2016-04-27 REPORTS: IA/KS/MO/IL

[cdcollura]

Good day all,

Starting thread for April 27 storm reports (here's mine)...



Above: LP storm developing near Shelby County, Missouri.



Above: Hail from LP supercell storm near Shelby County, Missouri south of Highway 36.



Above: Developing Tornado southwest of Emden, MO after dark (also in Shelby county and well north of Highway 36).




Above: Tornado nearing Emden, MO. Hearing cracking of trees, loud roar, and ears popping at this time!



Above: Tornado moving northeast (with debris) of Emden, MO, after I back away to safe distance to west. Sorry about the low light on these...

Chase Details For 4/27 Below:

On April 27, I woke up early (in Wichita, KS) and planned / forecasted for that days chase, which, fortunately, would be near my route back to Chicago. The dynamics were a lot more subtle than the day before, with a very large slight-risk outlook issued by SPC from the mid MS river valley southward to the Gulf coast. Initially, the tornado outlook was 2%, but later upgraded to 5% in a small area over NE Missouri and into SW Iowa. Wind and hail probabilities were 15%, with the hail coinciding near the 5% tornado outlook. The target for my chase was NE Missouri, which is where the warm front was draped. Another target area, farther west to near Kansas City and SW Iowa / SE Nebraska, was also east of an intense stacked (upper DVA and surface) low pressure area. This low pressure area even exhibited an eye-like feature on visible satellite over E Nebraska by 20z!

I left Wichita via 400 east and into the Flint Hills. Near Altoona, I took 47 east to near Franklin, and Highway 69 north to Fort Scott, and east for the long haul into Missouri and across the Ozarks to Jefferson City via Highway 54. The target area was pretty much north and northeast of Jefferson City, to and north of Mexico, MO. In this area, convergence would be maximized along the warm front, with backed winds, and at the time of peak heating. Signals pointed to a late initiation of storms here, and with a near-dusk low-level jet and boundary layer cooling causing much lower LCL's at that time. Storms farther west near the low also were producing tornadoes, but were well out of range and initiated very early, and were barely outside the 2% tornado outlook area. SPC issued mesoscale discussion 477 (east of 475) and subsequent tornado watch 116 for the target area in NE Missouri, valid until 9 PM CDT.

By roughly 6 PM, some LP supercell storms developed near and around Moberly, MO and points east. With the warm front nearly stalled, these storms became elevated over the cooler air mass to the north. Surface temperatures ranged from the upper 70's to low 60's across a short distance, with a S wind backing to ESE as one proceeded north. These LP supercells, developing well ahead of a squall line associated with the low to the west, had high bases and produced hail to at least an inch. By about 8 PM an LP storm developed east of Moberly and moved north. This storm weakened, but once it reached the boundary, it rapidly intensified and produced a tornado near Emden, Missouri after dark in Shelby County. I came within a few hundred yards of this tornado as it grazed Emden. After this tornadic supercell moved north, it eventually merged with the squall line coming in from the west near Quincy, IL.

From near Mexico and Moberly, I stuck with Highways 22, 64, and eventually 24 and 36. The Emden tornado was north of Highway 36 and crossed Highway 168. I continued east on 168 to 61 north, then 24 east towards Quincy and back across the Mississippi River into Illinois. Pretty much done with chasing, and dealing with a linear severe MCS now, I continued out of Quincy on 104 to I-174 north to Highway 110 near Carthage. I proceeded east on 136 to near Macomb for fuel stop, then north along 41 and eventually to I-74 north out of Galesburg. I took I-74 to I-88, which goes back NE to I-39 near Rochelle, and continued east on I-88 to Highway 59 north out of Aurora. This took me back to Hoffman Estates, IL and back to where I am staying in the NW suburbs by 4 AM on April 28. This terminated this successful (but long) chase trip.

 

[Paul Hadfield]

(Mods: Please add Illinois)

NAM 4KM STP painted an obvious warm front target so after finishing up errands, I headed SW with my daughter just prior to initiation for to hopefully do some leisurely time lapse on whatever might occur. Upon passage of Morrisonville on IL48, it became apparent this day might become more than just structure per the windmill image even though radar at the time was weak. Watching a well defined wall cloud passing to the south of Raymond, it was here that I gave the weather service a heads up call. Not long after I was reporting our first observed touchdown occurring just to the ENE of Raymond. Once the first tornado lifted, I re-positioned a little further east to get out of the rain/vault region. While doing so, we witnessed a second tornado somewhere east of Harvel that looked like an IV bag with a with a slender tube dangling from a bulbous funnel base. It was on the ground for maybe about ten seconds or so and unfortunately I did not get it (a young man by the name of Shae Cohen did if you want to look him up on fb). Once it lifted we watched yet another funnel try to get its act together and pass directly in front of us. The show would temporarily be over as the meso passed safely to the east after which we flanked it from the SW side and saw yet another funnel further upstream. The storm was moving at a crawl so the leisurely aspect was consistent as the entire cycle from tornado to outflow encompassed less than ten miles. All of the funnels were between 1/2 to 1 mile away and shot through a 300mm. Video was crafted as such to assist KLSX with our single tornado episode and will have additional with time including the windmill.

