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Re: Reanalysis questions

#321 Postby Hammy » Sun Jun 30, 2019 7:51 pm

:uarrow: That looks a lot better (and probably a lot easier to use/less resource-heavy) than Google Earth's database.

Since I'm in this thread, anybody have a clue when the 1964-70 (even if unofficial) report will be out? All that's out there is an abstract with a summary video for the period from 2016.
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Re: Reanalysis questions

#322 Postby GSBHurricane » Tue Jul 02, 2019 3:08 pm

Hammy wrote::uarrow: That looks a lot better (and probably a lot easier to use/less resource-heavy) than Google Earth's database.

Since I'm in this thread, anybody have a clue when the 1964-70 (even if unofficial) report will be out? All that's out there is an abstract with a summary video for the period from 2016.


I thought it was from 2018. But I see your point. Anyway, I really don’t know why they haven’t published the results yet, unless there was a case of several changes being rejected. Hopefully soon.
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Re: Reanalysis questions

#323 Postby GSBHurricane » Tue Jul 02, 2019 3:15 pm

Preliminary results show that 1969 basically stays the same so I wouldn’t be hung up too much about that year in particular. And there’s a leak of the 1964 reanalysis on Twitter. https://twitter.com/cyclonebiskit/statu ... 03648?s=21
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Re: Reanalysis questions

#324 Postby GSBHurricane » Wed Jul 03, 2019 11:36 am

GSBHurricane wrote:
Hammy wrote::uarrow: That looks a lot better (and probably a lot easier to use/less resource-heavy) than Google Earth's database.

Since I'm in this thread, anybody have a clue when the 1964-70 (even if unofficial) report will be out? All that's out there is an abstract with a summary video for the period from 2016.


I thought it was from 2018. But I see your point. Anyway, I really don’t know why they haven’t published the results yet, unless there was a case of several changes being rejected. Hopefully soon.


Update: They were reanalyzing Dora 1964 a couple weeks ago according to Twitter. Since the preliminary results were already revealed, I’m guessing they’re preparing the final results now.
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Re: Reanalysis questions

#325 Postby Ptarmigan » Sun Jul 07, 2019 1:25 pm

1900hurricane wrote:Regarding Joan '88, I created a plot from the 20th Century Reanalysis v2 dataset to estimate OCI and ROCI to use with KZC. For OCI, I have 1008 mb, and for ROCI, I have 285 nm. For storm speed, I took the distance between the 00Z and 06Z best track points and divided by six for the six hour average speed, which ended up being 6.83 kt. L is 11.9ºN from best track, and P is 932 mb also from best track. When all plugged into KZC, expected Vmax is a cool 130 kt even.

>>> from KZCeq import KZC, KZCroci
>>> p = 932
>>> c = 41 / 6
>>> c
6.833333333333333
>>> 9.5 * 30
285.0
>>> roci = 285
>>> l = 11.9
>>> oci = 1008
>>> p0 = 1000
>>> v = 100
>>> while p0 >= p:
v = v + 0.1
p0 = KZC(KZCroci(v, c, roci, l), oci)


>>> print('%3.0f' % v)
130


https://i.imgur.com/3XTYkUb.gif

I've been playing with the ROCI version of KZC a little bit, and for the most part it appears to match up very well with the TS wind radius version that is operationally used. It does diverge a little bit towards the 'windier' out beyond 155 kt or so, but not exceptionally so, and I actually prefer the ROCI version when it comes to weaker storms that sometimes have inconsistent wind radii. Naturally, I then pulled up some old surface charts of past storms and computed away. Here's a few that I did.

1900hurricane: p = 936, c = 13.8, roci = 250, l = 29.1, oci = 1009, v = 121 kt
(p = 931) v = 127 kt
Andrew '92: p = 922, c = 17.3, roci = 113, l = 25.5, oci = 1013, v = 148 kt
Celia '70: p = 945, c = 13.3, roci = 120, l = 27.6, oci = 1009, v = 114 kt
Camille '69: p = 900, c = 14.0, roci = 120, l = 30.3, oci = 1003, v = 156 kt
Carla '61: p = 931, c = 4.33, roci = 375, l = 28.0, oci = 1004, v = 114 kt


Interesting. How did you come with ROCI? It would be interesting to see how large other hurricanes were like the 1886 Indianola Hurricane.

