NHET and rainfall in deep southern districts of TN

DUNDEE SAT IMAGERY 211114 15Z 

Once in few decades the retreating SWM gives copious rainfall in southern most tip of India.  This may be due to WEAK  SWM monsoonal winds prevailing  lower latitude close to Equator. These may be considered as Northern Hemisphere Equatorial troughs [NHET] -a prevailing pattern. Before the onset of SWM these NHET as well as SHET forms on either side of 5 Deg latitude. Similarly when SWM is withdrawing  to lower latitude the same pattern prevails.  

This NHET brought heavy to very heavy rainfall over Kanyakumari, Tirunelveli, thoothukudi districts of TN.  The cloud band below Srilankan deep south is active.