The Grand Ayatollah Fayyaz answered a question about fasting in Karbala without having the intention of staying in Karbala for 10 days.
Question: Considering that it is allowed to perform full Salaat in Karbala, is it possible to fast in Karbala without having the intention of staying there for 10 days?
The Grand Ayatollah Fayyaz: This decree is especial to Salaat in areas around the holy shrine and does not include fasting.
source : shafaqna