ATL: BRET - Remnants - Discussion

[tiger_deF]

This may be an unpopular opinion, but I think that the appearance of 92L has improved over the past 2 hours. If you look closely, while the convection is ragged, it appears to be coalescing around a center. Unlike 93L, the beginnings of a swirl is under the central convection. Furthermore, there is some banding evident on the last frame. There is limited outflow despite some dry air.

[tolakram]

Convection is increasing and possible some banding showing up.

http://i.imgur.com/EKlBy3Q.gif

[cycloneye]

Looks good in that animation.

[cycloneye]

 https://twitter.com/EricBlake12/status/876448368683339777

[TheStormExpert]

12z GFS initializes has this as a 1006mb weak TS which isn't the case. I have my doubts that Invest 92L ever gets a name at this point.

[TheStormExpert]

 https://twitter.com/EricBlake12/status/876448368683339777

And if it doesn't form(although it was so close), does it still mean a busy season? Looking at the satellite loop it looks to be a total mess heading into the unfavorable environment already.

[1900hurricane]

Despite the somewhat lackluster satellite appearance, 92L does appear to have improved at the surface.

 https://twitter.com/EricBlake12/status/876469830081290241

[Emmett_Brown]

I think the visible sat loop looks like it is holding its own. The GFS shows it holding together into the E Caribbean now. I still think this has a shot to develop tomorrow.

[Yellow Evan]

36~ hours left

* ATLANTIC SHIPS INTENSITY FORECAST *
* IR SAT DATA AVAILABLE, OHC AVAILABLE *
* INVEST AL922017 06/18/17 12 UTC *

TIME (HR) 0 6 12 18 24 36 48 60 72 84 96 108 120
V (KT) NO LAND 30 32 34 37 41 47 46 47 43 39 39 38 41
V (KT) LAND 30 32 34 37 41 47 46 47 43 33 35 35 37
V (KT) LGEM 30 32 35 37 39 41 40 37 33 27 28 27 28
Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP

SHEAR (KT) 2 2 5 8 7 15 19 25 27 28 12 11 17
SHEAR ADJ (KT) 5 6 6 4 2 6 7 7 1 0 5 1 0
SHEAR DIR 192 261 232 237 241 207 210 197 211 225 288 334 6
SST (C) 28.2 28.3 28.2 27.9 28.1 28.4 28.3 28.5 28.3 28.1 28.3 28.0 28.6
POT. INT. (KT) 143 145 143 139 141 145 145 147 144 140 142 137 145
ADJ. POT. INT. 159 160 157 151 153 155 153 152 144 135 133 125 132
200 MB T (C) -54.1 -53.8 -53.9 -54.3 -54.4 -53.7 -54.2 -53.5 -54.0 -53.4 -53.2 -52.8 -53.2
200 MB VXT (C) 0.0 0.0 0.0 0.0 0.0 -0.1 -0.1 -0.2 -0.2 -0.1 -0.1 0.1 0.1
TH_E DEV (C) 7 8 8 8 9 9 10 9 9 10 10 11 11
700-500 MB RH 65 64 64 63 62 61 58 60 61 57 56 54 54
MODEL VTX (KT) 12 12 12 13 14 16 13 13 10 7 5 2 2
850 MB ENV VOR 38 50 43 26 12 13 -6 14 -2 -20 -60 -96 -116
200 MB DIV 51 63 80 91 81 103 60 27 0 -9 -3 -27 -1
700-850 TADV -4 -7 -6 -5 -5 4 11 10 5 -1 0 -1 -5
LAND (KM) 533 433 352 331 371 274 287 279 73 -44 93 103 79
LAT (DEG N) 7.0 7.5 8.0 8.6 9.2 11.1 13.3 15.6 17.5 19.4 20.9 22.0 22.7
LONG(DEG W) 47.4 49.4 51.4 53.3 55.2 58.5 61.8 65.1 68.4 71.3 73.8 75.8 77.7
STM SPEED (KT) 20 20 20 20 19 19 20 19 18 15 12 10 10
HEAT CONTENT 39 39 45 29 35 39 47 32 55 60 18 18 34

FORECAST TRACK FROM TABM INITIAL HEADING/SPEED (DEG/KT):280/ 20 CX,CY: -19/ 3
T-12 MAX WIND: 25 PRESSURE OF STEERING LEVEL (MB): 605 (MEAN=618)
GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 14.1 (MEAN=14.5)
% GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 58.0 (MEAN=65.0)
PRELIM RI PROB (DV .GE. 55 KT IN 48 HR): 6.8

