"Frost Advisory" Tonight and Early Sunday Morning

Canadian high pressure is centered over Dubuque Iowa, and dominates all of the mid west. The wind is calm, skies are clear, and dew points are in the mid to upper 30's. The dew point will be reached shortly after midnight with dew forming first, and patchy fog in low lying rural areas. With the air saturated close to the surface heavy dew will change to widespread frost later tonight as temperatures fall into the lower 30s before dawn.  Frost will linger past 7 am, but will melt off in most areas by 8 am.  High pressure will slip slowly southward across western Illinois on Sunday. Skies will be sunny with light winds, and a the afternoon temperature will top out in the middle 60's.  This huge high pressure ridge will move ever so slowly to the east during the week.  Skies will be sunny through Thursday, and mostly sunny on Friday.  The next chance of rain will be on Saturday as the next system from the west starts edging in from the plains.  Temperatures will  get a little warmer each day all week starting out in the low 70's on Monday reaching the low 80's by Thursday and Friday.