May 12, 2000
Storm Chase
This
year's storm season in Ontario really started off with a bang. Since
5 May, southern Ontario has been under the gun for active thunderstorms.
On 5 May, a tornado rated as F0 touched down in Madoc, a town in eastern
Ontario. This tornado caused tree damage and it destroyed parts of a
rural home's roof. Dave Sills was on this particular storm at the time.
He said there was lots of hail and the storm even had a "beaver's
tail" going off into the core. Little did we know what would be
in store for us folks in southern Ontario for the next few days. On
7 May, more severe thunderstorms roared in eastern Ontario. On the 8th
and 9th, severe weather occurred in southern Ontario. Squall lines and
supercells wrecked havoc across the region. Since the 7th, I decided
to have a look at the 36 hr Eta sounding for station CYKF (Waterloo).
Lo and behold, the indices were favorable for severe thunderstorm development
on the 9th. CAPE was forecasted to be 1434 J/kg, while LI's were -4.2.
This showed me that the atmosphere would be unstable. The RH was said
to be 84%, while the Td was 20.2 deg C. Temps were quite hot too, thanks
to a Bermuda high. 28.9 deg C was forecasted. The Eta then showed that
there was a 80% chance of thunderstorms. I decided to watch this developing
situation, since severe weather broke out in the US Plains and Midwest.
Those storms were expected to track NE into the Great Lakes region.
According to the SPC's day 2 outlook, we were under a moderate risk.
However, one thing did hold me back from chasing these storms on the
9th... they arrived in Waterloo at 11 PM EST. Very strong wind gusts
in excess of 100 km/h were reported in some areas in the SW, which caused
tree damage and power outages. I didn't go chasing, but at least my
forecast was right. In fact, the storm was more severe than I had thought
it would be... tornado warnings had been issued.
Finally, 10 May
gave us a break from Mother Nature's wrath, but on the 11th, southwestern
and central Ontario were once again under the gun. What? More severe
weather? Give us a break, Mother Nature! More severe thunderstorms happened
in SW Ontario... this time, just in Essex county. But on May 12th, we
would get hit once again with very active weather. And the season was
just beginning.
On the evening of
the 11th, I decided to run some Eta soundings to see if severe weather
was favorable. Severe weather was possible in the SW in the evening
of the 12th, according to Environment Canada's Convective Weather Statement.
I really wanted to chase this one, so I ran a sounding for CYXU (London).
WOW! CAPES were forecasted to be 1735 J/kg and LI's were -4.9. Hmmm,
it looks like another unstable day, I thought. Temps were forecasted
to be 30 deg C as well. I then made London my target. I had a difficult
time trying to find a promising sounding for CYKF. Also, SPC gave us
a slight risk. However, little did I know that things would change.
On the morning of
the 12th, a thunderstorm had woke me up at around 6 am. Lightning was
fairly frequent. It was pretty relaxing as well. But then around 9:30
am or so, things started to get a little more active. I was on the internet
retrieving data for the storms that were expected later on. But the
first sound of thunder and a darkening sky made me get off and turn
off the computer. I went out on the porch, when it really hit. Heavy
rain came down. A few minutes later, the rain started to get mixed with
pea sized hail. Then, that small hail started to get larger. Some stones
were fairly large, which I haven't seen in quite a while. I picked up
a few stones and put them in the freezer. This storm had to be severe,
I thought aloud. Sure enough, we were under a warning at 9:58. I knew
most of the hail would be 1 cm, so I made a report to The Weather Network's
storm line. I thought of calling a report into CANWARN, but I realized
the hail had to be 2 cm or more. My mom was coming home when the storm
hit. She saw an eerie green sky... the kind she had not seen in a long
time. Later that afternoon, I measured the hail. Some of the stones
were 2 cm big. And that was after they had melted slightly. Rats, I
should have phoned that into CANWARN! At least Dave Sills was kind enough
to enter my observation into Environment Canada's storm reports. One
inch hail was reported in Guelph that morning.
Like the usual,
I went to school and came back home. The first thing I did when I got
home was get some more data and any information from other chasers and
meteorologists. Now, my target had changed. Radar showed some real active
weather moving into Michigan. Supercells were popping up just about
everywhere, and it looked like this system was a MSC (mesoscale convective
system). These storms were responsible for over 20 tornadoes that raged
from Texas to Iowa. According to the Vortex100 Storm Chase Page's severe
weather discussion written by Meteorologist Robert Lattery , we were
in for something real active.
