June 23, 2010 – Northern Indiana Derecho

I was anticipating some pretty decent severe weather across central Lower Michigan.  This did not pan out at all.  I ended up heading just across the border into Indiana to at least catch the derecho that was heading east so the day wouldn’t be a complete loss.  I sat around home in Grass Lake, MI until about 1pm before I decided to go out.  Although the SPC had trimmed back the moderate risk to exclude most of mid-Michigan, the ingredients still looked pretty good.  The worrisome thing was the cloud shield left over from the MCS that cruised through in the early morning around 10am.  However, there was some clearing in Wisconsin and across Lake Michigan, so hopefully that’d propagate into Michigan.  I had figured everything in Illinois and Indiana would go linear and develop into a derecho as the day progressed and I figured central Michigan was the best chance for isolated storms.

So I left home and headed towards Grand Rapids.  Once I turned west onto I-96 the clearing really started to take over.  The sun came out, temperatures were back in the low 80s after that early morning MCS.  What I wasn’t aware of, at the time, is the atmosphere had begun to mix out.  The dewpoints were actually dropping, and while mid 60s is respectable, it was drier air than was there a few hours earlier: it was low 70s around 11am.  CAPE, although it had built up until this time to 1,000 not only began to erode, but a cap started to settle in.  21Z rolls around and mesoanalysis indicates CAPE is all but gone around Grand Rapids, a 100 J/Kg cap has set in.   All around me was blue sky.  Decided to head south, back towards Lansing, grab some dinner and figure out what I wanted to do.

While stopped for a bite to eat, perused the satellite and mesoanalysis and decided nothing was going to fire up here.  Decided my only chance to see any weather was to high tail it down to the Michigan/Indiana border to maybe have a play on the derecho as it approached.  I got back on I-94 around 23Z and headed west.  Storms started to popup along the highway corridor along the warm front.  They would later progress eastward where they caused a tornado warning back home and a tornado  over by Milan.  I continued on to intercept the derecho and attendant cold front in southwest Michigan/Northern Indiana.

I beat the derecho to US-31 and jumped on that highway to head south into Indiana.  There were plenty of SLC associated with the shelf cloud out in front of the storm.  The line was packing some intense winds…here is a Severe Thunderstorm Watch issued at 8:28PM out of Northern Indiana:

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE NORTHERN INDIANA
828 PM EDT WED JUN 23 2010

THE NATIONAL WEATHER SERVICE IN NORTHERN INDIANA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
CASS COUNTY IN SOUTHWEST MICHIGAN...
ST. JOSEPH COUNTY IN SOUTHWEST MICHIGAN...
NORTHWESTERN KOSCIUSKO COUNTY IN NORTH CENTRAL INDIANA...
MARSHALL COUNTY IN NORTH CENTRAL INDIANA...
WESTERN LAGRANGE COUNTY IN NORTHEAST INDIANA...
SOUTHEASTERN ST. JOSEPH COUNTY IN NORTH CENTRAL INDIANA...
ELKHART COUNTY IN NORTH CENTRAL INDIANA...
EASTERN STARKE COUNTY IN NORTHWEST INDIANA...

* UNTIL 930 PM EDT/830 PM CDT/

* AT 824 PM EDT/724 PM CDT/...NATIONAL WEATHER SERVICE DOPPLER RADAR
INDICATED A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING
EXTREME DAMAGING WINDS IN EXCESS OF 90 MPH. THESE SEVERE STORMS
WERE LOCATED ALONG A LINE EXTENDING FROM 10 MILES WEST OF DOWAGIAC
TO 7 MILES NORTHWEST OF NORTH LIBERTY TO 11 MILES WEST OF KNOX...
AND MOVING EAST AT 55 MPH.

It is very rare to see them with wording as strong as that one, but they weren’t joking around, the winds were extremely serious in this storm.  I hopped on the toll road to bolt east and stay ahead of it.  I got off at Howe to head back up into Michigan.  The storm caught up to me just east of Sturgis.  I saw Ben Holcomb put a report up on SN about a 79 mph wind gust.  He was a few miles south of me at that point.  I got into some heavy wind, but I don’t think anything hit over 70 mph.  Anyway, I spent the rest of the trip home driving in rain and wind and dodging road debris for the next few hours.  Unfortunately I didn’t get any good pics or video of this event as it was dark, but man I have plenty of video of blue skies!

Storm Reports

• NWS DTX – 2 tornadoes confirmed
• NWS GRR – 1 tornado confirmed
• NWS IWX – 7 tornadoes confirmed; 2 100mph microbursts
• NWS LOT – 1 tornado confirmed

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