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ncforecaster89

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About ncforecaster89

  • Birthday 05/03/1970

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  • Four Letter Airport Code For Weather Obs (Such as KDCA)
    KILM
  • Gender
    Male
  • Location:
    Wilmington, NC
  • Interests
    Hurricanes and blizzards are my primary interests relative to a specific atmospheric phenomenon. Tropical meteorology was, and has been, my focus since my first hurricane experience at the impressionable age of 14. It was this fateful encounter that led me to pursue a degree in atmospheric sciences. While in college, I was most fortunate to have interned at the NHC (by way of a student internship) with the late Bob Case as a mentor. Although I no longer work in the meterological field professionally, I still enjoy helping others by sharing the knowledge others have so generously given me. Thus, one is most likely to see the vast majority of my posts being centered on tropical meterology.

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  1. ncforecaster89

    Hurricane Barry

    It's highly likely the result of frictional convergence that often times helps tighten up the circulation after a TC crosses the coastline. Especially ones like Barry.
  2. ncforecaster89

    SNE "Tropical" Season Discussion 2019

    Actually, the NHC best track committee reduced the landfall intensity to 95 kt in MA, in their reanalysis. It's conceivable it was still a Cat 3 at landfall, but it has officially been reanalyzed to an upper-end Cat 2...borderline 3. https://www.aoml.noaa.gov/hrd/hurdat/UShurrs_detailed.html
  3. ncforecaster89

    SNE "Tropical" Season Discussion 2019

    Will this be the year?: A common refrain I presume is often heard across the North East coastal states during this time of year. Rightfully so, as it's just simply a matter of time before SNE receives another direct hurricane landfall, or strike, upon its shores. Based on the official HURDAT2 record (dating back to 1851), the statistical return period for a direct hurricane landfall is once every 10 years. Consequently, SNE is well overdue for just such an event, given it last occured in 1991. The same applies for a major hurricane (MH) landfall, with a return rate of 56 years, that last took place in 1954. Of course, we all understand that these statistics don't neccesitate that a hurricane will make a landfall within the aforementioned calculated return intervals. Case in point, three out of the four hurricane seasons between 1893 and 1896 had a direct hurricane landfall somewhere in SNE. Ironically, it was immediately followed by an astonishing 38 year gap between direct landfalls (1896 to 1934). It's also interesting to note that two different seasons in the aforementioned historical record (1869 & 1954) produced multiple SNE landfalls; each containing both a category-three and a category-two hurricane. Ultimately, the right atmospheric and oceanic conditions will conspire to add yet another SNE hurricane landfall to the historical record and, in doing so, answering the original question in the affirmative! New England hurricane landfalls (1851-2018): 1858 Cat 1/2 (Storm 3) * 1869 Cat 3 (Storm 3) 1869 Cat 2 (Storm 10) 1879 Cat 1 (Storm 2) 1893 Cat 1 (Storm 4) 1894 Cat 1 (Storm 5) 1896 Cat 1 (Storm 2) 1924 Cat 1 (Storm 3) # 1934 Cat 1 (Storm 7) 1938 Cat 3 (Storm 6) 1944 Cat 2 (Storm 7) 1954 Cat 3 (Carol) 1954 Cat 2/3 (Edna) 1960 Cat 2 (Donna) 1969 Cat 1 (Gerda) 1976 Cat 1 (Belle) 1985 Cat 1 (Gloria) 1991 Cat 2 (Bob) 2012 Cat 1 (Sandy) # * Likely underestimated in reanalysis. # No direct landfall, but still delivered HF winds. Totals and return intervals of each: 19 H strikes (8.8 years) 17 Landfalls (9.9 years) 3 MHs (56.0 years) 9 Cat 2 or 3 (18.7 years)
  4. 15/7/3 May 1/0/0 June 1/0/0 July 2/1/0 August 3/2/1 September 4/3/1 October 3/1/1 November/December 1/0/0
  5. ncforecaster89

