CHILLY WEEKEND AHEAD WITH DAYTIME TEMPS MORE TYPICAL OF MID MARCH THAN LATE APRIL

Twenty-two degrees cooler this weekend than last, and expect the cool pattern setting up to last through next week, the following weekend and into the weekend which follows, taking us into early May

• Only 16% of April 22nds (Saturday’s date) have produced daytime highs which rise no higher than the 40s. Yet, that’s what’s expected Saturday and Sunday. The normal temps on March 17th are 48 and 31, and the forecast for this Saturday (4/22) is 47 and 33—just about as chilly.
• The persistence of the cool weather is the product of another of these REX BLOCKS, where abnormally mild air aloft over northern Canada traps cool air over the Midwest. Blocking patterns aloft slow the progression of weather systems BIG TIME.
• The last REX BLOCK which impacted our weather was a week ago when we were in abnormally mild air. We were delighted to have a blocking pattern at work then, because we were enjoying the year’s first run of truly warm weather.
• THIS TIME, we’re to find ourselves in cooler than normal air. Temps this week will finish close to three degrees below normal—but next week is to average more than 8 degrees below normal. The week which follows, which IS showing some signs in model forecasts of starting to warm later that week, is still to come in just under 2 degrees below normal.

SHORT TERM

• What’s been happening to our West, in the western Midwest and Plains—where a good deal of cloudiness has developed along with spotty instability showers brought on by daytime heating—is a guide to what our Chicago weekend weather will look like. We will likely open dry with some clouds Saturday and Sunday—only to see what passes for daytime warming, destabilizing the atmosphere and promoting clouds and widely scattered shower development in the late mornings and/or afternoons. Those showers will fade out as temperatures cool Saturday night.
• The air aloft is to be quite chilly over the weekend with temps within a mile of the ground and in the low 20s. Thus, it’s possible a few small hailstones may form with some of the showers and make it to the ground during the spotty showers.

FOLLOW MODELED SHOWER DEVELOPMENT SATURDAY

Hourly forecast panels starting 7 AM Saturday

• The UPPER AIR FORECAST for 7am CDT Saturday. Shaded is the region in which colder than normal temps are predicted
• 7am CDT Sunday UPPER AIR FORECAST–Showing much of the Midwest beneath a large cold air pool aloft. In such a position, the rate temps drop with height increases. The atmosphere is said to be “UNSTABLE”. Clouds and scattered showers proliferate with daytime heating in such an air mass.
• 7pm CDT SUNDAY UPPER AIR

SNOWIEST SEASON ON RECORD FOR DULUTH, MN

• More than 11.5 feet of snow since last October — normal full season snowfall: 90.2 inches
• Snowfall records for the Duluth area go back to 1885, or about 137 full seasons of history as of the 2022-2023 winter. Snowfall observations have been taken at the property now known as the Duluth International Airport since 1941, with various locations closer to lake Superior before this time period.