Jay Antle and John Moser's April 15 Chase Report (from WX-CHASE archive)

Date:         Sun, 26 Apr 1998 23:34:27 EDT
Reply-To:     Astrosfan1 
Sender:       The WX-CHASE list 
From:         Astrosfan1 
Subject:      4/15 Red Bud IL Chase Report-At Long Last...

     The morning of April 15, 1998 saw my chase partner (John Moser) and I
headed toward St. Louis on I-70.  Our initial target area was a St.
Louis/Carbondale Il./Mt. Vernon Il. triangle.  This was much further than we
were used to trying on an one day chase.  However, the dynamics looked
fantastic with EHI's forecasted close to 8 with helicities over 500 and CAPES
near 3000.  Further, unlike further west on the Plains the entire season thus
far, moisture was not going to be a problem here with dewpoints forecast well
into the 60s.  As a result, the SPC popped out a high risk for SE MO and S
Illinois.  So, John got off of work and I brought along my lecture prep
materials to read in the car (managing to stave off carsickness) and we headed
east.  We both brought along our 80s New Wave compilation CDS so this chase
had a definite throwback feel to it.
     Near Columbia MO at 11 am we registered 70 degree temps and 60 degree
dewpoints which boded well as we kept going towards St. Louis.  By this point,
we were already in the moderate risk zone as per the SPC.  We guessed that a
tornado watch would likely be issued for the St. Louis area by the time we
arrived there (not exactly a bold prediction).  We drove through broken
cloudiness from Columbia to near St. Louis which caused us to worry about
surface heating.  However, near St. Louis (about 1:20 PM) the clouds gave way
to VERY hazy sunshine.  The visibility would be poor but at least we would
have good surface heating.  By 1:40 we were in a PDS Tornado Watch stretching
south and west from our location at St. Louis.  Radio reports also suggested
that convection was beginning to go up in south central Missouri (near the
Lake of the Ozarks).  We considered cutting south on I-44 towards Rolla (and
even drove down it a few miles) but were faced with UNFRIENDLY chase territory
(read OZARKS) and I knew chasing in Southern Missouri was impossible for that
reason.  So we would have to wait until this stuff crossed into more friendly
terrain in Illinois.  But where to cross the Mississippi River?  Once you get
south of St. Louis, you have to travel almost fifty miles south to Chester in
order to find the next bridge across the Mississippi.  We decided (given what
we were hearing about where the convection was building) to head south on I-55
and cross at Chester.
     By 3:30 we stopped at a rest stop on I-55 about twenty miles NW of
Chester and got data from Chris King and Mike Phelps who were both monitoring
things for us (Thanks Guys).  Given how terrible the visibility was-despite
sunshine, their help was invaluable.  A supercell was coming out of central
Missouri.  We could also see a line of low cumulus with a few congestus mixed
in extending east to west.  This was the infamous outflow boundary along which
convection was to fire during the afternoon according to forecasts.  Dewpoints
on the south side of this boundary jumped from 62 to 68.  We decided to head
further north and cross the Mississippi at St. Louis (Poor tactics-In
retrospect we should have crossed at Chester according to original plan and
come up at the target cell from the south) and then make any northerly or
southerly adjustments on the Illinois side.  We were also hoping that other
convection might go up along the outflow boundary we had just left to our
south.  We assumed that this supercell would still have a slight northerly
component to its movement.  As it turned out, it moved more east than north as
it crossed the state.  By this point, on a non-hazy day we should have been
able to see the anvil of our target supercell...but not with the poor
visibility on this day.
     By 4:10 we began to see to our west nice anvil mammatus and the skies
darkened quickly as we booked north on I-55 trying to cross the river at St.
Louis and then get south on the Illinois side.  By 4:30 we crossed into
Illinois and a tornado was reported on the ground near St. Clair Missouri
moving in our direction.  By now, inflow bands were clearly visible feeding
into the dark skies to our west as we crossed the Mississippi.  At this point,
poor maps betrayed us.  Our strategy was to get drive through the town of New
Hanover and end up at Valmeyer.  Illinois is one of the few states in chase
country that neither one of us had good maps of.  To make a long story short,
we were about three miles further north than we thought.  Further, the storm
had no real northerly movement to it.  Along the way we warned a jogger about
the reported tornado on the ground on the other side of the river.  We were
now in the flood plain of the Mississippi staring up at a supercell bearing
down on us and we were too far NORTH (we just didn't know it yet).  By 4:48 we
were sitting on top of a flood levee near a several good escape routes and
were congratulating ourselves for our good placement as we had great views
across the river and into Missouri.  At this point, we discovered we were in
trouble.  By 5 PM, NWS suggested that the possible tornado would cross into
the Festus area by 5:30 so we began to head south on county roads (which our
map did not handle particularly well).  Inflow into the storm was clearly
obvious by watching flags and trees as we drove south.  Great inflow bands
were visible with lots of lightning to the west with the obligatory green
skies.  Clearly, this cell qualified as a BEAST!!!
