Completing the Flat
It looks like the STI wishes to strictly comply with the Elliott Wave Principle rules. The rule for a Flat is that it has 3-3-5 subwaves. The latest Flat is formed by Subwave A which is a WXY formation and Subwave B which has three smaller subwaves (actually it is an inverted Flat), Now Subwave C is forming the five-subwave branch, with four completed and the fifth just started today (labelled 1 to 5 in black). If this is the case, we shall see the STI plunging below the bottom of Minor Subwave 3 (black) as shown.
There is no guarantee that the STI will stop its correction after completing Minor Subwave 5 and hence finishing Wave Y (red). Corrective waves have a terrible habit of enlarging, as the STI has done by enlarging the first Flat (Wave W) with another Flat (Wave Y). It is possible that it could add on a Wave X and then Wave Z, to form a long WXYXZ correction. The rain clouds and war clouds could get worse.