WPAC: DORA - Post-Tropical - Discussion

[Kingarabian]

CMC is just so bad right now. Initializes this as a 1012 mb low.

[lilbump3000]

[cycloneye]

Looks great with that superb outflow.

[Sciencerocks]

[Yellow Evan]

CMC is just so bad right now. Initializes this as a 1012 mb low.

ECMWF little better - init at 1008 mbar.

[Yellow Evan]

TXPZ21 KNES 011818
TCSENP

A. 05E (DORA)

B. 01/1801Z

C. 16.1N

D. 109.4W

E. THREE/GOES-E

F. T3.0/3.0

G. IR/EIR/VIS

H. REMARKS...6/10 BANDING YIELDS A DT OF 3.0. THE MET IS 3.0 BASED ON
A 24 HR RAPID DEVELOPING TREND. THE PT IS ALSO 3.0. THE FT IS BASED ON
THE DT.

I. ADDL POSITIONS

NIL


...GATLING

[cycloneye]

Up to 55kt.

EP, 05, 2023080118, , BEST, 0, 161N, 1094W, 55, 998, TS

[Sciencerocks]

[Yellow Evan]

* GFS version *
* EAST PACIFIC 2023 SHIPS INTENSITY FORECAST *
* IR SAT DATA AVAILABLE, OHC AVAILABLE *
* DORA EP052023 08/01/23 18 UTC *

TIME (HR) 0 6 12 18 24 36 48 60 72 84 96 108 120 132 144 156 168
V (KT) NO LAND 55 63 70 77 82 90 95 95 91 90 91 91 91 89 89 87 85
V (KT) LAND 55 63 70 77 82 90 95 95 91 90 91 91 91 89 89 87 85
V (KT) LGEM 55 64 72 79 85 95 101 101 99 97 99 98 97 95 90 83 78
Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP

SHEAR (KT) 6 5 1 4 6 12 15 13 11 9 3 3 4 6 5 4 2
SHEAR ADJ (KT) -6 -5 3 1 -1 -3 -4 -3 0 -2 0 4 2 3 5 7 9
SHEAR DIR 130 170 83 54 34 71 74 89 83 103 181 152 21 106 161 183 258
SST (C) 29.9 29.7 29.4 29.2 29.1 28.9 28.3 27.8 26.7 27.6 26.9 26.8 27.3 26.9 27.0 27.1 26.9
POT. INT. (KT) 165 163 160 158 157 155 149 144 133 142 135 133 139 135 136 137 135
200 MB T (C) -51.0 -50.9 -51.0 -51.1 -51.0 -51.2 -51.1 -51.2 -51.6 -51.7 -52.3 -52.0 -52.4 -52.1 -52.5 -52.5 -52.7
200 MB VXT (C) 0.2 0.3 0.4 0.4 0.3 0.5 0.6 0.8 0.9 0.8 0.6 0.4 0.3 0.2 0.1 -0.1 -0.3
TH_E DEV (C) 8 8 8 7 6 6 5 5 4 4 4 4 4 4 4 4 4
700-500 MB RH 63 61 59 59 58 57 58 59 59 60 60 62 64 61 53 47 46
MODEL VTX (KT) 10 11 11 13 13 14 16 16 16 17 19 19 19 17 17 13 12
850 MB ENV VOR 4 6 6 9 15 24 40 60 74 82 68 67 71 80 84 74 34
200 MB DIV 9 2 -1 -6 8 -1 -6 -19 -14 41 0 16 -19 -22 -23 -18 -28
700-850 TADV 4 0 -4 -2 0 -1 0 0 -1 -1 0 -4 -4 -1 -1 -4 -4
LAND (KM) 594 717 803 866 948 1184 1455 1708 1988 2255 2418 2129 1883 1599 1279 1025 864
LAT (DEG N) 16.1 16.1 16.0 15.9 15.8 15.2 14.6 14.1 13.5 13.1 12.9 12.6 12.2 xx.x xx.x xx.x xx.x
LONG(DEG W) 109.4 110.8 112.2 113.6 115.0 117.8 120.8 123.8 126.8 130.0 133.2 136.2 138.9 xxx.x xxx.x xxx.x xxx.x
STM SPEED (KT) 13 13 13 13 14 14 15 15 15 16 15 14 14 15 16 16 16
HEAT CONTENT 30 29 23 18 17 17 13 12 2 6 4 7 21 5 5 5 3

FORECAST TRACK FROM OFCI INITIAL HEADING/SPEED (DEG/KT):280/ 14 CX,CY: -13/ 2
T-12 MAX WIND: 35 PRESSURE OF STEERING LEVEL (MB): 457 (MEAN=588)
GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 10.5 (MEAN=14.5)
% GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 96.0 (MEAN=65.0)
PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 42.1