I figured Carla is a large hurricane. The ROCI is much larger than Ike.
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Re: Reanalysis questions

#326 Postby CrazyC83 » Sun Jul 07, 2019 10:27 pm

The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or STORM2K. For official information, please refer to products from the National Hurricane Center and National Weather Service.

I've been looking again at more storms from the 1980s and early 1990s. Here's another one I decided to look at: Hurricane Alicia. Note the magenta positions are track changes, blue are new positions or lateral changes, red is stronger, green is weaker.

AL031983, ALICIA, 23,
19830815, 1200, , TD, 27.3N, 90.5W, 30, 1009, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19830815, 1800, , TS, 27.2N, 91.0W, 35, 1006, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19830816, 0000, , TS, 27.1N, 91.7W, 40, 1005, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19830816, 0600, , TS, 27.0N, 92.2W, 40, 1004, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19830816, 1200, , TS, 27.1N, 92.5W, 45, 1002, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19830816, 1800, , TS, 27.3N, 92.8W, 50, 997, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19830817, 0000, , TS, 27.4N, 93.3W, 55, 991, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19830817, 0600, , HU, 27.7N, 93.7W, 65, 987, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19830817, 1200, , HU, 27.9N, 94.2W, 70, 983, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19830817, 1800, , HU, 28.1N, 94.5W, 80, 974, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19830818, 0000, , HU, 28.4N, 94.8W, 80, 970, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19830818, 0600, , HU, 28.9N, 95.0W, 85, 963, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19830818, 0700, L, HU, 29.1N, 95.1W, 85, 962, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19830818, 1200, , HU, 29.7N, 95.5W, 70, 967, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19830818, 1800, , TS, 30.5N, 96.0W, 40, 987, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19830819, 0000, , TD, 31.5N, 96.7W, 30, 1000, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19830819, 0600, , TD, 32.4N, 97.4W, 25, 1005, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19830819, 1200, , TD, 33.3N, 98.0W, 20, 1008, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19830819, 1800, , TD, 34.4N, 98.5W, 25, 1009, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19830820, 0000, , TD, 35.4N, 99.0W, 20, 1010, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19830820, 0600, , TD, 36.5N, 99.4W, 20, 1011, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19830820, 1200, , TD, 37.6N, 99.2W, 20, 1011, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19830820, 1800, , TD, 38.9N, 99.0W, 20, 1011, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
(Removed last two points; absorbed by frontal zone at 0000Z)

Here's a storm that I believe the current status of a major hurricane will NOT hold up. In fact, most of the intensities are overdone. There isn't great data for part of its life over water in terms of wind, but a few strike me:

1) Genesis is unchanged (due to inconclusive data) but at about 08Z on August 16, the NOAA P-3 measured winds at 1,500' of 55 kt (perhaps the basis for the 50-55 kt intensity in HURDAT2 at that time). That would translate into winds of 40-45 kt at the most. Hence, those intensities were lowered from 50 and 55 to 40 and 45. Other intensities that day were also lowered in tandem.

2) The satellite imagery on August 16, and even early on August 17, was pretty lousy and did not scream hurricane. Used in tandem with the P-3 data, that suggests that Alicia took longer to become a hurricane, and even then barely so.

3) The HURDAT2 overestimation continued right up to landfall I believe. In the last 12 hours, the pressure continued to fall, to as low as 962 mb as extrapolated (which I accepted as the landfall pressure). However, the highest winds supported by Recon (the reliable P-3 too) were 99 kt - at the 850 level. That does NOT support a category 3 hurricane, and in fact you could argue as low as 75-80 kt. Dvorak at the time appeared to be T5.0 as well. While the P/W relationship may call for a higher intensity, you have to go with the reliable wind data.

4) Surface data also helps a lot. There was a pressure reading of 967 mb in Alvin, which was about 3 1/2 hours after landfall. Since it was still partially over water in the first couple hours before beginning a rapid deepening, the landfall pressure of 962 mb is retained. In addition, Houston Hobby Airport, just outside or near the fringe of the RMW, measured a sustained wind (over land, period unknown) of 71 kt. It was likely stronger over water. The wind damage to buildings in downtown Houston was similar to Ike, so the winds there were likely similar, except this time Houston was in the RFQ and near the edge of the RMW.

