An assessment of the Extreme Precipitation Events (EPEs) is important because of their potential impacts on the local livelihood, ecosystem, and water resource management. In the present study, the EPEs are defined by applying a non-parametric (95 th percentile) approach over different climatic regions of Saudi Arabia using observed daily precipitation data for the period 1984-2016 obtained from 27 meteorological stations. The frequency, composite and correlation analyses are performed to evaluate the statistics of EPEs and their teleconnections. During the wet season (Nov-Apr), the frequency of the EPEs (≥25 mm/day) are higher over northeastern, central and southwestern coastal parts of Saudi Arabia. The composites and correlation analyses show that the EPEs over Saudi Arabia are associated with mid-latitude circumglobal wave train (CGT), which evolves a few days before the onset of EPEs and decays afterwards. The CGT modulates the upper-level trough over the Arabian Peninsula (AP) along with the surface anomalous low-pressure system that enhances moisture convergence, favoring the occurrence of EPEs over the region. The EPEs over Saudi Arabia are also associated with El Niño Southern Oscillation (ENSO), which shows that during the positive (negative) ENSO phase the frequency of EPEs increases (decreases) over the country. Moreover, the El Niño (with positive CGT) enhances the EPEs frequency over Saudi Arabia while vice-versa happens for La Niña (with negative CGT) phase.

Madden-Julian Oscillation (MJO)-like disturbances with features similar to observations, although slightly weaker. Conclusions The Saudi-KAU CGCM ability to simulate the ENSO and the MJO suggests that it is capable of making useful predictions on subseasonal to seasonal timescales.

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This paper describes a convective system, which brought heavy rainfall leading towards a flash flood on November 25, 2009, over Jeddah city and its surrounding regions. Meteosat Second Generation Spinning Enhanced Visible and Infrared Imager (MSG-SEVIRI) based near-real-time MSG-RGB (red, green, blue) composites and cloud top temperature images are used for the assessment of convection stages during the event. Tropical Rainfall Measuring Mission (TRMM) data is used to quantify the rainfall amount and found reliable as compared with ground observations. Air mass RGB serves as an effective tool for the visual enhancement of cumulonimbus (Cb) clouds as well as differentiating them from other local features. Cloud top temperatures obtained from MSG IR10.8 channel show that the threshold values of cloud top below 220 K can lead to rainfall with the intensity of 10 mm/hr or above over Jeddah region. The results from MSG-SEVIRI and TRMM satellite data show that satellite data could serve as an effective tool for the near real-time monitoring of the rainfall event, when analysing convection stages. The study suggests that where ground measurements are minimal, satellite information can be used in as part of a flood warning system to minimise the aftermaths of a flood disaster.