METEOROLOGICAL SERVICESRESPONSIBLE SERVICELithuanian Hydrometeorological Service under the Ministry of Environment is a meteorological service provider for civil aviation and is responsible for:provision of aerodrome forecasts and warnings;provision of , , special air-reports, area forecasts;provision of meteorological information to and search and rescue units;provision of consultations to flight crew members and other flight operations personnel;provision and distribution of pre-flight meteorological information and flight documents;weather observing and reporting service at Vilnius, Kaunas, Palanga aerodromes;provision of aerodrome climatological information.LITHUANIAN HYDROMETEOROLOGICAL SERVICE UNDER THE MINISTRY OF ENVIRONMENT (LHMS) HEADQUARTERSOršos Str. 8LT-09300 VILNIUS, LITHUANIATel.:+370 648 06 572Email:lhmt@meteo.ltURL:www.meteo.ltLHMS FORECASTS AND WARNINGS DIVISION (AVIATION) FORECASTER:Oršos Str. 8LT-09300 VILNIUS, LITHUANIATel.:+370 648 05 448, +370 648 06 768Fax:+370 5 272 69 12Email:amc_vilnius@meteo.ltLHMS METEOROLOGICAL AND AVIATION WEATHER OBSERVATIONS DIVISION OBSERVER AT VILNIUS AERODROMERodūnios kl. 2 LT-02188 VILNIUS, LITHUANIATel.:+370 648 06 239 AFS:EYVIYMYX Email:amc_stebetojai@meteo.lt LHMS METEOROLOGICAL AND AVIATION WEATHER OBSERVATIONS DIVISION OBSERVER AT KAUNAS AERODROMEOro uosto Str. 4 LT-54460 KARMĖLAVA, LITHUANIATel.:+370 648 05 452 AFS:EYKAYMYX Email:ams_kaunas@meteo.lt LHMS METEOROLOGICAL AND AVIATION WEATHER OBSERVATIONS DIVISION OBSERVER AT PALANGA AERODROMELiepojos pl. 1 LT-00169 PALANGA, LITHUANIATel.:+370 648 05 467 AFS:EYPAYMYX Email:ams_palanga@meteo.lt Lithuanian Air Force Air Base Air Operations Group Air Operations Support Squadron Meteorological Section provides the meteorological service for air navigation at Šiauliai aerodrome:Lakūnų Str. 3LT-77103 ŠIAULIAI, LITHUANIATel.:+370 648 05 467 Fax:+370 41 59 21 92URL:www.kariuomene.ltMETEOROLOGISTTel+370 45 50 70 10Fax:+370 5 211 38 98AFS:EYSAYMYX Email:abmeteo@mil.ltLithuanian Air Force Air Base Air Operations Group Air Operations Support Squadron Meteorological Section is responsible at Šiauliai aerodrome for:weather observing and reporting service;pre-flight meteorological information distribution;meteorological information distribution to units.Oro navigacija AB is responsible for the provision of Automatic Terminal Information Service (ATIS):ORO NAVIGACIJA ABAIR TRAFFIC CONTROL SYSTEM MAINTENANCE DIVISIONBalio Karvelio Str. 25LT-02184 VILNIUS, LITHUANIATel.:+370 706 94 502Email:info@ans.ltURL:www.ans.ltThe meteorological services are provided in accordance with the requirements of the following and European Union documents:ICAO Annex 3–Meteorological Service for International Air NavigationICAO Doc 7030–EUR Regional Supplementary ProceduresICAO Doc 7754–EUR Air Navigation PlanCommission Implementing Regulation (EU) 2017/373Differences from ICAO Annex 3 standards and recommended practices are listed in GEN 1.7 part.AREA OF RESPONSIBILITYMeteorological services are provided within the Vilnius Flight Information Region (FIR). LHMS Forecasts and Warnings Division acts as Meteorological Watch Office (MWO) and Aerodrome Meteorological Office (AMO), LHMS Meteorological and Aviation Weather Observations Division and Lithuanian Air Force Air Base Air Operations Group Air Operations Support Squadron Meteorological Section as Aeronautical Meteorological Stations within the Vilnius FIR.LHMS Forecasts and Warnings Division (aviation) is also responsible for the provision of meteorological services in the NINTA-ADAXA route. METEOROLOGICAL OBSERVATIONS AND REPORTSName of station ICAO Location IndicatorType & frequency of observation/ autom. Types of reports & availability of forecastsObservation System & Site(s)Hours of operationClimatological information123456KAUNASEYKAHalf hourly routine, Special obs, , METAR AUTO, MET REPORT, SPECIAL, MET REPORT AUTO, AUTO wind sensors: two ultrasonic sensors (height 10 M) 325 M from 08, 120 M north from the RWY CL, 266 M from DTHR RWY 26, 138 M north from the RWY CL./ :three transmissometers are 330 M from DTHR RWY 08, 105 M south from the RWY CL, 405 M from DTHR RWY 26,105 M south from the RWY CL and at mid-point of RWY 08/26 95 M south from RWY CL.Ceilometers:two laser ceilometers 820 M west from DTHR RWY 08 and 1044 M east from DTHR RWY 26.Pressure, air temperature, air humidity sensors:one pressure sensor is on the mast of