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 1. 2. 4. 5. 8. 11. 15. 18. 20. 22. 24. 25. 25. 26. 26. 25.
VERTICAL SHEAR MAG 0. 1. 2. 3. 3. 3. 2. 1. 1. 3. 4. 6. 7. 8. 10. 12.
VERTICAL SHEAR ADJ 0. 0. 0. 1. 2. 2. 2. 2. 1. 1. 0. 0. 0. 0. 0. -0.
VERTICAL SHEAR DIR -0. 0. 1. 1. 2. 4. 5. 6. 7. 6. 5. 4. 3. 2. 1. 0.
PERSISTENCE 4. 6. 7. 7. 6. 5. 4. 3. 2. 2. 2. 2. 2. 2. 2. 2.
200/250 MB TEMP. -0. -0. -1. -1. -1. -1. -1. -1. -1. -0. 0. 1. 2. 2. 1. 0.
THETA_E EXCESS 0. 0. 1. 1. 1. 1. 0. -0. -1. -1. -1. -1. -2. -2. -2. -2.
700-500 MB RH -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. 0. 0. 0. -0.
MODEL VTX TENDENCY 0. 0. 2. 3. 3. 6. 7. 8. 9. 11. 11. 9. 7. 6. 3. 1.
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. -1. -1. -2. -3. -3. -3. -2. -2. -1. 0. 0. 1.
850-700 T ADVEC -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -1.
ZONAL STORM MOTION 0. -0. -0. -0. 0. 0. 0. -0. -0. -0. -1. -0. -1. -1. -2. -2.
STEERING LEVEL PRES -0. -0. -1. -1. -1. -2. -2. -2. -2. -3. -3. -3. -3. -3. -2. -1.
DAYS FROM CLIM. PEAK 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 1. 1.
GOES PREDICTORS 1. 2. 2. 2. 2. 2. 2. 2. 2. 2. 3. 3. 3. 2. 2. 2.
OCEAN HEAT CONTENT -0. -0. -0. -0. -0. 0. 0. -0. 0. 0. 0. 0. 0. 1. 1. 1.
RI POTENTIAL 1. 3. 5. 7. 11. 10. 5. 1. -1. -3. -5. -6. -6. -6. -6. -5.
--------------------------------------------------------------------------------------------
TOTAL CHANGE 8. 15. 22. 27. 35. 40. 40. 36. 35. 36. 36. 36. 34. 34. 32. 30.

CURRENT MAX WIND (KT): 55. LAT, LON: 16.1 109.4

** 2023 E. PACIFIC RI INDEX EP052023 DORA 08/01/23 18 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) : 105.9 36.9 to 148.5 0.62 18.9
12 HR PERSISTENCE (KT) : 20.0 -22.0 to 44.0 0.64 16.8
MULTI-LAYER SHEAR (KT) : 13.9 30.9 to 7.7 0.73 15.2
BL DRY-AIR FLUX (W/M2) : 305.8 816.2 to -81.4 0.57 -13.4
D200 (10**7s-1) : 2.4 -33.0 to 159.5 0.18 3.4
MAXIMUM WIND (KT) : 55.0 22.5 to 132.0 0.93 16.5
STD DEV OF IR BR TEMP : 10.5 37.8 to 2.1 0.76 11.2
HEAT CONTENT (KJ/CM2) : 23.4 2.7 to 103.4 0.21 1.8
%area of TPW <45 mm upshear : 0.0 49.8 to 0.0 1.00 5.6
2nd PC OF IR BR TEMP : -0.6 2.2 to -2.3 0.62 0.2

SHIPS Prob RI for 20kt/ 12hr RI threshold= 59% is 9.3 times climatological mean ( 6.3%)
SHIPS Prob RI for 25kt/ 24hr RI threshold= 77% is 5.9 times climatological mean (12.5%)
SHIPS Prob RI for 30kt/ 24hr RI threshold= 76% is 9.0 times climatological mean ( 8.6%)
SHIPS Prob RI for 35kt/ 24hr RI threshold= 74% is 12.3 times climatological mean ( 6.2%)
SHIPS Prob RI for 40kt/ 24hr RI threshold= 54% is 12.9 times climatological mean ( 4.2%)
SHIPS Prob RI for 45kt/ 36hr RI threshold= 68% is 10.2 times climatological mean ( 6.7%)
SHIPS Prob RI for 55kt/ 48hr RI threshold= 46% is 7.8 times climatological mean ( 5.9%)
SHIPS Prob RI for 65kt/ 72hr RI threshold= 11% is 2.3 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: 58.6% 77.3% 76.2% 74.1% 54.3% 68.1% 45.9% 10.8%
Logistic: 53.8% 62.6% 52.9% 39.6% 28.7% 15.5% 5.1% 8.6%
Bayesian: 19.0% 50.8% 6.8% 3.6% 11.5% 4.0% 0.5% 0.0%
Consensus: 43.8% 63.6% 45.3% 39.1% 31.5% 29.2% 17.1% 6.5%
DTOPS: 59.0% 79.0% 75.0% 73.0% 59.0% 74.0% 56.0% 23.0%

