Tropical Storm 18E

Passive Microwave (PMW) Intensity Information
Advanced Dvorak Technique
Version 9.1


       --Overpass--              --ARCHER--   Ring  Ring            Eye              BT   -Forecast-  
       Date    Time      Sat     Lat    Lon   Diam   Pct  TbDiff   Score  Meaning   Vmax  Lat    Lon                 
     20231022 223745  SSMISF18   10.4  -96.9   257   N/A    2.51   -2.51      N/A   35.0  10.4  -96.9 Analysis Plot     
     20231022 223747  SSMISF18   10.4  -96.9   235   N/A    2.24   -2.24      N/A   35.0  10.4  -96.9 Analysis Plot     
     20231023 124118  SSMISF17   11.9  -97.2   135    1%    4.10   -4.10      N/A   40.0  11.8  -97.2 Analysis Plot     
     20231023 193005     AMSR2   12.8  -97.4   246   26%    5.04   -5.04      N/A   40.0  12.4  -97.7 Analysis Plot     
     20231023 222457  SSMISF18   13.4  -97.7   135   11%    2.58   -2.58      N/A   45.0  13.3  -97.7 Analysis Plot     
     20231024 005926       GMI   13.4  -97.7   N/A   N/A     N/A     N/A      N/A   45.0  13.6  -97.7 Analysis Plot     
     20231024 122511       GMI   14.3  -99.0    23   97%   19.55  -34.55      N/A   50.0  14.5  -98.7 Analysis Plot     
     20231024 201256     AMSR2   15.3  -99.5    23  100%   65.51   80.51  >85 kts  100.0  15.4  -99.5 Analysis Plot     
     20231024 221227  SSMISF18   15.6  -99.8    12  100%   50.99   65.99  >85 kts  100.0  15.5  -99.6 Analysis Plot     
     20231025 000502  SSMISF16   15.8  -99.6    12  100%   44.37   59.37  >65 kts  100.0  15.8  -99.6 Analysis Plot     
     20231025 011957  SSMISF17   16.0  -99.3    12  100%   47.66   62.66  >85 kts  125.0  15.9  -99.7 Analysis Plot     
     20231025 082527     AMSR2   17.0 -100.3    23  100%   12.26   27.26  >65 kts  145.0  17.4 -100.2 Analysis Plot     
     20231025 104657  SSMISF18   17.1 -100.2    57   33%    0.08    0.08      N/A  145.0  17.7 -100.3 Analysis Plot     
     20231025 123929  SSMISF16   17.9 -100.4   N/A   N/A     N/A     N/A      N/A   95.0  17.9 -100.4 Analysis Plot

Legend

  - Overpass Date/Time are determined from satellite overpass of targeted TC (position determined from Best Track Lat/Lon position). Date is YYYYMMDD and time in HHMMSS (UTC).

  - Forecast (Best Track) and ARCHER positions (deg) of the TC center at overpass day/time. Positive/Negative: Latitude = North/South Hemisphere; Longitude = Eastern/Western Hemisphere.

  - BT Vmax is the concurrent ATCF Best Track (BT) wind speed intensity estimate (Vmax) value from either NOAA/National Hurricane Center (NHC) (North Atlantic and Northeast Pacific), NOAA/Central Pacific Hurricane Center (CPHC) (North-central Pacific) or Joint Typhoon Warning Center (JTWC) (Northwest Pacific, Indian Ocean, or Southwest Pacific).

  - Sat is the satellite descriptor providing the overpass. Currently the satellites used are the DMSP/SSMIS-16/17/18, GPM/GMI, and GCOM/AMSR2.

  - Ring Diam (km) indicates the estimated surface eyewall diameter if one is analyzed in the PMW imagery. The value listed is the average PMW-estimated inner eyewall edge diameter minus 10 km for eyewall slope. N/A indicates no appreciable eyewall is analyzed.

  - Ring Pct is the percentage of the analyzed "ring" (eyewall inner boundary) that is 1) colder than the eye Tb (the "hot spot" -- warmest eye pixel) by at least 20K, or 2) that is colder than 232K and colder than the eye Tb by 10K, whichever is greater. Values are red if Ring % ≤65,yellow/brown if Ring % ≤85 and green if Ring % >85. N/A indicates no appreciable eyewall is analyzed. A value over 85% is used in the intensity score by adding 15 points to it.

  - TbDiff is the difference between the warmest eye pixel and the warmest pixel on the eyewall. This value is used in the Intensity Score. N/A indicates no appreciable eyewall is analyzed.

  - Eye Score values are based on the strength and organization of the convective/eyewall signatures in the PMW imagery, and based on the ARCHER center location. They normally range from 0 to 100 with empirically-determined thresholds related to intensity (Vmax) in the "Meaning" column (≥20 suggests ≥65kts; ≥60 suggests ≥85kts). Scores are listed as negative, and not used by the ADT, when the NHC, CPHC, or JTWC Best Track Vmax is <55 kts in order to filter out occasional "false eye" cases. A value of -920 is used when the warmest eye pixel is <200K to prevent false positives; -930 means edge of overpass and <85% of eyewall is captured and therefore can't fully be analyzed.