A Cut-off low at 500 hPa Geopotential Height and Rainfall Events over Iraq: Case Studies

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Mohammed Abdul Raheem Jabbar
Ahmad S. Hassan


A cut-off low is a closed low with a low value of geopotential height at the upper atmospheric levels that has been fully detached (cut-off) from the westerly flow and move independently. A cut-off low causes extreme rainfall events in the mid-latitudes regions. The main aim of this paper is to investigate the cut-off low at 500 hPa over Iraq from a synoptic point of view and the behavior of geopotential height at 500 hPa. To examine the association of the cut-off low at 500 hPa with rainfall events across Iraq, two case studies of heavy rainfall events from different times were conducted. The results showed that the cut-off low at 500 hPa with a low value of geopotential height will strengthen the low-pressure system at the surface, leading to a case of atmospheric instability over Iraq and a significant amount of rain will fall if the moisture is available.

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Mohammed Abdul Raheem Jabbar, Ahmad S. Hassan. A Cut-off low at 500 hPa Geopotential Height and Rainfall Events over Iraq: Case Studies. IJP [Internet]. 2022 Sep. 1 [cited 2023 Feb. 6];20(3):76-85. Available from: https://ijp.uobaghdad.edu.iq/index.php/physics/article/view/1007


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