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Responsibilities and timeliness for aircraft reconnaissance and surveillance data (Text)

Misunderstandings exist about how NOAA's National Hurricane Center (NHC) obtains aircraft reconnaissance and surveillance data and how those data are disseminated. Some have concluded incorrectly that NOAA's National Weather Service (NWS) delays release of some data. We expect the information below to clarify these issues.

1. All NOAA G-IV and P-3 aircraft data except "Vortex Messages" are transmitted from the aircraft automatically and immediately through National Weather Service (NWS) dissemination systems to reach users.
2. Remaining aircraft data (including "Vortex Messages" from the U.S. Air Force C-130s and NOAA P-3s) go through a quality control (QC) process by the aircrew and by the U.S. Air Force unit--the Chief, Aerial Reconnaissance Coordination All Hurricanes (CARCAH)-- collocated with the NHC. CARCAH, not the NWS/NHC, disseminates these products after the QC process is complete.
3. Preliminary reconnaissance data are often shared by CARCAH with the collocated operational hurricane forecaster before CARCAH completes the QC process. NHC products and/or media interviews sometimes reflect this preliminary data up to a few minutes before the QC process is complete and CARCAH generates and disseminates its Vortex Message product.
4. The time stamp on the CARCAH Vortex Message product from the C-130s is actually the time the crew on those aircraft locate the center of the tropical cyclone. It can take up to 20 minutes for the crew to complete their data analysis process and for the information to make its way to CARCAH and the NHC facility from the aircraft. More time is required for data QC, product generation, and dissemination. This is the reason customers may receive the product 30 minutes, give or take, after the vortex message time stamp, and this could be a source of the misunderstanding.

In short, there is no intentional delay in releasing hurricane reconnaissance data by NOAA or by the Air Force.

Note: Once the Air Force Reserves switch from using the older C-130H models to flying the newer C-130J models, a software change is expected to enable CARCAH to time stamp the product with the actual time the Vortex Message is generated, rather than a time that precedes completion of the data gathering, analysis, QC, and product generation process.