Reanalysis questions

[Hurricane Jed]

There won't likely be any upgrades for the early 1940's due to World War II. There weren't all that many observations, available, so what we have is it. That preliminary paper from 44-53 also downgraded the 1947 Fort Lauderdale hurricane, IIRC, meaning there might not have been any Category 5 hurricanes in the 1940s.

By the way, on no basis of science or anything ( ) I think Faith will be considered extratropical as of September 4th, as that was the last day it has a pressure listed in HURDAT.

I believe you are right. Looking back at the storms, a lot of them don't have a listed pressure and those that do the wind speed/Category for them seems high so probable downgrades. Great Atlantic Hurricane had the lowest pressure at 943 mb.

[Hurricanehink]

There won't likely be any upgrades for the early 1940's due to World War II. There weren't all that many observations, available, so what we have is it. That preliminary paper from 44-53 also downgraded the 1947 Fort Lauderdale hurricane, IIRC, meaning there might not have been any Category 5 hurricanes in the 1940s.

Have a link to the paper in question? If so, I thank you in advance.

http://etd.library.miami.edu/theses/ava ... genF10.pdf - here it is, but I should warn you it's a thesis, so it isn't official. However, NOAA intends to use that as a basis for once they reach 1944-1953. The link you had didn't have all of the data that's here.

[Hurricane Jed]

I've never liked that paper for some reason. To me it seems rushed.

[HURAKAN]

btw, if you find any mistakes or any link related to the HURDAT website is not working, let me know! thanks!!

[Hurricane Jed]

For the rest of the 1930's what do you all think happens?

I think that 1936 could lose several storms,
1937 might also lose some storms,
1938 will gain a couple storms but the New England Hurricane loses Category 5 status,
1939 gains a couple storms.

Not basing this off anything just guessing.

[Ptarmigan]

I personally think Hattie was stronger than what was recorded.

[Hurricane Jed]

this is sort of off topic from what you said but do you or does anyone know if a satellite photo of Hattie exists? Or even a radar image?

[thegreatdr]

Just because a graduate student published a reanalysis paper with good documentation and reasoning does not mean it will be accepted as gospel, though it certainly helps the effort. The hurricane reanalysis committee will still sift through the data and see if any further adjustments are needed. Their pace lately has been to revise 5 years of TCs per year, which covers a significant amount of storms.

The search for assigned TC names might hold up 1949 or lead to an exclusion of the 1947-1948 names "found". I hope they're able to find the 1949 names somewhere.

[Hybridstorm_November2001]

Here is another interesting prelimianry reanalysis paper (Chris Landsea of the NHC is one of the authors), that deals with several interesting storms including the Great New England Hurricane of 1938 & Hurricane Hazel of 1954 -

http://www.aoml.noaa.gov/hrd/hurdat/10_US_hurricanes.pdf *

* warning requires PDF reader

[Hurricane Jed]

this going really far but since I think they intend to do reanalysis up to 1997. Hurricane Opal anyone think it gets an upgrade or remains a 4? Also what was officially Opal's lowest pressure? HURDAT lists 919mb in both easy to read and normal versions but I have seen 916mb as well. which one is correct?

[CrazyC83]

this going really far but since I think they intend to do reanalysis up to 1997. Hurricane Opal anyone think it gets an upgrade or remains a 4? Also what was officially Opal's lowest pressure? HURDAT lists 919mb in both easy to read and normal versions but I have seen 916mb as well. which one is correct?

916mb is correct as the lowest pressure (between synoptic times).

The highest flight-level winds were 152 kt in Opal, which supports 137 kt at the surface. However, since it went up and down so fast, I would keep it as a Category 4, although with a higher peak intensity of 135 kt.

[Hurricane Jed]

Thanks Crazy. This helps. Trying to create a database of my own that organizes storms by pressure and category.

[HurricaneAndrew86]

Hey, I just joined Storm2K. Just read through all your posts discussing the reanalysis. I'm surprised nobody has discussed the 1938 hurricane yet.

