This is a trend which should continue the remainder of the work week with moderate humidities—but a weather system coming together in the Rockies is eastbound and is headed toward Chicago setting stage for active thunderstorms capable of downpours and possible severe weather toward Sunday

• Here are graphics which look at the comfortable summer weather which has graced the Chicago area this week–and others which indicate how the late weekend storms are to come together.
• Satellite imagery Wednesday was tracking its shower and t-storm development in the Rockies. Atmospheric moisture projections have MUGGY 70-deg dew point air sweeping into the Chicago area—moist air which is to grow unstable as cooler air arrives and a jet stream disturbance arrive at the upper levels as early at Saturday night—but will become a potentially prolific storm cluster producer Sunday and Sunday night with scattered storms which could spill over into Monday

SET-UP FALLING INTO PLACE FOR SUNDAY STORMS —
JET STREAM DISTURBANCE

WOW! JULY WAS WET HERE!

More than a foot of rain fell at Oak Lawn and in Chicago’s Rogers Park neighborhood. Other totals off the CoCoRaHS volunteer observation network were stunning: 2 to 3 times normal at a number of locations. And, the pattern evolving as we head into August appears likely to remain wet with at least two wet systems modeled to produce potentially significant attention rain here: The first Saturday night into Monday and a second in the Wednesday night through Friday time frame if current model forecast trends verify.

IN CHICAGO DURING JULY, 2023

O’Hare wound up with an eye-catching 7.61”—195% the normal for the month of 3.90” ranking as the 7th wettest July of the past 153 years.

BEIJING, CHINA HIT WITH ITS HEAVIEST RAINS

• Beijing, China hit with its heaviest rains—more than 29”—in 140 years as the remnants of deadly typhoon Doksuri, responsible for deadly landslides in the Philippines, hits the Chinese capital.
• Imagine 29” of rain in single storm. That’s how much fell in China’s capital city of Beijing from Saturday morning through this morning. Our ENTIRE WATER-EQUIVALENT ANNUAL PRECIP TALLY here in Chicago is 37.86.” So what’s fallen in Beijing is the equivalent of more than three quarter of our annual Chicago water equivalent tally, all in 4 days.
• The torrential rains in Beijing are the latest weather extremes to impact China. This year as The Guardian reports, “China has been hit hard by extreme weather in recent months, from record-breaking heatwaves to deadly rain. In July, employers across the country were ordered to limit outdoor work due to blistering heat.”
• From the Sixth Tone site, which clears news from China, comes the following report: “Records show that 10 national weather stations in the region registered their highest daily rainfall ever recorded. Additionally, data from 14 national meteorological stations indicates that the accumulated rainfall in the past three days exceeds the usual summer total for the region.”

THE STURGEON SUPER MOON

• Not only has the full STURGEON SUPER MOON put on an incredible show for those of us here on the ground—it’s been BEAUTIFULLY CAPTURED by so many of you in the photos you’ve sent our way—but its moonlight ILLUMINATED the entire North American continent overnight, something evident on the nighttime satellite images.
• The nighttime images have been produced by one of our country’s low-orbiting POLAR ORBITING WEATHER SATELLITES—the “NOAA-20”—and were posted early Wednesday by the folks at CIMSS (the Cooperative Institute for Meteorological Satellite Studies) at the University of Wisconsin-Madison. The NOAA-20 weather satellite travels at an altitude of roughly 512 to 518 miles above earth’s surface and moves from pole to pole, photographing a swath of of our planet as it does.
• AN ACKNOWLEDGEMENT—the full moon photo you see here has come my way from Toby Large of Schaumburg. . .