    Major Hurricane Michael

    I'm still a little confused as to why/how the authors of the TCR chose to retain the operational pressure of 919 mb. The data they referenced for their decision argues for a slightly lower pressure at landfall. Here's their reasoning from the Report: "Michael’s minimum and landfall pressure is assessed at 919 mb based mainly on three data points: 1) a dropsonde measured pressure of 922 mb with a surface wind of 34 kt at 1558 UTC 10 October, 2) a pressure of 920.2 mb measured at the FCMP T3 tower at 1713 UTC 10 October, and 3) a pressure of 922.4 mb and simultaneous hurricane-force winds at the Tyndall AFB station at 1720 UTC 10 October." The first data point they reference is a measurement equivalent to 919 mb...at a full hour and a half prior to landfall. Since Michael was continuing to rapidly intensify during the subsequent 90 minutes thereafter, this observation suggests a pressure around 916 mb may be more accurate. The second data point referenced a lowest pressure of 920 mb measured in the eye...but not in the center. This suggests a lowest pressure estimate around 918 mb. The third data point of a 922 mb measured with accompanying hurricane-force winds would equate to an estimated pressure as low as 915-916 mb. Based on these data, the absolute minimum pressure located anywhere inside Michael's eye was likely in the 916-918 mb range. I'd had settled on 917 mb, myself...but no higher than 918 mb. '
  6. You're reading my mind, as those are precisely the top candidates for most likely category-five hurricanes USA landfalls whose intensity was underestimated. Those aside, others listed in the early HURDAT2 records could've been underestimated due to lack of data, as well. The 1846 hurricane is one that has always fascinated me as a probable category five. Edit: Just realized the typo for the date of the hurricane referenced in the last sentence (meant the 1846 hurricane; not 1842).
  7. Given that the majority of major hurricanes develop in the western Caribbean, during the month of October, the warm phase of the ENSO cycle is most influential in suppressing such activity...while the cool or neutral phase doesn’t have as profound of an effect. Moreover, the warm phase of the AMO is a significant driver of increased activity in the NATL basin throughout the season...to include the late season months of October and November. The beginning of the satellite era (1966 onward) is the point of delineation for me in determining the period whereby HURDAT2 is most reasonably accurate. Prior to that time, without satellite surveillance, it is a virtual certainty that many TCs (to include major hurricanes) went undetected, and many others’ intensity was likely underestimated; especially the further we go back in time. Of course, my definition of what characterizes being “reasonably accurate” might have a higher threshold than others...where some may consider the beginning of Recon flights in 1943, being a more reasonable standard in that regard. As you noted previously, more recent records indicate that the mainland USA experiences a category-five hurricane roughly every 30 years, on average. As such, it’s highly likely that there were additional category-five hurricane landfalls (at least 1 or 2) prior to the 1935 Great Labor Day hurricane...despite HURDAT2 showing no such occurrences for at least the 85 year period from 1851-1935.
  8. Hi Liberty! I’ve done a lot of statistical research into NATL basin activity via HURDAT2 and other historical sources. These records seem to indicate that the recent apparent increase of major hurricanes (MH) during the month of October isn’t that unusual or even anomalous. Here’s an overview of the known October MH activity in the NATL basin since 1851. It’s important to note that it’s highly likely...more like a certainty...that many other MHs are unaccounted for in the historical record prior to the satellite era, beginning in 1966. Moreover, it’s also most probable that a large number of the known hurricanes and major hurricanes likely had a higher peak intensity than presently listed in HURDAT2; especially the further it goes back in time. With that in mind, I’m also listing all the conservatively estimated 90 kt hurricanes from 1851-1910 and the 95 kt hurricanes from 1911-2000. The years highlighted in bold correspond to the seasons in which the strongest hurricane of that year occurred in either October or November (48 out of the 168 seasons since 1851). 