Rockford Scanner™: Update On Todays Weather. Storms,Funnels and Fog



 

 

 

SHORT TERM...
242 PM CDT

Through Tonight...

The main items of note for the short term forecast are scattered 
showers and a few storms continuing into early evening along with 
the potential for overnight and early morning fog.

The broad surface low and a fairly broad parent mid-level trough 
are slowly drifting east across the mid-Mississippi Valley this 
afternoon. Forcing for ascent within a high absolute moisture and
non-capped airmass are generating convection, but limited focus 
and moisture transport/replenishment are keeping showers 
scattered. Envision this trend continuing through early to mid- 
evening, especially as a mid-level vorticity maximum in northwest 
Illinois per water vapor imagery shifts east over the area. This 
feature may continue showers and even a storm or two into the 
overnight. 

Locally heavy downpours with the slow-moving cells will continue 
to be common, but the convection has not been deep enough to 
warrant any concerns on flooding. Also, a chance for a
funnel cloud or two in north central Illinois and points west
through early evening, given high values of low-level CAPE and 
vorticity.

The combination of the showers, residual high dew point air around
70, and the passage of the broad surface low over the area 
overnight set the stage for stratus and/or fog. Confidence is 
fairly low on which it will be, especially for north central 
Illinois. This is the area that has a slightly better potential to
clear toward sunset and the area that is being hit hardest by 
high-resolution guidance for potential dense fog. Have areas of 
fog mentioned into the morning for this region. Feel that the 
eastern half of the CWA including Chicago, which has had less 
shower coverage and currently under more close-celled clouds, is 
likely to stratify more so than fog in.