5) I don't see any indication that Alicia became extratropical; it might have lost its deep convection (hence a remnant low) but I have no higher-res satellite data at those times to confirm or deny such. However, it was long absorbed by a frontal zone at 12Z August 21, hence I moved up the decay time 12 hours.

Based on all that data, I estimate the landfall intensity of Alicia, with some uncertainty (+/- 5 kt), to be 85 kt. That is significantly lower than the current estimate and removes Alicia from the list of major hurricanes. However, I don't see any reliable data suggesting that it was a major. It should be a sign that a category 2 (or even category 1) hurricane can do very serious damage.
Last edited by CrazyC83 on Sun Jul 07, 2019 10:51 pm, edited 1 time in total.
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Re: Reanalysis questions

#327 Postby CrazyC83 » Sun Jul 07, 2019 10:37 pm

Regarding Joan, wow that was stronger than HURDAT looking at satellite, that would be knocking on the door of T7.5! 1988 was probably a feast-or-famine season and 2007 seems the perfect analog to it.
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Re: Reanalysis questions

#328 Postby 1900hurricane » Sun Aug 04, 2019 11:29 pm

Ptarmigan wrote:
1900hurricane wrote:Regarding Joan '88, I created a plot from the 20th Century Reanalysis v2 dataset to estimate OCI and ROCI to use with KZC. For OCI, I have 1008 mb, and for ROCI, I have 285 nm. For storm speed, I took the distance between the 00Z and 06Z best track points and divided by six for the six hour average speed, which ended up being 6.83 kt. L is 11.9ºN from best track, and P is 932 mb also from best track. When all plugged into KZC, expected Vmax is a cool 130 kt even.

>>> from KZCeq import KZC, KZCroci
>>> p = 932
>>> c = 41 / 6
>>> c
6.833333333333333
>>> 9.5 * 30
285.0
>>> roci = 285
>>> l = 11.9
>>> oci = 1008
>>> p0 = 1000
>>> v = 100
>>> while p0 >= p:
v = v + 0.1
p0 = KZC(KZCroci(v, c, roci, l), oci)


>>> print('%3.0f' % v)
130


https://i.imgur.com/3XTYkUb.gif

I've been playing with the ROCI version of KZC a little bit, and for the most part it appears to match up very well with the TS wind radius version that is operationally used. It does diverge a little bit towards the 'windier' out beyond 155 kt or so, but not exceptionally so, and I actually prefer the ROCI version when it comes to weaker storms that sometimes have inconsistent wind radii. Naturally, I then pulled up some old surface charts of past storms and computed away. Here's a few that I did.

1900hurricane: p = 936, c = 13.8, roci = 250, l = 29.1, oci = 1009, v = 121 kt
(p = 931) v = 127 kt
Andrew '92: p = 922, c = 17.3, roci = 113, l = 25.5, oci = 1013, v = 148 kt
Celia '70: p = 945, c = 13.3, roci = 120, l = 27.6, oci = 1009, v = 114 kt
Camille '69: p = 900, c = 14.0, roci = 120, l = 30.3, oci = 1003, v = 156 kt
Carla '61: p = 931, c = 4.33, roci = 375, l = 28.0, oci = 1004, v = 114 kt


Interesting. How did you come with ROCI? It would be interesting to see how large other hurricanes were like the 1886 Indianola Hurricane.

I figured Carla is a large hurricane. The ROCI is much larger than Ike.

I either take it from the best track files or (as in these cases), I estimate it myself via surface analyses or reanalysis data. 1º of latitude is the same as 60 nm, so it's fairly straightforward to do if you have a coordinate grid. Just take how 'tall' the storm is in degrees and multiply by 30 (60 nm in 1 degree, then divide by two to go from a diameter to a radius).
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Re: Reanalysis questions

#329 Postby 1900hurricane » Sun Aug 04, 2019 11:47 pm

Just for fun, I also decided to run both of my versions of KZC pressure to wind over CSU's enhanced best track data for Andrew '92 since it includes the operational wind radii and outermost closed isobar data. I did make a slight tweak to the data to include the landfall point at 09Z August 24th, which included the minimum 922 mb pressure, but that was easy to do since all the wind radii/oci data was the same as the 06Z and 12Z point. Both versions also net me a 148 kt expected Vmax.

