Understanding the variability of changes in cosmic rays (CR) is critical for a variety of applications, including space weather research, changes in atmospheric chemistry, climate change studies, and more recently, biological and medical research The rate of CR detected on the ground depends on many meteorological factors. To understand the properties of these CRs, corrections must be made for local variations in these factors. Atmospheric pressure and temperature are the most effective factors affecting the rate of CR muons. King Abdulaziz University (KAAU) Jeddah, Saudi Arabia. (Rc = ~14.8 GV) set up a single-channel muon detector for CR fluctuation studies. In this study, we investigated the effects of atmospheric pressure and air temperature on the detected CR using the first available data obtained from the KAAU muon detector Generally, we have found that the atmospheric pressure and temperature are inversely correlated with the muon rate. However, this is not always true, we have found that in certain occasions that the increase in atmospheric pressure and air temperature increase the number of the detected CR muons. The exact explanations of such anomaly are yet to be determined. Nevertheless, the impact of other meteorological variables as well as the considerations belong to the site rigidly may be a possible explanation.