July 19-20 Severe Weather

[Memphis Weather]

 

[hlcater]

(super long post) Well. Uh... I scored. I started the day near Newton IA, what was interesting was as soon as the first storm went off, it immediately went tornado warned(within minutes of 50dbz). I found this surprising and as it turned out, would set the tone for the day. My first tornado came near Colfax probably 30 minutes after the initial warning and was the 2nd(3rd) tornado that storm produced. I caught it from a distance with some good contrast.



As this tornado roped out, the storm wasted no time cycling and soon dropping another tornado immediately south of Prairie City. This was my favorite due to the lack of damage caused and good viewing angle. 



and a video of the same tornado

 

Again the storm wasted no time and was wrapping up before this tornado was done. I didn't get any good pictures of the 3rd tornado as I was driving at the time. Short live stovepipe near Monroe.

The next two tornadoes featured a little more staying power than the last two. Both being strong looking cones near Pella, IA. One to the NW and another in Pella and to the SE. I got a pretty nice angle on the RFD, with the rain wrapped cone for tornado number 4. The RFD on this storm was particularly dramatic at times and something more characteristic of the High Plains than of Iowa. Normally this area is super HP and filled with rain. While under that cut, I could see deep into the storm's updraft.

After passing through Pella, I came out on the other side and was immediately greeted by a very welcoming tornado number 5. This was the tornado that destroyed the manufacturing plant in Pella. I was perfectly positioned smack dab in the middle of the RFD for the entire duration of tornadoes  5 and 6. There wasn't much hail(topping out at nickle size), and the rain really wasn't too bad for Iowa standards either, but the wind was exceptional at times measuring at least 80-90mph. Tornado number 6 was a brief satellite this tornado, of which I didn't get any pictures. This would be the end of my chase as my car had decided it was fed up with the RFD and the red battery light came on. As such, I called the chase there and headed back early, with no further issue. However it doesn't appear I missed any more tornadoes.


 

All in all, absolutely stellar chase with all different types of structure and tornadoes and easily the best chase I've had.(Although my chase portfolio is still quite small.)

[yoda]

8 confirmed fatalities now... reports of people still missing

https://mobile.twitter.com/EthanForhetzTV/status/1020140588501553152

1 hour ago, Memphis Weather said:

 

 

[snowlover2]

Wow hlcater great job and great pics.

[bdgwx]

Here is video taken from what I believe is the Showboat Branson Belle. That is a larger vessel than can weather the storm. The two boats is the video are Ride the Ducks vessels. One of them sinks. The video cuts out just before it goes under. Fair warning...this is devastating to watch.

http://www.ky3.com/content/news/CAUGHT-ON-CAMERA-Viewer-captures-Ride-the-Ducks--488687431.html

[Stebo]

26 minutes ago, bdgwx said:

Here is video taken from what I believe is the Showboat Branson Belle. That is a larger vessel than can weather the storm. The two boats is the video are Ride the Ducks vessels. One of them sinks. The video cuts out just before it goes under. Fair warning...this is devastating to watch.

http://www.ky3.com/content/news/CAUGHT-ON-CAMERA-Viewer-captures-Ride-the-Ducks--488687431.html

That's so tough to watch...

[SchaumburgStormer]

31 minutes ago, bdgwx said:

Here is video taken from what I believe is the Showboat Branson Belle. That is a larger vessel than can weather the storm. The two boats is the video are Ride the Ducks vessels. One of them sinks. The video cuts out just before it goes under. Fair warning...this is devastating to watch.

http://www.ky3.com/content/news/CAUGHT-ON-CAMERA-Viewer-captures-Ride-the-Ducks--488687431.html

Absolutely brutal. Tough to watch, and I can only imagine those on the large Belle who watched this in real time unable to assist. 

Sherrif confirming 11 fatalities with 5 unaccounted for. 

http://www.ky3.com/content/news/Emergency-crews-work-incident-involving-amphibious-boat-on-Table-Rock-Lake-488679201.html

[Hoosier]

11 dead now with some people still unaccounted for.