INDIVIDUAL CONTRIBUTIONS TO INTENSITY CHANGE
6 12 18 24 36 48 60 72 84 96 108 120
----------------------------------------------------------
SAMPLE MEAN CHANGE 1. 2. 3. 4. 6. 8. 9. 10. 11. 12. 13. 13.
SST POTENTIAL 0. 0. 1. 2. 6. 12. 18. 22. 26. 29. 31. 33.
VERTICAL SHEAR MAG 1. 2. 3. 5. 6. 5. 4. 2. -1. -2. -2. -3.
VERTICAL SHEAR ADJ -0. -1. -1. -1. -2. -3. -5. -5. -4. -4. -4. -3.
VERTICAL SHEAR DIR -0. -1. -2. -3. -5. -7. -8. -10. -11. -11. -12. -11.
PERSISTENCE 1. 1. 2. 2. 2. 2. 1. 1. 1. 0. 0. -0.
200/250 MB TEMP. -0. -0. -1. -1. -1. -1. -1. -1. -0. -0. 0. 1.
THETA_E EXCESS -0. -0. -0. -0. 0. 0. 0. 0. 0. 0. 0. 1.
700-500 MB RH -0. -0. -0. -1. -1. -1. -2. -2. -3. -3. -3. -2.
MODEL VTX TENDENCY -0. -0. 0. 1. 3. -0. -2. -7. -11. -14. -19. -19.
850 MB ENV VORTICITY 0. 0. 0. 0. 0. -0. -0. -0. -1. -1. -2. -3.
200 MB DIVERGENCE 0. 0. 1. 1. 1. 1. 1. 1. 1. 0. 0. -0.
850-700 T ADVEC 0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0.
ZONAL STORM MOTION -0. 0. 1. 1. 2. 3. 3. 3. 4. 5. 6. 6.
STEERING LEVEL PRES 0. 0. 0. 0. 0. 0. 0. 0. -0. -0. -0. -0.
DAYS FROM CLIM. PEAK 0. 0. 0. 0. 0. 0. 1. 1. 1. 2. 2. 2.
GOES PREDICTORS 0. 0. 0. 0. -0. -1. -2. -2. -2. -2. -2. -2.
OCEAN HEAT CONTENT -0. -0. -0. -0. -0. -1. -1. -1. -1. -1. -1. -0.
----------------------------------------------------------
TOTAL CHANGE 2. 4. 7. 11. 17. 16. 17. 13. 9. 9. 8. 11.

CURRENT MAX WIND (KT): 30. LAT, LON: 7.0 47.4

** 2017 ATLANTIC RI INDEX AL922017 INVEST 06/18/17 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
12 HR PERSISTENCE (KT): 5.0 -49.5 to 33.0 0.66 7.5
850-200 MB SHEAR (KT) : 4.8 30.1 to 2.9 0.93 4.2
HEAT CONTENT (KJ/cm2) : 37.4 0.0 to 156.2 0.24 1.0
2nd PC OF IR BR TEMP : 0.1 2.4 to -3.0 0.42 2.0
STD DEV OF IR BR TEMP : 14.1 36.6 to 2.8 0.67 3.2
MAXIMUM WIND (kt) : 30.0 22.5 to 121.0 0.21 0.5
POT = MPI-VMAX (KT) : 126.0 28.4 to 139.6 0.88 2.8
D200 (10**7s-1) : 73.2 -29.7 to 181.5 0.49 0.7
BL DRY-AIR FLUX (w/m2): 126.6 961.4 to -67.1 0.81 0.0
% AREA WITH TPW <45 mm: 0.0 100.0 to 0.0 1.00 0.2

SHIPS Prob RI for 20kt/ 12hr RI threshold= 8% is 1.5 times sample mean ( 5.4%)
SHIPS Prob RI for 25kt/ 24hr RI threshold= 41% is 3.5 times sample mean (11.5%)
SHIPS Prob RI for 30kt/ 24hr RI threshold= 22% is 3.0 times sample mean ( 7.4%)
SHIPS Prob RI for 35kt/ 24hr RI threshold= 10% is 2.2 times sample mean ( 4.3%)
SHIPS Prob RI for 40kt/ 24hr RI threshold= 8% is 2.9 times sample mean ( 2.8%)
SHIPS Prob RI for 45kt/ 36hr RI threshold= 15% is 2.9 times sample mean ( 5.1%)
SHIPS Prob RI for 55kt/ 48hr RI threshold= 18% is 3.4 times sample mean ( 5.3%)
SHIPS Prob RI for 65kt/ 72hr RI threshold= 19% is 3.2 times sample mean ( 6.0%)

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: 8.0% 40.7% 22.0% 9.7% 8.2% 14.8% 17.9% 18.9%
Logistic: 6.6% 39.2% 21.2% 9.6% 9.0% 11.7% 16.4% 17.7%
Bayesian: 0.8% 3.7% 0.6% 0.1% 0.0% 0.4% 0.7% 1.3%
Consensus: 5.1% 27.9% 14.6% 6.4% 5.8% 8.9% 11.7% 12.7%