Exceptionally unstable
air is in place ahead of a cold front stretching from the Great Lakes
into the southern plains, with dew points in the 70's as far north as
Michigan and lifted indices forecasted to be in the -4 to -11 range
by this evening. Moderately strong capping will inhibit convection until
sunset from the mid-Mississippi valley into the southern plains, but
excellent surface convergence and very good upper level energy will
spark scattered severe thunderstorms from Michigan into northeastern
Texas during the evening hours as the cap weakens. A good combination
of high CAPE and shear values will enhance convective development, with
squall line and isolated tornadic supercell development likely.
Later that afternoon,
I called Dave Szozda, my uncle. A severe thunderstorm was issued for
much of southern Ontario, and him and I were planning on a chase. He
was not sure if we would see severe weather in the evening or not, since
the cold front was expected to arrive later at night. However, I saw
that convection was firing up ahead of the front. I knew we were going
chasing, so I grabbed my chase gear. Near dinner time, Dave Sills posted
to the wx-chase-can mailing list that he wanted to go chasing, but he
had no partner (he would feel insecure if he were by himself). So I
volunteered to take him along with us. He called me about this situation
and we discussed our target. We were going to head into Huron and Perth
counties. Radar showed a large tornadic HP supercell moving east off
of the coast of northern lower Michigan moving into Lake Huron. This
one was massive, and a tornado was spotted by a trained spotter 6 miles
west of Algers at 4:35 PM. Radar showed a TVS with this storm. I had
a strong feeling we were in for something big later. After I got off
the phone with Dave Sills, I ate dinner quickly and got ready for the
chase. Just then, a severe thunderstorm warning was issued for our target
area. After dinner, I waited for Dave Sills to arrive. The sun, which
was once shining, was now covered by cloud. At 6:15 PM, he arrived from
Guelph. He loaded his gear into my uncle's van (a.k.a. the Storm Descender),
and we took off at 6:20. My younger sister, Rita, also came along with
the three of us. Our first chase of the year had finally begun.
On the road, taking
highway 86 north, Dave Sills informed us of the lake breeze boundary
that had developed in our target area. If the storm, he said, reach
this boundary, it could blow up and produce a tornado. Lake breeze convergence
boundaries play a very important roll in the nature of our severe storms.
However, there is little known about how they do so. I showed him the
radar image I had printed off shortly before we left. On the storm we
were going to chase, there was a TVS. It was associated with the tornado
which was spotted in Michigan. This storm also had echo tops of 60 000
feet. The sky was overcast, and I really did not fussy it. An overcast
sky means that it would be harder for us to spot exactly where the storm
is. But then again, it was just the anvil from the large tornadic HP
supercell that we would soon encounter. I asked Dave Sills how high
the CAPES were currently. "4000 to 5000 in this area", he
said pointing to an area on the map, over Michigan. Wow. Enough said.
We had to intercept this thing.
When we pulled onto
county road 10, off of county road 86, it had started to drizzle. We
were going to intercept the storm from the south. The sky then started
to get darker as we continued to drive past Moorefield. Our target was
Mount Forest. From there, we would decide on where to go. Uncle Dave
gave Dave Patrick a call on his cell phone. According to Dave Patrick
(yes there are 3 Dave's; isn't that confusing?), 3 more storms had developed.
These were not mature yet, but he said it looked like they would go
severe. Great. Now which storm are we on? There were now 4. The one
huge HP supercell, plus the 3 other small ones. Dave Patrick's target
was Hanover. As we neared Mount Forest on county road 6, we noticed
that the sky was beginning to get black. Oh oh. This had to be that
HP supercell we saw on radar earlier. There were very little cloud features.
In fact, the clouds had NO detail at all. We pulled into a parking lot
at Mount Forest. Dave Sills took out his compass, and I took out my
wind measuring instrument (not an anemometer, but those white plastic
things). We were still in the inflow region, since the wind was blowing
to the west. I took some videos of an interesting cloud feature. The
rain started to get a little heavier, and the lightning was getting
more intense. Both of us got into the van and we continued our journey.
We had a hard time trying to get a good reception for the scanner, since
the weather radio would not come in clear.
