Despite a persistent east to northeast wind flow, Monday’s temperatures reached well into the 60s. Some locations along and west of the Fox river brushed the 70-degree mark. This week’s warm-up will be interrupted by two influxes of polar air. These episodes will be brief and limited, dropping afternoon readings back to the 50-degree range on Wednesday and Friday. Resurging warm air is forecast to reach the metro area over the upcoming weekend with a return of 60-degree weather. High pressure will shift east of the region by Sunday, allowing a sustained southwesterly air flow to lock in. June-level warmth over the Plains is expected to sweep across the Midwest and Great lakes as the month of April, which produced 9 days of observed snowfall over its first three weeks, draws to a close. High temperatures Monday are forecast to reach 80 degrees, making it our warmest day since October 9th of last year.