WPAC: DORA - Post-Tropical - Discussion

[zzzh]

05E.

[cycloneye]

Very bullish first forecast.

TROPICAL DEPRESSION FIVE-E FORECAST/ADVISORY NUMBER 1
NWS NATIONAL HURRICANE CENTER MIAMI FL EP052023
2100 UTC MON JUL 31 2023

NOTICE... LAND-BASED TROPICAL CYCLONE WATCHES AND WARNINGS ARE NO
LONGER INCLUDED IN THE TROPICAL CYCLONE FORECAST/ADVISORY...(TCM).
CURRENT LAND-BASED COASTAL WATCHES AND WARNINGS CAN BE FOUND IN THE
MOST RECENTLY ISSUED TROPICAL CYCLONE PUBLIC ADVISORY...(TCP).

TROPICAL DEPRESSION CENTER LOCATED NEAR 14.8N 104.4W AT 31/2100Z
POSITION ACCURATE WITHIN 30 NM

PRESENT MOVEMENT TOWARD THE WEST OR 280 DEGREES AT 12 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 1008 MB
MAX SUSTAINED WINDS 30 KT WITH GUSTS TO 40 KT.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

REPEAT...CENTER LOCATED NEAR 14.8N 104.4W AT 31/2100Z
AT 31/1800Z CENTER WAS LOCATED NEAR 14.6N 103.8W

FORECAST VALID 01/0600Z 15.5N 106.4W
MAX WIND 35 KT...GUSTS 45 KT.
34 KT... 30NE 0SE 0SW 0NW.

FORECAST VALID 01/1800Z 15.8N 109.0W
MAX WIND 40 KT...GUSTS 50 KT.
34 KT... 30NE 0SE 0SW 30NW.

FORECAST VALID 02/0600Z 15.5N 111.7W
MAX WIND 50 KT...GUSTS 60 KT.
50 KT... 20NE 0SE 0SW 0NW.
34 KT... 40NE 30SE 30SW 40NW.

FORECAST VALID 02/1800Z 15.1N 114.3W
MAX WIND 65 KT...GUSTS 80 KT.
64 KT... 10NE 0SE 0SW 0NW.
50 KT... 30NE 20SE 10SW 20NW.
34 KT... 40NE 30SE 30SW 50NW.

FORECAST VALID 03/0600Z 14.7N 116.7W
MAX WIND 75 KT...GUSTS 90 KT.
50 KT... 30NE 20SE 20SW 30NW.
34 KT... 50NE 50SE 40SW 60NW.

FORECAST VALID 03/1800Z 14.3N 119.3W
MAX WIND 85 KT...GUSTS 105 KT.
50 KT... 40NE 30SE 30SW 40NW.
34 KT... 60NE 50SE 50SW 60NW.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 100 NM
ON DAY 4 AND 125 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY

OUTLOOK VALID 04/1800Z 13.3N 125.1W
MAX WIND 90 KT...GUSTS 110 KT.

OUTLOOK VALID 05/1800Z 12.7N 130.9W
MAX WIND 90 KT...GUSTS 110 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 14.8N 104.4W

NEXT ADVISORY AT 01/0300Z

$$
FORECASTER PAPIN

Tropical Depression Five-E Discussion Number 1
NWS National Hurricane Center Miami FL EP052023
400 PM CDT Mon Jul 31 2023

Through this morning and afternoon, the system we have been
monitoring several hundred miles offshore to the south of the coast
of Mexico has improved in organization on satellite imagery, with
plenty of curved convective bands along its northern semicircle. A
couple of bulls-eye ASCAT passes earlier this afternoon indicated
that a closed circulation had formed at the surface, with believable
25-30 kt winds on its northern flank. We also received a subjective
Dvorak intensity estimate of T2.0/30-kt from TAFB this afternoon.
The aforementioned data supports initiating advisories on the system
as a tropical depression, with maximum sustained winds of 30 kt.

The initial motion of the depression is north of due west at 280/12
kt. A prominent mid-level subtropical ridge is located poleward of
the cyclone and is expected to move westward with the system
throughout the forecast period. The orientation of the ridge ahead
of the system may even result in a west-southwestward motion by the
middle to latter part of this week. The track guidance is in fairly
good agreement, especially for a system that has only recently
formed, though some speed differences exist towards the end of the
forecast period. The initial NHC track forecast has opted to remain
close to the reliable consensus aids, roughly in between the faster
HCCA and slower TVCE guidance.