Date & Time Lat/Lon Vmax(kt) Speed Mean Analyzed OCI
exp(act) (kt) R34 Pressure
------------------------------------------------------------------------
8/16/1992 18Z: 10.8N 35.5W 23 ( 25), 5, 0, 1010, 1011
8/17/1992 0Z: 11.2N 37.4W 34 ( 30), 19, 0, 1009, 1012
8/17/1992 6Z: 11.7N 39.6W 37 ( 30), 22, 0, 1008, 1012
8/17/1992 12Z: 12.3N 42.0W 42 ( 35), 24, 50, 1006, 1012
8/17/1992 18Z: 13.1N 44.2W 48 ( 35), 23, 50, 1003, 1012
8/18/1992 0Z: 13.6N 46.2W 49 ( 40), 20, 50, 1002, 1012
8/18/1992 6Z: 14.1N 48.0W 51 ( 45), 18, 50, 1001, 1012
8/18/1992 12Z: 14.6N 49.9W 53 ( 45), 19, 50, 1000, 1012
8/18/1992 18Z: 15.4N 51.8W 53 ( 45), 20, 50, 1000, 1012
8/19/1992 0Z: 16.3N 53.5W 51 ( 45), 19, 50, 1001, 1012
8/19/1992 6Z: 17.2N 55.3W 49 ( 45), 19, 50, 1002, 1012
8/19/1992 12Z: 18.0N 56.9W 43 ( 45), 17, 50, 1005, 1012
8/19/1992 18Z: 18.8N 58.3W 39 ( 45), 16, 50, 1007, 1012
8/20/1992 0Z: 19.8N 59.3W 30 ( 40), 14, 50, 1011, 1012
8/20/1992 6Z: 20.7N 60.0W 30 ( 40), 11, 50, 1013, 1015
8/20/1992 12Z: 21.7N 60.7W 26 ( 40), 12, 50, 1015, 1015
8/20/1992 18Z: 22.5N 61.5W 36 ( 40), 11, 50, 1014, 1020
8/21/1992 0Z: 23.2N 62.4W 33 ( 45), 11, 75, 1014, 1019
8/21/1992 6Z: 23.9N 63.3W 38 ( 45), 11, 75, 1010, 1018
8/21/1992 12Z: 24.4N 64.2W 39 ( 50), 10, 62, 1007, 1016
8/21/1992 18Z: 24.8N 64.9W 42 ( 50), 8, 62, 1004, 1016
8/22/1992 0Z: 25.3N 65.9W 50 ( 55), 10, 50, 1000, 1016
8/22/1992 6Z: 25.6N 67.0W 59 ( 65), 10, 62, 994, 1016
8/22/1992 12Z: 25.8N 68.3W 78 ( 80), 12, 65, 981, 1016
8/22/1992 18Z: 25.7N 69.7W 94 ( 95), 13, 65, 969, 1016
8/23/1992 0Z: 25.6N 71.1W 104 (110), 13, 62, 961, 1016
8/23/1992 6Z: 25.5N 72.5W 121 (130), 13, 62, 947, 1016
8/23/1992 12Z: 25.4N 74.2W 136 (145), 15, 62, 933, 1014
8/23/1992 18Z: 25.4N 75.8W 147 (150), 14, 90, 922, 1014
8/24/1992 0Z: 25.4N 77.5W 139 (125), 15, 90, 930, 1014
8/24/1992 6Z: 25.4N 79.3W 132 (130), 16, 98, 937, 1014
8/24/1992 9Z: 25.5N 80.3W 148 (145), 18, 98, 922, 1014
8/24/1992 12Z: 25.6N 81.2W 115 (115), 16, 98, 951, 1014
8/24/1992 18Z: 25.8N 83.1W 120 (115), 17, 98, 947, 1014
8/25/1992 0Z: 26.2N 85.0W 125 (115), 18, 98, 943, 1014
8/25/1992 6Z: 26.6N 86.7W 117 (115), 16, 125, 948, 1014
8/25/1992 12Z: 27.2N 88.2W 119 (120), 15, 125, 946, 1014
8/25/1992 18Z: 27.8N 89.6W 124 (125), 14, 125, 941, 1014
8/26/1992 0Z: 28.5N 90.5W 127 (125), 11, 125, 937, 1014
8/26/1992 6Z: 29.2N 91.3W 106 (120), 10, 80, 955, 1014
8/26/1992 12Z: 30.1N 91.7W 83 ( 80), 10, 85, 973, 1014
8/26/1992 18Z: 30.9N 91.6W 55 ( 50), 8, 50, 991, 1014
8/27/1992 0Z: 31.5N 91.1W 48 ( 35), 7, 0, 995, 1014
8/27/1992 6Z: 32.1N 90.5W 45 ( 30), 8, 0, 997, 1014
8/27/1992 12Z: 32.8N 89.6W 44 ( 30), 10, 0, 998, 1014
8/27/1992 18Z: 33.6N 88.4W 20 ( 25), 13, 0, 0, 0
8/28/1992 0Z: 34.4N 86.7W 15 ( 20), 16, 0, 0, 0
8/28/1992 6Z: 35.4N 84.0W 15 ( 20), 24, 0, 0, 0
------------------------------------------------------------------------

