ATL: NATE - Post Tropical - Discussion

[galaxy401]

Is the SMFR winds legit or is it contaminated due to land?

[ColdMiser123]

UMKET makes landfall at the Delta, then into MS/AL

Getting to the point where we NEED this to go east of New Orleans or else we could be looking at a horrible disaster given the trends this evening in terms of intensity

How strong?

Looks like 971 mb according to the text product.

[djones65]

The SFMR data may not be reliable due to shoaling effects since center is so close to north coast of Honduras. I would put greater emphasis on flt level wind data until Nate gets further north and shoaling wouldn't be much of an issue.
But 54 knot 850 mb winds would correspond to 45 knots at surface.

[Bamagirl2408]

UMKET makes landfall at the Delta, then into MS/AL

Getting to the point where we NEED this to go east of New Orleans or else we could be looking at a horrible disaster given the trends this evening in terms of intensity

How has ukmet performed? (Confidence factor)

[NDG]

Looks like half of the COC is now offshore, with some deep convection right on the western quadrant, part of the core.

[psyclone]

Nate is looking vigorous for having spent so much time over land. Very impressive convection is firing over the center and in long, curved bands well to the east. it looks like Grand Cayman is under one of those heavy bands. this may well overperform near term and perhaps later on. I'd be paying very close attention in those watch areas.

[NDG]

Is the SMFR winds legit or is it contaminated due to land?

Over shallow waters and heavy rain contaminated.

[bella_may]

UMKET makes landfall at the Delta, then into MS/AL

Getting to the point where we NEED this to go east of New Orleans or else we could be looking at a horrible disaster given the trends this evening in terms of intensity

How strong?

Looks like 971 mb according to the text product.

Isn't that a low cat 2?

[LarryWx]

MET OFFICE TROPICAL CYCLONE GUIDANCE FOR NORTH-EAST PACIFIC AND ATLANTIC

GLOBAL MODEL DATA TIME 0000UTC 06.10.2017

TROPICAL STORM NATE ANALYSED POSITION : 15.3N 83.5W

ATCF IDENTIFIER : AL162017

LEAD CENTRAL MAXIMUM WIND
VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)
-------------- ---- -------- ------------- -------------
0000UTC 06.10.2017 0 15.3N 83.5W 999 39
1200UTC 06.10.2017 12 18.5N 84.7W 993 40
0000UTC 07.10.2017 24 21.9N 86.5W 990 46
1200UTC 07.10.2017 36 25.6N 89.1W 983 56
0000UTC 08.10.2017 48 28.2N 90.0W 976 59
1200UTC 08.10.2017 60 30.8N 88.3W 971 52
0000UTC 09.10.2017 72 34.3N 85.0W 984 30
1200UTC 09.10.2017 84 37.7N 79.9W 996 24
0000UTC 10.10.2017 96 40.5N 73.8W 1001 39
1200UTC 10.10.2017 108 42.0N 69.1W 1004 35

UKMET much stronger

There's a big initialization problem with UK and that has a lot to do with how strong it is and how far east its track is. First of all, it already had it just going offshore at 0Z (8 PM), or 4 hours early over hot water, and a whopping full degree east of where it actually was at 8 PM. UK had it at 83.5W and it was at 84.5 W per NHC! Shear is likely less there, too. Then, partially because of that too far east initialization, UK send him E of the Yucatan! So, that is another reason why it has him so strong. Can anyone think of a reason that this run shouldn't be thrown in the trash?

[CrazyC83]

URNT15 KNHC 060430
AF305 0316A NATE HDOB 34 20171006
042030 1615N 08538W 8432 01522 0051 +163 +147 031026 028 020 001 00
042100 1616N 08540W 8430 01526 0051 +164 +145 029028 029 022 001 00
042130 1616N 08541W 8433 01523 0051 +165 +145 029026 028 021 001 00
042200 1617N 08543W 8433 01524 0052 +164 +145 029026 027 022 001 03
042230 1618N 08545W 8425 01531 0050 +165 +144 028027 028 024 001 00
042300 1619N 08546W 8429 01529 0050 +166 +144 026028 028 024 002 00
042330 1620N 08547W 8430 01526 0052 +166 +142 029028 029 025 002 00
042400 1620N 08549W 8440 01516 0060 +152 +147 032029 029 027 008 00
042430 1621N 08550W 8457 01500 0057 +160 +151 028027 028 027 008 00
042500 1622N 08552W 8490 01470 0053 +167 +150 025027 028 025 001 00
042530 1623N 08553W 8445 01510 0054 +162 +154 031028 029 025 008 03
042600 1623N 08555W 8430 01529 0052 +169 +134 025028 029 020 002 00
042630 1624N 08556W 8426 01534 0053 +166 +145 025026 028 027 002 00
042700 1624N 08558W 8431 01528 0064 +148 +148 032027 028 028 003 00
042730 1625N 08600W 8433 01525 0069 +152 +152 026029 030 030 017 00
042800 1625N 08601W 8429 01531 0063 +157 +156 022023 027 029 004 00
042830 1625N 08603W 8435 01525 0058 +160 +155 023021 024 026 003 01
042900 1626N 08605W 8420 01542 0059 +160 +154 026021 024 025 003 01
042930 1626N 08607W 8436 01525 0059 +161 +139 028023 024 022 001 00
043000 1627N 08608W 8428 01533 0059 +165 +133 031025 025 023 010 03
$$
;

