Channelling flows in the Hunter Valley
Christopher Webb A and Jiwon Park
B *
A Formerly at Williamtown Weather Services Office, Bureau of Meteorology.
B NSW and ACT Decision Support Service, Bureau of Meteorology, Sydney, NSW, Australia.
Journal of Southern Hemisphere Earth Systems Science 73(2) 194-211 https://doi.org/10.1071/ES22021
Submitted: 17 July 2022 Accepted: 19 July 2023 Published: 1 August 2023
© 2023 The Author(s) (or their employer(s)). Published by CSIRO Publishing on behalf of the Bureau of Meteorology. This is an open access article distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND)
Abstract
The Hunter Valley is well known for the strong westerly winds in winter and elevated fire danger arising from hot and dry north-westerly winds in summer. These hazards are closely related to the valley channelling in the region, and the connection between the two has been an interest to weather forecasters, emergency service personnel, and the aviation industry. In this paper, the climatology of valley winds is constructed to identify the dominant types of channelling in the Hunter Valley and their preferred directions using the 10-year data of Automatic Weather Station observations, upper air sounding and ERA5 reanalysis data between July 2010 and June 2020. Particular attention is given to the conceptual model of pressure-driven channelling of westerlies in winter and its mechanics, as the climatology shows that it is the main cause of wind-warning conditions in the Hunter.
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