Date & Time Lat/Lon Vmax(kt) Speed Mean Analyzed OCI
exp(act) (kt) ROCI Pressure
------------------------------------------------------------------------------
8/16/1992 18Z: 10.8N 35.5W 24 ( 25), 5, 125, 1010, 1011
8/17/1992 0Z: 11.2N 37.4W 35 ( 30), 19, 125, 1009, 1012
8/17/1992 6Z: 11.7N 39.6W 38 ( 30), 22, 120, 1008, 1012
8/17/1992 12Z: 12.3N 42.0W 43 ( 35), 24, 120, 1006, 1012
8/17/1992 18Z: 13.1N 44.2W 49 ( 35), 23, 120, 1003, 1012
8/18/1992 0Z: 13.6N 46.2W 50 ( 40), 20, 120, 1002, 1012
8/18/1992 6Z: 14.1N 48.0W 51 ( 45), 18, 120, 1001, 1012
8/18/1992 12Z: 14.6N 49.9W 54 ( 45), 19, 120, 1000, 1012
8/18/1992 18Z: 15.4N 51.8W 54 ( 45), 20, 120, 1000, 1012
8/19/1992 0Z: 16.3N 53.5W 52 ( 45), 19, 120, 1001, 1012
8/19/1992 6Z: 17.2N 55.3W 50 ( 45), 19, 120, 1002, 1012
8/19/1992 12Z: 18.0N 56.9W 44 ( 45), 17, 120, 1005, 1012
8/19/1992 18Z: 18.8N 58.3W 40 ( 45), 16, 120, 1007, 1012
8/20/1992 0Z: 19.8N 59.3W 31 ( 40), 14, 120, 1011, 1012
8/20/1992 6Z: 20.7N 60.0W 31 ( 40), 11, 120, 1013, 1015
8/20/1992 12Z: 21.7N 60.7W 29 ( 40), 12, 75, 1015, 1015
8/20/1992 18Z: 22.5N 61.5W 39 ( 40), 11, 75, 1014, 1020
8/21/1992 0Z: 23.2N 62.4W 36 ( 45), 11, 75, 1014, 1019
8/21/1992 6Z: 23.9N 63.3W 41 ( 45), 11, 75, 1010, 1018
8/21/1992 12Z: 24.4N 64.2W 41 ( 50), 10, 100, 1007, 1016
8/21/1992 18Z: 24.8N 64.9W 44 ( 50), 8, 100, 1004, 1016
8/22/1992 0Z: 25.3N 65.9W 52 ( 55), 10, 100, 1000, 1016
8/22/1992 6Z: 25.6N 67.0W 61 ( 65), 10, 100, 994, 1016
8/22/1992 12Z: 25.8N 68.3W 80 ( 80), 12, 100, 981, 1016
8/22/1992 18Z: 25.7N 69.7W 96 ( 95), 13, 100, 969, 1016
8/23/1992 0Z: 25.6N 71.1W 105 (110), 13, 125, 961, 1016
8/23/1992 6Z: 25.5N 72.5W 122 (130), 13, 125, 947, 1016
8/23/1992 12Z: 25.4N 74.2W 136 (145), 15, 125, 933, 1014
8/23/1992 18Z: 25.4N 75.8W 147 (150), 14, 125, 922, 1014
8/24/1992 0Z: 25.4N 77.5W 139 (125), 15, 125, 930, 1014
8/24/1992 6Z: 25.4N 79.3W 132 (130), 16, 125, 937, 1014
8/24/1992 9Z: 25.5N 80.3W 148 (145), 18, 125, 922, 1014
8/24/1992 12Z: 25.6N 81.2W 116 (115), 16, 125, 951, 1014
8/24/1992 18Z: 25.8N 83.1W 121 (115), 17, 125, 947, 1014
8/25/1992 0Z: 26.2N 85.0W 125 (115), 18, 150, 943, 1014
8/25/1992 6Z: 26.6N 86.7W 117 (115), 16, 180, 948, 1014
8/25/1992 12Z: 27.2N 88.2W 119 (120), 15, 160, 946, 1014
8/25/1992 18Z: 27.8N 89.6W 124 (125), 14, 160, 941, 1014
8/26/1992 0Z: 28.5N 90.5W 127 (125), 11, 160, 937, 1014
8/26/1992 6Z: 29.2N 91.3W 106 (120), 10, 160, 955, 1014
8/26/1992 12Z: 30.1N 91.7W 82 ( 80), 10, 160, 973, 1014
8/26/1992 18Z: 30.9N 91.6W 54 ( 50), 8, 180, 991, 1014
8/27/1992 0Z: 31.5N 91.1W 47 ( 35), 7, 180, 995, 1014
8/27/1992 6Z: 32.1N 90.5W 43 ( 30), 8, 180, 997, 1014
8/27/1992 12Z: 32.8N 89.6W 42 ( 30), 10, 180, 998, 1014
8/27/1992 18Z: 33.6N 88.4W 20 ( 25), 13, 0, 0, 0
8/28/1992 0Z: 34.4N 86.7W 15 ( 20), 16, 0, 0, 0
8/28/1992 6Z: 35.4N 84.0W 15 ( 20), 24, 0, 0, 0
------------------------------------------------------------------------------
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CrazyC83
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Re: Reanalysis questions