wind sensor located at 325 M from DTHR RWY 08. Two temperature and air humidity sensors are on the masts of wind sensors 325 M from DTHR RWY 08 and 266 M from DTHR RWY 26. Digital barometer is in the AWOS room. Lightning sensor: 354 M from DTHR RWY 08 and 120 M north from RWY CL.Wind shear EQPT: NILH24Climatological tables PALANGAINTLEYPAHalf hourly routine, Special obs, AWOSMETAR, METAR AUTO, MET REPORT, SPECIAL, MET REPORT AUTO, SPECIAL AUTO wind sensors: two ultrasonic sensors (height 10 M): 275 M from DTHR RWY 01, 118 M west of the RWY CL and 292 M from DTHR RWY 19,138 M west of the RWY CL./ :two transmissometers are 314 M from DTHR RWY 01, 112 M west of the RWY CL and 298 M from DTHR RWY 19, 112 M west of the RWY CL.Ceilometers:two laser ceilometers are 880 M to the south from DTHR RWY 01 and 835 M to the north from DTHR RWY 19.Pressure, air temperature, air humidity sensors:one pressure sensor is on the mast of wind sensor located at 292 M from DTHR RWY 19. Two temperature and air humidity sensors are on the masts of wind sensors 275 M from DTHR RWY 01 and 292 M from DTHR RWY 19. Digital barometer is in the AWOS room.Lightning sensor: 930 M from DTHR RWY 01 and 130 M west from RWY CL.Wind shear EQPT: NILH24Climatological tables AVBLŠIAULIAIINTL//EYSAHalf hourly routine, Special obs, MIDAS IVMETAR, METAR AUTO, MET REPORT, SPECIAL, MET REPORT AUTO, TREND wind sensors: two ultrasonic sensors 374/338 M from RWY 14L/32R. / :transmissometers are 390/347 M from THR RWY 14L/32R and at mid-point of RWY 14L/32R.Ceilometers:1045/655 M from THR RWY 14L/32R.Pressure, air temperature, air humidity sensors:two sensors 374/338 M from THR RWY 14L/32R. Digital barometer on TWR in MET aids MIDAS IV Office.Wind shear EQPT: NILH24Climatological tables AVBLVILNIUSINTLEYVIHalf hourly routine, Special obs, AWOSMETAR, MET REPORT, SPECIAL, TREND wind sensors: two ultrasonic sensors (height 10 M) 450 M from THR RWY 01, 105 M east from RWY CL, 395 M from THR RWY 19, 120 M east from RWY CL./ :three transmissometers are 365 M from THR RWY 01 and 95 M east from RWY CL, 365 M from THR RWY 19 and 95 M east from RWY CL, at mid-point of RWY 01/19 95 M east from RWY CL.Ceilometers:two laser ceilometers 888 M south from THR RWY 01 and 1023 M north from THR RWY 19.Pressure, air temperature, air humidity sensors:one pressure sensor is on the mast of wind sensor located 450 M from THR RWY 01, two air temperature and air humidity sensors are on the masts of wind sensors 450 M from THR RWY 01 and 395 M from THR RWY 19. Digital barometer is in the AWOS room.Lightning sensor: One sensor 530 M from THR RWY 19 and 135 M east from RWY CL.Wind shear EQPT: NILH24Climatological tables AVBLReports of surface weather observationsReports of surface weather observations consist of:Routine reportsEYVI – half-hourly report (H+20 and H+50) in METAR and local routine report (MET REPORT) forms;EYKA, EYPA and EYSA – half-hourly report (H+20 and H+50) in METAR, MET REPORT, METAR AUTO and MET REPORT AUTO form.Special reportsSpecial observations - local special report (SPECIAL) - are made between the routine observations whenever significant deteriorations or improvements of weather conditions in accordance with Commission implementing regulation (EU) 2017/373 change to/or pass through the established values. Additionally special criteria for the change of and RWY in use are used. Reports of special observations are issued as SPECIAL for dissemination at the aerodrome of origin.METAR, METAR AUTO are disseminated beyond the aerodrome of origin via AFTN channel. METAR for EYVI is included in Riga broadcast.Local reports are displayed at ATS units displays and meteorological information from local reports is disseminated via ATIS broadcasts. Automatic reports are made without human intervention.TREND forecast is appended into METAR, MET REPORT and SPECIAL reports for EYVI and EYSA.METAR AUTO and MET REPORT AUTO provided without TREND forecast for EYSA.Observing Systems and Operating ProceduresAt all aerodromes automated weather observing systems (AWOS) are installed. Human meteorological observations (visibility, cloud type and/or amount, some of present weather phenomenon and supplementary information) are made additionally to automated observations. Appropriate ATS units, briefing at EYVI and aerodrome offices have a real time weather displays with all data measured by AWOS including data inserted manually by human observers. At EYVI, EYKA and EYPA all displayed data are updated in 10 s intervals. At EYSA displayed data values on the monitors are updated when particular data values are measured by AWOS. Surface wind. Surface wind speed and direction are measured by ultrasonic sensors located at both ends of the runway near THR at a height of 10 M above the ground surface.The unit knot (KT) is used to indicate surface wind speed. 