Status:Ongoing analysis Material from: Linus, Esti, ..
1. Impact
In the early part of 15 January, TC Belal hit La Reunion. Also Mauritius was hit by severe rainfall related to the cyclone.
https://en.wikipedia.org/wiki/2023%E2%80%9324_South-West_Indian_Ocean_cyclone_season
2. Description of the event
3. Predictability
3.1 Data assimilation
3.2 HRES
The plots below show 1-day precipitation (14 January 12UTC - 15 January 12UTC) in observations (first plot), concatenated short forecasts (second plot) and ENS control forecasts with different lead times (all 00UTC runs). The box marks a 0.25x0.25 degree box centred on St Denis (20.9S, 55.5E).
The plots below show the same as above but for forecast (except the plot with concatenated short forecasts) for DestinE 4.4km.
3.3 ENS
The plot below shows the forecast evolution plot for 1-day precipitation (14 January 12UTC - 15 January 12UTC) in a 0.25x0.25 degree box centred on St Denis (20.9S, 55.5E) . Concatenated 6-hour forecasts - green dot, ENS control –red, DestinE4.4km - purple, ENS blue box-and-whisker, Model climate – cyan box-and-whisker. Ensemble mean as black diamonds. Triangle marks the maximum in the model climate based on 1800 forecasts (to be added).
The plots below show the tropical cyclone track for TC Belal for the operational ECMWF forecasts from 15 January 00UTC (first plot) to 8 January 00UTC (last plot). The symbols shows the position on 15 January 00UTC (hourglass for BestTrack). HRES (red), ENS CF (blue), ENS PF (grey) and BestTrack (black).
3.4 Monthly forecasts
3.5 Comparison with other centres
3.6 Machine-learning models
The plots below shows MSLP and 850hPa wind speed valid 15 January 00UTC from different lead times.
IFS
AIFS
Graphcast
PanguWeather
Fourcastnet
FuXi
ML centres comparison
4. Experience from general performance/other cases
5. Good and bad aspects of the forecasts for the event