 

[Mike Marz]

After chasing in Oklahoma the day before, I woke up fairly early in Kansas on this day. I headed north and by early afternoon I was northeast of KC in MO waiting for initiation. Sadly, I didn't go further north into Iowa/Nebraska... I had no thoughts at all about doing that. I still can't believe there was enough CAPE for those tornadoes that occurred that far north. I targeted cells that initiated on the cold front/dryline/triple point arc. My storms were definitely rotating and showed supercell characteristics with nice rain free bases and RFD cuts/wall cloud attempts. I even notice a few brief funnels. I also got into some fairly large hail this day... much larger than the previous day, in which softballs were being predicted. Eventually this become more of a QLCS type tornado situation and I continued east with the line. I decided to head south towards the bottom end of the line, and funny, about 10 miles to my north the line wrapped up and there was a brief tornado near Cameron, Missouri. All in all, this was a very fun chase though. Got some nice hail dents in my car....

Sent from my iPhone using Stormtrack mobile app

 

[JeremyS]

Mods: Please add NE to the title

I had a very local chase for me as a tornado warned storm moved right through west Omaha about 345p. I initially was going to head over to southern Iowa, but had something come up last minute. Our local WFO mentioned the possibility of low topped supercells with 500mb temps as cold as -25 degrees moving overhead with the cutoff low. A warm front was also draped across extreme eastern Nebraska into southern Iowa. At first I sat there kicking myself watching on TV, as several tornado warned cells formed in southwest Iowa including a confirmed tornado near Stanton, IA. A couple of cells were moving up from the south towards the Omaha metro. The main cell was severe warned as it moved into the southern suburbs of Omaha. Another weaker cell was just to it's west and moved up into southwest and then western Omaha. I honestly had most of my focus on the Iowa cells as I watched on my computer.
Suddenly, I got a tornado warning on my phone. The western cell was now warned! I grabbed my stuff and headed out the door to see if anything actually looked interesting. I headed west maybe about 10 blocks, and had a decent view to my southwest. I could see a lowering that rapidly formed into a rotating wall cloud and then funnel. From my vantage point I couldn't quite see if there was ground contact. The funnel never fully condensed with the ground, but you could see little fingers come down towards the ground from the main funnel.
About this time, a confirmed touchdown was reported, and what was very surprising was the wording coming out from the NWS:

DOUGLAS NE-
344 PM CDT WED APR 27 2016

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 400 PM CDT FOR NORTH
CENTRAL DOUGLAS COUNTY...

AT 343 PM CDT...A CONFIRMED LARGE AND EXTREMELY DANGEROUS TORNADO WAS
LOCATED OVER WESTERN OMAHA...MOVING NORTH AT 20 MPH.

THIS IS A PARTICULARLY DANGEROUS SITUATION.

HAZARD...DAMAGING TORNADO.

SOURCE...WEATHER SPOTTERS CONFIRMED TORNADO.

IMPACT...YOU ARE IN A LIFE THREATENING SITUATION. FLYING DEBRIS MAY
BE DEADLY TO THOSE CAUGHT WITHOUT SHELTER. MOBILE HOMES
WILL BE DESTROYED. CONSIDERABLE DAMAGE TO
HOMES...BUSINESSES AND VEHICLES IS LIKELY AND COMPLETE
DESTRUCTION IS POSSIBLE.

AT 343 PM...AN OFF DUTY NWS EMPLOYEE OBSERVED A TORNADO ALONG 132ND
STREET JUST OF DODGE...HEADING NORTH.

I'm not sure why they called it a large and extremely dangerous tornado. It was never large or violent looking, but of course any tornado moving through a large city is dangerous.
I kept a safe distance and repositioned as the storm moved slowly north/northwest. After the initial possible touchdown, the funnel lifted and there was just mainly a wall cloud with an occasional small funnel. Just when I thought the storm was done, it really wrapped up again and this time produced a large funnel that stretched about 90% to the ground. Again, it never fully condensed to the ground but there were small fingers that kept appearing and looked like they could be in contact with the ground.
At this point the funnel/tornado was actually getting very close to where my 2 girls go to daycare so I was pretty worried. Luckily the funnel lifted fairly shortly thereafter and despite some very noticeable rotation still visible, the storm never came close to touching down again.
The NWS found 2 touchdowns. The first tornado was an EF-1 and the second was an EF-0.
http://www.weather.gov/oax/tornadoes27april2016

Here's the video I took of the storm. I apologize, the first few minutes are a little shaky as I was trying to take still pics, and also text my wife and daycare to let them know what was happening.

Of note, this is now the 3rd tornado to hit Omaha or the immediate suburbs since 2008. All 3 have been within 5 miles of my home, including one that was only 2 blocks away!