10 minutes average of the true wind direction and wind speed, variation in wind direction (consisting of the two extreme directions between which the wind has varied during the past 10 minutes) and variation from the mean wind speed (gust) during the past 10 minutes are reported in METAR. The wind data from the wind sensor representing of the current RWY in use is always included in a current reports. The magnetic wind direction and speed (2-minute average), variation in wind direction and variations from the mean wind speed (gusts) (during the past 10-minutes) are reported in local reports and transmitted to ATIS for broadcasts. On ATS unit’s real time weather displays all wind data, including crosswind and headwind/tailwind values, relating to the wind sensors installed near the runway, are displayed. Visibility. Visibility is measured by transmissometers at a height of approximately 2.5 M above RWY or observed visually by human observer (if necessary) and reported in metres. At all aerodromes reported visibility in METAR is a prevailing visibility (10-minute average median value) determined from all measuring sites. When the visibility is not the same in different directions and the lowest visibility is different from the prevailing visibility and less than 1500 M orless than 50% of the prevailing visibility and less than 5000 M, the lowest visibility is also included in METAR (with or without indication of its general direction).At EYKA and EYPA automatic METAR reports a visibility value (10-minute average) from the measuring site representative to TDZ of the current RWY in use is included.At EYVI, EYKA and EYPA in local reports a visibility value (1-minute average) from the measuring site representative to TDZ of the current RWY in use is included. At EYSA in local reports a visibility values (1-minute average) from all measuring sites are included.At all aerodromes on ATS unit’s real time weather displays visibility data (1-minute average) from all measuring sites representing all zones along the runway are displayed.Runway Visual Range. Assessment of the runway visual range (RVR) is carried out by means of transmissometers. The RVR assessments are performed using MOR values from transmissometers and information of background luminance and runway light intensity. The RVR is reported in meters throughout periods when the visibility or the RVR is less than 1 500 M. The lower limit for RVR reporting is 50 M and 2 000 M is the upper limit. The RV reported in METAR is RVR (10 minute average) assessed using MOR from measuring site representative to TDZ of the current RWY in use and using 100% runway light intensity. The RVR reported in local reports at EYVI, EYKA, EYPA and EYSA is RVR (1 minute average) values assessed using MOR from all measuring sites representing all zones along the runway and using runway light intensity:for a runway with the lights switched on, the light intensity actually in use on that runway; and for a runway with lights switched off (or at the lowest setting pending the resumption of operations), the optimum light intensity that would be appropriate for operational use in the prevailing conditions. On ATS unit’s real time weather displays RVR data (1-minute average) from all measuring sites representing all zones along the runway are displayed.Present weather. The present weather phenomena are observed by means of a present weather sensors, integrated into transmissometers, lightning detector and additionally by the observer. Clouds. Laser ceilometers are used at all aerodromes to determine the height of cloud base and cloud amount or vertical visibility in case when the sky is obscured and cloud base is not detected. They are installed at ILS MM at the both ends of the RWY. The height of cloud base or vertical visibility is reported in feet above the aerodrome elevation. The height of cloud base is reported in steps of 100 FT up to 10 000 FT and the vertical visibility is reported in steps of 100 FT up to 2 