HYSPLIT model volcanic ash cloud forecast guidance for current eruptions in the Washington and Anchorage VAAC areas of responsibility.NOTE: On January 25, 2005, NOAA NCEP began running HYSPLIT instead of VAFTAD for volcanic ash dispersion modeling. HYSPLIT model output forecast guidance charts with headers PHBE10 KWBC and PHBI10 KWBC are issued by the NWS over WAFS. They are made available, subject to the disclaimer on the respective web pages, by the NWS OOS and AWC, by the Washington VAAC, and by the Air Resources Laboratory in the table here. The HYSPLIT charts are NOT official forecasts; they are guidance only. SIGMETs contain the official forecast. Some domestic and U.S. Offshore SIGMETS are issued from the AWC. No volcanic ash dispersion model forecasts (products kept online 2 days)
Other official volcanic ash products are Volcanic Ash Advisories, issued from Volcanic Ash Advisory Centers (e.g. Washington and Anchorage). See the appropriate Volcanic Ash Advisory Center (VAAC) for information on volcanic eruptions in other parts of the world.
The HYSPLIT model output charts in VAFTAD-format consist of a series of maps showing the forecast ash cloud in time and space. The 4 panels in any column are for a single valid time after eruption. Individual panels are for layers applicable to aviation operations and are identified at the side of a panel with upper and lower flight levels (FL) in hundreds of ft. The bottom panel is a composite from the SURFACE to FL550. For each column, the forecast valid time separates the upper three panels from the composite panel. Volcano eruption information is at the lower left. A description of the input meteorology is at the lower right with a message to "SEE CURRENT SIGMET FOR WARNING AREA". The visual ash cloud symbol and run description are at the lower center.
Further information: Related links
Inquiries should be addressed to: |
barbara.stunder@noaa.gov
