EPAC: INVEST 93E - Discussion

[Subtrop]

EP, 93, 2023070612, , BEST, 0, 130N, 1080W, 20, 1008, DB, 34, NEQ, 0, 0, 0, 0, 1010, 130, 0, 0, 0, E, 0, , 0, 0, INVEST, S,

https://ftp.nhc.noaa.gov/atcf/btk/bep932023.dat

[Sciencerocks]

[cycloneye]

Offshore of Southwestern Mexico (EP93):
A broad area of low pressure located several hundred miles south of
southwestern Mexico is producing disorganized showers and
thunderstorms. Environmental conditions are forecast to be
conducive for gradual development of this system, and a tropical
depression will likely form over the weekend while it moves
generally west-northwestward, away from the coast of mainland
Mexico.
* Formation chance through 48 hours...high...70 percent.
* Formation chance through 7 days...high...80 percent.

[ElectricStorm]

I think there's potential this can become another hurricane but I'm not sure it has enough time to become anything too strong, especially if it ends up being broad. Perhaps a Cat 1 but probably not much more than that.

[Kingarabian]

Models keep this as a baseline hurricane. Takes too long to organize and by the time it gets going it's running into cooler waters and easterly flow from that Nina high pressure system.

[Yellow Evan]

Models keep this as a baseline hurricane. Takes too long to organize and by the time it gets going it's running into cooler waters and easterly flow from that Nina high pressure system.

Said Mexican high that results in easterly shear is present regardless of a Niña or Nino fwiw. Just stronger and more eastward during a Niña. TCs this year will get sheared by the high at middle and deep layers just not to the same extent as the last 3.

[Sciencerocks]

[Yellow Evan]

ULAC is pretty far displaced to the north, resulting in stronger easterly flow. Mid level ridging is not in agreement with upper level ridging over the United States which is bound to impart shear over the system as well.

[cycloneye]

A broad area of low pressure located several hundred miles south of
southwestern Mexico is starting to show signs of organization.
Environmental conditions are forecast to be conducive for gradual
development of this system, and a tropical depression will likely
form during the next couple of days while it moves generally
west-northwestward, away from the coast of mainland Mexico.
* Formation chance through 48 hours...high...70 percent.
* Formation chance through 7 days...high...90 percent.

[cycloneye]

EP, 93, 2023070700, , BEST, 0, 126N, 1075W, 20, 1008, DB

[Kingarabian]

Models keep this as a baseline hurricane. Takes too long to organize and by the time it gets going it's running into cooler waters and easterly flow from that Nina high pressure system.

https://media.discordapp.net/attachments/733552978572869632/1126635321539448852/IMG_7935.png

Said Mexican high that results in easterly shear is present regardless of a Niña or Nino fwiw. Just stronger and more eastward during a Niña. TCs this year will get sheared by the high at middle and deep layers just not to the same extent as the last 3.

Yeah it's just more pronounced during non Nino years as those are more like to have a -PDO/-PMM which amplifies the effects of this high.

[Yellow Evan]

Offshore of Southwestern Mexico (EP93):
A broad area of low pressure located several hundred miles south of
southwestern Mexico is starting to show signs of organization.
Environmental conditions are forecast to be conducive for gradual
development of this system, and a tropical depression will likely
form during the next couple of days while it moves generally
west-northwestward, away from the coast of mainland Mexico.
* Formation chance through 48 hours...high...80 percent.
* Formation chance through 7 days...high...90 percent.

[Sciencerocks]

[cycloneye]

Offshore of Southwestern Mexico (EP93):
Showers and thunderstorms associated with a broad area of low
pressure located several hundred miles south-southwest of
Manzanillo, Mexico, are showing some signs of organization.
Environmental conditions are forecast to remain conducive
for additional development, and a tropical depression is likely to
form within the next day or so while the disturbance moves
generally west-northwestward, away from the coast of mainland
Mexico.
* Formation chance through 48 hours...high...90 percent.
* Formation chance through 7 days...high...90 percent.

[Kingarabian]

Models much weaker the past 2 runs.

[Yellow Evan]

* GFS version *
* EAST PACIFIC 2023 SHIPS INTENSITY FORECAST *
* IR SAT DATA AVAILABLE, OHC AVAILABLE *
* INVEST EP932023 07/07/23 12 UTC *

TIME (HR) 0 6 12 18 24 36 48 60 72 84 96 108 120 132 144 156 168
V (KT) NO LAND 20 22 26 30 33 41 47 52 54 50 45 37 31 25 21 19 16
V (KT) LAND 20 22 26 30 33 41 47 52 54 50 45 37 31 25 21 19 16
V (KT) LGEM 20 20 21 22 22 24 24 24 24 22 20 18 15 N/A N/A N/A N/A
Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP

SHEAR (KT) 17 12 13 18 16 17 17 13 10 7 6 9 9 8 11 13 18
SHEAR ADJ (KT) -1 2 4 7 4 2 4 1 3 6 4 4 1 1 -2 -1 -3
SHEAR DIR 54 38 41 40 45 57 66 68 59 89 78 95 163 186 229 239 229
SST (C) 28.4 28.3 28.2 28.2 28.3 27.8 27.2 26.5 25.3 24.4 22.6 21.5 21.2 20.4 20.6 21.5 21.9
POT. INT. (KT) 146 145 145 146 147 142 136 128 116 107 89 77 75 67 69 78 82
200 MB T (C) -51.8 -51.3 -50.9 -51.3 -51.5 -50.7 -51.1 -50.5 -50.7 -50.5 -50.7 -50.5 -50.8 -50.9 -51.0 -51.2 -51.4
200 MB VXT (C) 0.2 0.1 0.1 0.1 0.2 0.3 0.4 0.4 0.6 0.8 0.7 0.3 0.4 0.3 0.1 0.2 0.1
TH_E DEV (C) 4 4 4 4 3 2 1 0 0 0 0 0 0 0 0 0 0
700-500 MB RH 79 78 79 80 81 80 77 70 69 65 61 55 54 49 46 44 43
MODEL VTX (KT) 13 17 19 20 21 26 27 27 26 24 21 17 13 10 8 6 4
850 MB ENV VOR 16 26 32 42 53 73 94 114 116 97 88 78 68 74 44 6 -26
200 MB DIV 91 90 87 89 62 79 37 13 -16 -28 -3 -15 -12 0 -16 13 -6
700-850 TADV -4 -6 -5 -8 -7 -9 -8 -6 -2 0 2 3 7 14 21 26 19
LAND (KM) 622 594 582 579 606 704 719 759 853 915 1009 1085 1208 1400 1530 1648 1795
LAT (DEG N) 14.0 14.4 14.8 15.3 15.7 16.4 17.0 17.6 18.2 19.0 20.0 21.1 22.1 xx.x xx.x xx.x xx.x
LONG(DEG W) 107.1 107.2 107.7 108.4 109.2 110.9 112.8 114.6 116.5 118.4 120.5 122.8 125.2 xxx.x xxx.x xxx.x xxx.x
STM SPEED (KT) 5 5 7 9 9 9 10 9 10 10 11 12 13 14 15 14 12
HEAT CONTENT 12 11 10 11 14 7 4 1 0 0 0 0 0 0 0 0 0

FORECAST TRACK FROM TABM INITIAL HEADING/SPEED (DEG/KT): 40/ 6 CX,CY: 4/ 5
T-12 MAX WIND: 20 PRESSURE OF STEERING LEVEL (MB): 811 (MEAN=588)
GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 20.1 (MEAN=14.5)
% GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 43.0 (MEAN=65.0)
PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 16.7

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. 0. 5. 12. 19. 24. 27. 29. 29. 27. 24. 21. 18. 16.
VERTICAL SHEAR MAG 1. 2. 3. 4. 4. 2. -0. -2. -3. -3. -2. -2. -0. 0. 0. -0.
VERTICAL SHEAR ADJ 0. -0. -1. -1. -1. -2. -2. -2. -1. -1. -1. -0. -0. -0. -0. -0.
VERTICAL SHEAR DIR 0. 1. 1. 2. 3. 4. 5. 5. 5. 4. 3. 2. 2. 1. 1. 0.
PERSISTENCE -0. -0. -0. -1. -1. -1. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0.
200/250 MB TEMP. -0. -0. -1. -1. -2. -2. -2. -2. -2. -2. -1. -1. -1. -1. -1. -1.
THETA_E EXCESS -0. -0. -1. -1. -3. -5. -6. -8. -10. -11. -11. -11. -11. -11. -10. -10.
700-500 MB RH 0. 0. 1. 1. 2. 2. 2. 2. 2. 1. 1. 1. 0. 0. 0. 1.
MODEL VTX TENDENCY 1. 3. 5. 6. 9. 13. 16. 17. 14. 9. 3. -2. -4. -6. -7. -8.
850 MB ENV VORTICITY -0. -0. 0. 0. 0. 0. -0. -0. -0. -1. -1. -1. -1. -1. -1. -1.
200 MB DIVERGENCE 0. 0. 1. 1. 1. 1. 1. 1. 0. 0. -0. -0. -0. 0. 0. 0.
850-700 T ADVEC 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. -0. -0. 0. 1. 2.
ZONAL STORM MOTION -0. 0. 0. 0. -0. -1. -1. 0. 1. 1. 1. 1. 2. 2. 4. 5.
STEERING LEVEL PRES 0. 1. 1. 2. 3. 3. 4. 4. 5. 5. 6. 7. 6. 5. 4. 2.
DAYS FROM CLIM. PEAK -0. -0. -0. -0. -0. -0. -0. -1. -1. -2. -2. -2. -3. -3. -3. -4.
GOES PREDICTORS -0. 0. 0. 0. -1. -2. -4. -5. -5. -6. -7. -7. -8. -7. -6. -7.
OCEAN HEAT CONTENT 0. 0. 0. 0. 0. -0. -0. -0. 0. 0. 0. 0. 1. 2. 3. 4.
RI POTENTIAL 0. 1. 1. 1. 2. 1. 0. 0. -0. 0. 0. 0. 0. 0. 1. 0.
--------------------------------------------------------------------------------------------
TOTAL CHANGE 2. 6. 10. 13. 21. 27. 32. 34. 30. 25. 17. 11. 5. 1. -1. -4.

