Big warm-up today—more like mid-April

High temperatures will push 60° as the January 2006 mild spell peaks this afternoon. Climatologically, average highs in the mid to upper 50s are not reached in Chicago until mid April. Winter 2005-06 has been extremely unusual with a dramatic temperature reversal from early December to early January. Average temperatures the first 11 days of December averaged 17.6°, some 4.4° below the normal readings for the first 11 days in January. In stark contrast, the first 11 days of January have averaged 36.0°, some 6.3° above the Dec. 1-11 normal. It’s been 67 years (1939) since a January has started out this mild. Illinois is primed to be the recipient today of an air mass that produced record highs of 72° in McCook, Neb. and 70° at both Dodge City and Goodland, Kan. Computer models project a continued mild weather pattern, only interrupted by brief cold air intrusions Friday and next Wednesday.