April 10, 2008

Statistics:

Initial Target: East of Hannibal, MO
Departure: University Park, IL 2:45 pm
Arrival: Bolingbrook, IL 12:15 am
Intercepts: New Salem, IL
Tornadoes: 0
Hail: None
Wind: Non-Severe (not measured)
Features: RFB
Miles: 519

Summary:

Very powerful extratropical cyclone was moving up the plains, bringing a warm front up through the Midwest and marginal instability behind it.  Targeted west central IL, not wanting to chase MO, and left with Chad Cowan after work.  Line went up in Missouri while enroute and targetted tail end and new development to south, while northern end went Tornado warned.  New development evaporated as it crossed the MS river, but provided some photo ops.  Warned cells to north also start to fizzle and raced at uncatchable speeds.  Called it a chase at 7pm, catching dinner with Andrew Pritchard in Havana, IL.

Crew and Equipment:

Chase partner: Chad Cowan.  Equipment: TH-F6A Tribander, and GPS/Cell Phone equipped laptop.  Photography by Skip Talbot.

Details:

After six months, and a long, snowy winter, I was finally back on the road.  The day before this setup looked like it could go high risk with a sub 990 surface low, 100+ knot midlevel jet, and 80 knot low level jet, the shear was extreme.  The problem with this early season setup, of course, was the instability.  A meager 1000 J/Kg was expected into MO behind the warm front.
Just as our chase opportunities had been spoiled two days earlier by morning junk convection, this morning was socked in with a mess of rain and clouds that were not clearing.  By noon the chase prospects looked pretty bleak, however, Chad was on his way to meet me at the Metra stop near my work so, after a quick data check, we left anyway.  I had to work a full eight hours and so we were delayed until 2:30 before leaving, but at that time not much was going on yet.
We headed south on 55 to 72 making for the western edge of Illinois.  Grey overcast and misting skies were all we saw until we got to Jacksonville.  Then, as if a symbol of winter's end and the start of a new chase season, the cloud deck abruptly ended with blue skies behind it and the sharp edges of building storms.
As we made it to our target area, a line went up in eastern MO, and was moving northeast at speeds greater than 50 mph.  We hoped to catch Tail End Charlie, but the storms slipped north of Quincy.  Looking northwest at the short, yet backsheared end of the storm towers.
The northern end of the line went tornado warned, and Brandon Sullivan, Illinois chaser from Macomb was in the right place at the right time and bagged it as it passed quite close to his location.  Chad and I sat off of 72 just past Griggsville, waiting for some more isolated to cells to cross the Mississippi and becmoe mature.  The raging low level jet, whipped some clouds past us as a scene sunset started.
Something was missing from the magical mix of storm ingredients, and our discrete cells never matured, but instead started to evaporate right before our eyes.  Despite its pendent shape and radar echo showing an oddly curling back end that resembled a hook echo, the storm passed us as little more than a shower.  We were still able to note a distinct precipitation core, rain free base, and upward moving scud.  A brief funnel look a like as the storm passed:
Artsy shot looking west as the tiny storm passed over a farm:
The storm we were watching and the other around continued to evaporate, as either they crossed into an area of lesser instability, dropping moisture, a strengthening inversion, or perhaps a combination of these.  The line to our north, which still held some severe warnings, was moving too fast to even consider catching up to it.  We started heading north towards Mount Sterling, to keep up with our dieing little cell, but even had trouble doing that.
We stopped from some grub and met up with Andrew Pritchard at a little diner in Havana.  He got out there a little earlier and intercepted the tail end of the line that we could only watch scoot past to the north.  I finished the drive home with Chad, making it back to Bolingbrook just after midnight.  A fun first outing for the season, despite the bust.
Conclusion:

The first chase of the year was a heavily hyped setup, where the highest tornado probabilities wound up busting completely, and the lesser areas of Iowa  wound up producing quite a few tornadoes.  We might have been able to get some better storm structure had we been able to leave earlier and make it to the target area before the line in eastern Missouri went up, however, with storms speeds and lack of storm longevity, chasing this day required a good deal of luck in order to bag something significant.  Feeling seventy degree temperatures with strong southeast winds, and snapping a few pretty pictures definitely made the outing worth it, however.

Other Chaser Logs:

 

Lessons Learned:

  • Don't discount less anticipated areas of the tornado outlook.
  • Busts with scenic pictures are still enjoyable.