Environmental conditions appear quite favorable for intensification
over the next few days. Both the GFS- and EC-based SHIPS guidance
shows deep-layer vertical wind shear remaining 10 kt or below
throughout the forecast period as sea-surface temperatures
underneath the system remain above 28 C for the next 3 days. While
there will likely be some mid-level dry air lurking near the system
during this time-span, this may not harm the cyclone as much as
just keeping its convective core small. In fact, most of the
hurricane-regional models show the system significantly intensifying
as a small tropical cyclone during the forecast period. The NHC
intensity forecast follows this evolution, with significant
intensification expected, especially between 36-72 h after the
system has an opportunity to develop an inner core that takes better
advantage of the favorable conditions. A period of rapid
intensification during this time frame is also possible. This
initial intensity forecast is in best agreement with the SHIPS
guidance this cycle, and is roughly a split between the higher
HWRF/HMON and lower HAFS-A/B runs.


FORECAST POSITIONS AND MAX WINDS

INIT 31/2100Z 14.8N 104.4W 30 KT 35 MPH
12H 01/0600Z 15.5N 106.4W 35 KT 40 MPH
24H 01/1800Z 15.8N 109.0W 40 KT 45 MPH
36H 02/0600Z 15.5N 111.7W 50 KT 60 MPH
48H 02/1800Z 15.1N 114.3W 65 KT 75 MPH
60H 03/0600Z 14.7N 116.7W 75 KT 85 MPH
72H 03/1800Z 14.3N 119.3W 85 KT 100 MPH
96H 04/1800Z 13.3N 125.1W 90 KT 105 MPH
120H 05/1800Z 12.7N 130.9W 90 KT 105 MPH

$$
Forecaster Papin

[Sciencerocks]

[ElectricStorm]

I agree with the NHC's bullishness here. I think this will likely become a nice long-tracking major. Should produce some good ACE

[Kingarabian]

The only thing I think that could hold back intensity is if the STR keeps the lower level easterlies stronger than normal.

[Ntxw]

Should be a fun one to track. Maybe we'll get some great views out to sea. Maybe something like a Hector 18.

[Yellow Evan]

Nice curved band structure is promising for intensification prospects.

[cycloneye]

Should be a fun one to track. Maybe we'll get some great views out to sea. Maybe something like a Hector 18.

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

I liked the classic look of powerful Hurricane Marie of 2014. Hopefully we have great images from Dora.

[Ntxw]

Should be a fun one to track. Maybe we'll get some great views out to sea. Maybe something like a Hector 18.

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

I liked the classic look of powerful Hurricane Marie of 2014. Hopefully we have great images from Dora.

Definitely! The system behind this one has the more type track that Marie had, should it form. Two active systems potentially.

[Yellow Evan]

18z GFS comes in stronger with less shear and in line with ECMWF and consistent with the intraseasonal state. I also like that the GFS no longer flips the shear westerly in the CPAC. However, small systems like this can be fickle to any increases in shear especially below the outflow layer. Ceiling for this is a classic ultra long tracked hurricane, which would be very fun to track.

[Yellow Evan]

Should be a fun one to track. Maybe we'll get some great views out to sea. Maybe something like a Hector 18.

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

I liked the classic look of powerful Hurricane Marie of 2014. Hopefully we have great images from Dora.

I don’t think Dora gets to that magnitude and definitely will have a different structure to Marie. The one behind it on the other hand…

[Ntxw]

Should be a fun one to track. Maybe we'll get some great views out to sea. Maybe something like a Hector 18.

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

I liked the classic look of powerful Hurricane Marie of 2014. Hopefully we have great images from Dora.

I don’t think Dora gets to that magnitude and definitely will have a different structure to Marie. The one behind it on the other hand…

Yeah I agree, this one should remain compact you get that super long track, maybe cat 3 cat 4 30+ ACE look. The one behind for sure coming out of CA/SA now, would require some RI for that one once it gets near/south of Socorro isle.

[cycloneye]

EP, 05, 2023080100, , BEST, 0, 153N, 1047W, 30, 1008, TD

[Yellow Evan]

TXPZ21 KNES 010017
TCSENP

A. 05E (NONAME)

B. 01/0000Z

C. 15.5N

D. 104.6W

E. THREE/GOES-W

F. T2.0/2.0

G. IR/EIR/VIS/AMSR2

H. REMARKS...3.5/10 BANDING RESULTS IN A DT OF 2.0. MET IS 1.5 AND PT
IS 2.0. THE FT IS BASED ON THE PT BECAUSE THE BANDING IS NOT CLEAR-CUT.