     By 5:15 the precip core was on us....marble to dime-sized hail pelted our
car and we decided to head NE towards Waterloo on roads that were actually ON
our poor map.  Looking back at this, it seems clear that what happened is that
the storm back built and the meso which caused the tornado near St Clair began
to weaken while a second meso formed further south and crossed the river near
Festus.  In any case, we were on the north side of the precip core and
maturing meso.  So much for our self-congratulation about good
placement..sigh.  At Waterloo we decided to head south and east on hiway 154.
NWS reported a possible tornado 7 miles west of Crystal City MO. (On the west
bank of the River near Festus) at 5:15.  We decided to nudge the core between
us at Waterloo and the likely track of the possible tornado near Red Bud.  A
true core punch in this situation was out of the question.  By this point,
tornado warnings were out for Monroe and Northern Randolph counties.  (We were
in Monroe County..Red Bud was in Randolph County).
     By nudging the core, we encountered no worse than marble sized hail (we
managed to avoid the reported baseball sized hail with this storm).  We let
the worst of the hail pass to the east and then crawled south and east on
hiway 154.  As we got south of Waterloo, (roughly 5:40 or so) we heard the
tornado sirens go off.  Along the way, I discovered a new chasing resource.
We passed a bar with an open door and a satellite dish (PKG liquors..thanks).
We stopped, I ran in and got some quick radar data from the local TV mets who
were on air covering the situation.  Everyone was tossing down a brew
apparently underwhelmed by the whole event.  The big tornado on my T-shirt
(Thank you, Matt Biddle) started the usual round of "TWISTER" questions but we
were in a bit of a hurry.
     Just north of Red Bud, we broke out of the core.  The ground was covered
with hail which gave off a great deal of fog which reduced visibility for
about half a mile to near zero.  Looking to our east we could see the core and
a possible lowering but poor contrast hampered further ID.  At about 6 PM,
however, just to our WEST, there was a large scuddy lowering which almost
reached the ground and showed some signs of rotation.  Further, the hail fog
was blowing INTO it.  We accelerated quickly to get out of its way.  Frankly,
I'm still not sure what to call this thing.  Surface winds were not that
strong near it and the rotation was fairly weak as well.  We watched it
meander off to the NE and weaken.  At about this time, John Farley was south
of Red Bud and reported several large lowerings in his chase account for the
     At the same time (roughly 6PM) a tornado was reported by spotters 2 miles
west of Red Bud (perhaps our lowering?).  We stopped to look at the situation
again two miles NW of Red Bud on 154 and talked to a local who said he hadn't
seen a tornado yet although he had been looking.  As we drove through Red Bud
the sirens were going off there as well.  Once when we pulled over to the side
of the road south of town we were met by the local emergency management
coordinator who was out spotting and confirmed to us that one of his spotters
had reported a tornado.  By this point, roughly 6:15  We also unfortunately
picked up two vehicles of locals who were looking for "TORNADERS" who followed
us for almost twenty minutes.  One kid bragged about how he had driven
straight through all that hail in his tough truck.  Sigh..
     We decided to leave this cell and pursue interesting lowerings going up
on a cell near Ruma to the south of Red Bud on hiway 3 (ever in search of
tail-end charlie)  After watching these lowerings (which never did do that
much from our vantage point for about half an hour) we headed back north to
Red Bud and stopped at the local Hardees for a break before we headed back
home ( a LONG drive home ahead of us).  We knew there were severe warnings up
for Monroe county on a new storm just to our north but we didn't expect much
from an already worked-over atmosphere.  In Hardees we talked to locals about
the storms (one kid reported seeing a funnel cloud) and answered the usual
TWISTER questions.  At this point, the Hardee's effect took over.  John and I
have gone into Hardee's burger joints (which have lousy food) and come out to
find convective nirvana.  Well, it happened again.  This was 7:10.  We came
out of Hardees, looked up and our jaws dropped.  Right above us was a
extraordinary, tiered, shelf cloud which extended to the north and east.  We
turned on the weather radio and a tornado warning was out for Monroe County
(sirens were going off in Waterloo..again).  By now, it was getting close to
dark but we headed north to see what we could see.  Once we crossed the shelf
cloud, the winds really didn't do that much.  (Stopped at another bar for a
quick look at radar..these stops take no more than 40 seconds and are very
helpful-a drunk guy at the table looked up over his mug to slur "just go north
about forthy miles or so...") By this point, tornado warnings were going out
all over the place to the north and east of us.  By 7:20, as we were just
south of Waterloo, we could barely make out a sloping feature half hidden by
rain curtains off to our NE.  This could have been the wall cloud from the
tornadic storm moving out of Monroe County.
     By this point, is was getting dark and we called it a day.   We arrived
back home at roughly 1AM.  A 15 hour chase day...  All told, it was well worth
the drive especially given how poor the season has been on the Plains.  Sorry
for how long it took to get this chase report out.  Happy Hunting All!

Jay Antle

John Moser