## ANNULAR HURRICANE INDEX (AHI) AL922017 INVEST 06/18/17 12 UTC ##
## STORM NOT ANNULAR, SCREENING STEP FAILED, NPASS=4 NFAIL=3 ##
## AHI= 0 (AHI OF 100 IS BEST FIT TO ANN. STRUC., 1 IS MARGINAL, 0 IS NOT ANNULAR) ##

** PROBLTY OF AT LEAST 1 SCNDRY EYEWL FORMTN EVENT AL922017 INVEST 06/18/2017 12 UTC **
TIME(HR) 0-12 12-24(0-24) 24-36(0-36) 36-48(0-48)
CLIMO(%) 0 0( 0) 0( 0) 0( 0) <-- PROB BASED ON INTENSITY ONLY
PROB(%) 0 0( 0) 0( 0) 0( 0) <-- FULL MODEL PROB (RAN NORMALLY)

** DSHIPS INTENSITY FORECAST ADJUSTED RELATIVE TO ONSET OF ERC WEAKENING PHASE **
TIME (HR) 0 6 12 18 24 36 48 60 72 84 96 108 120
>24HR AGO (DSHIPS) 30 32 34 37 41 47 46 47 43 33 35 35 37
18HR AGO 30 29 31 34 38 44 43 44 40 30 32 32 34
12HR AGO 30 27 26 29 33 39 38 39 35 25 27 27 29
6HR AGO 30 24 21 20 24 30 29 30 26 16 18 18 20
NOW CURRENT INTENSITY < 83 KT
IN 6HR INTENSITY IN 6HR < 83 KT
IN 12HR INTENSITY IN 12HR < 83 KT

[Yellow Evan]

No evidence of curved banding features, but I still think this will develop before conditions become hostile on Tuesday.

[cycloneye]

First mission on Monday afternoon.

Code: Select all

SUSPECT AREA (EAST OF TRINIDAD)
       FLIGHT ONE -- TEAL 74          FLIGHT TWO -- TEAL 75
       A. 19/1800Z                    A. 20/0530Z,1130Z
       B. AFXXX 01AAA INVEST          B. AFXXX 0202A CYCLONE
       C. 19/1500Z                    C. 20/0300Z
       D. 9.0N 56.0W                  D. 10.5N 60.0W
       E. 19/1730Z TO 19/2130Z        E. 20/0500Z TO 20/1130Z
       F. SFC TO 10,000 FT            F. SFC TO 10,000 FT

[Aric Dunn]

Ragged convective patter for sure. but the surface structure has definitely become more apparent with the classic V shape int he ITCZ around it. The last few hours some deeper convection has developed very near the what would likely become the closed circ. convection is key right now and well slowing down a little would help.

[cycloneye]

2 PM TWO:60%-60%

Showers and thunderstorms associated with a tropical wave about 800
miles east-southeast of the southern Windward Islands have become a
little better organized since yesterday. Some additional
development of this system is possible during the next couple of
days before environmental conditions become less favorable for
tropical cyclone formation. This system is forecast to move to the
west-northwest at near 20 mph toward the Windward Islands and
northeastern South America during the next two days, and interests
in these areas should monitor its progress. Regardless of
development, locally heavy rains and gusty winds are likely to
spread over portions of the Windward Islands Monday night and
Tuesday. An Air Force Reserve Hurricane Hunter aircraft is
scheduled to investigate this system on Monday, if necessary.
* Formation chance through 48 hours...medium...60 percent.
* Formation chance through 5 days...medium...60 percent.

[NDG]

Another look at the ASCAT from earlier today.

[gatorcane]

12Z EC down to 1006mb in 24 hours. Considering the EC had nothing from this just a couple of days ago, I would say this was a forecast bust for this model.

[NDG]

12Z EC down to 1006mb in 24 hours. Considering the EC had nothing from this just a couple of days ago, I would say this was a forecast bust for this model.

I agree, the NHC will probably go up again on development chances now that the Euro is on board.

[Hammy]

The argument could be made for this being closed--the models have always shown a fairly small system.

[weathaguyry]

I truly believe this will become Bret. By the look of it, the structure was disrupted a little when it left the ITCZ, but 92L hasn't had too much trouble producing it's own convection. I truly believe Recon will find a closed low tomorrow, and that this will get upgraded to TD 2/TS Bret tomorrow at 5PM. This is just my opinion though

[tolakram]

Saved RGB loop. Starting to look like something/

[Dougiefresh]

Latest ASCATT getting tighter.