[CrazyC83]

URNT15 KNHC 060440
AF305 0316A NATE HDOB 35 20171006
043030 1627N 08610W 8429 01533 0061 +165 +135 030025 025 028 000 00
043100 1628N 08612W 8433 01532 0062 +165 +131 028024 025 022 001 00
043130 1628N 08613W 8426 01539 0062 +165 +130 030026 026 019 001 00
043200 1629N 08615W 8436 01531 0065 +164 +135 035026 026 018 001 03
043230 1630N 08615W 8426 01542 0068 +160 +141 037023 025 /// /// 03
043300 1630N 08614W 8430 01536 0064 +164 +134 030022 022 018 001 00
043330 1629N 08613W 8432 01532 0062 +165 +134 024021 022 019 000 00
043400 1628N 08611W 8429 01535 0061 +164 +134 023021 021 020 000 03
043430 1627N 08610W 8429 01533 0060 +165 +130 024020 021 044 002 03
043500 1627N 08608W 8430 01475 0015 +164 +134 026017 019 136 027 03
043530 1626N 08607W 8429 01531 0057 +160 +139 026017 018 059 006 00
043600 1626N 08605W 8430 01531 0060 +155 +151 018016 019 026 004 01
043630 1625N 08604W 8427 01533 0062 +157 +154 022020 022 025 005 00
043700 1625N 08602W 8428 01531 0064 +151 +148 025021 022 022 007 00
043730 1624N 08600W 8430 01528 0061 +152 +142 029022 022 023 005 00
043800 1624N 08559W 8426 01532 0060 +152 +151 037023 024 024 004 01
043830 1623N 08557W 8428 01530 0056 +160 +152 037022 024 020 003 00
043900 1623N 08556W 8430 01528 0054 +159 +154 033023 024 019 002 00
043930 1622N 08554W 8432 01526 0052 +165 +151 035022 024 019 001 00
044000 1622N 08553W 8428 01530 0052 +165 +145 030023 024 022 001 00
$$
;


The SFMR is on crack this set. Discard it.

[CrazyC83]

Is the SMFR winds legit or is it contaminated due to land?

Over shallow waters and heavy rain contaminated.

I'd still go 45 kt based on the flight level winds (the SFMR appears to be completely off the mark this flight with that bogus 136 kt reading), although they were far removed from the circulation center.

[CrazyC83]

URNT15 KNHC 060450
AF305 0316A NATE HDOB 36 20171006
044030 1622N 08553W 8428 01530 0052 +165 +139 028024 025 023 001 00
044100 1621N 08549W 8430 01527 0053 +162 +146 027024 025 024 001 00
044130 1620N 08548W 8429 01529 0054 +160 +147 026023 024 021 001 00
044200 1620N 08546W 8430 01526 0054 +160 +143 026022 022 019 001 00
044230 1619N 08545W 8430 01525 0053 +160 +138 024022 022 020 000 00
044300 1619N 08543W 8429 01526 0052 +160 +135 026024 024 021 000 00
044330 1618N 08541W 8432 01522 0051 +162 +132 025025 026 020 000 00
044400 1618N 08540W 8429 01524 0049 +162 +134 022026 027 020 001 00
044430 1617N 08538W 8429 01521 0049 +160 +142 023026 027 021 000 00
044500 1617N 08537W 8428 01523 0047 +163 +138 017028 029 023 001 00
044530 1616N 08535W 8421 01531 0046 +162 +145 017027 030 023 003 00
044600 1616N 08533W 8434 01516 0046 +159 +146 017029 030 027 006 00
044630 1615N 08532W 8428 01521 0049 +152 +151 023028 029 027 006 00
044700 1615N 08530W 8430 01518 0053 +150 +150 023027 028 028 012 00
044730 1614N 08529W 8429 01517 0047 +152 +148 019026 027 031 012 00
044800 1614N 08527W 8429 01517 0044 +155 +146 016023 025 028 009 00
044830 1613N 08525W 8429 01516 0040 +160 +144 014020 021 029 009 00
044900 1613N 08524W 8430 01514 0040 +159 +147 012022 023 029 009 00
044930 1612N 08522W 8429 01515 0040 +156 +151 014023 024 030 007 00
045000 1612N 08521W 8429 01514 0038 +159 +149 015023 024 029 008 00
$$
;