#330 Postby CrazyC83 » Mon Aug 05, 2019 10:54 pm

The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or STORM2K. For official information, please refer to products from the National Hurricane Center and National Weather Service.

Speaking of Andrew, I know it was reanalyzed in 2002. However, I think we have learned more in the last 17 years that I would revisit it again. Here are changes I would make.

AL041992, ANDREW, 54,
19920816, 1800, , TD, 10.8N, 35.5W, 25, 1010, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920817, 0000, , TD, 11.2N, 37.4W, 30, 1009, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920817, 0600, , TD, 11.7N, 39.6W, 30, 1008, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920817, 1200, , TS, 12.3N, 42.0W, 35, 1006, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920817, 1800, , TS, 13.1N, 44.2W, 35, 1003, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920818, 0000, , TS, 13.6N, 46.2W, 40, 1002, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920818, 0600, , TS, 14.1N, 48.0W, 45, 1001, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920818, 1200, , TS, 14.6N, 49.9W, 45, 1000, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920818, 1800, , TS, 15.4N, 51.8W, 45, 1000, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920819, 0000, , TS, 16.3N, 53.5W, 45, 1001, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920819, 0600, , TS, 17.2N, 55.3W, 45, 1002, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920819, 1200, , TS, 18.0N, 56.9W, 45, 1005, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920819, 1800, , TS, 18.8N, 58.3W, 45, 1007, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920820, 0000, , TS, 19.8N, 59.3W, 50, 1011, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920820, 0600, , TS, 20.7N, 60.0W, 50, 1013, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920820, 1200, , TS, 21.7N, 60.7W, 45, 1015, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920820, 1800, , TS, 22.5N, 61.5W, 45, 1014, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920821, 0000, , TS, 23.2N, 62.4W, 50, 1014, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920821, 0600, , TS, 23.9N, 63.3W, 50, 1010, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920821, 1200, , TS, 24.4N, 64.2W, 50, 1007, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920821, 1800, , TS, 24.8N, 64.9W, 50, 1004, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920822, 0000, , TS, 25.3N, 65.9W, 55, 1000, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920822, 0600, , HU, 25.6N, 67.0W, 65, 994, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920822, 1200, , HU, 25.8N, 68.3W, 80, 981, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920822, 1800, , HU, 25.7N, 69.7W, 100, 969, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920823, 0000, , HU, 25.6N, 71.1W, 115, 957, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920823, 0600, , HU, 25.5N, 72.5W, 130, 945, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920823, 1200, , HU, 25.4N, 74.2W, 145, 933, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920823, 1800, , HU, 25.4N, 75.8W, 155, 922, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920823, 2100, L, HU, 25.4N, 76.6W, 150, 925, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920824, 0000, , HU, 25.4N, 77.5W, 140, 928, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920824, 0100, L, HU, 25.4N, 77.8W, 140, 931, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920824, 0400, I, HU, 25.4N, 78.7W, 140, 938, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920824, 0600, , HU, 25.4N, 79.3W, 145, 935, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920824, 0840, L, HU, 25.5N, 80.2W, 150, 926, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920824, 0905, L, HU, 25.5N, 80.3W, 155, 922, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920824, 1200, , HU, 25.6N, 81.2W, 120, 947, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920824, 1800, , HU, 25.8N, 83.1W, 110, 946, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920825, 0000, , HU, 26.2N, 85.0W, 115, 943, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920825, 0600, , HU, 26.6N, 86.7W, 115, 948, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920825, 1200, , HU, 27.2N, 88.2W, 120, 946, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920825, 1800, , HU, 27.8N, 89.6W, 125, 939, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920825, 2100, I, HU, 28.1N, 90.1W, 125, 936, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920826, 0000, , HU, 28.5N, 90.5W, 120, 940, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920826, 0600, , HU, 29.2N, 91.3W, 110, 952, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920826, 0830, L, HU, 29.6N, 91.5W, 100, 958, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920826, 1200, , HU, 30.1N, 91.7W, 80, 976, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920826, 1800, , TS, 30.9N, 91.6W, 50, 989, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920827, 0000, , TS, 31.5N, 91.1W, 35, 995, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920827, 0600, , TD, 32.1N, 90.5W, 30, 997, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920827, 1200, , TD, 32.8N, 89.6W, 30, 998, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920827, 1800, , TD, 33.6N, 88.4W, 25, 999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920828, 0000, , TD, 34.4N, 86.7W, 20, 1000, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19920828, 0600, , TD, 35.4N, 84.0W, 20, 1000, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,

