GEN 3.5  Meteorological services

3.5.1  KINGDOM OF BAHRAIN

3.5.1.1  Responsible Service

The Meteorological Services for civil aviation at Bahrain are provided by the Bahrain Meteorological Service.

Post:

Bahrain Meteorological Service
Civil Aviation Affairs
Bahrain International Airport
P.O. Box 586
Kingdom of Bahrain

Tel:+973 17321178 (MET Briefing), +973 17323073 (Forecaster)

Fax:+973 17320630

AFS:OBBIYMYX

The service is provided with the provisions contained in the following ICAO documents:

  • Annex 3: Meteorological Service for International Air Navigation

  • Annex 15: Aeronautical Information Service

  • Doc 8126: Aeronautical Information Services Manual

  • Doc 7030: Regional Supplementary Procedures

  • Doc 8700: Air Navigation Plan, MID / ASIA

  • Doc 9377: Co - ordination between ATS and the Meteorological Services

Differences from these provisions are detailed in Section GEN 1.7.

3.5.1.2  Area of Responsibility

Meteorological Watch Office for the BAHRAIN FIR / BAHRAIN UIR.

Air routes from Bahrain to:North America
Europe
South Africa
The Far East
3.5.1.3  Observing Systems and Operation Procedures
3.5.1.3.1 Surface wind is measured by ultrasonic wind sensor located approximately 350 M WSW of THR RWY 30L and at RWY 12R. Wind indicators are located in the meteorological units of Briefing, Observing and Operations and in the appropriate Air Traffic Services Units.

Cloud height is estimated. However Vaisala Ceilometer cloud measurements are also available near the RWY 30L.

Temperature and huminidity readings are taken from instruments located at a site some 250 M from the RWY, near to the THR RWY 30L.

Vertical / horizontal wind - shear warnings are issued.

Slant visual range observations are not made.

Visibility is estimated except for IRVR as follows.

3.5.1.3.2 IRVR REPORTING PROCEDURES
3.5.1.3.2.1 IRVR reporting is initiated when:

  1. The regular meteorological report shows visibility to be 2000 M or less;

  2. The IRVR value is observed to be 2000 M or less;

  3. Whenever shallow fog is reported, and during periods for which it is forecast.

Note: In METAR, only the touchdown and stop end values are given.

3.5.1.3.2.2 IRVR values will be passed to all aircraft at the beginning of each approach for landing and thereafter, any significant change to the IRVR is passed until the aircraft has landed. A significant change is defined as a change in value of one increment or more. IRVR information will also be provided to aircraft prior to take off.
3.5.1.3.2.3 The IRVR is measured by forward scattering visibility sensor and the system consists of three transmission meters indicating Touch - down, Mid point and Stop - end values for the RWY in use. Where all three readings are reported to the pilot, they are passed as three sets of figures representing Touch - down, Mid point and Stop - end respectively. e.g.:

RVR 650 - 500 - 550

3.5.1.3.2.4 If only two values are passed they will be identified, for example, as follows:

RVR Touch - down 650 - Stop - end - 550

3.5.1.3.2.5 If only one unit is serviceable it will be identified, for example, as follows:

RVR Mid - point 650

except that if the only serviceable unit is the Stop - end, the value will not be reported and the whole system will be placed unserviceable for that RWY.

3.5.1.4  Meteorological Observations and Reports

Table GEN 3.5.1.4 Meteorological Observations and Reports

Name of Station Location Indicator

Type and frequency of observations / autom. equipment

Types of MET reports and Suppl. Information included

Observation System and sites

Hours

Climatological Information Available

BAHRAIN MET

BAHRAIN INTERNATIONAL

OBBI

Half hour plus special observations

METAR, SPECI, TREND & WS

SFC wind sensors RVR EQPT Ceilometer Thermometer See AD Chart

H24

Climatological tables AVBL

3.5.1.4.1  NOTIFICATION REQUIRED FROM OPERATORS

Pursuant to ICAO Annex 3, chapter 2, paragraph 2.3, notification in respect of all flight documentation and briefing is normally required. Such notification should normally be received at least six hours before expected departure time for flight of more than 1500 NM and at least 2 hours before expected departure time for flights of 1500 NM or less.

3.5.1.5  Types of Service

A 24-hour personal briefing and consultation service for flight crews is provided. Flights documentation provided comprises prognostic charts of upper air (for 250 MB) and significant weather (above FL 250) for long - haul flights. Charts for 500, 300 and 200 MB are available by prior arrangement. Rout sector winds for 700 MB and significant weather charts (above 10000 FT) are provided for regional flights.

Take-off data and climb and descent winds are also provided, together with the latest available aerodrome forecasts for designation and alternates.

Satellite imagery and local weather radar displays are available for inspection at the MWO and satellite imagery can be provided on request.

