ATL: FOUR - Remnants - Discussion

[Hurricaneman]

It's heading w to wnw after that erroneous north movement between 24 and 48 hours

[Kingarabian]

0Z MU MUCH weaker through 48 hrs. Actually shows weakening during this time period

of course, it's likely BS as it somehow shifted north and has the center in line with Dominica in 54 hours... all the way to 15N

They have to be on to something since the GFS, UKMET, and Euro are all lining up now.

Unless the environment data is mixed up.

The NHC should ask for G-IV plane to go check it out or send a drone from NOAA.

[Alyono]

0Z MU MUCH weaker through 48 hrs. Actually shows weakening during this time period

of course, it's likely BS as it somehow shifted north and has the center in line with Dominica in 54 hours... all the way to 15N

They have to be on to something since the GFS, UKMET, and Euro are all lining up now.

Unless the environment data is mixed up.

The NHC should ask for G-IV plane to go check it out or send a drone from NOAA.

not getting synoptic surveillance this far out

Of course, we saw with Matthew the models can absolutely butcher the steering flow, when they had a ridge vanish for no reason

As good as modeling is today, there remains some error, some due to paramaterization, some due to bad data, and a LOT due to rounding errors (we're solving millions of PDEs that have no explicit solutions numerically. That will ALWAYS create error)

[Alyono]

one thing that is becoming clear, the subtropical western Atlantic will be UNFAVORABLE for this. Doesn't look favorable like it did 24 hours ago

[Alyono]

UKMET also drops it


NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 12 HOURS
FORECAST POSITION AT T+ 12 : 10.1N 33.8W

LEAD CENTRAL MAXIMUM WIND
VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)
-------------- ---- -------- ------------- -------------
1200UTC 04.07.2017 12 10.1N 33.8W 1013 22
0000UTC 05.07.2017 24 11.5N 34.6W 1013 24
1200UTC 05.07.2017 36 12.3N 36.4W 1014 24
0000UTC 06.07.2017 48 13.0N 38.6W 1014 25
1200UTC 06.07.2017 60 CEASED TRACKING

I sure would not be increasing development chances after the 0Z models have all trended dramatically weaker, even though it seems suspect

[Kingarabian]

Well 94L is going to have to detoriate rather quickly if those models are going to verify.

[Hurricaneman]

Well 94L is going to have to detoriate rather quickly if those models are going to verify.

I must say the models seem to be a complete fail on this cycle and we should wait until the next cycle and of course wait until the Euro comes out in a few hours

[TheStormExpert]

one thing that is becoming clear, the subtropical western Atlantic will be UNFAVORABLE for this. Doesn't look favorable like it did 24 hours ago

Just an hour ago you were disagreeing with these models, these forecasts too are beyond 5-7 days and we know how bad shear forecast tend to be.

[Hurricaneman]

The GFS seems to be at 27.5n 71.5w at 210 hrs with low wind shear but based on that one would think this would be stronger in that sort of environment but it could also be wrong so who knows

[Ntxw]

Well 94L is going to have to detoriate rather quickly if those models are going to verify.

I must say the models seem to be a complete fail on this cycle and we should wait until the next cycle and of course wait until the Euro comes out in a few hours

I don't think it's a good idea to disregard a set of runs because they show something different. It doesn't mean they are right either, you have to take long term forecasts (beyond 3-5 days) as simply educated guesses. It's even more questionable be it a strong or weak run when you're looking at a broad, monsoonal feature such as this. There is more to conditions than just shear such as dry air at various levels of the atmosphere, interactions with TUTT features, sinking and rising air etc.

[Bocadude85]

The 0z HWRF is coming in stronger then the 18Z so far.

The 0Z Canadian is also stronger in its long range forecast with a North Carolina landfall.

[Digital-TC-Chaser]

Well 94L is going to have to detoriate rather quickly if those models are going to verify.

I must say the models seem to be a complete fail on this cycle and we should wait until the next cycle and of course wait until the Euro comes out in a few hours

I don't think it's a good idea to disregard a set of runs because they show something different. It doesn't mean they are right either, you have to take long term forecasts (beyond 3-5 days) as simply educated guesses. It's even more questionable be it a strong or weak run when you're looking at a broad, monsoonal feature such as this. There is more to conditions than just shear such as dry air at various levels of the atmosphere, interactions with TUTT features, sinking and rising air etc.

Tutts can either hinder intensification with shear or aid the tropical cyclone genesis.