000 FT. The ICAO recommended algorithm is used for cloud base and amount calculations.In local routine and local special reports at EYVI, EYKA and EYPA to report the height of cloud base steps of 50 FT up to and including 300 FT and steps of 100 FT between 300 FT and 10 000 FT are applicable, and the vertical visibility - steps of 50 FT up to and including 300 FT and steps of 100 FT between 300 FT and 2 000 FT. In local reports at EYSA to report the height of cloud base steps of 100 FT up to 10 000 FT are applicable, and the vertical visibility – steps of 100 FT up to 2 000 FT. Only cloud of operational significance (a cloud with the height of cloud base below 5 000 FT or a cumulonimbus cloud or a towering cumulus cloud at any height) is included in local reports. Type of cloud, if applicable, is inserted to reports (except fully automatic reports) by a human observer. In automatic reports at EYKA and EYPA type of clouds is indicated as not available by the use of code ///. In automatic reports at EYSA type of clouds is not indicated as not available.On ATS unit’s real time weather displays the data on the height of cloud base, amount and type of clouds are displayed. At EYVI ATS weather displays instant measured data (in 30 s intervals) on cloud height is displayed additionally.Air temperature and dew point temperature. Air temperature and air humidity (from which the dew point temperature is calculated) at EYKA are measured by sensors placed 2 M above the ground on mast of the wind sensor RWY08, at EYVI, EYPA, EYSA – on the masts of wind sensors at the both ends of the RWY. All measured values are updated in 60-second intervals. On ATS unit’s real time weather displays the data on the air and dew point temperature are displayed (Celsius degrees).Atmospheric pressure. Digital aviation barometers are used as main and backup sensors for QNH and QFE values calculations. All values are updated in 60-second intervals. The QNH value in steps of whole hectopascal is included in all reports. On ATS unit’s real time weather displays QNH and QFE values in are displayed. At EYVI, EYKA and EYPA ATS weather displays QNH and QFE values in Hg and mmHg units are displayed additionally. At EYSA ATS weather displays QNH and QFE values in mmHg units are displayed additionally.Supplementary information. In METAR and SPECIAL reports information on wind shear, based on aircraft reports. In local reports (except automatic reports) information on wind shear along the take-off path or approach path and other supplementary information received from aircrafts via ATS units (including severe and moderate turbulence or icing) is included by a human observer. RWY surface temperature, water film height and freezing points are measured by the road sensors at EYSA at both ends of the RWY. TYPES OF SERVICESForecasting servicesForecasting services for aerodromes in Lithuania are provided by the LHMS Forecasts and Warnings Division (aviation), which carries out the duties of AMO. Aerodrome forecasts Aerodrome forecasts are prepared in code form. 24-hour validity period TAFs (0024, 0606, 1212, 1818) are issued every 6 hours for EYVI, EYKA and EYPA, 9-hour validity TAFs (0009, 0312, 0615, 0918, 1221, 1524, 1803) are prepared every 3 hours for EYSA. TAFs are disseminated no earlier than 1 hour before the commencement of their validity. If necessary, TAF amendments (/) are issued. TAFs are disseminated to OPMET banks and SADIS. Forecasts for landingForecasts for landing for EYVI are provided by LHMS Forecasts and Warning Division (aviation), for EYSA – Lithuanian Air Force Air Base Air Operations Group Air Operations Support Squadron Meteorological Section. Forecasts for landing are prepared in TREND code form. A TREND forecast contains a concise statement of the expected significant changes in the meteorological conditions (surface wind direction and speed and their variations, visibility, phenomena, and clouds) at that aerodrome and is appended to METAR/SPECIAL. The period of validity of a TREND is 2 hours from the time of the METAR/SPECIAL, which forms part of the landing forecast.Forecasts for take-offForecasts for take-off from EYVI, EYKA, EYPA and EYSA are prepared on request and contain concise information about expected meteorological conditions (surface wind direction and speed and their variations, air temperature, and atmospheric pressure) over RWY. The period of validity of the