3.5.1.6  Aircraft Reports required from Pilots

In Flight

In accordance with Annex 3, chapter 5, paragraph 5.3.1, the marking and transmission of aircraft reports (AIREP) is required of the following ATS reporting points:

BAHRAIN (DAVRI, TORBO, SODAK or SOGAT)

Reports also requested at:

TOMSO, DEGSO, RESAR, ORSIS, TUMAK, ALPOB, ORMID, ULADA, RABAP

After landing

To establish a data-base for validating enhanced forecast information for take-off procedures, pilots of aircraft equipped with Flight Management Systems are requested to record winds and temperatures at and below 3000 FT at 500 FT intervals on a pro forma provided, and submit it to ground services after landing whenever operational requirements permit.

Pro forma are available from BAHRAIN AIRPORT SERVICES (BAS) and the MET / AIS Briefing Office.

3.5.1.7  VOLMET Service

Name of Station

Call Sign ID (EM)

Freq.

BCST period

Hours of services

ADs included

Continents & Format of REP and FCST & Remarks

BAHRAIN

BAHRAIN VOLMET

(A3E)

128.800 MHZH24CNS

OBBI, OEDF, OEJN, OERK, OKBK, OMAA, OMDB, OMRK, OMSJ, OMMS, and OTBD

METAR, TREND, QNH
3.5.1.8  SIGMET Service / Validity

Name of MWO / Location Indicator

Hours

FIR Served

Type of SIGMET / Validity

Specific Procedures

ATS Unit served

Additional Information

BAHRAIN

H24

BAHRAIN FIR / BAHRAIN UIR

SIGMET / 4 HR SIGMET SST / 4 HR

NIL

BAHRAIN ACC

SHAIKH ISA APC

DOHA APC

NIL

3.5.1.8.1  General

For safety of air traffic the Bahrain Meteorological Service maintains an area meteorological watch and warning service. This service consists partly in a continuous weather watch within the FIR / UIR and the issuance of appropriate information (SIGMET) by the Meteorological Watch Office, partly in the issue of warnings for BAHRAIN INTERNATIONAL airport and, subject to agreement, for other aerodromes by all aeronautical MET office.

3.5.1.8.2  Area Meteorological Watch Service

The area meteorological watch service is performed by the Bahrain Meteorological Watch Office. The MWO issues information in the form of SIGMET messages about occurrence or expected occurrence of one of several of the following significant meteorological phenomena.

  • Thunderstorms* (Obscured, Embedded, Frequent, Obscured with Hail, Embedded with Hail, Frequent with Hail).

  • Severe turbulence

  • Severe icing

  • Severe mountain waves

  • Heavy sands / dust - storm

  • Volcanic ash cloud

  • Tropical cyclone

* Area of widespread Cumulonimbus clouds or Cumulonimbus along a line (squall line) with little or no space between individual clouds, or Cumulonimbus embedded in cloud layers or obscured by haze.

SIGMET SST messages are issued as required and relate to the following phenomena:

  • Cumulonimbus

  • Turbulence (mod / severe/)

  • Hail

  • Volcanic ash cloud

The SIGMETS are issued in abbreviated plain language using ICAO abbreviations and are numbered consecutively for each day commencing at 0001. Their period of validity is generally limited to 4 hours or less from the time of transmission. The MWO transmits SIGMETS issued by itself as well as SIGMETS of adjacent. MWOs. SIGMET Information is disseminated.

  1. by the Area Control Centre Bahrain for the BAHRAIN FIR / BAHRAIN UIR;

  2. by ATS units for their own area of responsibility.

The information is broadcast from Aeronautical Communication Centre and repeated every half and full hour during the period of validity of the SIGMET Information.

3.5.1.8.3  Warning Service

Warnings are issued for the safety of aircraft taking off and landing for the protection of parked and moored aircraft or equipment at the airport. Warnings are issued in plain language.

Aerodrome Warnings are issued when one or more of the following phenomena are expected to affect the airport:

  • Thunderstorm

  • Squall 1

  • Sandstorm / dust storm

  • Rising sand / dust

  • Strong surface wind 2

  • Temperature inversion 3

  • Hail

  • Low level turbulence

Note 1: squall relates to a sudden increase of wind speed of at least 16 KT, the speed being 22 KT or more.

Note 2: strong wind refers to mean wind speed of 22 KT or more and / or gusts of 28 KT or more.

Note 3: Temperature inversion warnings are issued for a lapse of 07° C or more, at or below 1500 FT.

Wind Shear Warnings are issued within a radius of 8 KM from the airport and up to 1600 FT. For vertical Shear the following criteria are used:

  • Mod 5 - 8 KT / 100 FT

  • Str 9 - 12 KT / 100 FT

  • Svr 12 or more KT / 100 FT

Horizontal shear refers to a vector change of more than 20 KT. All warnings are valid for 1 to 4 hours unless cancelled. Each type of warnings is numbered consecutively on a monthly basis.

The warnings are issued in English and are distributed in accordance with a distribution list which has been agreed upon locally. In order to guarantee a rapid dissemination of the warnings, the distribution list used contains only one recipient for an interested group; this recipient will be responsible for the further dissemination for the warnings within the group.

3.5.1.9  Other Automated Meteorological Services

NIL

3.5.1.10  Meteorological Briefing at Aerodromes

Details of meteorological briefing at aerodromes are given in the individual aerodrome subsections i.e. AD 2.