I. ADDL POSITIONS

31/1954Z 15.2N 103.6W AMSR2


...CLARK

[Yellow Evan]

* GFS version *
* EAST PACIFIC 2023 SHIPS INTENSITY FORECAST *
* IR SAT DATA AVAILABLE, OHC AVAILABLE *
* FIVE EP052023 08/01/23 00 UTC *

TIME (HR) 0 6 12 18 24 36 48 60 72 84 96 108 120 132 144 156 168
V (KT) NO LAND 30 34 38 44 49 58 70 78 85 90 93 96 95 97 93 92 90
V (KT) LAND 30 34 38 44 49 58 70 78 85 90 93 96 95 97 93 92 90
V (KT) LGEM 30 33 36 40 44 53 62 71 80 90 97 99 99 97 94 91 89
Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP

SHEAR (KT) 9 11 10 5 1 9 9 9 6 5 9 6 4 5 9 9 4
SHEAR ADJ (KT) -1 -2 -4 -7 -2 0 -2 0 -2 2 1 1 4 0 -2 0 2
SHEAR DIR 73 72 88 123 101 13 25 45 48 54 62 115 152 135 114 125 137
SST (C) 30.3 30.5 29.8 29.7 29.4 29.1 28.9 28.4 28.4 28.1 27.3 27.2 26.7 26.6 27.0 27.0 26.5
POT. INT. (KT) 169 171 164 163 160 157 154 150 150 147 139 137 132 130 134 135 130
200 MB T (C) -51.1 -51.2 -51.3 -51.2 -50.9 -51.1 -50.8 -51.3 -51.0 -51.2 -51.3 -52.0 -51.8 -52.5 -52.3 -52.5 -52.1
200 MB VXT (C) 0.1 0.1 0.1 0.2 0.4 0.5 0.5 0.6 0.5 0.5 0.6 0.8 0.4 0.3 0.2 0.1 -0.1
TH_E DEV (C) 10 9 8 9 8 7 6 6 6 5 4 4 4 3 3 2 2
700-500 MB RH 69 68 67 64 62 62 64 64 66 67 67 69 64 66 65 63 56
MODEL VTX (KT) 8 9 10 11 11 12 14 15 17 19 20 21 20 22 20 19 18
850 MB ENV VOR 17 6 -1 6 2 8 12 14 44 62 78 78 72 87 83 77 68
200 MB DIV 16 28 20 21 4 -14 9 -8 32 9 30 16 27 -11 -29 -26 -2
700-850 TADV -4 -4 0 0 -3 -3 0 -1 3 0 0 1 0 -3 -1 1 2
LAND (KM) 367 405 446 540 651 872 1020 1212 1444 1689 1955 2196 2409 2321 2124 1883 1600
LAT (DEG N) 15.3 15.7 16.0 16.0 15.9 15.5 15.1 14.7 14.3 13.8 13.3 13.0 12.9 xx.x xx.x xx.x xx.x
LONG(DEG W) 104.7 106.0 107.3 108.6 109.9 112.7 115.1 117.6 120.3 123.2 126.2 129.1 131.8 xxx.x xxx.x xxx.x xxx.x
STM SPEED (KT) 12 13 13 12 13 13 12 13 14 14 15 14 12 11 11 12 12
HEAT CONTENT 46 47 33 29 27 22 15 13 14 11 4 3 2 5 8 9 2

FORECAST TRACK FROM OFCI INITIAL HEADING/SPEED (DEG/KT):290/ 11 CX,CY: -9/ 4
T-12 MAX WIND: 25 PRESSURE OF STEERING LEVEL (MB): 568 (MEAN=588)
GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 13.8 (MEAN=14.5)
% GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 79.0 (MEAN=65.0)
PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 28.9

