High Plains Drifter

disclaimer:  "The meteorological views/forecast thinking expressed are those solely of the author of this blog
and do not necessarily represent those of official National Weather Service forecast products,
therefore read and enjoy at your own risk and edification!"

November 3, 2006

Chase Acct: October 26 (Southwest KS) [part 2, "The Chase"]

Filed under: Chase Accounts,Oct 26, 2006,Special Cases,Storm Chasing — Mike U @ 11:48 pm

Looking to the south-southeast at a dusty tornado about 4 miles northeast of Minneola around 4:35pm CDT on Oct 26, 2006I departed Dodge City around 1:45pm or so, with the plan just to head south into the clearing area immediately south of the front so I could get a visual on things with respect to vertical Cu development.  Low clouds were parting around the Clark-Ford Co. line with the temperature reaching the lower 60s.  I made it as far south as the Hwy 160 junction just a few miles north of Big Basin… as the main band of convective looking clouds were pretty much right along this zone.  I had a temperature of about 66°F at this location around 2:30pm. Scanning the skies from west to above my through east… it didn’t appear obvious yet where the best focus along this boundary was, and with this in mind, I decided to sit back for a little bit.  I decided to call work (NWS-DDC) and let them know I was out, and provided them an observation since my current location happened to be one of the areas in our forecast area devoid of surface obs.  At 2:30pm, I had an east-southeast wind about 10 mph with 67°F.  If you look at a surface obs map at this time, you wouldn’t see any southeast winds…as there was only an extremely narrow corridor of east to southeast winds.  Perhaps 10 miles south of me, winds were probably out of the southwest with very dry dewpoints in the deeply mixed dry intrusion air stream. 

Fairly soft towering Cu dominated the sky in a NW to SE orientation along this front.  I was beginning to get itchy feet and decided to move.  There was a small base developing to my west… almost immediately overhead…as well as to my east-southeast, and all this stuff was slowly pivoting north.  I figured I needed to favor east a little bit, so I drove back north on 283 to 4 S Minneola, where I drove east on an unpaved farm road approaching Clark State Lake.  Driving north, then east to this new location, my temperature dropped to about 62°F with the wind out of the east-northeast…only 12 miles northeast from that previous location I was at.  I found a good vantage point here now, near Clark St. Lake, with small towers trying to get going all along the boundary to my west through southeast.  Through about 3:15pm or so, I still didn’t observe anything that prompted me to re-position myself… i.e. a significant, dark base with pronounced towering Cu growth… that is, until about maybe 3:20 or 3:25pm or so (estimation).  Off to my distant west-northwest, I could tell it was getting increasingly dark, and I saw the first hint of the best, sharpest Cu devleopment atop this darker mass to the northwest some 40 miles away.  It was at this point (with visions of 10 April 2005 running through my mind in terms of how things might "unzip" down the boundary beginning in the northwest first…then southeast later), that I decided to race back east to Hwy 283 to investigate this area, that appeared to be some 20 miles or so northwest of Minneola.  I passed through Minneola (for the 2nd time of the day) going back north.  Once I got out of Minneola heading north, I could certainly pick out what appeared to be a very impressive, long and dark updraft base looking WSW through NW.  There even appeared to be a lowering of the cloud base on the northern portion of this base.  I turned west on Wrangler Road, which is 3 miles north of the Ford-Clark County line (5 N Minneola).  The time was now around 3:40pm, and the weather radio alarmed for the first tornado warning.  The TOR was for that precise area where I was seeing this lowering to my distant west-northwest.  The chase is on now!!

