Portersville Borough, PA

Nymphs are questing, the highest-risk stage for people. Nymphal deer ticks peak in late spring and summer. They're the size of a poppy seed, easy to miss, and cause most Lyme transmission.

Portersville Borough is 83% natural land cover (50% forest, plus open and brushy areas) across its 0.8 sq mi, home to about 224 people. That makes it the 44th-most wooded of the 57 towns in Butler County. Deer ticks live in wooded areas, along trail edges, and in tall grass — the more of that a town has, the more places ticks can quest.

Butler County reports about 175 Lyme cases per 100,000 people a year, the 85th-highest of 210 Northeast counties. That county-level disease pressure, combined with Portersville Borough's local habitat, sets how high its daily score can climb when the weather and season allow.

Yes. Nymphs are questing, the highest-risk stage for people. In Portersville Borough, today's risk reads moderate (50/100). Ticks are active. Use repellent, stick to trails, and do a tick check when you come inside.