Professional information about meteorological conditions in the world
WEATHER MODEL FORECAST
Ogimet users guide
Database at Ogimet stores alphanumeric meteorological reports, i.e. alphanumeric text data, no graphic formats. Most important of them are synop reports and metar reports. These reports are from meteorological services around the whole world. They are released using specific lines for international interchange proposes. Remember that weather don't know about country borders. Some servers or Institutions in the Internet, most remarkable NOAA, selects a subset of free data and made it available in the Net. Ogimet collects these reports and use them to display the data in a easy and professional way
About forecast maps, Ogimet downloads a selection of data from GFS (Global Forecast System). Data are in grib format. Then some maps are plotted. Ogimet plots maps daily from 00 and 12 UTC runs. The maps cover all the world, some areas more detailed. They became available about 8 hours after initial model run time, (about 08 and 20 UTC)
(Here still lacks some paragraphs. This page is still building, sorry by inconvenience)
Metar's color is a color which intend to give an easy whole code about horizontal visibilty and cloud ceil in a station or airport. Horizontal visibility is the distance from where certain objects and bodies are visible. Cloud ceil ia an aeronautical term that means the level over ground with more than half sky covered by clouds. In other words, a plane flying over the cloud ceil will see less than half ground surface. Cloud ceil term is different to cloud top, which is the top level of a cloud layer
Then, taking into account horizontal visibility and cloud ceil, the color is assigned to an airport according with the following rules
As commented above, basic data is in grib format. It is downloaded from nomad3 server at NOAA. This format stores the results of meterorological fields in a very compact and efficient way. This fields in grib format are contourned and plotted with de aid some free packages, as GMT, the one used at Ogimet. Currently, there are three kinds of maps at ogimet. Projection used is orthographic. There are generic maps for Polar, Medium Latitude and equatorial zones. They covers all the world. Some specific zones are plotted with some more details. You can ask for some zone to be included freely in the named zones
In this kind of map, there are plotted 5 fields or meteorological variables:
Here, 3 meteorological variables are plotted. First one is geopotencial (altitude) of the 850 Hpa Pressure Surface. Units are geopotential Decameters (see prior paragraph about geopotential units). They are plotted at 6 ó 3 Dm intervals with a solid white line, depending on the scale of maps, the former for named zones. This is the Flight level 050 (FL050). Lower geopotential is the same that would be lower pressure at sea level. When the wind intensity is over 20 Knots threshold, it is plotted with sticks sized depending of the intensity of wind. You can see the size reference in the right of map area. Finally, the temperature at this pressure surface is plotted with colors according to the lateral scale. The temperature contour lines are black dashed lines
The interpretation of this kind of maps is the same that the 850 Hp ones. This is now the 500 Hpa Pressure surface, or the Flight Level 180 (FL180). The wind threshold is 30 Knots
DISCLAIMER: The information in these pages must be taken as merely informative. The authors are not responsible about errors, delays or failures in the data or when interpreting the data. No any critical mission should use this data.
© Copyright G. Ballester Valor 2005-2013.