Download User Guide to ECMWF forecast products

5The forecast products
5 The forecast products
5.1 The operational schedule
ECMWF produces global analyses for the four main synoptic hours 00, 06,
12 and 18UTC, and global 10–day forecasts based on 12 UTC analysis. An additional analysis is run for 00 UTC with a cut–off time of around 3 hours, followed
by a global 3–day forecast to provide some Member States with boundary conditions to their limited area models.
5.2 Direct model output
The model variables for the computation of the forecasts are temperature,
wind and specific humidity. These primary parameters are converted into other
atmospheric parameters. Tables 5 and 6 summarize the main output of the forecast
model. These parameters are computed at 3–hourly intervals from 6 to 240 hours,
based on 12 UTC data.
Table 15: Upper air parameters
Geopotential height (not on model levels)
Temperature
Vorticity and Divergence
Wind (U and V components)
Vertical Velocity
Specific Humidity
cloud ice/water content on model levels
Upper-air parameters are produced on the original model levels and on
standard pressure levels (1000, 925, 850, 700, 500, 400, 300, 250, 200, 150,
100, 70, 50, 30, 20, 10, 7, 5, 3, 2 and 1 hPa).
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