## ANNULAR HURRICANE INDEX (AHI) EP052023 DORA 08/01/23 18 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) ##

[cycloneye]

Tropical Storm Dora Discussion Number 5
NWS National Hurricane Center Miami FL EP052023
300 PM MDT Tue Aug 01 2023

Dora continues to become better organized this afternoon. The storm
has maintained a well-defined curved band in its eastern semicircle
as a cold central dense overcast has persisted near the center.
Subjective intensity estimates from TAFB and SAB remained unchanged
this afternoon, but we also received an ASCAT-B pass at 1728 UTC
which showed a peak-wind retrieval of 51 kt. Due to the very small
size of the wind field seen from this scatterometer pass, it is
quite possible this value may be undersampling the storm's maximum
sustained winds. Therefore, the intensity was nudged upward to 55 kt
for this advisory.

Dora might be starting to make a gradual leftward turn, with the
most recent estimated motion due west at 270/14 kt. There is not a
ton new to report for the track forecast this afternoon, with a
large mid-level ridge expected to build northwestward relative to
Dora. This evolution should result in Dora turning
west-southwestward beginning tomorrow and continuing through the end
of the forecast period. The track guidance remains in fairly good
agreement, and the latest NHC track forecast is very similar to the
previous one, in best agreement with the HFIP corrected consensus
approach (HCCA).

So far, Dora shows little signs of pausing its intensification rate
this afternoon. Vertical wind shear remains very low (at or under 5
kt) and sea-surface temperatures (SSTs) remain very warm (29 C or
warmer). Assuming dry air does not disrupt the small inner core that
has formed today, rapid intensification (RI) appears likely for the
next day or so. This expectation is supported by SHIPS-RII guidance
from both the ECMWF and GFS, which show a 74 percent chance of a 35
kt increase in intensity over the next 24 hours. These values are
12-13 times above its climatological mean. Therefore, the latest NHC
intensity forecast shows this rate of intensification over the next
day, ultimately peaking Dora as a 110-kt category 3 hurricane in 48
hours. This intensity forecast is not that far off the most recent
HCCA intensity aid but is still a bit lower than the latest HAFS-A/B
guidance. Thereafter, SSTs begin to drop down to 27 C and a modest
increase in easterly shear may lead to some gradual weakening.
Hard-to-predict inner core changes during this period may also
result in some intensity fluctuations, possibly larger than shown
here given how small Dora is forecast to remain.


FORECAST POSITIONS AND MAX WINDS

INIT 01/2100Z 16.1N 110.1W 55 KT 65 MPH
12H 02/0600Z 16.1N 112.3W 70 KT 80 MPH
24H 02/1800Z 15.9N 115.1W 90 KT 105 MPH
36H 03/0600Z 15.4N 117.9W 105 KT 120 MPH
48H 03/1800Z 15.0N 121.0W 110 KT 125 MPH
60H 04/0600Z 14.5N 124.1W 105 KT 120 MPH
72H 04/1800Z 13.9N 127.1W 100 KT 115 MPH
96H 05/1800Z 13.2N 133.5W 95 KT 110 MPH
120H 06/1800Z 12.5N 139.5W 90 KT 105 MPH

$$
Forecaster Papin

[Kingarabian]

Looks like it has taken on some dry air.

[Sciencerocks]

[Hurricane2022]

Dora is ready to explode.

[Yellow Evan]

 https://twitter.com/andyhazelton/status/1686532508274638848

[cycloneye]

TXPZ21 KNES 020014
TCSENP

A. 05E (DORA)

B. 02/0000Z

C. 16.3N

D. 110.6W

E. THREE/GOES-W

F. T3.5/3.5

G. IR/EIR/VIS/AMSR2

H. REMARKS...7.5/10 BANDING RESULTS IN A DT OF 3.5. THE MET IS 3.0 AND
THE PT IS 3.5. THE FT IS BASED ON THE DT.

I. ADDL POSITIONS

01/2037Z 16.2N 110.0W AMSR2


...BROWN

[Yellow Evan]

Dvorak agencies are going to have a nightmare with this in the short term unless they use embedded center either IR or visible.

[Yellow Evan]

 https://twitter.com/andyhazelton/status/1686536834657239043

[cycloneye]

We got Hurricane Dora.

EP, 05, 2023080200, , BEST, 0, 162N, 1108W, 65, 994, HU

https://ftp.nhc.noaa.gov/atcf/btk/bep052023.dat

[Ntxw]

Storms that move SW initially can have that east/northerly shear look until they move w or nw. Regardless, Hurricane Dora now.

Not the back to back cat4s like some other seasons but 4 named and 4 hurricanes so far.

[aspen]

Dvorak agencies are going to have a nightmare with this in the short term unless they use embedded center either IR or visible.

I’m dreading the bad Dvorak fixes we’re going to get with a tiny RI’ing Hurricane Dora lol.