INDIVIDUAL CONTRIBUTIONS TO INTENSITY CHANGE
6 12 18 24 36 48 60 72 84 96 108 120 132 144 156 168
--------------------------------------------------------------------------------------------
SAMPLE MEAN CHANGE 0. 1. 1. 1. 1. 2. 2. 1. 1. -0. -1. -1. -2. -3. -3. -4.
SST POTENTIAL -0. -1. -0. 1. 6. 13. 21. 28. 33. 37. 41. 44. 46. 47. 48. 48.
VERTICAL SHEAR MAG 1. 1. 2. 4. 5. 5. 5. 5. 6. 5. 6. 7. 8. 9. 9. 11.
VERTICAL SHEAR ADJ 0. 0. 1. 2. 2. 2. 2. 2. 1. 1. 0. 0. 0. 0. 0. 0.
VERTICAL SHEAR DIR 0. 1. 1. 2. 2. 3. 4. 5. 6. 6. 6. 5. 4. 2. 1. 1.
PERSISTENCE 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1.
200/250 MB TEMP. -0. -0. -1. -1. -1. -1. -1. -1. -1. -1. -1. -0. 0. 1. 1. -1.
THETA_E EXCESS 0. 1. 1. 2. 3. 3. 3. 3. 2. 2. 1. 0. -0. -1. -1. -1.
700-500 MB RH 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 1.
MODEL VTX TENDENCY 0. 1. 3. 3. 3. 6. 9. 12. 15. 17. 17. 13. 15. 11. 10. 8.
850 MB ENV VORTICITY -0. -0. -0. -0. -0. -0. 0. 0. 0. 0. -0. -0. -0. -0. -0. -0.
200 MB DIVERGENCE -0. -0. -0. -0. -0. -1. -1. -2. -2. -2. -2. -1. -0. 0. 0. 0.
850-700 T ADVEC 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. -0. -0. -0. -0. -0.
ZONAL STORM MOTION 0. -0. -0. -0. 0. 0. 0. -0. -0. -0. -0. -0. -0. -0. -1. -1.
STEERING LEVEL PRES -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0.
DAYS FROM CLIM. PEAK 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 1. 1.
GOES PREDICTORS 1. 1. 2. 2. 1. 1. 0. 0. -0. -1. -1. -0. -1. -1. -1. -2.
OCEAN HEAT CONTENT -0. -0. -0. -0. -0. 0. 0. 0. -0. -0. -0. -0. -0. -0. 0. 0.
RI POTENTIAL 1. 2. 3. 4. 6. 5. 3. 1. -1. -2. -2. -3. -3. -3. -2. -2.
--------------------------------------------------------------------------------------------
TOTAL CHANGE 4. 8. 14. 19. 28. 40. 48. 55. 60. 63. 66. 65. 67. 63. 62. 60.

CURRENT MAX WIND (KT): 30. LAT, LON: 15.3 104.7

** 2023 E. PACIFIC RI INDEX EP052023 FIVE 08/01/23 00 UTC **
(SHIPS-RII PREDICTOR TABLE for 30 KT OR MORE MAXIMUM WIND INCREASE IN NEXT 24-h)

Predictor Value RI Predictor Range Scaled Value(0-1) % Contribution
POT = MPI-VMAX (KT) : 135.6 36.9 to 148.5 0.88 11.1
12 HR PERSISTENCE (KT) : 5.0 -22.0 to 44.0 0.41 4.5
MULTI-LAYER SHEAR (KT) : 13.8 30.9 to 7.7 0.74 6.3
BL DRY-AIR FLUX (W/M2) : 115.2 816.2 to -81.4 0.78 -7.6
D200 (10**7s-1) : 17.8 -33.0 to 159.5 0.26 2.0
MAXIMUM WIND (KT) : 30.0 22.5 to 132.0 0.21 1.6
STD DEV OF IR BR TEMP : 13.8 37.8 to 2.1 0.67 4.1
HEAT CONTENT (KJ/CM2) : 36.4 2.7 to 103.4 0.33 1.2
%area of TPW <45 mm upshear : 0.0 49.8 to 0.0 1.00 2.3
2nd PC OF IR BR TEMP : -0.3 2.2 to -2.3 0.55 0.1

SHIPS Prob RI for 20kt/ 12hr RI threshold= 13% is 2.1 times climatological mean ( 6.3%)
SHIPS Prob RI for 25kt/ 24hr RI threshold= 36% is 2.9 times climatological mean (12.5%)
SHIPS Prob RI for 30kt/ 24hr RI threshold= 26% is 3.0 times climatological mean ( 8.6%)
SHIPS Prob RI for 35kt/ 24hr RI threshold= 19% is 3.0 times climatological mean ( 6.2%)
SHIPS Prob RI for 40kt/ 24hr RI threshold= 0% is 0.0 times climatological mean ( 4.2%)
SHIPS Prob RI for 45kt/ 36hr RI threshold= 24% is 3.6 times climatological mean ( 6.7%)
SHIPS Prob RI for 55kt/ 48hr RI threshold= 25% is 4.2 times climatological mean ( 5.9%)
SHIPS Prob RI for 65kt/ 72hr RI threshold= 36% is 7.6 times climatological mean ( 4.7%)

