Algeria is facing an endemic drought spread over 40 years and the lack of rainfall makes us fear the worst for the country's water security. The variability in the amount of rainfall and its irregularities in time and space are the main causes of the behavior of a climatic regime.This work focuses on the analysis of climatic data provided by the google earth engine platform in order to detect temporal changes in the hydrometeorological series.The climatic results of our Mekerra watershed show a very irregular hydrometeorological system, a long dry season, an LST that reaches 54 C°, an average annual rainfall amount is 390.41 mm and a rainfall deficit estimated at 30%, a very low rainfall deficit of a maximum value of 0.42 and an NDWI globally negative.