To answer some of your questions:
-I understand that the release of the reanalysis is progressing in order. Therefore, 1936-43 will be next. After that will be 1944-53.
-I looked at some of the data for Camille... my opinion is that it should stay a Cat 5 for MS landfall- but I'm guessing it will be lowered from 165 kt to about 145 kt. If I remember correctly, the 909 mb reading was measured about 6 nm from the landfall point and it might not have been a central pressure. Also, I saw a time lapse of WSR-57 radar images in the hours leading up to landfall- and they reveal the eyewall of Camille was contracting up to landfall. Those images along with earlier data suggest Camille was strengthening following a eyewall replacement cycle. All of the anemometers in the area with strongest winds were destroyed in Camille.

[Hurricane Jed]

welcome aboard. Well then lets discuss. I think the storm remains a Category 5, given where it developed and all and several other storms that have formed that far east have reached Category 5 intensity. Also its pressure is in the range of a Category 5 storm, especially if the ambient pressure were high at the time of peak intensity. Second I possibly wonder if this hurricane was a Category 4 at landfall. The storm did produce a gust of 186 m.p.h. These are just my thoughts though.

[Hybridstorm_November2001]

Hey, I just joined Storm2K. Just read through all your posts discussing the reanalysis. I'm surprised nobody has discussed the 1938 hurricane yet.

Some of the latest data on this storm is contained in the link I posted earlier -

http://www.aoml.noaa.gov/hrd/hurdat/10_ ... icanes.pdf *

* warning requires PDF reader

[HurricaneAndrew86]

HybridStorm,

I can tell you that I am aware of some significant changes to the 1938 hurricane that were discussed a few months ago and hopefully 1936-1940 will come out by the end of 2012. I believe that NHC is in the process of approving it. Here's a summary of what I think are some additional changes to the reanalysis of 10 US landfalling hurricanes paper:
-It should be kept as a Cat 5 during the time original HURDAT listed it as a Cat 5 because there is no evidence that those ship obs of pressures in the 940s were actually central pressures.
-For landfall, that paper says 105 kt for LI and 100 kt for the next landfall. This will likely be kept as is because an official 95 kt ob from Fishers Island, NY was obtained (it was very close to a 10m 1-min value). The next highest official wind ob was 76 kt from Block Island, which was 10 nm outside the right RMW.

If you use the current HURDAT, there are 5 Cat 3s for NY. And also there are a number of Cat 3s for RI, CT, and MA. I think in reality, the true number of Cat 3s in those states is really only about half as many as that are currently listed. But the 1938 hurricane was one that was actually a Cat 3. The reason it produced winds that strong is due to the fast forward motion. The central pressure at landfall was about 941 mb, and some have argued that they think it should be a high end Cat 2 after seeing some recent storms with low central pressures and low winds such as Irene and Igor.

Disclaimer: My comments are my personal views and do not represent the views of any company, agency, or organization.

[CrazyC83]

HybridStorm,

I can tell you that I am aware of some significant changes to the 1938 hurricane that were discussed a few months ago and hopefully 1936-1940 will come out by the end of 2012. I believe that NHC is in the process of approving it. Here's a summary of what I think are some additional changes to the reanalysis of 10 US landfalling hurricanes paper:
-It should be kept as a Cat 5 during the time original HURDAT listed it as a Cat 5 because there is no evidence that those ship obs of pressures in the 940s were actually central pressures.
-For landfall, that paper says 105 kt for LI and 100 kt for the next landfall. This will likely be kept as is because an official 95 kt ob from Fishers Island, NY was obtained (it was very close to a 10m 1-min value). The next highest official wind ob was 76 kt from Block Island, which was 10 nm outside the right RMW.

If you use the current HURDAT, there are 5 Cat 3s for NY. And also there are a number of Cat 3s for RI, CT, and MA. I think in reality, the true number of Cat 3s in those states is really only about half as many as that are currently listed. But the 1938 hurricane was one that was actually a Cat 3. The reason it produced winds that strong is due to the fast forward motion. The central pressure at landfall was about 941 mb, and some have argued that they think it should be a high end Cat 2 after seeing some recent storms with low central pressures and low winds such as Irene and Igor.

