1 Japan Meteorological Business Support Center, Tokyo101–0054, Japan; k–

2 Atmosphere and Ocean Research Institute, University of Tokyo, Kashiwa 277–8564, Japan;

3 Meteorological Research Institute, Japan Meteorological Agency, Tsukuba 305–0052, Japan; ksaito@mri–

4 National Center for Hydro–Meteorological Forecasting, Hanoi 10000, Vietnam;;

5 Aero Meteorological Observatory, Hanoi 10000, Vietnam;;

*Correspondence: k–; Tel.: +81–3–5577–2178


On 9 December 2018, a heavy rainfall event occurred in central Viet Nam, and at Da Nang, a record–breaking rainfall of 972 mm was observed in 24 hours. The operational precipitation analysis at the Viet Nam Meteorological and Hydrological Administration (VNMHA) on the day considerably underestimated the intense rains. We checked causes of underestimation and modified the precipitation analysis by revising the use of observation data from Automated Weather Stations (AWS) and meteorological radar data. Since the cloud top height of the precipitation system was not high, satellite precipitation estimates using Himawari–8 data drastically underestimated intense rains around central Viet Nam. GSMaP on the day detected the intense rains to a certain extent, and their rainfall estimates (GSMaP_MVK and GSMaP_NOW) were applied to precipitation analysis as alternative satellite estimates. The revised precipitation analysis showed much better representation of the precipitation system. Verification of three precipitation estimates (Himarari–8, GSMaP_MVK, and GSMaP_NOW) against AWS observation was conducted. GSMaP products clearly outperformed precipitation estimates by Himawari-8, though their standard product (GSMaP_MVK) was better than the real time version (GSMaP_NOW).


Cite this paper

Saito, K.; Hung, M.K.; Hung, N.V.; Vinh, N.Q.; Tien, D.D. Heavy rainfall in central Viet Nam in December 2018 and modification of precipitation analysis at VNMHA. VN J. Hydrometeorol. 2020, 5, 65-79.


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