1.1   Hungarian Meteorological Service

Unit of Aviation Meteorology

The services are provided in accordance with the provisions contained in the following ICAO documents:

• ICAO Annex 3 - Meteorological Service for International Air Navigation;
• ICAO Doc 7030 – Regional Supplementary Procedures;
• ICAO Doc 7754 – Air Naviation Plan / European Region;
• ICAO Doc 8400 – Abbreviation and Codes;
• ICAO Doc 8896 – Manual of Aeronautical Meteorological Practice.

3.1   General Information concerning the execution of Flight Weather Observation in Hungary

Meteorological observations and reports from aeronautical meteorological stations are provided and disseminated according to ICAO Annex 3 regulations.

Flight Weather Observation will be executed depending on personal availabilities as follows:

HUMAN OBS: Local manually:

• Without particular identification label for METAR, SPECI, MET REPORT, SPECIAL
• Quality Control On-Site
• Meteorological data acquisition is done with a semiautomatic operational system which allows manual inputs for all weather parameters
• TREND manually
• Supplementary Information manually as required by the weather situation

AUTO OBS: Automatic WITH TREND:

• With “AUTO” as particular label for METAR, SPECI, MET REPORT, SPECIAL
• Plausibility Check
• Meteorological data acquisition is done with a full automatic operational system which allows limited manual inputs for:
  • TREND manually
  • Supplementary Information manually as required by the weather situation

AUTO OBS: Automatic WITHOUT TREND:

• With “AUTO” as particular label for METAR, SPECI, MET REPORT, SPECIAL
• Meteorological data acquisition is done with a full automatic operational system which does not allow manual inputs and therefore WITHOUT:
  • Quality Control
  • Plausibility Check
  • TREND
  • Supplementary Information

3.2   General Information concerning AUTOMATIC FLIGHT WEATHER OBSERVATION - AUTO OBS

Fundamental differences HUMAN OBS versus AUTO OBS:

• HUMAN OBS processes a total picture of optical, acoustic and visual impressions on site that are representative of the airport and its vicinity and describes the conditions in the surroundings for elements visibility, cloud cover and weather phenomena.
• AUTO OBS processes the point measurements made by sensors in the airport area, which are usually considered to be representative for the area of the airport. AUTO OBS determines exclusively the conditions at the airport by measurement and calculation using algorithms. AUTO OBS can record weather phenomena which are to be reported in accordance with ICAO Annex 3 if they are within the detection range of the sensors.

No differences AUTO OBS opposite HUMAN OBS consist of:

• Wind
• Temperature / Dew Point
• Air pressure (QNH)
• RVR (RVR)

Differences and limitations of AUTO OBS opposite HUMAN OBS can be found at:

• VISIBILITY AND ADDITIONAL VIEW:

  AUTO OBS determines the MET VIS by point measurement with forward-scatter-instruments to the TDZ and MID positions and extrapolating the measured values of up to 20 KM. The required summary values are calculated and reported in accordance with ICAO requirements.

  HUMAN OBS determines the visual reference to visual targets in the area.

  For RVR, there is no difference, as this is determined both HUMAN OBS and AUTO OBS by measuring the forward scattered light measurement systems and calculation.

• CURRENT WEATHER PHENOMENA (PRESENT WEATHER):

  DRSN, BLSN and more, very rare phenomena in Hungary such as SQ, SA, SS, DU, FU, FC cannot be reported by AUTO OBS.
  VC weather phenomena in the environment (Vicinity):
  - VCTS may be reported by AUTO OBS
  - VCSH and VCFG are not recognized

  Clouding phenomena (FG, BR, HZ) are detected in AUTO OBS by the sensor. Algorithms ensure consistency with the sight. Deviations between AUTO and HUMAN OBS can occur (e.g. BCFG, PRFG) if, for example, fog occur beside the sensors.

  FZFG is in the AUTO OBS according ICAO detected by checking with the air temperature, i.e., from T < -0.5 °C FZ is reported.

  Rare manifestations (SA, SS, DU, FU, FC) are not recorded and reported according to visibility as FG, BR or HZ.

  Regarding precipitation some rare phenomena are not specified by the sensors. If detected, these other genera are assigned.

  Comparisons have shown that the following differences between HUMAN OBS and AUTO OBS is to be expected:

  • The precipitation is detected occasionally different, for example, DZ instead of RA, SN instead of SG.
  • Mixed precipitation (RASN) is often reported by the sensor as RA or SN.
  • In the evaluation of the intensity, there are often deviations between light/moderate and moderate/severe categories.
  • There are also differences in the assignment of characterization SH.

  AUTO OBS recognizes thunderstorm TS and VCTS. The data from Weather radar and lightning detection systems are used. The recording quality is good, but there may occasionally be incorrect detections because of wrong positioning of lightnings and unregistered lightning discharges.

  The perception of visual and acoustic observations (thunder and lightning) is given at HUMAN OBS with greater reliability in detecting the near thunderstorms and the redundancy of the system components fail.

  The lack of coverage of SQ in AUTO OBS is mitigated by the availability of current wind data.

• CLOUDS (CLOUD TYPE AND CLOUD COVER):

  Ceilometers are positioned in the areas where the approach path intersects the relevant IFR approaches decision height. The measurement of the lower limit is determined by point measurement (principle laser gun).

  Cloudiness is therefore only recorded in the AUTO OBS, when clouds appear above the sensors.

  Cloud cover (FEW, SCT, …): Calculation using algorithms based on all existing airport environmental sensors. From the period duration of the ceilometer detecting the presence of cloud amount is extrapolated:

  • This works well for homogeneous cloud distribution and rapidly moving clouds.
  • Clouds off the sensors cannot be detected.
  • In stationary situations and orographic clouds significant differences between HUMAN OBS and AUTO OBS may result.

