Line of Severe T’Storms Possible This EveningJune 18th, 2014 at 10:42 am by Chad Evans under Chad's WLFI Weather Blog
It is already hot, humid & very capped with cirrus shield across area from the tops of storms nearby. Cumulus are bubbling up in a line in our north along outflow boundary.
It is already 85.3 degrees with a dew point of 73 as of 11:17 p.m. at the station!
Two lines of storms lastnight to now have stayed just north of our area, but the first line has put out an outflow boundary in our far north.
Despite capping today, this may still pop a few storms, which could go severe if they can get entirely through the cap. Large hail/downburst/isolated brief tornado would exist with any of these isolated cells IF they can pop through.
Besides this, I think we really need to watch this evening. Thinking is that line of storms or a bow will form on the tail of storms currently over northern Illinois.
Thinking shortwave coming out of Iowa will be main trigger, which will weaken cap.
Given high surface CAPE of up to 4000 J/kg & the fact that we will be on the southern fringe of stronger flow & shear, a damaging wind event is looking more & more in the offing. Futurecast was on to it last night at 11 p.m. & new data is now hinting at it.
Given high CAPE, it is possible that perhaps some scattered large hail may accompany the line.
We will continue to monitor this.
Current analysis suggests a few more storms Thursday morning, then perhaps clusters Thursday evening & then Friday afternoon.
NAM has a complex of storms northwest of our area at 7 p.m. Saturday evening, but much of the day dry, hot & humid. Based on this, it would appear that this complex would pass Saturday evening-night.
Some storms are even possible Sunday.
In terms of severe weather, even though the main dynamics/stronger flow aloft/shear will tend to migrate back north Thursday-Sunday, surface CAPE of up to 4000 J/kg Thursday, Friday & 3000 J/kg Saturday, then 2500 J/kg Sunday would promote pulsey, vigorous convection.
Storms could consolidate into cluster & outflow boundary-generated cold pools from storms could locally-organize storms into lines. That said, at least isolated to scattered severe wind & hail threat will exist daily Thursday-Sunday.
Looks like the high CAPE will be shoved southwest & weak surface cold front will bring couple/few days of dry weather with lower humidity early next week with highs in the 80s & lows near & into the 60s.
Hotter more humid weather with upper 80s to perhaps 90 mid- to late-next week will usher in potential of storms.
After that, we might have 3-4 days of below-normal temperatures with highs in the 70s to around 80 & lows in the 50s with dry, pleasant weather.