ATL: DANIELLE - Post-Tropical - Discussion

[Kingarabian]

Probably a lot of revising in the off season.

[Jelmergraaff]

Honestly - if what I see on satellite imagery is a real eye - this 'storm' should at least be a cat. 1 hurricane.

[Yellow Evan]

TXNT21 KNES 020621
TCSNTL

A. 05L (DANIELLE)

B. 02/0530Z

C. 37.9N

D. 43.6W

E. ONE/GOES-E

F. T4.5/4.5

G. IR/EIR/SWIR

H. REMARKS...A WMG EYE SURROUNDED BY A MG RING AND EMBEDDED IN MG RESULTS
IN A DT OF 4.5. 6 HOUR AVERAGING ALSO RESULTED IN A DT OF 4.5. THE MET
IS 3.0 BASED ON A 24 HR RAPID DEVELOPING TREND. THE PT IS 3.5. THE FT IS
BASED ON THE 6 HOUR AVERAGE DT WHICH JUSTIFIES BREAKING THE CONTRAINTS
LIMITING THE FT TO A CHANGE IN 1.0 OVER 6 HOURS.

I. ADDL POSITIONS

NIL


...GATLING

[galaxy401]

I think the NHC will jump to hurricane status next advisory. That 4.5 reading might decide it.

[Sciencerocks]

[Jelmergraaff]

NHC has put it at 70 mph for now.

Satellite imagery shows that Danielle is continuing to strengthen, with convective bands wrapping around the center and attempts at eye formation. The various satellite intensity estimates have a wide range from 45-77 kt, and the consensus of the estimates is that Danielle is not quite a hurricane yet. Based on these estimates, the initial intensity is increased to a possibly conservative 60 kt.

[Hammy]

60kt. I don't normally support criticizing NHC decisions, but

The various satellite intensity estimates have a
wide range from 45-77 kt, and the consensus of the estimates is
that Danielle is not quite a hurricane yet.

Clearly the 45kt one is wrong and it makes absolutely no sense to factor that into the average especially since they tossed it out in the earlier advisory. Automated Dvorak measurements need to be discontinued.

[aspen]

60kt. I don't normally support criticizing NHC decisions, but

The various satellite intensity estimates have a
wide range from 45-77 kt, and the consensus of the estimates is
that Danielle is not quite a hurricane yet.

Clearly the 45kt one is wrong and it makes absolutely no sense to factor that into the average especially since they tossed it out in the earlier advisory. Automated Dvorak measurements need to be discontinued.

ADT is usually pretty good…except when you’re dealing with high latitude systems. Even the manual Dvorak fix was better, and those are infamous for sometimes being awful.

[wxman57]

I think the NHC will jump to hurricane status next advisory. That 4.5 reading might decide it.

That Dvorak 4.5 was available before they issued the advisory at 09Z. Why would they not upgrade a system with an eye to a hurricane? Being "conservative"? It's a hurricane now, no doubt. May be a major hurricane later today, though it's only predicted to reach 70 kts in the next 24 hours. I think it's 70 kts now. Falling farther behind the power curve...

[Iceresistance]

Will be upgraded to a hurricane later today

 https://twitter.com/MJVentrice/status/1565653396329320450

[tolakram]

Floater on it.

https://weather.cod.edu/satrad/?parms=meso-meso2-02-200-0-100-1&checked=map&colorbar=undefined

SLIDER version
https://rammb-slider.cira.colostate.edu/?sat=goes-16&sec=mesoscale_02&x=954&y=981&z=2&angle=0&im=12&ts=1&st=0&et=0&speed=130&motion=loop&maps%5Bborders%5D=white&lat=0&p%5B0%5D=band_02&opacity%5B0%5D=1&pause=0&slider=-1&hide_controls=0&mouse_draw=0&follow_feature=0&follow_hide=0&s=rammb-slider&draw_color=FFD700&draw_width=6

[cycloneye]

Hurricane on next advisory.

AL, 05, 2022090212, , BEST, 0, 380N, 432W, 65, 992, HU

https://ftp.nhc.noaa.gov/atcf/btk/bal052022.dat

[Hypercane_Kyle]

Best track is 65 knots.