I can't remember a non-tornado severe weather related death toll like this in a while.  There was that concert incident in Indy several years ago but that wasn't as deadly.

[Indystorm]

And my cousin and I have taken this Ride the Duck amphibious ride at Branson a couple years ago and have dined on the Showboat Belle,  Absolutely chilling video.

[Indystorm]

This brings to memory another tragedy in Kansas from years ago.  I knew someone who died in this incident from a relatively weak tornado.

The 1978 Whippoorwill tornado also known as the Whippoorwill Disaster was a tornado that struck on June 17, 1978. The tornado, which was on the ground for 8 miles (13 km), struck a tourist boat called the Whippoorwill, causing it to capsize and drowning sixteen out of the 58 passengers and crew.

1978 Whippoorwill tornado - Wikipedia

[snowlover2]

11 hours ago, andyhb said:

Could pretty easily see a moderate for wind tomorrow given the amount of instability blended with unseasonably strong deep layer shear. My question revolves around the extent of the veering with height in the lowest 6 km and whether that might curb some of the long-lived MCS potential (and possibly raise the tornado threat).

You called the moderate but its for hail.

Quote

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1234 AM CDT FRI JUL 20 2018  
 
VALID 201200Z - 211200Z  
 
...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS FROM WESTERN TN  
TO SOUTHERN IN...  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM LOWER MI TO  
MS AND AL...  
   
..SUMMARY  
 
SEVERE THUNDERSTORMS WILL DEVELOP ACROSS THE OHIO AND TENNESSEE  
VALLEY REGION INTO THE MID-SOUTH FRIDAY. VERY LARGE HAIL, DAMAGING  
WINDS, AND A FEW TORNADOES CAN BE EXPECTED. ISOLATED SEVERE STORMS  
ARE POSSIBLE ACROSS THE CENTRAL HIGH PLAINS.  
   
..OH/TN VALLEYS INTO THE MID-SOUTH  
 
STRONG MID-LEVEL JET, IN EXCESS OF 60KT AT 500MB, IS FORECAST TO DIG  
SOUTHEAST ACROSS THE MID-MS VALLEY REGION FRIDAY AS PRIMARY  
MID-LEVEL CIRCULATION SETTLES INTO THE SOUTHERN LAKE MI AREA DURING  
THE LATTER HALF OF THE PERIOD. WITH 500MB HIGH CENTERED OVER THE  
SOUTHERN HIGH PLAINS, PRONOUNCED MID-LEVEL DIFFLUENCE WILL EXTEND  
ACROSS A GOOD PORTION OF THE OH VALLEY INTO THE CENTRAL GULF STATES.  
THIS LARGE-SCALE REGIME WILL PROVE FAVORABLE FOR ROBUST CONVECTION  
ALONG THE EASTERN PLUME OF SOUTHERN PLAINS HEAT DOME.  
 
EARLY THIS MORNING A SUBSTANTIAL RESERVOIR OF INSTABILITY EXISTS  
FROM THE CENTRAL PLAINS INTO THE LOWER MS VALLEY. SEVERAL POCKETS OF  
STRONG/SEVERE THUNDERSTORMS HAVE EVOLVED WITHIN A WARM ADVECTION  
CORRIDOR ACROSS SOUTHERN KS/NORTHERN OK AND AHEAD OF THE LARGER  
TROUGH OVER WI/IL. THIS ACTIVITY IS NOT CURRENTLY EXPECTED TO GROW  
UPSCALE PRIOR TO DAYBREAK. AS A RESULT, EXTREME BUOYANCY IS EXPECTED  
TO DEVELOP ACROSS THE MID-SOUTH INTO SOUTHERN IN WITHIN  
SOUTHWESTERLY LOW-LEVEL FLOW WHERE SURFACE TEMPERATURES ARE EXPECTED  
TO WARM RAPIDLY AHEAD OF SYNOPTIC FRONT. THE AFOREMENTIONED  
MID-LEVEL JET WILL DIG INTO THIS REGION DURING THE DAY ENHANCING  
SHEAR PROFILES AND VENTING ALOFT FOR ROBUST UPDRAFTS.  
 
