° at 108kts (From the NW at 124.3mph)
O. Location & Time of the Maximum Flight Level Wind Outbound: 6 nautical miles to the SW (227°) of center fix at 13:29:00Z
P. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 8°C (46°F) at a pressure alt. of 3,086m (10,125ft)
Q. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 19°C (66°F) at a pressure alt. of 3,044m (9,987ft)
R. Dewpoint Temp & Sea Surface Temp: Not Available
S. Fix Determined By: Penetration, Radar, Wind, Pressure and Temperature
S. Fix Level: 700mb
T. Navigational Fix Accuracy: 0.02 nautical miles
T. Meteorological Accuracy: 1 nautical mile

Remarks Section:

Maximum Flight Level Wind: 131kts (~ 150.8mph) which was observed 10 nautical miles (12 statute miles) to the NE (42°) from the flight level center at 13:24:00Z

[Evenstar]

The diabatic ridge may slow down Dorian's forward motion more if intensification continues.
Possible it may miss the effects of the Midwest Trough.

Is there a difference between a diabatic ridge compared to other types (assuming there are other types) of ridges? Something tells me "diabatic" has nothing to do with blood sugar levels, so I thought I'd ask.

[cycloneye]

Ok what did i miss lol..

Is there a circulation?