Update: City of Muntinlupa extends class suspensions in pre-school, elementary and high school tomorrow, September 24, 2013.
Muntinlupa City  has declared class suspensions in pre-school, elementary and high school today, September 23, 2013 due to the inclement weather.
Sources: https://twitter.com/officialmunti/status/381877952117354497, https://www.facebook.com/officialMuntinlupacity/posts/518250911597166