Washington VAAC

What you can build

• Hold air freight through an ash-affected corridor

  When a new advisory's forecast polygon crosses a lane you ship through, the operator proposes holding the affected orders and tells you which advisory number and volcano triggered it.

  With Weather Hold

• Reset promise dates for delayed air lanes

  The operator reads the T+6, T+12, and T+18 hour forecasts for volcanoes near your hub airports and proposes new promise dates for orders routed through them.

  With Promise Date

• Attach the advisory to a carrier exception

  When a carrier reports a delay at an airport inside a current advisory, the operator attaches the advisory text to the exception and proposes the customer message.

  With Carrier Exception

• Warn staff about flight disruption

  For sites within the advisory's area, the operator drafts a notice that quotes the observed ash cloud and the next advisory time, for you to approve before it goes out.

  With Severe Weather Notice

Requirements

• The volcano names or Smithsonian numbers near your routes, airports, or sites, as written on the advisory VOLCANO line
• A parser for the text advisory or the IWXXM XML; flight levels are given as FL values and positions in degrees and minutes
• A client that re-reads the messages page or the XML files on a schedule, since the pages document no push feed
• Geometry for your airports and lanes to test against the observed and forecast polygons

Authentication

None. Advisories, XML, KML, and graphics are open on ospo.noaa.gov without a key or account.

Limits

• No API, RSS, or webhook is documented on the OSPO pages; advisories are read from HTML, XML, KML, and JPEG files
• Advisories are written for aviation and describe airborne ash by flight level; the format has no field for ash fall on the ground
• A user notice now says VAAC Montreal and VAAC Darwin cover the northern and southern portions of the Washington area until further notice
• The OSPO pages state no data licence; NESDIS says it supports the full and open exchange of environmental satellite data and products

Questions and answers

How often are advisories issued?

The OSPO page says Volcanic Ash Advisories are issued every 6 hours or sooner for ash-active volcanoes, with a Volcanic Ash Graphic when ash is detected. Each advisory ends with a NXT ADVISORY line naming the time by which the next one will be issued.

What is in an advisory?

A WMO header such as FVXX20 KNES, the issue DTG, the volcano name and number, position, area, summit elevation, advisory number, information sources, eruption details, the observed ash cloud with flight levels and movement, forecasts at +6, +12, and +18 hours, remarks, and the next advisory time.

Is there a machine-readable form?

Yes. Each advisory is published as an IWXXM 3.0 VolcanicAshAdvisory inside a WMO MeteorologicalBulletin XML file, and as a KML file of observed and forecast polygons. The messages page links both beside the text advisory.