* No changes are made before August 19 at 1200Z, which is entirely based on satellite estimates. Given the structural changes later, there is no value in assuming different intensities earlier in the life relative to Dvorak estimates.
* Despite the incredibly high pressures late on August 19 and especially August 20, amazingly, the Recon data supports higher intensities. There were two reports of FL winds around 70 kt (at 1,500 ft, which would support 53 kt at the surface). It is likely that Andrew was embedded in a ridge with an extremely high environmental pressure. I went up with the intensities that day. You could also make an argument for a remnant low classification at times, but I didn't go that far.
* The structure changed again on August 21 and Andrew took off like a rocket. Minor changes are made on the run up to peak intensity as Andrew explosively intensified on August 22. The initial peak of 150 kt is increased to 155 kt based on the 170 kt FL winds.
* A land station at Harbour Island in the Bahamas measured 120 kt at an unknown time period (likely 10 minutes?). However, it maxed out the instrument and may not have come close to measuring the maximum intensity. The pressure rose as high as 938 or so at about 0400Z (non-synoptic point added), perhaps due to an ERC, however, the wind speeds did not decrease much (if at all) and even the wind data when pressures were in the 930s supported cat 5 intensity. Given the tight gradient, later Recon data and modest change in the appearance, I believe it remained a category 5 hurricane throughout the Bahamas.
* Andrew was bombing out in the last few hours before Florida landfall. The 162 kt FL winds (supporting 146 kt at the surface with the standard 90% factor) occurred at 0810Z, about an hour before landfall, but in that time the pressure dropped from about 932 to 922 in just the last hour. It is also likely that 90% was a low estimate for a conversion factor (as we have seen with the SFMR with bombing storms) and H*WIND had 153 kt. All those factors lend me to a landfall intensity estimate of 155 kt (+/- 5 kt).
* While I believe it weakened a bit more before reaching the Gulf, the intensities in the eastern and central Gulf are largely unchanged from the last reanalysis. The Gulf peak of 125 kt is retained, supported by a FL wind around 140 kt. A non-synoptic point at 2100Z is added to better indicate the relative peak in the Gulf.
* The weakening trend was likely not nearly as abrupt as shown in HURDAT2 approaching Louisiana landfall. The 100 kt landfall intensity I left alone.
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