Chilly east winds off Lake Michigan are as much a part of spring in Chicago as the increase in daylight for which the season is known.
Warmer air has actually made an effort to back into Chicago from the east overnight—a development most evident in areas and west and south of the city which are NOT immediately downwind of Lake Michigan.
With the latest wet spring storm tracking south of Chicago and pulling some of the system’s deeper moisture along with it, the chances for breaks in the clouds will increase Saturday afternoon and it’s likely sunshine may become quite abundant here Sunday.
Lake fog a possibility as moist easterly winds travel out over cold lake waters then ashore
The potential for patches of fog is real along Lake Michigan Saturday. The day’s east to southeast winds originate in Indiana and Michigan—areas expected to warm into the 70s—but even more importantly, a region in which dew points, a measure of moisture in the air, are in the low 50s. All that's needed to encourage fog formation is to find a way to cool that air to the low 50s. The fog and haze forms as moisture in the lake-cooled air begins to condense into water droplets.
Of course, with winds flowing out over the chilly 40-degree lake waters, cooling this air to its dew point will occur, a development which may well lead to fog formation Saturday.
Pollen count worsens; tree pollen soars to 2013 high Friday
Allergy sufferers are well aware that the 2013 season is off to a bad start, a situation underscored by Friday’s high counts in the Chicago area. Especially troublesome was the day’s tree pollen count which reached its highest level of 2013, reports Gottlieb Memorial Hospital’s Dr. Joseph Leija.
Heavy April rains led Dr. Leija to predict the potential for a “miserable” allergy season back on the 12th of last month—a forecast which has verified as pollen counts have worsened.
Friday’s 47 was the chilliest May 3 temp here in 56 years and equal to March 16’s normal high
A chill, in stark contrast to the past week’s 80s on Tuesday and Wednesday, continued Friday. The day produced a high of only 47-degrees making it the coldest May 3 in 56 years—since a 47-degree high on the date in 1957. The reading was not only 19-degrees below normal, it equaled the normal high temperature which occurs on March 16.
Wet storm being deflected south; rain slated for the Kentucky Derby Saturday evening
The sluggish-moving "cut-off" upper atmospheric storm system, a truly prolific rain producer to Chicago’s west and south Friday, continues its slow east/southeast drift Saturday and is threatening Saturday evening's Kentucky Derby with rain.
The storm generated huge rain tallies over Missouri and sections of downstate Illinois Friday. Festus, Missouri was hit with 3.60” of rain while 3.10” fell at Sullivan, MO; 3.07” came down at Medora while 3.02” was measured at Beverly—both in Illinois. Other totals Friday included 3.00” at Oakville, MO; 2.90” Mt. Sterling, IL; and 2.71” at Weldon Spring, MO.
Heaviest Chicago-area rains topped 0.60”
Rainfall Friday in the Chicago area wasn’t as extreme—but was significant nonetheless. 0.74” fell at Algonquin; 0.71” Union; 0.68” Harvard; 0.62” South Elgin; 0.60” DeKalb and 0.48” at Crystal Lake. Streator picked up 0.65”.
System’s backside snows continued to set records Friday; Minneapolis’ 0.5” tally ranks as that city’s biggest late-season accumulation in 67 years
The snowfalls recorded in recent days in a corridor from Tulsa, Oklahoma north to Rice Lake and Montreal, WI, have been May record-breakers.
Minneapolis’ 0.5” accumulation Friday was added to the list of cities in which the snow produced new records. That amount is the greatest to occur in the Twin Cities area in the 67 years since 2.8” fell on May 11, 1946.