Complex sentence: Microbursts are very small with winds extending up to 2.5 miles (4km) and macrobursts are large-scale downbursts with winds that extend in excess of 2.5 miles (4km).
Split into simpler sentences: Microbursts are very small downbursts with winds that extend up to 2.5 miles (4km) from its source. While macrobursts are large-scale downbursts with winds that extend in excess of 2.5 miles (4km).