Winds off Lake Michigan much of the past week led to a colder-than-normal end to April. High temperatures Friday reached the low 70s across inland suburban locations, while holding in the low 50s along Chicago's lakefront. With high pressure moving east of the area, a wind shift to the southwest will allow warmer air to overspread the area. As winds strengthen Saturday, lake-cooled air is expected to remain offshore. High temperatures along area beaches are expected to increase 20 to 25 degrees over Friday's readings, with highs peaking in the mid-70s. The warming trend is forecast to continue much of the upcoming week. As southwest winds persist into Monday, dew point temperatures will rise to the low 60s, increasing the likelihood of thunderstorms across the area.