Matrix of RI probabilities
------------------------------------------------------------------------------
RI (kt / h) | 20/12 | 25/24 | 30/24 | 35/24 | 40/24 | 45/36 | 55/48 |65/72
------------------------------------------------------------------------------
SHIPS-RII: 13.0% 36.0% 25.6% 18.6% 0.0% 24.1% 24.6% 35.6%
Logistic: 4.9% 33.7% 18.4% 10.3% 9.6% 19.6% 22.3% 22.6%
Bayesian: 0.0% 10.1% 1.0% 0.3% 0.5% 1.9% 1.0% 0.6%
Consensus: 6.0% 26.6% 15.0% 9.7% 3.4% 15.2% 16.0% 19.6%
DTOPS: 3.0% 29.0% 14.0% 9.0% 6.0% 23.0% 43.0% 85.0%

## ANNULAR HURRICANE INDEX (AHI) EP052023 FIVE 08/01/23 00 UTC ##
## STORM NOT ANNULAR, SCREENING STEP FAILED, NPASS=3 NFAIL=4 ##
## AHI= 0 (AHI OF 100 IS BEST FIT TO ANN. STRUC., 1 IS MARGINAL, 0 IS NOT ANNULAR) ##

[Sciencerocks]

[cycloneye]

Peak intensity up to 95kt.

Tropical Depression Five-E Discussion Number 2
NWS National Hurricane Center Miami FL EP052023
1000 PM CDT Mon Jul 31 2023

Tropical Depression Five-E is starting to become a little better
organized this evening. Microwave AMSR and SSMIS passes showed that
the center of the system has banding features over the northern and
eastern side, with deep convection bursting from time to time.
Subjective Dvorak intensity estimates from TAFB and SAB were both
T2.0/30-kt on this advisory cycle. Given these estimates, the
initial intensity remains at 30 kt.

The initial motion of the depression is 290/12 kt. A mid-level
subtropical ridge is located to the north of the system and is
expected to continue to steer the cyclone generally westward. The
ridge may strengthen some towards the end of the week, causing a
south of west motion. The track guidance is fairly tightly
clustered, and the forward speed of the corrected consensus
guidance, HCCA, is now closer to the rest of the forecast aids this
cycle. The NHC track is very similar to the previous forecast, with
a slightly faster forward motion.

The system is in an environment that appears favorable for
intensification over the next few days. Vertical wind shear will
remain low throughout the forecast period with warm sea-surface
temperatures during the next several days. The cyclone is forecast
to quickly intensify with a relatively small convective core.
Intensity guidance has increased this cycle with SHIPS, HCCA, and
the hurricane regional models showing significant strengthening
over the next 24-72 hours. While a period of rapid intensification
is becoming more likely during the next few days, it is difficult
to pin down an exact time frame of when that may occur right now.
The intensity forecast was raised from the previous advisory to
account for some of the higher guidance this cycle, but still lies
below the HCCA and most of the hurricane regional models.


FORECAST POSITIONS AND MAX WINDS

INIT 01/0300Z 15.5N 105.3W 30 KT 35 MPH
12H 01/1200Z 15.9N 107.3W 40 KT 45 MPH
24H 02/0000Z 15.9N 110.0W 50 KT 60 MPH
36H 02/1200Z 15.6N 112.7W 65 KT 75 MPH
48H 03/0000Z 15.2N 115.4W 75 KT 85 MPH
60H 03/1200Z 14.7N 118.1W 90 KT 105 MPH
72H 04/0000Z 14.2N 121.0W 95 KT 110 MPH
96H 05/0000Z 13.3N 126.8W 90 KT 105 MPH
120H 06/0000Z 12.9N 132.7W 85 KT 100 MPH

$$
Forecaster Kelly/Blake

[lilbump3000]

Advisory #2

https://www.youtube.com/shorts/gE8RHD5rdEQ

[Yellow Evan]

Hopefully the NHC doesn’t do what it tends to do - show weakening in low shear environments in accordance with the statistical guidance.

[Yellow Evan]

ASCAT came in with 32 knots. Supports 35 when considering the low bias of the instrument.