The study compared extreme floods on the Hanjiang River and Weihe River from 1960 to 2000. Both rivers had similar flood patterns, with major floods linked to heavy autumn rains in Southwest China. Extreme floods didn't always coincide with extreme rainfall years, but often occurred just before or after. Floods in the Hanjiang River happened earlier in the year than in the Weihe River, while autumn floods came earlier in the Weihe River. These findings can help improve weather forecasting and flood control in these regions.