[tolakram]

The loop to watch overnight.

http://rammb.cira.colostate.edu/ramsdis/online/loop.asp?data_folder=tropical/tropical_ge_4km_visir2_floater_2&width=640&height=480&number_of_images_to_display=12

[NotoSans]

Up to 70/80 as per latest TWO

[AxaltaRacing24]

Code RED for the next 48 hrs.

[Digital-TC-Chaser]

Already Look a Depression -atm.
https://www.nrlmry.navy.mil/tropics-bin ... PE=Instant

[Hammy]

Euro stronger than earlier run (and latest GFS) and maintains a closed low through at least 72 hours.

[Yellow Evan]

* ATLANTIC SHIPS INTENSITY FORECAST *
* IR SAT DATA AVAILABLE, OHC AVAILABLE *
* INVEST AL942017 07/04/17 06 UTC *

TIME (HR) 0 6 12 18 24 36 48 60 72 84 96 108 120
V (KT) NO LAND 30 33 36 39 42 48 56 63 71 75 77 76 75
V (KT) LAND 30 33 36 39 42 48 56 63 71 75 77 76 75
V (KT) LGEM 30 32 34 35 36 39 44 51 60 68 76 80 80
Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP

SHEAR (KT) 20 23 20 17 16 11 5 7 6 6 2 3 11
SHEAR ADJ (KT) -4 -5 -3 -3 -6 -3 2 -1 0 -1 7 13 6
SHEAR DIR 43 43 47 53 46 48 32 32 30 64 242 211 234
SST (C) 27.7 27.6 27.5 27.4 27.2 26.5 26.5 26.8 27.2 27.7 27.7 27.9 28.3
POT. INT. (KT) 130 129 129 129 127 121 121 125 129 135 135 138 143
ADJ. POT. INT. 124 124 126 128 127 122 123 126 131 137 134 137 142
200 MB T (C) -54.6 -54.6 -54.3 -54.5 -54.8 -54.1 -54.7 -54.1 -54.3 -54.2 -54.4 -54.3 -54.6
200 MB VXT (C) 0.0 -0.1 -0.2 -0.2 -0.2 -0.2 0.0 0.0 0.0 0.1 0.1 0.1 0.3
TH_E DEV (C) 5 5 5 5 5 5 6 7 7 9 9 10 11
700-500 MB RH 73 75 78 79 79 73 68 64 62 55 51 50 49
MODEL VTX (KT) 11 13 13 13 13 13 14 14 14 13 13 11 9
850 MB ENV VOR 36 33 23 13 4 -3 -8 -2 13 12 7 -3 -3
200 MB DIV 64 64 70 79 81 39 17 23 43 28 7 -2 12
700-850 TADV -1 -3 -3 -4 -7 -8 3 0 4 2 1 4 5
LAND (KM) 1892 1904 1917 1883 1821 1613 1415 1225 1074 1008 823 686 317
LAT (DEG N) 9.1 xx.x xx.x xx.x xx.x xx.x xx.x xx.x xx.x xx.x xx.x xx.x xx.x
LONG(DEG W) 33.9 xxx.x xxx.x xxx.x xxx.x xxx.x xxx.x xxx.x xxx.x xxx.x xxx.x xxx.x xxx.x
STM SPEED (KT) 4 4 7 10 12 15 17 18 17 17 16 17 17
HEAT CONTENT 18 19 19 22 27 9 6 16 12 22 32 21 37

FORECAST TRACK FROM OFPI INITIAL HEADING/SPEED (DEG/KT):275/ 4 CX,CY: -3/ 0
T-12 MAX WIND: 25 PRESSURE OF STEERING LEVEL (MB): 644 (MEAN=618)
GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 21.7 (MEAN=14.5)
% GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 68.0 (MEAN=65.0)
PRELIM RI PROB (DV .GE. 55 KT IN 48 HR): 3.1

