Search results
Results from the WOW.Com Content Network
A typical METAR contains data for the airport identifier, time of observation, wind direction and speed, visibility, current weather phenomena such as precipitation, cloud cover and heights, temperature, dew point, and barometric pressure. This information forms the body of the report, consisting a maximum of 11 groups of information.
Although this coded data is still available from three American universities it has now been replaced by a universal digital coding system so data can be shared in the same format whatever the source of the observations. This enables Synop, Metar, upperair and satellite data to be processed by a common computer system.
Data collected by land locations coding in METAR are conveyed worldwide via phone lines or wireless technology. Within many nations' meteorological organizations, this data is then plotted onto a weather map using the station model. A station model is a symbolic illustration showing the weather occurring at a given reporting station. [28]
Airport observations can be transmitted worldwide through the use of the METAR observing code. Personal weather stations taking automated observations can transmit their data to the United States mesonet through the use of the Citizen Weather Observer Program (CWOP), or internationally through the Weather Underground Internet site. [7]
In the United Kingdom, when the observation is taken from an automated weather observation site, the shape is a triangle. [10] If the shape is completely filled in, it is overcast. If conditions are completely clear, the circle or triangle is empty.
The irregularly spaced observations are processed by data assimilation and objective analysis methods, which perform quality control and obtain values at locations usable by the model's mathematical algorithms (usually an evenly spaced grid). The data are then used in the model as the starting point for a forecast. [51]
A TTF is a professionally considered forecast for weather over a two-hour period, [1] and is based on an actual weather report, such as a METAR or SPECI and appended to the end of it. [1] A TTF is similar to or sometimes in addition to a TAF, a terminal aerodrome forecast, but during the TTF's validity period is considered superior to a TAF.
BUFR was created in 1988 with the goal of replacing the WMO's dozens of character-based, position-driven meteorological codes, such as SYNOP (surface observations), TEMP (upper air soundings) and CLIMAT (monthly climatological data). BUFR was designed to be portable, compact, and universal.