Topic: Termination of Satellite Analysis Branch’s Manual Dvorak Estimates
Date/Time Issued: July 10, 2026 1400 UTC
Product(s) or Data Impacted: Manual Dvorak Estimates for the South Pacific (TXPQ20 KNES - TXPQ29 KNES), Northwest Pacific (TXST20 KNES - TXST29 KNES), and North Indian Ocean (TXPS20 KNES - TXPS29 KNES)
Date/Time of Initial Impact: September 8, 2026 0000 UTC
Date/Time of Expected End: NA (Termination of Product)
Length of Impact: NA
Details/Specifics of Change:
Originally developed by Vernon Dvorak between 1969 and 1984, this manual technique is used to determine tropical cyclone intensity—including tropical depressions, tropical storms, and major typhoons or hurricanes—relying solely on visible and infrared satellite imagery.
This serves as the 60-day notice that the generation of manual Dvorak estimates by the Satellite Analysis Branch for the South Pacific, Northwest Pacific, and North Indian Ocean will be discontinued effective September 10, 2026. Users are advised to transition to alternative estimates provided by NOAA’s National Weather Service, the Department of War (DOW), and other Regional Specialized Meteorological Centers (RSMCs).
Please refer to the information below for details on where to obtain alternative Dvorak estimates:
| Basin | Continuing Sources of Dvorak Estimates |
South Pacific SAB planned termination date of September 8, 2026 | JTWC, RSMC Nadi, RSMC Honolulu (CPHC), TCWC Darwin, TCWC Brisbane, TCWC Port Moresby, TCWC Wellington |
South Indian SAB terminated Dvorak estimates on July 1, 2025 | Continuing Sources of Dvorak Estimates: JTWC, RSMC La Reunion, RSMC New Delhi, TCWC Perth, TCWC Darwin, TCWC Jakarta |
North Indian SAB planned termination date of September 8, 2026 | JTWC, RSMC New Delhi |
West Pacific SAB planned termination date of September 8, 2026 | JTWC, RSMC Tokyo, RSMC New Delhi, Taiwan Weather Bureau |
Central Pacific SAB terminated Dvorak estimates on May 10, 2026 | RSMC Honolulu (CPHC), JTWC |
East Pacific SAB terminated Dvorak estimates on May 10, 2026 | Tropical Analysis and Forecast Branch (NOAA/NWS/National Hurricane Center) |
North Atlantic SAB terminated Dvorak estimates on May 10, 2026 | Tropical Analysis and Forecast Branch (NOAA/NWS/National Hurricane Center) |
Web Site(s) for applicable information:
https://www.ospo.noaa.gov/products/ocean/tropical/
https://www.metoc.navy.mil/jtwc/jtwc.html
Contact Information for Further Information: Please email User Services at spsd.userservices@noaa.gov or Tropical Team Lead Paul Lee at paul.lee@noaa.gov