Tropical Depression 09W

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                 
     20250718 172830     AMSR2   19.8  120.9    46   14%    8.79   -8.79      N/A   40.0  20.0  121.3 Analysis Plot     
     20250718 220553  SSMISF17   20.3  120.3   N/A   N/A     N/A     N/A      N/A   45.0  20.1  119.8 Analysis Plot     
     20250719 064422       GMI   20.7  118.5   N/A   N/A     N/A     N/A      N/A   50.0  20.6  118.4 Analysis Plot     
     20250719 075051  SSMISF18   20.8  118.3   123    8%    4.84   -4.84      N/A   50.0  20.7  118.2 Analysis Plot     
     20250719 200842       GMI   21.6  115.4   112   50%    5.13    5.13      N/A   55.0  21.3  116.0 Analysis Plot     
     20250719 202246  SSMISF18   21.5  115.2   123   47%    6.82    6.82      N/A   55.0  21.6  115.1 Analysis Plot     
     20250720 104729  SSMISF17   22.2  112.5    90   22%    9.08    9.08      N/A   65.0  21.9  112.2 Analysis Plot     
     20250720 110100  SSMISF16   22.2  112.4    90   24%   15.32   15.32      N/A   65.0  21.9  112.1 Analysis Plot     
     20250720 185525     AMSR2   22.4  110.1   N/A   N/A     N/A     N/A      N/A   50.0  21.5  110.4 Analysis Plot     
     20250720 231836  SSMISF17   21.4  109.4   212   15%   16.92  -16.92      N/A   50.0  21.4  109.9 Analysis Plot     
     20250721 065345       GMI   21.9  108.3   N/A   N/A     N/A     N/A      N/A   45.0  21.3  108.5 Analysis Plot     
     20250721 090544  SSMISF18   21.6  108.5   N/A   N/A     N/A     N/A      N/A   45.0  21.2  108.7 Analysis Plot     
     20250721 104737  SSMISF16   22.3  107.8   N/A   N/A     N/A     N/A      N/A   45.0  21.1  108.4 Analysis Plot     
     20250722 061137       GMI   20.9  106.4   N/A   N/A     N/A     N/A      N/A   45.0  20.3  106.0 Analysis Plot     
     20250722 063153     AMSR2   20.5  106.5   N/A   N/A     N/A     N/A      N/A   35.0  20.3  105.8 Analysis Plot     
     20250722 085010  SSMISF18   20.7  105.9   N/A   N/A     N/A     N/A      N/A   35.0  20.3  105.8 Analysis Plot     
     20250722 101927  SSMISF17   20.7  105.7   190   N/A    1.56   -1.56      N/A   35.0  20.3  105.7 Analysis Plot     
     20250722 193614       GMI   19.9  104.1    90   N/A    1.23   -1.23      N/A   30.0  20.3  104.7 Analysis Plot     
     20250722 212220  SSMISF18   20.1  104.3   N/A   N/A     N/A     N/A      N/A   30.0  20.3  104.3 Analysis Plot     
     20250722 225131  SSMISF17   20.2  104.4   N/A   N/A     N/A     N/A      N/A   30.0  20.4  104.1 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.