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  • https://met.mirats.vn/

    Trung tâm Khí tượng hàng không Đà Nẵng. Dựa trên công văn số 441/KL phòng Không Lưu Công ty Quản lý bay miền Trung ngày 25/12/2019, em đã tạo tài khoản cho Trung tâm Điều hành khai thác Tân Sơn Nhất để truy cập vào website khí tượng Hàng không Đà Nẵng với:

    User: ttdhkttsn

    Pass: Ttdhkttsn2020

    Địa chỉ website khí tượng: https://met.mirats.vn/

    Sau khi truy cập vào được website với user và pass trên, bên Đội Kỹ thuật Khí tượng khuyến cáo Trung tâm điều hành khai thác TSN nên đổi pass để đảm bảo thông tin.

     

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  • Tại sao BR đc gọi là Mist trong bản tin metar ???

    There are a few things in a pilot’s life that affects him as much as the METAR.  The METAR can ground you or tell you that you’re legal to try an approach.  It’s one of those few things which follows you on every flight.  Since a pilot spends a fair amount of time reading these things, occasionally something odd pops up.  And then it nags at you.  An example of that is the METAR descriptor GR.  Why does GR mean hail?  Wouldn’t you think they’d choose HL?  Perhaps that’s too close to HELL.  And that might confuse pilots who frequently see SS (Sandstorms) DS (Dust Storms) and VA (Volcanic Ash) which I think of as forms of weather hell.

    So I decided to look at the whole list of METAR descriptors.  Here they are:

     

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  • Jetstreams

    Jetstreams thực chất những  dòng sông“ bằng khí luân chuyển trên độ cao lớn từ khoảng 10-20 km.
    Ở xích đạo nóng chảy mỡ thì khí bốc lên cao lằm tăng áp suất trên độ cao lớn (18-20km), trong khi áp suất tại mặt đất thì giảm. Còn ở cực Bắc hay cực Nam thì ngược lại, lạnh teo trym, nên áp suất không khí dưới mặt đất lớn, nhưng trên cao lại nhỏ đi.

     

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  • Pilot Reports

    Pilot Reports

    Introduction:

    • A Pilot Report (PIREP) is a report of meteorological phenomena encountered by the pilot, in flight
    • These reports serve as warnings to other pilots and give Air Traffic Control (ATC) knowledge of potential hazards in order to keep pilots clear
    • All pilots should give reports if:
      • In flight when requested
      • When unusual or unforecast weather conditions are encountered
      • When weather conditions on an IFR approach differ from the latest observation
      • When a missed approach is executed due to weather
      • When a wind shear is encountered on departure or arrival

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  • Aviation Routine Weather Report

    Aviation Routine Weather Report

    Introduction:

    • An Aviation Routine Weather Reports (METAR) is a weather observer’s interpretation of the weather conditions at a given site and time
    • Can be used to compare between observed and forecast weather, to determine if conditions are actually developing as originally forecast
    • The U.S. uses the ICAO world standard for aviation weather reporting and forecasting
    • The World Meteorological Organization’s (WMO) publication No. 782 “Aerodrome Reports and Forecasts” contains the base METAR and TAF code as adopted by the WMO member countries

     

     

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  • Surface Analysis Chart

    Surface Analysis Chart

    Introduction:

    • Surface Analysis Charts are computer-generated charts with frontal and pressure analysis issued from the Hydro-meteorological Prediction Center (HPC)
    • Found at http://aviationweather.gov/adds/progs/

     

    Surface Analysis Chart
    Figure 1: Surface Analysis Chart

    Issuance & Validity:

    • Issued every 3 hours
    • Valid Time (VT) of the chart on the lower left corresponds to the time of the observations
    • Valid time is given in UTC
    • Information is about 2-3 hours old
    • Information is all observed data

    Isobars:

    • Isobars are drawn as solid lines in order to represent pressure
    • Each interval is spaced at 4 millibars (mb)
      • hectoPascals (hPa) are the metric equivalent of millibars
    • Gradient, or pressure gradient force, is measured by how far apart the isobars are from one another
    • When the pressure gradient is very shallow, intermediate isobars (short dashed lines) are sometimes drawn at one-half the standard interval

    Pressure Systems:

    • The letter “L” denotes low pressure
    • The letter “H” denotes high pressure
    • The pressure center of each is indicated by a three or four digit number that is the central pressure in mb (hPa)

    Fronts:

    • Shows positions and types of fronts
    • A three-digit number near a front classifies it as to type, intensity, and character enclosed in brackets ([ or ])

    Troughs and Ridges:

