Wet and cold weekend ahead
Chicagoans welcome more moderate temperatures while casting a nervous eye toward a California storm expected to roll into the Midwest later Saturday and Saturday night—then linger into Sunday
The area’s short-term weather concerns revolve around a disturbance which arrives later Thursday and produces drizzle predicted to build into steadier rain Thursday night.
Storm threatens snow, flooding rains and severe weather over nation’s mid-section; arctic chill to send temps plunging later Sunday into Monday
The stronger weekend storm system is to follow late Thursday’s disturbance into the Chicago area amid strengthening easterly winds Friday and Saturday. The system is a moist one. Rainfall is to begin later Saturday and Saturday night on top of a 3 to 6” snowpack. The rain may become an issue—particularly in the area south of I-80. That’s because the top layer of soil has frozen in the abnormally cold pattern which has dominated much of December. The frozen layer of top-soil prevents percolation of moisture into the soil. This produces “run-off” which winds up in area rivers, many of which are extensively frozen. Any break-up of the ice there may produce ice jams which can produce or aggravate flooding.