Guatemala is six hours behind GMT and in the same time zone as U.S. Central Standard Time. Hours of daylight do not vary greatly between seasons, but daylight saving time is sometimes observed, depending on the whims of individual governments. It was observed in the summer of 2006 but not in 2007. Check locally for the latest.
Nearly all outlets are 110 volts, 60 cycles with outlets for plugs consisting of parallel flat blades just like the ones found in the United States, Canada, and Mexico. Power outages and electrical surges are common in rural areas, especially during unusually arid dry seasons or very wet rainy seasons in thunderstorms. Be extra careful with sensitive equipment such as laptop computers.
Like the American and European influences on its culture, Guatemala uses a sometimes confusing mixture of weights and measures from both the metric and old English systems. Fruits and vegetables are weighed by the pound, but folks weigh themselves in kilos; gas is dispensed in gallons but distances are computed in kilometers, and so on and so forth.
Another commonly used distance measurement is the vara, equivalent to 0.84 meters or a little less than a yard. For measuring land areas, the manzana equals about 0.7 hectare or 1.7 acres and the caballería covers a little more than 45 hectares or 111.5 acres. The quintal is widely used for weighing coffee and is the equivalent of 46 kilos.