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

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

*Correspondence: k–; Tel.: +81–3–5281–0440 


Development of forecast guidance is one of the main activities of Output 3 of the JICA project to improve forecasting services of VNMHA. We applied the Kalman filter (KF) technique by using a calculation package which was provided in the JICA group training course in meteorology by the Japan Meteorological Agency (JMA) to Vietnam for the development of temperature guidance. Maximum and minimum temperature guidance was developed for 63 cities up to 3 days ahead using JMA Global Spectral Model (GSM) Grid Point Value (GPV) data and up to 10 days ahead using ECMWF Integrated Forecasting System (IFS) GPV data. Verification results show that Root Mean Square Errors (RMSEs) of GSM and IFS KF guidance are relatively large in the northern region in both maximum and minimum temperatures, but KF guidance greatly reduces RMSEs of direct model outputs in all regions throughout the year. RMSEs of IFS guidance become smaller than those of GSM guidance with increasing forecast time. Averaged RMSEs of KF guidance for 63 cities are smaller than those of city forecasts issued by forecasters in Nov–Dec 2019 and Jan–Feb 2020. These verification results suggest that accuracy of maximum and minimum temperature city forecasts will be improved by using KF guidance in daily forecasting.


Cite this paper

Sasaki, K.; Anh, V.T.; Hang, N.T.; Trang, D.T. Development of maximum and minimum temperature guidance with Kalman filter for 63 cities in Vietnam up to 10 days ahead. VN J. Hydrometeorol. 2020, 5, 51-64.   


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