Code: Select all

Hurricane DANIELLE
As of 12:00 UTC Sep 02, 2022:

Location: 38.0°N 43.2°W
Maximum Winds: 65 kt  Gusts: N/A
Minimum Central Pressure: 992 mb
Environmental Pressure: N/A
Radius of Circulation: N/A
Radius of Maximum wind: 15 nm
64 kt Wind Radii by Quadrant:

[TallyTracker]

Danielle is looking like more borderline Cat1/Cat2 with the deeper convection developing. There does appear to be a dry slot eroding the east side of the eye. Once that’s worked out later today, I expect a Cat 3 is not out of the question.

[aspen]

Danielle is looking like more borderline Cat1/Cat2 with the deeper convection developing. There does appear to be a dry slot eroding the east side of the eye. Once that’s worked out later today, I expect a Cat 3 is not out of the question.

The question is whether or not the NHC will even recognize Cat 3 Danielle as a Cat 3 without recon. They’ve already been way too conservative with it.

[Iceresistance]

Danielle is looking like more borderline Cat1/Cat2 with the deeper convection developing. There does appear to be a dry slot eroding the east side of the eye. Once that’s worked out later today, I expect a Cat 3 is not out of the question.

The question is whether or not the NHC will even recognize Cat 3 Danielle as a Cat 3 without recon. They’ve already been way too conservative with it.

They have done it before, but it must maintain a strong inner core with a clear eye for some period of time,and the satellite intensity estimates must also be consistent for a CAT 3 as well.

[Iceresistance]

ASCAT has clipped the eastern side of the system, there are a lot of 50 knot barbs near the CoC.

[kevin]

Now officially the first Atlantic hurricane of the season.

ZCZC MIATCDAT5 ALL
TTAA00 KNHC DDHHMM

Hurricane Danielle Discussion Number 6
NWS National Hurricane Center Miami FL AL052022
300 PM GMT Fri Sep 02 2022

Danielle has continued to strengthen this morning. A ragged eye is
evident in conventional satellite imagery, and deep convection
surrounds much of the northern and western portions of the
circulation. A recent ASCAT-B pass missed the center but caught the
eastern portion of the circulation. It showed winds up to 52 kt on
the inner edge of the swath and tropical-storm-force winds extending
outward up to 100 n mi in the northeastern quadrant of the cyclone.
The latest objective and subjective satellite estimates support
raising the initial intensity to 65 kt, which makes Danielle the
first Atlantic hurricane of the season.

Atmospheric and oceanic conditions appear generally favorable for
some additional strengthening during the next couple of days. The
hurricane will meander over 27C SSTs in an environment of light to
moderate deep-layer shear. Danielle is a higher-latitude storm, and
so there is the potential for some mid-level dry air entrainment
that could briefly disrupt the cyclone's organization. The latest
intensity guidance consensus still favors some additional
strengthening through Sunday. The official NHC forecast is similar
to the previous one and lies slightly above the model consensus.
After 72 h, weakening is expected to commence as Danielle gains
latitude and moves over cooler waters while it encounters more
deep-layer shear within the mid-latitude westerlies.

Although the 12-hr motion of Danielle has been an easterly drift,
the hurricane appears to have become nearly stationary this
morning. The cyclone will likely continue to meander over the
central Atlantic during the next couple of days under the influence
of a blocking high pressure ridge. This feature is forecast to
weaken by early next week, which should allow Danielle to begin
moving northeastward by 72 h and accelerate deeper into the
mid-latitudes on days 4-5. Once again, it appears Danielle will not
begin extratropical transition until beyond the end of the forecast
period. The NHC track forecast generally lies near the center of
the guidance envelope, close to the reliable consensus aids.


FORECAST POSITIONS AND MAX WINDS

INIT 02/1500Z 37.9N 43.3W 65 KT 75 MPH
12H 03/0000Z 38.0N 43.3W 70 KT 80 MPH
24H 03/1200Z 38.1N 43.5W 75 KT 85 MPH
36H 04/0000Z 38.1N 44.0W 80 KT 90 MPH
48H 04/1200Z 38.5N 44.4W 85 KT 100 MPH
60H 05/0000Z 38.9N 44.1W 85 KT 100 MPH
72H 05/1200Z 39.6N 43.1W 85 KT 100 MPH
96H 06/1200Z 41.0N 40.5W 80 KT 90 MPH
120H 07/1200Z 42.5N 36.4W 70 KT 80 MPH

$$
Forecaster Reinhart

NNNN

[Sciencerocks]

[Iceresistance]

She's a beauty!


https://s1.gifyu.com/images/42245940.gif