forecast for take-off is 2 hours. Forecasts for take-off from EYVI, EYKA, EYPA and EYSA can be obtained by contacting LHMS Forecasts and Warnings Division (aviation) by phone +370 648 05 448 or +370 648 06 768 at least 3 hours before the expected departure of the aircraft.Atmospheric pressure forecastsQNH forecasts contain concise information about expected minimal QNH values within each area of the Vilnius FIR. The distribution of areas is shown in Figure 1. QNH forecasts are issued every 6 hours for validity periods 0309, 0915, and1521 UTC and transmitted to ATS units not later than 1 hour before the commencement of their validity. QNH forecasts are continuously monitored, and amendments (AMD) are issued if necessary. Area forecasts for low-level flights Area forecasts for low-level flights are prepared as a significant weather prognostic chart below FL100. The SIGWX chart contains information on meteorological information that may have an impact on low-level flights within Vilnius FIR and further into Europe. SIGWX chart is issued every 6 hours during daylight time at fixed forecast times of 0600, 1200, and 1800 UTC not later than 1 hour before the commencement of their validity. The SIGWX chart covers a 6-hour period of validity (3 hours before and 3 hours after the fixed time). The graphical part of a SIGWX chart depicts the weather situation at the beginning of the validity period. The SIGWX chart shows the position, direction, and speed of movement of atmospheric pressure centers and surface fronts, the boundaries of significant weather zones, and depicts information about:the following phenomena warranting the issuance of a , and which are expected to affect low-level flights. More information about SIGMET services is provided in part GEN 3.5.8;widespread mean surface wind speeds above 30 KT; widespread surface visibility of less than 5000 M, including weather phenomena reducing visibility; clouds below FL100, including cloud amount, type, and height of the base and top;/ clouds ( TCU, TCU, TCU, ISOL CB, OCNL CB, FRQ CB);thunderstorm with and without hail (ISOL , OCNL TS, ISOL TS, OCNL TSGR);moderate or severe icing, not associated with convective clouds ( / ICE);moderate or severe turbulence, not associated with convective clouds (MOD /SEV TURB);height of 0°C level below FL100;sea surface temperature;volcanic eruption; release of radioactive materials into the atmosphere.The SIGWX charts are kept under continuous review, and amendments (AMD) are issued as necessary. In addition, AIRMET for Vilnius FIR are issued as necessary during the validity of SIGWX charts. More information about AIRMET services is provided in part GEN 3.5.8. SIGWX forecasts are distributed according to agreements with users and can be obtained from self-briefings located at EYVI, EYKA, EYPA and EYSA. SIGWX forecasts are sent by email on request from the LHMS Forecasts and Warnings Division (aviation). Warning services Warning services for aerodromes in Lithuania are provided by the LHMS Forecasts and Warnings Division (aviation), which carries out the duties of AMO. Aerodrome warnings contain a concise statement of meteorological information that can have a negative impact on parked and moored aircraft, aerodrome facilities, or impede RWY cleaning. Aerodrome warnings are issued if one or more of the following phenomena occurs or is expected to occur at the aerodrome:EYVI, EYKA, EYPA:air temperature change from positive to negative (FROST);freezing precipitation ( or );heavy rain (HVY RA); heavy snowfall (HVY SN);strong surface wind exceeding 40 KT (SFC WSPD or SFC WIND);thunderstorm 9 KM radius around aerodrome (TS).EYSA:freezing precipitation;strong surface wind exceeding 30 KT.Wind shear warnings contain a concise statement of information about the reported or/and expected evidence of wind shear at Vilnius aerodrome. The preparation of a wind shear warning and a confirmation of the warning previously issued are mainly based on aircraft reports. Information about wind shear received from ATS units is included in METAR/SPECIAL. Aerodrome warnings and wind shear warnings are prepared in abbreviated plain English using ICAO-approved abbreviations and numerical values and are distributed according to interoperability services. The validity period of an aerodrome warning is no more than 4 hours, and the validity period of a wind shear warning is no more than 1 hour. Aerodrome