  CB and TCU clouds are detected by weather radar and lightning detection system. The degree of coverage and the height of cloud base, however, cannot be determined automatically. Therefore, it is reported in AUTO OBS as ///.

  SKC is not reported: AUTO OBS reports “NCD = no cloud detected” when no clouds are detected by the sensors.

  CAVOK is reported in AUTO OBS.

  Comparisons have shown that in rare cases groups of clouds are reported FEW001 or FEW002 by false detections of the sensors in the AUTO OBS, although although there are no clouds.

• MONITORING and FAILURE:

  The system for the production and distribution of AUTO METAR is monitored REMOTE by MET and centrally by the technical service of Hungarian Meteorological Service. In case of technical failure of individual sensor, the missing data are replaced by slashes as usual in AUTO reports.

3.3   Meteorological observations at airports

Automated aviation meteorological reports: Automated aviation meteorological observations for Debrecen International Airport (LHDC), Heviz-Balaton Airport (LHSM) and Gyor-Per Airport (LHPR) Aviation in the form of METAR and SPECI are created and disseminated and marked with „AUTO” according to the following conditions:

• All meteorological parameters which are part of human aviation meteorological reports corresponding to ICAO Annex 3, i.e. including TCU, CB, TS, VCTS. Please note that the automated reporting of TCU and CB will not contain TCU/CB amount and TCU/CB height of base.
• TREND (2 hours before operational time and in operational time)
• Supplementary information

Example: METAR LHPR 241115Z AUTO 25003KT 210V290 5000 BR OVC005 15/14 Q1019 BECMG 6000 NSW BKN015=

Automated aviation meteorological observations for Pecs-Pogany Airport (LHPP), in the form of METAR and SPECI are created and disseminated and marked with „AUTO” according to the following conditions:

• All meteorological parameters which are part of human aviation meteorological reports corresponding to ICAO Annex 3, i.e. including TCU, CB, TS, VCTS. Please note that the automated reports of TCU/ CB will not contain TCU/CB amount and TCU/CB height of base.
• NO TREND
• Supplementary Information

Example: METAR LHPP 240545Z AUTO 07002KT 0650 R34/1000D FG FEW003 11/10 Q1019=

The generation of automated aviation meteorological reports is based on measurements at specific locations and algorithms only and not on human observations. A plausibility check of the measured observational data before they are disseminated is done from a remote observing site with the help of video cameras.

3.4   Meteorological Observing Stations at Military Aerodromes

• LHKE Kecskemet
• LHPA Papa
• LHSN Szolnok

Manual Observation Sites are under continuous quality check control by Military Aerodromes.

3.5   Weather radar stations

4.1   Meteorological information for Civil Aviation

The Hungarian Meteorological Service supplies the pilot-in-command with a detailed explanation of the existing synoptic situation and the expected weather conditions during the flight via telephone.

4.2   Meteorological Information for General Aviation

8.1   General

For the safety of air traffic, the Hungarian Meteorological Service - Unit of Aviation Meteorology as Meteorological Watch Office (MWO) maintains an area meteorological watch and warning service. The service consists of the continuous weather watch within the Budapest FIR and if necessary, the issuance of appropriate SIGMET and AIRMET information.

8.2   Area meteorological watch service

The area meteorological watch service is performed by the Hungarian Meteorological Service - Unit of Aviation Meteorology. The MWO issues SIGMET and AIRMET information in accordance with ICAO Annex 3. Chapter 7 and Appendix 6.

SIGMET information is an information issued by a Meteorological Watch Office concerning the occurrence or expected occurrence of specified en-route weather phenomena which may affect the safety of aircraft operations.

SIGMET information for the Budapest FIR is disseminated internationally as well as nationally and will be broadcast by Budapest VOLMET.

SIGMET refer to the following phenomena:

• OBSC, EMBD, FRQ, SQL thunderstorms with or without hail
• severe turbulence
• severe icing
• severe icing due to freezing rain
• severe mountain waves
• volcanic ash cloud
• heavy duststorm
• heavy sandstorm
• radioactive cloud

SIGMETs concerning tropical cyclones are not issued by MWO due to meteorological reasons.

SIGMETs are numbered sequentially from 0001 UTC.

AIRMET information gives a concise description in abbreviated plain language, concerning the occurrence or expected occurrence of specified en-route weather phenomena.

AIRMET information is provided by MWO Budapest and refers to the portion of Budapest FIR from the ground up to FL100

AIRMET is used as amendment of GAMET.

AIRMET information refers to the following phenomena:

• widespread mean surface wind speed above 30 KT
• widespread area of visibility less than 5000 M
• widespread area of BKN or OVC CLD with cloud base below 1000 FT AGL
• ISOL, OCNL thunderstorms with or without hail
• ISOL TCU, OCNL TCU, FRQ TCU, ISOL CB, OCNL CB, FRQ CB
• moderate icing
• moderate turbulence

AIRMETs are numbered sequentially from 0001 UTC.

AIRMET messages relevant to the Budapest TMA will be included in the ATIS broadcast for Budapest Liszt Ferenc International Airport.

Transmission of SIGMET and AIRMET information will only be made by the ATC units of Budapest ATS centre in the case of equipment failure or when requested by the pilot.

The flight information sectors of the Budapest ATS centre will communicate SIGMET and AIRMET for Budapest FIR without pilot request to aircraft operating on flight plan and maintaining radio communication.

SPECI and TAF AMD for foreign aerodromes are provided by the ATS units on pilot request only.

The flight information sectors of the Budapest ATS centre will communicate SPECI and TAF AMD for individual domestic aerodromes to aircraft without the need for the pilot to request such information.