Global positioning systems (GPSs) have become a powerful remote sensing tool to estimate the water vapour in the troposphere. This study describes the operational processing of the Moroccan ground‐based GPS meteorology stations. It presents the evaluation of the accuracy of zenith tropospheric delay (ZTD). The accuracy is evaluated first in relation to the International Global Navigation Satellite System Service (IGS) final products, and second by comparison to equivalent values derived from radiosonde profiles. The comparison of near‐real‐time ZTD with the IGS final product shows a bias of −1 mm with a standard deviation of 6 mm. The comparison with radiosondes shows a bias of −2.82 mm and a standard deviation of 14.01 mm. Also, the comparison of GPS ZTD and radiosonde ZTD time series over almost 1 year (2016) shows good agreement and a seasonal signal with higher values of ZTD in summer.

Satellites are uniquely capable of providing uniform data coverage globally. Motivated by such capability, this study builds on a previously described methodology that generates numerical weather prediction initial conditions from satellite total column ozone data. The methodology is based on two principal steps. Firstly, the studied linear regression between vertical (100hPa-500hPa) Mean Potential Vorticity (MPV) and MetOp/GOME2 total ozone data (O3) generates MPV pseudo-observations. Secondly, the 3D variational (3D-Var) assimilation method is designed to take into account MPV pseudo-observations in addition to conventional observations. After a successful assimilation of MPV pseudo-observations using a 3D-Var approach within the Moroccan version of the ALADIN limited-area model, the present study aims to assess the dynamical behavior of the short-range forecast at upper levels during heavy precipitation events (HPEs). It is found that MPV assimilation offers the possibility to internally monitor the model upper-level dynamics in addition to the use of Water Vapor Satellite images.