warnings and/or wind shear warnings will be canceled when a phenomenon is no longer occurring or is no longer expected to occur at the aerodrome. The warning is understood to automatically cancel itself at the end of its validity period. If the phenomenon persists, a new warning will be issued with the next sequence number and for a further period of validity. The numbering of aerodrome warnings starts every day at 00:01 and is separate for each aerodrome.MET information for pre-flight planningFlight documentation Flight documentation for international and domestic flights for operators and flight crew members is prepared by the LHMS Forecasts and Warnings Division (aviation). Flight documentation comprises: a significant weather prognostic chart (SWM, SWH);upper winds and air temperature prognostic charts;METAR/SPECIAL, including TREND, for the aerodromes for departure, intended landing, and destination alternate aerodromes;aerodrome forecasts (TAF) and their amendments for the aerodromes for departure, intended landing, and destination alternate aerodromes; SIGMET, AIRMET, information about volcanic ash, tropical cyclones, and space weather for all en route; area forecast for low-level flights (SWL), if appropriate. Flight documentation is sent by email on request from the LHMS Forecasts and Warnings Division (aviation). Satellite and meteorological radar data is available at on-line self-briefings located at EYVI, EYKA, EYPA, EYSA, and on the LHMS website via https://avia.meteo.lt/.Briefings and consultations Briefings and/or consultations for operators and flight crew members are provided by the LHMS Forecasts and Warnings Division (aviation) by phone +370 648 05 448 or +370 648 06 768.Information about abbreviations used for flight documentation and types of consultations is provided in AD 2.11.ChartsS–Surface analysis (current chart)T–Tropopause chartU–Upper analysis (current chart)SWH–Significant weather high chartP–Prognostic chartSWM–Significant weather medium chartW–Significant weather chartSWL–Significant weather low chartBriefing/consultationTypes of flight documentationT–TelephoneC–ChartD–Self-briefing displayCR–Cross-sectionPL–Abbreviated plain language textOther meteorological informationSpecific types of meteorological information for gliders, hot air balloon pilots, etc. can be obtained by agreeing terms for the provision of the required information with LHMS. NOTIFICATION REQUIRED FROM OPERATORSAn operator, requiring meteorological service or changes in existing meteorological services such as consultations, flight documents or any other meteorological information that is necessary for scheduled flights, shall notify the LHMS Forecasts and Warnings Division (aviation), sufficiently in advance, not later than one month before any:new routes or new types of flight operations are planned;changes of lasting character are to be made in scheduled operations;other changes, affecting the provision of meteorological service, are planned.In the case of a non-scheduled flight, the LHMS Forecasts and Warnings Division (aviation) shall be notified in advance as follows:for flights within Europe, not later than 3 hours before the time at which briefing, consultation and/or flight documentation are required;for flights outside Europe, not later than 12 hours before briefing, consultation and/or flight documentation are desired for flights outside Europe.The notification about individual flights for the LHMS Forecasts and Warnings Division (aviation) should contain the following information:departure aerodrome and estimated time of departure;destination and estimated time of arrival;flight route and cruising level;alternate aerodromes;type of flight - or ;type of meteorological information necessary for a flight crew, either flight documentation and/or briefing or consultation;time for which briefing, consultation and/or flight documentation is required.The LHMS Forecasts and Warnings Division (aviation) shall be notified by the operator or a flight crew member as soon as possible when a flight is delayed, advanced or canceled.AIRCRAFT REPORTSWhen flying through the Vilnius FIR/UIR, aircraft perform Special observations and report them to the relevant ATS unit if the following conditions are encountered or observed:Special air-reports shall be forwarded when moderate or severe turbulence, moderate or severe icing, severe mountain wave, thunderstorms, without