Disclaimer: My comments are my personal views and do not represent the views of any company, agency, or organization.

The 1938 storm looks like it will go down as 105 kt at landfall. Working to keep the intensity higher was the fact it was moving EXTREMELY fast, and those tend to put down stronger winds to the right side of the storm. On the left side, I don't think there were even any hurricane sustained winds...

The next most likely major north of NC was Carol in 1954. It had a pressure of 955, but was small and fast-moving. Outside the RMW, Block Island had sustained 87 kt winds, which supports a 100 kt intensity. Its best analog would probably be Juan in 2003 (85 kt/973mb in Nova Scotia). The other storms which are suspect majors I think were all Cat 2 (or even Cat 1).

[MiamiensisWx]

I personally think Hattie was stronger than what was recorded.

Is your judgment based upon any data you have personally seen? On 28 October about 2000Z, aircraft reported a central pressure of 956 mb along with an eye diameter of just 10 miles (9 nautical miles). As the system was then somewhat small and the movement not especially slow, the 110-kt intensity in HURDAT looks reasonable at that time. I do tend to agree that Hattie may have briefly been deeper than 920 mb on 30 October 1961. According to reconnaissance data, Hattie gradually deepened to 920 mb about 2200Z, when the eye was estimated at 22 miles (19 nautical miles) in diameter. At 2330Z, the eye on radar contracted to just 16 miles (14 nautical miles) wide, but then returned to 22 mi / 19 n mi as the pressure rose to 930 mb, more than twelve hours before landfall in Belize. The hurricane may have dipped below 920 mb between 2200Z and 2330Z. Of course, such an estimate is speculation. Clearly, Hattie was still equally intense at landfall, based upon measurements of 920-930 mb inside the center.

[CrazyC83]

I personally think Hattie was stronger than what was recorded.

Is your judgment based upon any data you have personally seen? On 28 October about 2000Z, aircraft reported a central pressure of 956 mb along with an eye diameter of just 10 miles (9 nautical miles). As the system was then somewhat small and the movement not especially slow, the 110-kt intensity in HURDAT looks reasonable at that time. I do tend to agree that Hattie may have briefly been deeper than 920 mb on 30 October 1961. According to reconnaissance data, Hattie gradually deepened to 920 mb about 2200Z, when the eye was estimated at 22 miles (19 nautical miles) in diameter. At 2330Z, the eye on radar contracted to just 16 miles (14 nautical miles) wide, but then returned to 22 mi / 19 n mi as the pressure rose to 930 mb, more than twelve hours before landfall in Belize. The hurricane may have dipped below 920 mb between 2200Z and 2330Z. Of course, such an estimate is speculation. Clearly, Hattie was still equally intense at landfall, based upon measurements of 920-930 mb inside the center.

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.org. For official information, please refer to the NHC and NWS products.

Based on all that data, my guess - unofficial - would be to change them as follows (red = revision):

AL091961, HATTIE, 20,
19611027, 1200, TS, 11.6N, 81.5W, 45, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19611027, 1800, TS, 12.0N, 81.6W, 55, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19611028, 0000, HU, 12.8N, 81.7W, 65, 991, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19611028, 0600, HU, 12.9N, 81.7W, 80, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19611028, 1200, HU, 13.5N, 81.6W, 95, 969, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19611028, 1800, HU, 14.1N, 81.5W, 100, 963, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19611029, 0000, HU, 15.0N, 81.4W, 110, 952, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19611029, 0600, HU, 16.1N, 81.2W, 105, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19611029, 1200, HU, 16.9N, 81.4W, 100, 963, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19611029, 1800, HU, 17.7N, 81.9W, 105, 958, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19611030, 0000, HU, 18.2N, 82.4W, 110, 956, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19611030, 0600, HU, 18.5N, 83.8W, 125, 942, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19611030, 1200, HU, 18.4N, 84.4W, 135, 929, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19611030, 1800, HU, 18.2N, 85.2W, 145, 921, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19611031, 0000, HU, 17.9N, 86.1W, 145, 920, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19611031, 0600, HU, 17.6N, 87.1W, 135, 927, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19611031, 1200, HU, 17.2N, 88.1W, 130, 930, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19611031, 1800, TS, 16.9N, 88.9W, 60, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19611101, 0000, TS, 16.6N, 89.6W, 55, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,
19611101, 0600, TS, 15.7N, 90.1W, 45, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999, -999,

