Explanation:

Flash floods are defined as those flood events where the rise in water is either during or within a few hours of the rainfall that produces the rise. 

• Therefore, flash floods occur within small catchments, where the response time of the drainage basin is short. 
• They are highly localized events of short duration with a very high peak. 
• They usually have less than six hours between the occurrence of the rainfall and peak flood.

Flash Flood Guidance 

• India has launched first- of-its-kind Flash Flood Guidance services for South Asian countries — India, Bangladesh, Bhutan, Nepal and Sri Lanka — to issue impact-based forecasting of floods, which are very sudden and of short duration, at watershed and also city level. 
• The Flash Flood Guidance is a robust system designed to provide the necessary products in real-time to support the development of warnings for flash floods about 6- 12 hrs. in advance at the watershed level with resolution of 4kmx4km for the Flash Flood prone South Asian countries viz. India, Nepal, Bhutan, Bangladesh and Sri Lanka.

Hence only statement 2nd is correct.