    • A trough of low pressure with significant weather will be depicted as a thick, dashed line running through the center of the trough and identified with the word “TROF”
    • The symbol for a ridge of high pressure is very rarely, if at all, depicted

    Notes:

    • The observations from various stations are plotted
      • These are referred to as station models
    • Round station symbols indicate observations taken by an observer
    • Square station symbols indicate the sky cover was determined by an automated machine
    • Models appearing over water are data from ships, buoys, and offshore oil platforms
    • An outflow boundary will be depicted as a thick, dashed line with the word “OUTBNDY”
    • A dry line will be depicted as a line with unshaded pips or a through symbol identified with the words “DRY LINE”
    • Pressure is plotted in tenths of millibars, with the leading 10 or 9 omitted
    • A legend is printed on each chart stating is name, valid date, and valid time
    Dry Line
    Figure 3: Dry Line
    Trough
    Figure 2: Trough

    Frontal and Pressure Markings:

      • Trough:
        • An elongated area of relatively low atmospheric pressure; the opposite of a ridge
        • On HPC’s surface analyses, this feature is also used to depict outflow boundaries
      • Dry Line:
        • A boundary separating moist and dry air masses
        • It typically lies north-south across the central and southern high Plains states during the spring and early summer, where it separates moist air from the Gulf of Mexico (to the east) and dry desert air from the southwestern states (to the west)
    Tropical Wave
    Figure 5: Tropical Wave
    Squall Line
    Figure 4: Squall Line
      • Squall Line:
        • a line of active thunderstorms, either continuous or with breaks, including contiguous precipitation areas resulting from the existence of the thunderstorms
      • Tropical Wave:
        • A trough or cyclonic curvature maximum in the trade wind easterlies
    Frontal Change
    Figure 6: Frontal Change
      • Frontal Change:
        • A hash mark denotes a change in frontal type
        • The hash mark will always be drawn perpendicular to the boundaries
        • They are not drawn at “triple points” (the intersection of an occluded, cold and warm or stationary front) and where a low pressure center separates the different frontal types
    Frontogensis
    Figure 7: Frontogensis
      • Frontogensis:
        • Refers to the initial formation of a surface front or frontal zone
        • Depicted on HPC’s surface analysis and forecast charts as a dashed line with the graphical representation of the developing frontal type (the blue triangle for cold fronts, the red semicircle for warm fronts, etc…) drawn on each segment
    Frontolysis
    Figure 8: Frontolysis
    • Frontolysis:
      • the dissipation or weakening of a front
      • depicted as a dashed line with the graphical representation of the weakening frontal type drawn on every other segment

    References:


  • Winds & Temperatures Aloft

    Winds & Temperatures Aloft

    Introduction:

    • Winds and Temperatures Aloft (FBs) are computer prepared forecasts for specific locations in the contiguous U.S. and a network of locations in Alaska and Hawaii based on the North American Mesoscale (NAM) forecast model run [Figure 1]
    • “FDWinds,” now “FBwinds,” are produced in both a textual and graphical format
    • This information aids the pilot in:
      • Determining the most favorable altitude based on winds and direction of flight
      • Identifying areas of possible aircraft icing, by noting air temperature of +2°C to -20°C, and temperature inversions
      • Predicting turbulence by observing abrupt changes in wind direction and speed at different altitudes

     

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  • Terminal Aerodrome Forecast

    Terminal Aerodrome Forecast

    Introduction:

    • Terminal Aerodrome Forecasts (TAFs) are concise statements of the expected meteorological conditions within a 5 SM radius from the center of an airport’s runway complex
    • TAFs can be found on the National Oceanic and Atmospheric Administration’s website athttp://www.aviationweather.gov/adds/tafs or through use of the java tool here
      • Can be retrieved in the raw coded format or a translated format as shown in the picture below
    • TAFs and Routine Aviation Weather Reports (METARs) are very similar but deviate wind shear, temperature, icing, and turbulence groups being added to the TAF, when applicable
    • The U.S. uses the ICAO world standard for aviation weather reporting and forecasting
    • The World Meteorological Organization’s (WMO) publication No. 782 “Aerodrome Reports and Forecasts” contains the base METAR and TAF code as adopted by the WMO member countries

     

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  • Prognostic Charts

    Prognostic Charts

    Introduction:

    • Found at http://aviationweather.gov/adds/progs/
    • Portray forecasts of selected weather conditions at specific times
    • The chart is an extension of the day 1 U.S. LLSWPC issued from the same observed data base time
    • Displays forecast positions and characteristics of pressure patterns, fronts, and precipitation
    • The 36 and 48-Hour Prognostic Chart is a day 2 forecast of general weather for the conterminous United States

     

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