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Re: computation of VFR/IFR in RUC
Posted By: John Brown In Response To: computation of VFR/IFR in RUC (Douglas Swol)
Date: 24-August-07 1847Z
In Response To: computation of VFR/IFR in RUC (Douglas Swol)
VFR, IFR, etc are based on the RUC postprocessed ceiling and visibility.
At each hour, a cloud and precipition hydrometeor analysis procedure is used to combine a 1-hour forecast with satellite cloud-top information, surface METARs, radar reflectivity, and other data to obtain initial conditions for each model forecast, including cloud and precipitation. During the forecast, cloud and precipitation are predicted. In the postprocessing of model forecasts (or of initial conditions), ceiling and visibility are derived from the model output variables, then the VFR, IFR, etc., ceiling and visibility criteria are applied to get the fields of flight rules. The procedures for obtaining ceiling and visibility from the model output variables are briefly described on the RUC web site, at the link
Hope this helps...
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