Pandan has a total land area of about 126.1 square kilometers or 14,628 in hectares based on official boundaries. These account for about 6.12 percent of the total land area of the province. Of this area, 70.52 percent or 10,316 hectares are classified as uplands, with slopes of more than 8 percent, and the remaining 29.48 percent or 4,312 hectares are classified as lowlands.
The municipality of Pandan is a mixture composed of flat and hilly terrain. The central arid northwestern coastal are level to nearly level, the rest of the northern part from slightly to strongly rolling. The northeastern part is strongly sloping or strongly hilly to mountainous.
Philipines has two types of climate, dry and wet season. Pandan is a town in the province of Antique in the Philippines and it also has the same climate, dry and wet season. Dry season is normally from December to May and wet season is from June to November. But it could rain any month of the year. Heavy rains could occur from July to September. During rainy season, there could be storms as well. December to January are cold months in the Philippines.