1852 = 90 kt; 1853 = 90 kt; 1858 = 90 kt; 1859 = 110 kt; 1860 = 90 kt, 90 kt 1865 = 90 kt; 1866 = 120 kt; 1867 = 110 kt; 1868 = 90 kt, 90 kt; 1869 = 90 kt; 1870 = 100 kt, 90 kt, 90 kt; 1873 = 100 kt; 1874 = 90 kt (NOV); 1875 = 90 kt; 1876 = 90 kt, 100 kt; 1877 = 100 kt; 1878 = 120 kt, 100 kt, 90 kt; 1879 = 90 kt (NOV); 1880 = 120 kt; 1882 = 120 kt; 1884 = 90 kt; 1886 = 105 kt; 1887 = 90 kt; 1888 = 95 kt; 1893 = 105 kt, 115 kt; 1894 = 105 kt, 115 kt, 95 kt; 1895 = 90 kt; 1898 = 115 kt; 1899 = 95 kt; 1902 = 90 kt; 1905 = 105 kt; 1906 = 105 kt; 1908 = 95 kt, 90 kt; 1909 = 105 kt, 90 kt (NOV); 1910 = 130 kt; 1912 = 100 kt (NOV); 1916 = 105 kt, 95 kt; 1921 = 120 kt; 1922 = 95 kt; 1924 = 145 kt; 1926 = 130 kt; 1932 = 150 kt; 1933 = 110 kt; 1934 = 100 kt (NOV); 1939 = 120 kt; 1941 = 105 kt; 1942 = 95 kt (NOV); 1943 = 95 kt; 1944 = 125 kt; 1947 = 105 kt; 1948 = 110 kt; 1949 = 95 kt; 1950 = 95 kt, 100 kt, 115 kt; 1952 = 125 kt; 1954 = 115 kt; 1955 = 95 kt; 1959 = 105 kt; 1961 = 110 kt, 140 kt; 1962 = 95 kt, 100 kt; 1963 = 125, 95 kt; 1964 = 130 kt, 110 kt; 1966 = 130 kt; 1975 = 120 kt; 1985 = 105 kt (NOV); 1988 = 125 kt; 1994 = 95 kt (NOV); 1995 = 130 kt, 110 kt; 1996 = 100 kt; 1998 = 155 kt (NOV); 1999 = 95 kt, 135 kt (NOV); 2000 = 120 kt; 2001 = 125 kt, 120 kt (NOV); 2002 = 125 kt; 2003 = 110 kt; 2005 = 160 kt, 100 kt; 2008 = 115 kt, 125 kt (NOV); 2011 = 120 kt, 100 kt; 2012 = 100 kt; 2014 = 125 kt; 2015 = 135 kt; 2016 = 145 kt, 120 kt, 100 kt; 2017 = 100 kt; 2018 = 140 kt. As can be ascertained from these data, the seemingly increases in late-season/October MH frequency is more the result of much improved detection and verification of such storms, as well as a recency bias. The biggest takeaway for me is the realization that a very significant number of NATL basin major hurricanes occur after 9/30.
  9. That's definitely a borderline case as the max FLWs were 117 kt, which corresponds to 105 kt at the surface. The satellite intensity estimates were the equivalent of 115 kt...so they went with a compromise between the two. Given the continued drop of the central pressure from 936 to 934 mb following the aforementioned RECON ob, it's certainly possible...if not likely, it achieved Cat 4 right before landfall.
  10. Listed below are a few NATL basin hurricanes whose current HURDAT2 intensity estimates merits a revision. 1) Hurricane Charley (2004): Suggest a 135 kt MAX intensity for first SW FL landfall. Based on a 148 kt 700 mb FLW measured by RECON, its rapid intensification, small contracting eye, and tiny RMW (at the time of landfall at Cayo Costa, FL)...a revised intensity of 135 kt (up from 130 kt) is most applicable. 2) Hurricane OPAL (1995): Suggest a 140 kt MAX intensity in N central GOM (1000z/4th). Based on a 152 kt 700 mb FLW measured by RECON, its rapid intensification to 916 mb, small contracting eye, and compact RMW (about 12 hours prior to landfall in the NW FL Panhandle), it's highly likely Opal achieved a peak intensity of 140 kt and category-five on the SSHWS (up from 130 kt). 3) Hurricane Marilyn (1995): Suggest a 100 kt/CAT 3 intensity for St. Thomas, USVI. It's highly likely that Marilyn was a 100 kt category-three hurricane (up from 95 kt) when it blasted St. Thomas, USVI with its NE eyewall. At the time, RECON measured 700 mb FLWs between 105-110 knots, while the hurricane was undergoing a period of rapid intensification. Moreover, the official ASOS at the airport in St. Thomas recorded two-minute sustained winds of 90 kts. Given these data, it's most probable that even stronger winds impacted the immediate shoreline at that time of Marilyn's closest approach and greatest impact (0430z/16th). References: NHC Tropical Cyclone Reports for each respective hurricane shown above. https://www.nhc.noaa.gov/data/tcr/index.php?season=1995&basin=atl
  11. ncforecaster89

