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Most studies conducted on the desert oasis effect have focused on the summer season, while the winter has received less attention. This study aimed to determine existence of the oasis climatic effect in winter season and investigate influence of different vegetation types on its intensity and dynamics. Measurements were conducted during five consecutive years (2004-2009) at the peak of winter in a manmade oasis located in hyper-dry Arava Valley, Israel. Results obtained demonstrate that all types of vegetation had a cooling effect (up to 2 degrees C) limited to a few mid-day hours. In contrast, from nighttime throughout morning all vegetation types were up to 2 degrees C warmer than the surrounding desert. This effect was more pronounced with subtropical vegetation in comparison to local desert trees. The effect was most significant in calm, stable weather conditions characterized by low nighttime temperatures, while during unstable weather it was negligible. Influence of tree canopies on incoming and outgoing radiation is a major factor determining the influence of vegetation on local climate conditions in winter season. Since one characteristic of arid climates is extremely low nighttime temperatures during winter, warming created by the oasis has implications for human comfort and energy consumption in the desert environment. (C) 2012 Elsevier Ltd. All rights reserved.