PWV forecasts for Paranal from the GFS model

Home | Search | Verification |

GFS forecasts at 00, 06, 12 and 18 UTC will be available about 4.5 hours later

PWV forecasts from the GFS model for the next 5 days. Forecasts start at the day and hour shown in the figure title. From that time, 3-hourly PWV forecasts for the next 5 days (120 hours) are plotted. Vertical red lines limit each one of 5 days of forecasts. The GFS model is run 4 times per day at 0, 6, 12 and 18 UTC. The figure is updated 4 times per day as soon as outputs from the new model run are released. A .txt file with PWV forecasts is also available.

PWV Forecast


Ascii file description

The ascii file contains 4 columns of data that represent: [Date of forecast initiation, Hour of forecast initiation, Forecast hour, PWV forecast]

Ascii File




Statistics for the last 7 days of forecasts

The figure shows the comparison between PWV forecasts during the last 7 days and PWV from VLT radiometer. A legend is displayed showing the colors used for VLT instruments and the GFS forecasts. Vertical black lines limit the 7 days of analysis. The first panel shows the PWV forecasts initiated every day at 00 UTC. The black line represents VLT instruments during the 7 days. The blue line represents the GFS forecast initiated 7 days earlier at 00 UTC, extending for the next 5 days. It is displayed in the legend as GFS-7d. Each color represents the new forecast initiated the next day. This continues until the grey line that represents the GFS forecast initiated 1 day earlier at 00 UTC, extending for only 1 day until present day. It is displayed in the legend as GFS-1d. The second, third and fourth panels show the comparison of PWV forecasts initiated at 6, 12 and 18 UTC, respectively, with VLT instruments.



Same as the previous figure but for the bias (model-obs)