During the third week, from April 23–30, weather conditions gradually shifted toward a more settled and milder spring pattern. After a stretch of cooler, cloudy weather earlier in the month, the period featured a mix of partly sunny to sunny days, lighter winds, and temperatures generally ranging from the upper 50s into the mid-60s, with a few warmer afternoon periods. Overnight lows remained cool, often dipping into the 30s and 40s, typical for late April north of Boston. Overall, the week provided relatively stable and favorable conditions as the peregrines continued steady full-time incubation of their four-egg clutch.

During the third week of incubation, development inside the eggs is well advanced. The embryos now resemble fully formed chicks, with distinct features such as a developed beak, talons, and feather tracts beginning to form beneath the skin. Growth is rapid, supported by an extensive network of blood vessels drawing nutrients from the yolk. The chicks are becoming more active within the egg, and subtle movements may occasionally be detected. This stage is critical, as the embryos prepare for the final phase leading to hatching, typically beginning around days 29–33.

Incubation behavior remains steady and purposeful. The female continues to handle the majority of brooding duties, maintaining consistent warmth and carefully turning the eggs to support proper development. The male remains an attentive partner by delivering food regularly and taking short incubation shifts, usually during daylight hours, allowing the female time to feed and maintain her condition. Exchanges between the pair are smooth and efficient, minimizing any exposure of the eggs to the cool spring air common north of Boston. As the end of incubation approaches, attentiveness often increases, setting the stage for the first signs of hatching in the days ahead.