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