Kilauea is erupting again, with lava fountains shooting hundreds of feet into the air — a dramatic sight for viewers, but a health concern for people living downwind.

• The 54th round of fountaining in the ongoing eruption has started inside the Halema'uma'u crater.
• The north vent is throwing lava more than 300 feet up, and the fountains are expected to grow taller over the next few hours.
• Heavier chunks of rock should land near the vents, so the main risk stays inside the park.
• Fine ash and Pele's hair — thin strands of volcanic glass — can drift much farther and irritate eyes, skin, and lungs.

Outlook: The fountaining should peak within hours and then die down, with another episode likely to follow in the weeks ahead.