Precipitable Water Vapor Forecasting

ForO (Forecasting the Observatories)


WRF 3.8

The concept of ForO

 

The concept of Forecasting the Observatories (ForO) arises from the need of an accurate forecasting of the Precipitable Water Vapor (PWV), which severely impacts observations at Infrared wavelengths, at the observatories managed by the Instituto de Astrofisica de Canarias (IAC): Observatorio del Roque de los Muchachos (ORM) and Observatorio del Teide (OT). Such forecasting has been implemented as a platform running a mesoscale Numerical Weather Prediction (NWP) model, the Weather Research and Forecasting (WRF) model (currently version 3.8 in the ForO operational system). This platform includes full monitoring of the WRF model execution and easy interaction with the user through a integrated web front-end.

ForO runs the WRF model four times a day (at 00, 06, 12 and 18 UTC) providing 72 hours forecasts for the PWV above ORM and OT, following the schedule shown in the next figure:


Independent WRF model runs are executed for each astronomical site to provide specific PWV forecasts above each observatory. The WRF model in ForO uses the output of the Global Forecasting System (GFS) global model as initial and boundary conditions every 3 hours through the whole forecasting range.