CURRENT THINKING IS STRONGER FORCED REGIONS OF IN/LOWER MI WILL  
EASILY CONVECT BY EARLY AFTERNOON AND A POSSIBLE SQUALL LINE COULD  
EVOLVE AFTER 18Z WHERE MID-LEVEL BACKING AND HEIGHT FALLS ARE MORE  
EVIDENT. HOWEVER, MORE INTENSE THUNDERSTORMS ARE EXPECTED TO DEVELOP  
TOWARD 21Z FARTHER SOUTH ACROSS WESTERN KY, THEN INTO WESTERN TN BY  
LATE AFTERNOON. FORECAST SOUNDINGS ACROSS THE MDT RISK REGION ARE  
QUITE IMPRESSIVE REGARDING BUOYANCY WITH SBCAPE ON THE ORDER OF  
5000-6000 J/KG AND SFC-6KM SHEAR APPROACHING 60KT. ENVIRONMENTAL  
PARAMETERS STRONGLY FAVOR SUPERCELLS ACROSS THIS REGION AND VERY  
LARGE HAIL COULD ACCOMPANY THIS ACTIVITY. IN ADDITION, TORNADO  
THREAT WILL BE GREATEST WITH THESE DISCRETE STORMS THAT WILL  
PROPAGATE STRONGLY SOUTHEAST AROUND 25KT. IF THIS REGION IS NOT  
CONVECTIVELY CONTAMINATED PRIOR TO MID AFTERNOON THERE IS SOME  
CONCERN THAT A HIGHER TORNADO THREAT MAY BE EMBEDDED IN THIS REGION.  
WILL MONITOR MESOSCALE DETAILS AND ADDRESS THIS CONCERN IN LATER  
OUTLOOKS. OTHERWISE, MULTIPLE SEVERE THUNDERSTORM CLUSTERS SHOULD  
EVOLVE ACROSS THE MID-SOUTH DURING THE EVENING WHICH SHOULD  
PROPAGATE ACROSS NORTHERN MS/AL WITH AN ATTENDANT THREAT FOR LARGE  
HAIL/DAMAGING WINDS.

 

[Stebo]

Quite the expansion of the risk area for tomorrow, if stuff can remain discrete closer to the low I would expect a better tornado potential, sort of like a poor man's version of yesterday.

[Stebo]

I do also thing they will be upgrading the areas to the south with respect for wind, 5000-6000 J/kg and 60kt of 0-6km shear screams explosive atmosphere, and if a MCS can form it will lay down some significant winds.

[Hoosier]

Looking at the categorical risk map... if I didn't know any better I would guess it was just about any other time of year besides the middle of summer. Impressive to see such a large north-south risk area. 

[Torchageddon]

2 minutes ago, Hoosier said:

Looking at the categorical risk map... if I didn't know any better I would guess it was just about any other time of year besides the middle of summer. Impressive to see such a large north-south risk area. 

That's exactly what I first noticed. Can't think of any categorical risk map looking like that in July or August.

It sucks to hear of the large loss of life in yesterday's severe weather.

[Stebo]

GRR's thoughts on today

Quote

Elevated showers and thunderstorms were rolling in from the
southwest to start the day. The latest HRRR seems to have a good
handle on the situation. It shows the convection generally
diminishing as it move in through the morning hours. The overall
severe and heavy rain risk looks low to start the day. That
changes this afternoon. Surface based CAPE values climb to over
1000 j/kg. That combined with back surface flow...some dry air in
the mid levels and stronger wind fields supports a risk for some
severe weather. Damaging wind and large hail appear to be the main
hazard. The some UD helicity swaths start to show up after 19z
primarily south of of a Muskegon to Lansing line...which could
support a tornado. The rainfall could be heavy with any of the
stronger cells. Locally an inch or two of rain looks possible
into tonight with any of the bands of storms.

