Thread by @althecat

#ExtremeWeather #Emnati #TCEmnati Update:

Recent @NOAA GFS simulation model runs for #Emnati are continuing to show the storm turning towards the south as it is north of Reunion island which would mitigate the worst threats to #Madagscar.

Impact comment from RMSC/@MeteoFrance

The model guidance though is unclear (image below shows latest @ECMWF model landfall solution). The numerical model guidance is discussed from the same @MeteoFrance advisory issued at midnight.

The official track still shows catastrophic landfall in #Batsirai affected areas.

@ECMWF @meteofrance Spaghetti ensemble runs below for GEFS (L) and EPS (R) (right).] These show the current trajectory disagreement clearly.

[HT to @WXNB_ : ]
As he says an improved impact outcome for Madagascar will likely mean a worse result for La Reunion.

While the JTWC is once again inaccessible. Here is the latest 3am UTC forecast update for #Emnati #TCEmnati [Via @eggwardjwx an helpful account which provides an automated WX data feed which is worth a follow]

The JTWC update is based on microwave data - which was not available to RSMC.

Another very useful website is here >> tropicaltidbits.com/storminfo/ developed by Dr Levi Cowan aka @TropicalTidbits who is working at the JTWC. His GEFS Ensemble Spaghetti is here.

This track chart "Global + Hurricane Models" shows the current "numerical" model divergence issue very clearly.

To add to the confusion there is a third model map here which shows a significantly more northerly landfall on Madagascar. All of which explains why the JTWC is so important in this global forecasting effort.

The "Forecast reasoning" is always the most interesting part of JTWC's regular product output - and here the advisory is stark - track forecast confidence beyond 72 hours is now "Low" due to an "exponential" split in model guidance for #Emnati illustrated in the 3 charts above.