CURRENT MAX WIND (KT): 20. LAT, LON: 14.0 107.1

** 2023 E. PACIFIC RI INDEX EP932023 INVEST 07/07/23 12 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) : 125.8 36.9 to 148.5 0.80 999.0
12 HR PERSISTENCE (KT) : 0.0 -22.0 to 44.0 0.33 999.0
MULTI-LAYER SHEAR (KT) : 27.3 30.9 to 7.7 0.16 999.0
BL DRY-AIR FLUX (W/M2) : 24.4 816.2 to -81.4 0.88 999.0
D200 (10**7s-1) : 83.8 -33.0 to 159.5 0.61 999.0
MAXIMUM WIND (KT) : 20.0 22.5 to 132.0 0.00 0.0
STD DEV OF IR BR TEMP : 20.1 37.8 to 2.1 0.50 999.0
HEAT CONTENT (KJ/CM2) : 11.6 2.7 to 103.4 0.09 999.0
%area of TPW <45 mm upshear : 0.0 49.8 to 0.0 1.00 999.0
2nd PC OF IR BR TEMP : 0.8 2.2 to -2.3 0.32 999.0

SHIPS Prob RI for 20kt/ 12hr RI threshold= 0% is 0.0 times climatological mean ( 6.3%)
SHIPS Prob RI for 25kt/ 24hr RI threshold= 0% is 0.0 times climatological mean (12.5%)
SHIPS Prob RI for 30kt/ 24hr RI threshold= 0% is 0.0 times climatological mean ( 8.6%)
SHIPS Prob RI for 35kt/ 24hr RI threshold= 0% is 0.0 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= 0% is 0.0 times climatological mean ( 6.7%)
SHIPS Prob RI for 55kt/ 48hr RI threshold= 0% is 0.0 times climatological mean ( 5.9%)
SHIPS Prob RI for 65kt/ 72hr RI threshold= 0% is 0.0 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: 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0%
Logistic: 0.2% 2.4% 0.5% 0.2% 0.0% 0.7% 0.7% 0.7%
Bayesian: 0.0% 0.1% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0%
Consensus: 0.1% 0.8% 0.2% 0.1% 0.0% 0.2% 0.2% 0.2%
DTOPS: 999.0% 999.0% 999.0% 999.0% 999.0% 999.0% 999.0% 999.0%

## ANNULAR HURRICANE INDEX (AHI) EP932023 INVEST 07/07/23 12 UTC ##
## STORM NOT ANNULAR, SCREENING STEP FAILED, NPASS=6 NFAIL=1 ##
## AHI= 0 (AHI OF 100 IS BEST FIT TO ANN. STRUC., 1 IS MARGINAL, 0 IS NOT ANNULAR) ##

[Sciencerocks]

[Yellow Evan]

93E has not made the leap in organization I was expecting to overnight. While the eastern vorticity has become more amplified, the storm's overall strucutre has remained elongated with little organized central convection.



GFS has gradually trended towards a faster motion that moves 93E over cooler SSTs. This will seriously cut back on the time it has to intensify. I'd bet against this becoming a hurricane at this point.

[cycloneye]

Offshore of Southwestern Mexico (EP93):
Showers and thunderstorms associated with a broad area of low
pressure located several hundred miles south-southwest of
Manzanillo, Mexico, are gradually becoming better organized.
However, satellite imagery suggests that the circulation of the
low is elongated and lacks a well-defined center at this time.
Environmental conditions are expected to remain conducive for
additional development, and a tropical depression is likely to
form within the next day or so while the disturbance moves
generally west-northwestward, away from the coast of mainland
Mexico. Additional information on this system, including gale
warnings, can be found in High Seas Forecasts issued by the National
Weather Service.
* Formation chance through 48 hours...high...90 percent.
* Formation chance through 7 days...high...90 percent.

[Yellow Evan]

Convection is starting to increase by 105W that could lower pressures there and pave the door for TCG within 24 hours.