 

[Stebo]

IWX

Quote

At least partial insolation expected prior with conditional svr risk (wind)
tied to degree of realized sfc based destabilization as effective
shear adequate to support organized convection. However better svr
prospects along with some tor risk seen further south into cntrl IN
where stronger mid level flow overlaps channel of backed sfc flow
and where greater sfc based instability should manifest.

 

[Stebo]

DTX

Quote

Today...Strengthening south southeasterly flow has allowed surface
moisture to return the past couple of hours with sfc dewpoints now
reaching 60 degrees. Midlevel moisture is still lacking at this
early hour, but plan view perspective shows rapid moisture return in
the 850-600mb layer by 15Z. Initial arc of accas and elevated
showers over far western Lower Michigan appears tied to 875mb
moisture. Not much else going in the near term and will keep the
forecast dry ahead of 12Z. Aforementioned deep midlevel theta e axis
arrives late morning and afternoon bringing increasing chances for
showers and thunderstorm development. Saturation of the 2.0 to 6.5
kft agl layer will allow SBCAPE/MLCAPE to increase particularity
during the late afternoon hours. Latest projections suggest that as
much as 1000 J/kg to potentially 1500 J/kg will be feasible. Cloud
cover may become a concern, however, quality of moisture lends some
confidence in the instability. What is really a question is amount
of shear that will exist this afternoon over Southeast Michigan. At
first glance, one notices integrity of backed southeasterly surface
flow, but little directional shear will exist in the midlevels which
significantly compromises hodograph length. 0-3km SRH is expected to
remain less than 100 m2/s2 for the majority of Southeast
Michigan with 0-6km bulk shear generally between 15-20 knots.

Attention will be on far Southwest Michigan 17-19Z timeframe as an
arc of thunderstorms are expected to initiate. Consensus of CAMS
show this thunderstorm activity struggling to lift northeastward
given mean flow, losing intensity west of the cwa between 22-01Z.
The severe thunderstorm threat for today largely appears tied to
this thunderstorm activity that will originate over SW Michigan.
Really a conundrum with how the dynamics are set up. Models show a
period of outstanding direct PV advection, however, system relative
isentropic ascent will be poor given unidirectional flow in the
lowest 10 kft agl. It remains possible that a favorable
shear/instability balance will be struck with some thunderstorm
activity bringing an isolated severe threat. Latest Swody1 has much
of Southeast Michigan in a Slight Risk designation. The most viable
threats being damaging wind gusts to 60 mph and large hail to 1 inch.

 

[CheeselandSkies]

Yesterday was the atmosphere's every few years reminder that Lieowa does have significant and photogenic tornado events, just not on the moderate risk/PDS days with off the charts STP values. That's when you get either instant upscale growth or a cap bust.

[buckeye]

5 hours ago, Hoosier said:

....

I can't remember a non-tornado severe weather related death toll like this in a while.  There was that concert incident in Indy several years ago but that wasn't as deadly.

Yea, especially because of wind. Flash flooding associated with a severe storm would be an exception.  For instance, 26 dead in Shadyside Ohio in July of 1990 from an isolated thunderstorm that produced a flash flood.

That duck boat video is gut stretching.

[geddyweather]

12z SPC draws the MDT north into the Cincinnati, Indy, and Dayton areas. Upgrade throughout the area in TOR probs: 10% in the MDT, 5% in the majority of the surrounding ENH.

[snowlover2]

28 minutes ago, geddyweather said:

12z SPC draws the MDT north into the Cincinnati, Indy, and Dayton areas. Upgrade throughout the area in TOR probs: 10% in the MDT, 5% in the majority of the surrounding ENH.

Moderate on my doorstep.

[yoda]

8 hours ago, Hoosier said:

11 dead now with some people still unaccounted for.

I can't remember a non-tornado severe weather related death toll like this in a while.  There was that concert incident in Indy several years ago but that wasn't as deadly.

Death toll is now at 13... with children among the dead.  Four people still missing 

https://www.yahoo.com/gma/8-dead-missouri-duck-boat-accident-025903630--abc-news-topstories.html

[HillsdaleMIWeather]

Anyone else worried about all the morning convection?

