Current HYSPLIT Volcanic Ash Forecast Guidance

NOTE: this web server is not maintained in an "operational" environment and should not be relied upon for 24/7 access.

NOTE: please read below for official sources of forecasts.

HYSPLIT model volcanic ash cloud forecast guidance for current eruptions in the Washington and Anchorage VAAC areas of responsibility.

HYSPLIT model output forecast guidance charts with headers PHBE10 KWBC and PHBI10 KWBC are issued by the National Weather Service (NWS) over WAFS and are made available, subject to the disclaimer on the respective web pages, by the NWS TOC and AWC. They are also made available, subject to the disclaimer on the respective web pages, by the NOAA Washington VAAC, and by the NOAA ARL (this web page) in the table below.

The HYSPLIT charts are NOT official forecasts; they are guidance only.

SIGMETs contain the official forecast: continental U.S., Alaska, Alaska-alternate, Hawaii, off-shore

Other official products are Volcanic Ash Advisories

VOLCANO	model forecast hours
POPOCATEPETL	+12 & +24	+36 & +48
TUNGURAHUA	+12 & +24	+36 & +48

Timely delivery of data and products from this server over the Internet is not guaranteed (see the disclaimer). Due to unforeseen circumstances, HYSPLIT charts may not be on this web site even though they have been issued by the NWS. Do not rely on obtaining volcanic ash HYSPLIT products from this web site.

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:

Heffter, J.L. and B.J.B. Stunder, 1993: Volcanic Ash Forecast Transport And Dispersion (VAFTAD) Model. Wea Forecasting, 8 534-541.

Inquiries should be addressed to:
Barbara Stunder
Email: barbara.stunder@noaa.gov