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 1. 1. 2. 3. 6. 10. 14. 18. 21. 24. 26. 28.
VERTICAL SHEAR MAG -0. -1. -1. -1. -1. 0. 2. 3. 4. 6. 7. 7.
VERTICAL SHEAR ADJ 0. 1. 1. 2. 3. 4. 4. 4. 4. 3. 2. 1.
VERTICAL SHEAR DIR 0. 1. 2. 3. 5. 8. 10. 13. 15. 14. 13. 11.
PERSISTENCE 1. 1. 2. 2. 2. 2. 1. 1. 1. 0. 0. -0.
200/250 MB TEMP. -0. -0. -0. -0. -0. -0. -0. 0. 0. 1. 2. 2.
THETA_E EXCESS -0. -0. -1. -1. -1. -1. -1. -1. -2. -2. -1. -1.
700-500 MB RH -0. -0. -1. -1. -2. -4. -5. -5. -6. -5. -4. -4.
MODEL VTX TENDENCY 0. 1. 0. 0. 0. 1. 0. 1. -2. -3. -7. -9.
850 MB ENV VORTICITY 0. 0. -0. -0. -0. -1. -1. -1. -1. -1. -1. -2.
200 MB DIVERGENCE 0. 0. 1. 1. 1. 1. 1. 1. 1. 0. 0. -0.
850-700 T ADVEC 0. -0. -0. -0. -0. -1. -1. -1. -1. -1. -1. -0.
ZONAL STORM MOTION -0. 0. 0. 0. -0. -0. -0. -0. -1. -1. -1. -1.
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. 1. 1. 0. 0. -0. -0. -1. -1. -1. -1.
OCEAN HEAT CONTENT -0. -0. -0. -0. -0. -1. -1. -1. -1. -1. -1. -0.
----------------------------------------------------------
TOTAL CHANGE 3. 6. 9. 12. 18. 26. 33. 41. 45. 47. 46. 45.

CURRENT MAX WIND (KT): 30. LAT, LON: 9.1 33.9

** 2017 ATLANTIC RI INDEX AL942017 INVEST 07/04/17 06 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 4.3
850-200 MB SHEAR (KT) : 19.4 30.1 to 2.9 0.39 1.0
HEAT CONTENT (KJ/cm2) : 21.0 0.0 to 156.2 0.13 0.3
2nd PC OF IR BR TEMP : 0.5 2.4 to -3.0 0.35 0.9
STD DEV OF IR BR TEMP : 21.7 36.6 to 2.8 0.44 1.2
MAXIMUM WIND (kt) : 30.0 22.5 to 121.0 0.21 0.3
POT = MPI-VMAX (KT) : 95.8 28.4 to 139.6 0.61 1.1
D200 (10**7s-1) : 71.6 -29.7 to 181.5 0.48 0.4
BL DRY-AIR FLUX (w/m2): 36.2 961.4 to -67.1 0.90 0.0
% AREA WITH TPW <45 mm: 0.0 100.0 to 0.0 1.00 0.1

SHIPS Prob RI for 20kt/ 12hr RI threshold= 4% is 0.8 times sample mean ( 5.4%)
SHIPS Prob RI for 25kt/ 24hr RI threshold= 13% is 1.1 times sample mean (11.5%)
SHIPS Prob RI for 30kt/ 24hr RI threshold= 10% is 1.3 times sample mean ( 7.4%)
SHIPS Prob RI for 35kt/ 24hr RI threshold= 6% is 1.4 times sample mean ( 4.3%)
SHIPS Prob RI for 40kt/ 24hr RI threshold= 5% is 1.7 times sample mean ( 2.8%)
SHIPS Prob RI for 45kt/ 36hr RI threshold= 10% is 1.9 times sample mean ( 5.1%)
SHIPS Prob RI for 55kt/ 48hr RI threshold= 12% is 2.2 times sample mean ( 5.3%)
SHIPS Prob RI for 65kt/ 72hr RI threshold= 18% is 3.0 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: 4.1% 13.0% 9.7% 5.8% 4.7% 9.8% 11.5% 18.1%
Logistic: 2.9% 7.7% 3.0% 0.5% 0.0% 3.0% 8.1% 12.2%
Bayesian: 2.4% 19.9% 2.5% 0.1% 0.0% 0.8% 1.3% 1.2%
Consensus: 3.1% 13.5% 5.1% 2.1% 1.6% 4.6% 7.0% 10.5%

** PROBLTY OF AT LEAST 1 SCNDRY EYEWL FORMTN EVENT AL942017 INVEST 07/04/2017 06 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 33 36 39 42 48 56 63 71 75 77 76 75
18HR AGO 30 29 32 35 38 44 52 59 67 71 73 72 71
12HR AGO 30 27 26 29 32 38 46 53 61 65 67 66 65
6HR AGO 30 24 21 20 23 29 37 44 52 56 58 57 56
NOW CURRENT INTENSITY < 83 KT
IN 6HR INTENSITY IN 6HR < 83 KT
IN 12HR INTENSITY IN 12HR < 83 K

[bamajammer4eva]

Here is the Euro animated-it nearly loses it for a bit then picks it back up and is a 1009mb Low at the end by that model

[Digital-TC-Chaser]