[Alyono]

MET OFFICE TROPICAL CYCLONE GUIDANCE FOR NORTH-EAST PACIFIC AND ATLANTIC

GLOBAL MODEL DATA TIME 0000UTC 06.10.2017

TROPICAL STORM NATE ANALYSED POSITION : 15.3N 83.5W

ATCF IDENTIFIER : AL162017

LEAD CENTRAL MAXIMUM WIND
VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)
-------------- ---- -------- ------------- -------------
0000UTC 06.10.2017 0 15.3N 83.5W 999 39
1200UTC 06.10.2017 12 18.5N 84.7W 993 40
0000UTC 07.10.2017 24 21.9N 86.5W 990 46
1200UTC 07.10.2017 36 25.6N 89.1W 983 56
0000UTC 08.10.2017 48 28.2N 90.0W 976 59
1200UTC 08.10.2017 60 30.8N 88.3W 971 52
0000UTC 09.10.2017 72 34.3N 85.0W 984 30
1200UTC 09.10.2017 84 37.7N 79.9W 996 24
0000UTC 10.10.2017 96 40.5N 73.8W 1001 39
1200UTC 10.10.2017 108 42.0N 69.1W 1004 35

UKMET much stronger

There's a big initialization problem with UK and that has a lot to do with how strong it is and how far east its track is. First of all, it already had it just going offshore at 0Z (8 PM), or 4 hours early over hot water, and a whopping full degree east of where it actually was at 8 PM. UK had it at 83.5W and it was at 84.5 W per NHC! Shear is likely less there, too. Then, partially because of that too far east initialization, UK send him E of the Yucatan! So, that is another reason why it has him so strong. Can anyone think of a reason that this run shouldn't be thrown in the trash?

The thing is, some ensemble guidance I have seen also shows a track east of the Yucatan. The initial intensity is accurate based upon the aircraft data

[LarryWx]

0Z GEFS mean 100 miles E of last 3 runs far e LA.

[CrazyC83]

URNT15 KNHC 060500
AF305 0316A NATE HDOB 37 20171006
045030 1611N 08519W 8429 01514 0038 +159 +147 013023 023 030 008 00
045100 1611N 08517W 8431 01511 0036 +162 +145 011023 024 030 005 00
045130 1610N 08516W 8432 01510 0034 +162 +151 005024 026 029 005 00
045200 1610N 08514W 8430 01509 0036 +158 +150 003022 023 030 005 00
045230 1609N 08512W 8431 01509 0037 +152 +151 011021 022 030 005 00
045300 1609N 08511W 8430 01509 0032 +159 +152 004019 020 033 009 00
045330 1608N 08509W 8425 01510 0036 +160 +160 359020 023 036 011 00
045400 1608N 08507W 8430 01505 0039 +155 +155 012018 019 036 020 00
045430 1607N 08506W 8439 01491 0042 +149 +149 354015 020 049 051 03
045500 1607N 08504W 8417 01516 0038 +159 +159 012022 024 050 049 00
045530 1606N 08502W 8423 01510 0036 +166 +166 020020 022 045 028 00
045600 1606N 08501W 8432 01503 0036 +168 +168 022022 024 045 022 00
045630 1605N 08459W 8431 01500 0029 +168 +168 031026 027 045 020 00
045700 1605N 08458W 8424 01502 0027 +170 +170 029022 024 046 015 03
045730 1604N 08456W 8428 01501 0025 +167 //// 021017 023 040 009 01
045800 1604N 08454W 8433 01494 //// +165 //// 016014 015 033 005 01
045830 1603N 08453W 8422 01504 //// +168 //// 013014 015 028 002 01
045900 1603N 08451W 8428 01497 0010 +169 +166 001015 015 023 001 05
045930 1602N 08450W 8428 01495 0009 +167 +164 008017 018 018 001 01
050000 1602N 08448W 8432 01490 0008 +165 +164 011014 018 018 001 01
$$
;


27 kt FL, 50 kt SFMR.

[Chris90]

Is the SMFR winds legit or is it contaminated due to land?

Over shallow waters and heavy rain contaminated.

I'd still go 45 kt based on the flight level winds (the SFMR appears to be completely off the mark this flight with that bogus 136 kt reading), although they were far removed from the circulation center.

Could the shoaling inflate the sfmr readings that much to 136kts, or is there a chance that the instrument is having technical difficulties?
Obviously that reading is way off the mark, and now I'm wondering if the 50kt reading was way off the mark too, considering it didn't seem like anyone expected it to emerge off the coast with even TS force winds.