    Major Hurricane Michael

    I agree that it's conceivable that Andrew may have had a higher MSW than the current 145 kt value assigned for its SE Fl landfall. If so, it's unlikely that those top winds exceeded 150 kt (175 mph). The highest 700 mb FLW was measured at 162 kt...which corresponds to 146 kt at the surface using standard conversion rates. Considering it was still rapidly intensifying through landfall, 150 kt is most certainly plausible. But, as Calderon noted, much of the worst structual damage consisted of obliterated mobile home parks...which helps magnify the severity of the wind damage in comparison with the other modern category five hurricanes. Another recent S FL hurricane that I personally think should have its landfalling intensity increased would be hurricane Charley from 2004. The peak 700 mb FLW was 148 kt measured just before its first SW FL landfall...which equates to 133 kt surface winds. Given it's very tiny RMW, continued rapid intensification, and the aforementioned FLW winds, I'd suggest 135 kt (155 mph) is a more applicable intensity estimate.
  12. ncforecaster89

    Major Hurricane Michael

    It’s conceivable that Michael attained 145 kt...as noted in the Report by Doppler radar velocity data, but I don’t see any data that argues for a higher intensity than that...unless that 152 kt SFMR reading is reliable. The rest of the data supports 140-145 kt, and I’m cool with the 140 kt intensity baring verification of the aforementioned SFMR. EDIT: Should add that I think the Report still needs to revise the central pressure at landfall. Likely was in the 916-918 mb range.
  13. ncforecaster89

    Major Hurricane Michael

    Guess everyone already knows how I feel about this important development! What I found most interesting are these passages from the TCR: "It should be noted that future revisions to the Florida landfall intensity are possible, as additional re-assessment is expected once the research on the reliability of the SFMR at these high wind speeds is complete." "The maximum real-time surface wind estimate from the SFMR was 138 kt in the south eyewall at 1706 UTC that day. However, there were missing SFMR data in the real-time transmission during that penetration of the eyewall. Re-construction of the instrument’s raw brightness temperatures during the dropout period by the NOAA AOC indicates that the maximum 10-second SFMR wind estimate was 152 kt near 1707 UTC. The SFMR winds support an intensity greater than 135 kt, especially if the 152-kt value is correct and uncontaminated by wave shoaling in water about 89 ft deep. However, there is a significant caveat regarding the SFMR data, as experience during Hurricanes Irma, Jose, and Maria in 2017 suggests the possibility that the SFMR has a high bias at the wind speeds in question. Research to determine if this is the case is currently underway.
  14. ncforecaster89

    Major Hurricane Michael

    Not yet. The TCR for Florence hasn't been released, either. You can find all completed TCR's at the attached link...to include Michael's, once it's released to the public. https://www.nhc.noaa.gov/data/tcr/index.php?season=2018&basin=atl
  15. ncforecaster89

    Major Hurricane Michael

    Based on your official source, are you 100% certain the NHC has made this decision and that it’s simply a matter of public release? As myself and a few others have been arguing, adamantly, there’s no doubt the data you noted clearly corresponds to a 140 kt intensity. That said, I will still be very pleasantly surprised if they make that adjustment...mainly because of their reluctance to make such revisions in these cases (as made clear by former NHC forecaster, Todd Kimberlain). Must admit, for a second there, I kinda wondered if your post was made on April 1st?! If this indeed comes to pass as you stated, you have gathered the scoop of the year, hands down, IMHO. Thanks for sharing! Edit: I’m guessing it will be awhile longer before we see the Report given there are still 4 other TCR’s to be released, as well. Won’t be surprised if it’s the latter part of April or even into the month of May before they release the Michael TCR.
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