[Ptarmigan]

Is your judgment based upon any data you have personally seen? On 28 October about 2000Z, aircraft reported a central pressure of 956 mb along with an eye diameter of just 10 miles (9 nautical miles). As the system was then somewhat small and the movement not especially slow, the 110-kt intensity in HURDAT looks reasonable at that time. I do tend to agree that Hattie may have briefly been deeper than 920 mb on 30 October 1961. According to reconnaissance data, Hattie gradually deepened to 920 mb about 2200Z, when the eye was estimated at 22 miles (19 nautical miles) in diameter. At 2330Z, the eye on radar contracted to just 16 miles (14 nautical miles) wide, but then returned to 22 mi / 19 n mi as the pressure rose to 930 mb, more than twelve hours before landfall in Belize. The hurricane may have dipped below 920 mb between 2200Z and 2330Z. Of course, such an estimate is speculation. Clearly, Hattie was still equally intense at landfall, based upon measurements of 920-930 mb inside the center.

Code: Select all

Date: 27 OCT-1 NOV 1961
Hurricane HATTIE
ADV  LAT   LON       TIME     WIND  PR  STAT
  1  11.60  -81.50 10/27/12Z   45     - TROPICAL STORM
  2  12.00  -81.60 10/27/18Z   55     - TROPICAL STORM
  3  12.80  -81.70 10/28/00Z   65   991 HURRICANE-1
  4  12.90  -81.70 10/28/06Z  100     - HURRICANE-3
  5  13.50  -81.60 10/28/12Z  105   991 HURRICANE-3
  6  14.10  -81.50 10/28/18Z  110   969 HURRICANE-3
  7  15.00  -81.40 10/29/00Z  110   952 HURRICANE-3
  8  16.10  -81.20 10/29/06Z  110     - HURRICANE-3
  9  16.90  -81.30 10/29/12Z  110   963 HURRICANE-3
 10  17.70  -81.90 10/29/18Z  110     - HURRICANE-3
 11  18.20  -82.40 10/30/00Z  115   956 HURRICANE-4
 12  18.50  -83.80 10/30/06Z  120   942 HURRICANE-4
 13  18.40  -84.10 10/30/12Z  130   937 HURRICANE-4
 14  18.20  -85.20 10/30/18Z  140     - HURRICANE-5
 15  17.90  -86.10 10/31/00Z  140   920 HURRICANE-5
 16  17.60  -87.10 10/31/06Z  140     - HURRICANE-5
 17  17.20  -88.10 10/31/12Z  120   930 HURRICANE-4
 18  16.90  -88.90 10/31/18Z   60     - TROPICAL STORM
 19  16.60  -89.60 11/01/00Z   55     - TROPICAL STORM
 20  15.70  -90.10 11/01/06Z   45     - TROPICAL STORM

http://weather.unisys.com/hurricane/atl ... /track.dat

As for stronger, I said stronger than the recorded 140 knots, which i think probably peaked at 145 to 150 knots. Also, it was a late season storm as the ambient pressure tends to be higher.

The Hurricane Season of 1961
http://docs.lib.noaa.gov/rescue/mwr/090 ... 3-0107.pdf


As for Carla, I am not too sure if the 936 millibars and 175 mph matches as it was a large hurricane in the Gulf of Mexico.

This re-analysis shows Carla with a central pressure of 936 millibars with top winds of 91 knots.
[img]ftp://ftp.aoml.noaa.gov/hrd/pub/hwind/Operational/1961/AL031961/0911/0000/AL031961_0911_0000_contour08.png[/img]

I am sure that Carla was a major hurricane at the time as it produced major hurricane force winds in Texas. Not sure why the 91 knots.