[Alyono]

Over shallow waters and heavy rain contaminated.

I'd still go 45 kt based on the flight level winds (the SFMR appears to be completely off the mark this flight with that bogus 136 kt reading), although they were far removed from the circulation center.

Could the shoaling inflate the sfmr readings that much to 136kts, or is there a chance that the instrument is having technical difficulties?
Obviously that reading is way off the mark, and now I'm wondering if the 50kt reading was way off the mark too, considering it didn't seem like anyone expected it to emerge off the coast with even TS force winds.

the 136 kts is likely over an island

[LarryWx]

MET OFFICE TROPICAL CYCLONE GUIDANCE FOR NORTH-EAST PACIFIC AND ATLANTIC

GLOBAL MODEL DATA TIME 0000UTC 06.10.2017

TROPICAL STORM NATE ANALYSED POSITION : 15.3N 83.5W

ATCF IDENTIFIER : AL162017

LEAD CENTRAL MAXIMUM WIND
VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)
-------------- ---- -------- ------------- -------------
0000UTC 06.10.2017 0 15.3N 83.5W 999 39
1200UTC 06.10.2017 12 18.5N 84.7W 993 40
0000UTC 07.10.2017 24 21.9N 86.5W 990 46
1200UTC 07.10.2017 36 25.6N 89.1W 983 56
0000UTC 08.10.2017 48 28.2N 90.0W 976 59
1200UTC 08.10.2017 60 30.8N 88.3W 971 52
0000UTC 09.10.2017 72 34.3N 85.0W 984 30
1200UTC 09.10.2017 84 37.7N 79.9W 996 24
0000UTC 10.10.2017 96 40.5N 73.8W 1001 39
1200UTC 10.10.2017 108 42.0N 69.1W 1004 35

UKMET much stronger

There's a big initialization problem with UK and that has a lot to do with how strong it is and how far east its track is. First of all, it already had it just going offshore at 0Z (8 PM), or 4 hours early over hot water, and a whopping full degree east of where it actually was at 8 PM. UK had it at 83.5W and it was at 84.5 W per NHC! Shear is likely less there, too. Then, partially because of that too far east initialization, UK send him E of the Yucatan! So, that is another reason why it has him so strong. Can anyone think of a reason that this run shouldn't be thrown in the trash?

The thing is, some ensemble guidance I have seen also shows a track east of the Yucatan. The initial intensity is accurate based upon the aircraft data

But it is starting out 60 miles E of reality, which makes it much easier to miss the Yucatan and puts it in a better environment. You talk about throwing out the GFS and maybe for good reason, but why not also throw something that initializes a very crucial 60 miles too far east?

[CrazyC83]

MET OFFICE TROPICAL CYCLONE GUIDANCE FOR NORTH-EAST PACIFIC AND ATLANTIC

GLOBAL MODEL DATA TIME 0000UTC 06.10.2017

TROPICAL STORM NATE ANALYSED POSITION : 15.3N 83.5W

ATCF IDENTIFIER : AL162017

LEAD CENTRAL MAXIMUM WIND
VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)
-------------- ---- -------- ------------- -------------
0000UTC 06.10.2017 0 15.3N 83.5W 999 39
1200UTC 06.10.2017 12 18.5N 84.7W 993 40
0000UTC 07.10.2017 24 21.9N 86.5W 990 46
1200UTC 07.10.2017 36 25.6N 89.1W 983 56
0000UTC 08.10.2017 48 28.2N 90.0W 976 59
1200UTC 08.10.2017 60 30.8N 88.3W 971 52
0000UTC 09.10.2017 72 34.3N 85.0W 984 30
1200UTC 09.10.2017 84 37.7N 79.9W 996 24
0000UTC 10.10.2017 96 40.5N 73.8W 1001 39
1200UTC 10.10.2017 108 42.0N 69.1W 1004 35

UKMET much stronger

There's a big initialization problem with UK and that has a lot to do with how strong it is and how far east its track is. First of all, it already had it just going offshore at 0Z (8 PM), or 4 hours early over hot water, and a whopping full degree east of where it actually was at 8 PM. UK had it at 83.5W and it was at 84.5 W per NHC! Shear is likely less there, too. Then, partially because of that too far east initialization, UK send him E of the Yucatan! So, that is another reason why it has him so strong. Can anyone think of a reason that this run shouldn't be thrown in the trash?

The thing is, some ensemble guidance I have seen also shows a track east of the Yucatan. The initial intensity is accurate based upon the aircraft data

Most of the eastern runs (i.e. those that hit well to the east of NOLA) do not go over, or just scrape, the Yucatan.