As we drove more
NW of Mount Forest in Grey county, we noticed that the western sky was
getting very black. And this was at around 7:30. By now, it should still
be sunny, or the clouds should be lighter, since the sun was setting
in the west. But there were no signs of the sun at all. Night seemed
to move in pretty quick. And lightning was spitting out with such intensity...
CG's, crawlers, inner cloud, CC's, spider... you name it. The storm
displayed such an incredible light show... the kind I have never seen
in my years of storm watching.
As we were watching
the lightning, we pulled off of the road, the dark heavy sky continued
to come toward us. We were close to Hanover. At 7:50 PM, we realized
we were in deep "do do". It turns out, the core was headed
straight for us. Oh great move, I thought. The rain and hail swallowed
us. The wind whipped about with such a wild force that left us scared
inside the van. The rain came down horizontally. By now, we could feel
our adrenaline flowing. I wanted to head south, however, we could barely
see the road one meter in front of us. The heavy deluge was so bad,
the only real thought I had was oh shit. We had to get out of here,
but the extreme torrential downpour only made it harder... we could
not go anywhere. Uncle Dave was starting to get real worried. It was
only 8 PM, but by now, the sky was so black, like late evening after
the sun had set. Now I realized that chasing an HP storm isn't so hot
after all. It was impossible to take lightning pictures because of the
heavy rain which would only blur the image, and the windshield was covered,
even with the window wipers going at its fastest. This was an intense
half hour.
Finally, things had started to clear up... we were able to
drive again. We then started to look out for any signs of tornadic activity
as we headed south. Whew. There was none. As we drove eastward, we saw
a rural home. One of its hydro lines were torn down. We then arrived
back onto county road 6. We pulled off the road and got out of the van.
CG's were spitting out everywhere, and the scud cloud, or arcus, was
blowing pretty fast. Dave Sills pointed to a spot in the sky, just beside
the core. He said it was possibly a very weak meso since we could see
a slight curve in the cloud. I took a few pictures. As we got back into
the van, a crawler circled the sky above us and the thunder cracked.
I have never seen such intense and frequent lightning. Throughout the
whole chase, lightning of almost every kind flashed every few seconds.
By around 9 PM,
it started to get dark, so we decided to go back home. On the way into
Mount Forest, we saw that several trees were damage... limbs large and
small were lying on the curb. We pulled into a gas station for a snack
and to refill up on some gas. Surprisingly, this gas was pretty cheap
compared to the gas in Waterloo and Kitchener. We each bought some cookies
and a Snapple drink and sat there discussing our trip.
On our way home,
we encountered another storm. This one was not as intense, but it still
displayed an incredible light show. It was very dark out. Now I see
why chasing at night can be dangerous... you cannot see anything! We
arrived on highway 86. We then realized that the road was real dry...
it looked like the storm had passed to the north of Waterloo and Wellington
counties. We got back home at 9:30 PM. We took 1.5 hrs of video. Severe
storms continued to rage throughout the night across southern Ontario.
I took a few lightning pictures of the storm which arrived in Waterloo
at midnight.
The next day, I
got word that a gust of wind in Mount Forest reached 123 km/h at 8 PM.
The city also had reports of 92 mm of rain. A possible tornado in Niagara-on-the-Lake
was also spotted. A TVS was on radar at the time of the tornado warning.
But what I find intriguing is that there was a tornado warning out for
Huron county, which we did not recall hearing on the scanner during
the chase. It was issued at 8:49. Toronto also had reports of damage
from flooding and high winds. And earlier on the 13th, a flood warning
was issued for areas along the Grand River. Dave Patrick said some stores
in Elora were under 3 feet of water because of the severe storms overnight.
All in all, I would
have to say that this was my scariest chase. We sure have learned a
lot from this one. Also, it was a joy to have Dave Sills come along
with us. He has quite a bit of experience and knowledge that helped
us with our chase. Dave Szozda had concluded that he buy a laptop, that
way our chases would be easier. Now that I have the experience, I would
have to note that you do not want to be in a HP supercell's core*. We
were very fortunate. And if others wind up in the core, they might not
be so lucky. Chasing high precipitation storms could only spell one
word... danger.
Notes: Please note
that we did not intentionally wanted to be in the core. I personally
wanted to head south and miss it, thus being in the core was the very
last thing on my mind. "Core punching" is NOT a recommended
storm chasing practice!
Total hours: 3 hours
10 minutes
Distance: 181 km