hail, that are obscured, embedded, widespread or in squall lines, thunderstorms, with hail, that are obscured, embedded, widespread or in squall lines, heavy sandstorm, volcanic ash cloud or pre-eruption volcanic activity or a volcanic eruption are encountered;Other air-reports (non-routine) shall be forwarded when meteorological conditions (e.g., wind shear) are encountered, which in the pilot’s-in-command judgment, might have an impact on flight safety, or significantly reduce the efficiency of flights of other aircraft.Reports from aircraft in flight are reported at the time the observation is made or as soon as possible. Observation information from aircraft is always transmitted to the LHMS Forecasts and Warnings Division (aviation) by the ATS unit.VOLMET SERVICENIL.SIGMET AND AIRMET SERVICELHMS Forecasts and Warnings Division (aviation) carries out the duties of MWO, including a continuous watch within Vilnius FIR and the issuance of SIGMET/AIRMET.Name of MWO, ICAO location indicatorHours of service or servedSIGMET/AIRMET validity periodsSpecific procedures applied to SIGMET informationProcedures applied to AIRMET informationATS units providedATS units providedAdditional information12345678VILNIUS/EYVIH24Vilnius FIRSIGMET H4,VA SIGMET H6AIRMET H4 SIGMET is based on VAAC informationAIRMET are issued at 03-21 UTC, and from the last Sunday in October to the last Sunday in March - 03-15 UTC,, SIGMET, SIGMET for SEV , AIRMET for OBSC, MOD MTW are not issuedSIGMET is issued in the case of the occurrence or expected occurrence of one or several of the following significant meteorological phenomena: thunderstorm: obscured without hail (OBSC TS), embedded without hail (EMBD TS), frequent without hail (FRQ TS), squall line without hail (SQL TS), obscured with hail (OBSC TSGR), embedded with hail (EMBD TSGR), frequent with hail (FRQ TSGR), squall line with hail (SQL TSGR); severe turbulence not associated with convective (SEV TURB); severe icing not associated with convective (SEV ICE);severe icing due to freezing rain (SEV ICE (FZRA));heavy dust-storm (HVY DS);heavy sandstorm (HVY SS); volcanic ash cloud (VA CLD); radioactive cloud (RDOACT CLD).AIRMET is issued in the case of the occurrence or expected occurrence of one or several of the following significant meteorological phenomena that are not covered by the current SIGWX forecast: widespread mean surface wind speeds above 30 KT; widespread horizontal surface visibility of less than 5 000 M, including weather phenomena reducing visibility; widespread areas of BKN or OVC cloud with a height of a base less than 1 000 FT (AGL); isolated/occasional/frequent TCU/CB (ISOL TCU, OCNL TCU, FRQ TCU, ISOL CB, OCNL CB, FRQ CB); isolated/occasional thunderstorm with or without hail (ISOL TS, OCNL TS, ISOL TSGR, OCNL TSGR); moderate icing not associated with convective clouds (MOD ICE);moderate turbulence not associated with convective clouds (MOD TURB). SIGMET/AIRMET are prepared in abbreviated plain language using ICAO-approved abbreviations and numerical values. The numbering of SIGMET/AIRMET starts every day at 00:01 UTC. The sequence number of AIRMET consists of two characters, while the sequence number of SIGMET consists of three characters. The three-character sequence number is constructed using a single letter identifying the phenomenon, followed by two numeric characters corresponding to the number of SIGMETs issued for that phenomenon for the specified FIR on the day concerned. The validity period of an AIRMET/SIGMET is no more than 4 hours, except for VA SIGMET for volcanic ash cloud, which may have an extended validity period of up to 6 hours. VA SIGMET for volcanic ash clouds is based on relevant advisory information received from the Volcanic Ash Advisory Centers (VAAC) in London or Toulouse. SIGMET/AIRMET are disseminated to international OPMET data banks, SADIS, and other MWOs and AMOs. VA SIGMET are also disseminated to VAACs. OTHER AUTOMATED METEOROLOGICAL SERVICESThe purpose of the ATIS is provision of information to the arriving and departing aircraft on the current conditions in the terminal area. An ATIS broadcast contains all information necessary for a pilot to make a final decision on approaching, landing or taking-off. In ATIS decoded messages MET REPORT AUTO, the value NOT AVBL of the field CLOUD TYPE will be omitted and not broad-casted.ENR 6.03 - Index to Areas for Weather Services