[OHweather]

I'm not too worried about destabilizing right along the warm front as far north as far southern MI, though it may stay stable not far onto the cool side of the boundary.  It looks like a narrow corridor along and just on the cool side of the warm front from central IN into far SW OH will have strong low-level shear and moderate to strong instability to work with, which may be the best bet for some initial supercells with large hail and a few tornadoes.  The parameter space, assuming we do destabilize, may again get up into an area that can start supporting a strong tornado with over 200 m2/s2 of SRH and plenty of MLCAPE...though with ample large-scale lift, have to think upscale growth will occur fairly quickly, and mainly W-E storm motion may take storms too far east of the boundary into more stable air relatively quickly, so the overall window for a better tornado threat may not be large.  A little farther north low-level turning remains strong along the warm front into northern IN and southern MI, though the upper-level flow is definitely weaker and instability may be a little more questionable (though I think ultimately still adequate for some risk to play out).   So stuff may be a little messier in northern IN/southern MI, but there's probably enough low-level shear and instability for some (perhaps less persistent) supercell structures with a hail and tornado risk (more marginal on each though). 

I'm sure the cold front farther SW across far southern IN/IL and into western KY will develop storms more than some CAMs show, as it will be uncapped with the left-exit quad of the jet streak moving overhead with extreme instability and strong deep-layer shear.  Low-level flow isn't as favorable for tornadoes along the cold front, though the deep-layer flow will support supercells with a very large hail risk.  Suspect the greater tornado risk would be along the warm front if that area pans out.  Upscale growth into clusters/MCSs with what appears to be a potentially significant wind damage risk may again occur fairly quickly as we head into the evening...wouldn't be surprised to see some increase in the wind risk from the SPC if short-term signs can point to good development along the cold front being likely (which I suspect it probably is).

[HillsdaleMIWeather]

Sun is actually trying it's damndest to come out here right now. Kinda surprised.

[OceanStWx]

5 hours ago, CheeselandSkies said:

Yesterday was the atmosphere's every few years reminder that Lieowa does have significant and photogenic tornado events, just not on the moderate risk/PDS days with off the charts STP values. That's when you get either instant upscale growth or a cap bust.

Well some of it is probably perception. Moderate+ days have nowhere to go but bust.

But those mixed signal, slight risk days can have some of the bigger outbreaks because there is often one ingredient “missing.” Usually capping or questions about heating, only takes a small break to turn things into a positive bust. 

[OceanStWx]

HRRR looking like two areas of concern: one along the warm front from MI into IN, then the other on the nose of the mid level jet sparking a MCS later in the day down around PAH. 

Also the HRRR updraft helicity seems to be busted and is not plotting.

[Jackstraw]

Still hazy here but dews are definitely on the uptick.  I'll be out running some errands around 2 so hopefully I can catch something along the warm front.  Radars around the area have been cool to watch with these little vortices spinning around the main low. 

http://weather.cod.edu/satrad/nexrad/index.php?type=ILX-N0Q-1-24

[Harry Perry]

Certainly a hard video to watch...  I can’t imagine what the captain was thinking much less the people and kids aboard. Can tell they were all trying their hardest to get to a safe zone. Will be keeping them in my thoughts and prayers. 

As for today’s risk... I’m growing increasingly concerned for southern lower MI/northern Indiana and Ohio - being in such close proximity of this warm front (that’s currently overhead) - even as this last bout of rain fell you could feel the wind shift and temps rise a few degrees. This morning elevated convection really packed a punch. Some limbs down and pea size hail in Kalamazoo, and prolific lightning and heavy rain in Battle Creek. I see the 14z HRRR is showing some real monsters (discrete sups) blowing up just south of the triple point and sweeping through. Feel like this is our day to watch in Michigan after having such a quiet spring and summer. Events like these can make a quick unexpected surprise fast. Will be interesting to see what transpires here later on today - even despite the mornings convection.

 

Edit: Already getting filtered sunshine here.