Koninklijk Nederlands Meteorologisch Instituut; Ministerie van Verkeer en Waterstaat

Mode-S EHS

Mode-S EHS derived meteorological information is available for NMHS, after signing a Non Disclosure Agreement.

Example of the present coverage

Coverage of MUAC Mode-S EHS derived meteorological data. Color scale indicates the lowest level at which an observation was detected.

The data is processed with all necessary corrections:

  • Magnetic to true heading correction
  • Heading corrections
  • Airspeed corrections

The data will be delivered in three formats:

  • BUFR

The data will be delivered every 15 minutes with a delay of 10 minutes.

At present the Mode-S EHS derived meteorological information will be distributed using personal ftp-account. Please contact mode-s@knmi.nl for inquiries on data access.


The BUFR format used at present uses the AMDAR reduction in space and time. At present the new WMO AMDAR format is being implemented.

The new AMDAR version 7 format is implemented. Mode-S EHS meteorological observations can be distiguished from ACARS, etc. by the data subcategory.

Mode-S EHS ascii

The ascii-format is :

Each line one observation

YYYYMMDD HHmmss unique-ID lat(deg) lon(deg) flightlevel(100ft) ff(kt) dd(deg) T(K) phase
20140411 120204 Mc2d506 50.0787 10.9824 253.75 16.205 311.245 235.374 +1

  • phase=0 : level flight
  • phase=+1: ascending
  • phase=-1: descending
Here is a description of the ASCII-format