The very elongated base was very promising…suggesting very significant updrafting over a pretty large corridor extending south of where the TOR was issued.  Continuing west, I kept my eye on the main area of interest to my northwest I had not even considered, however out of the corner of my eye, I see this thin "sheath" looking thing to my southwest.  Possibly a landspout tornado!  After watching this for about 15 seconds, I noticed a debris cloud beneath this feature confirming a weak tornadic circulation beneath this feature.  Time was about 3:50pm and I immediately called NWS DDC with a report.  I made it clear that this was farther south of where they were indicating possible tornado on radar and that it was farther south along the flank.  I turned south 1 mile on 101 Rd. then west again on X Rd in the far southwestern tip of Ford County…crossing into extreme southeastern Gray Co.  I stopped around 4:00pm at a location 1 mile west of county line with Ford and 2.5 miles north of county line with Meade.  I was directly underneath the flanking updraft.  I observed another dusty, weakly tornadic circulation to my southeast down the flanking line, but my main interest was still just immediately north of me.  The problem was, the main storm was now getting too close to the cool air, as my temperature was about 57°F, yet there was fairly modest cloud base rotation at various points from my immedate NNW to my immediate southeast.  I was probably not in the best location, as tornadogenesis could occur almost on top of me! 

I had to keep up with the storm, so I headed back east two miles, then north on 101 Rd. (back into Ford County now)… not even two miles north, the sky was eerily dark with impressive rotation just a mile up the road.  Cloud bases were also extremely low, making it tough to really see much structure.  After stopping a couple times to monitor this, I crawled north to stay with this rotation.  I continued about two miles more north before making the turn east as I was getting into more rain.  I drove one mile east in the rain, and decided I was too far north now.  I headed back south on 102 (Crooked Ck.) Rd.  It was at this point that I needed to stay south along the flanking towers, and stay away from this cold air.  The 3rd tornadic circulation I spotted now at 4:23pm to my southeast also confirmed this thinking :)   It was now "get south as quick as you can" mode.  Thankfully, the unpaved roads I was on were well-grated, so the rain didn’t make them extremely slippery.  I stopped briefly to photograph the distant, dusty tornado to my southeast then continued to drive south.  I called to report this tornado at around 4:25pm, and it dissipated while I was on the phone with the report.  I was at the intersection of Wrangler & 102 Rd. at this point, where I headed back to the east. 

About 5 miles later looking south-southeast, a higher contrast (being a bit closer) dusty vortex developed at 4:30pm.  I turned south on 108 Rd.  About 1.5 miles later, the tornado to my south-southeast developed an impressive black looking dust cloud.  Wow!  At this same time, I noticed tumbleweeds swirling right in front of me and to my right in the adjacent field about 50-100 yards away… Wow again!  Sensory-overload at this point with vorticity everywhere!  The tornado to the south was now getting closer, since I was driving towards it, and I stopped briefly to photograph close-in shots of the circulation at the ground.  I then turned east again on the County Line Rd. (Ford-Clark).  At this point, I am now about 4.5 miles northwest of Minneola.  After I turned east, I immediately stopped to photograph this beautiful, tall, dusty tornado churning away over baren farmland!!  Classic!  At various points, you could distinguish a faint condensation funnel above the intense ground level rotation/debris cloud.  Time was now 4:35pm and I photographed from this location for about 5 minutes as the tornado travelled northeast.  I used my 80-400mm lens exclusively at this location and got some interesting images of the base of this tornado with trucker traffic driving along Hwy 54 just on the other side of the tornado.  The tornado was 2 miles away and Hwy 54 was 3.  The circulation at ground level became indistinguishable around 4:40pm and I used that opportunity to keep driving east to stay with it.  I reached Hwy 283 now with the tornado to my southwest approaching me!  The tornado now redeveloped again with a classic, narrow condensation funnel about 1/3 of the way to the surface and a black, dusty debris cloud underneath… fantastic!  (zoom-in of debris cloud) Time 4:42pm… I was obviously watching the movement of this thing with extreme caution, since it was essentially coming towards me.  Needless to say, the car was running and I as shooting from right next to my passenger door!  I began to notice some right to left forward motion, so the tornado was going to miss me to the south.  The black debris cloud dissipated, but what was left was a sky full of tumbleweeds… a countless number of them!  I was close enough to the ground circulation, that with my 400mm lens, I could discern the very tight rotation in the tumbleweeds about 1/2 mile to my south-southwest.  The circulation was approaching Hwy 283 now to my south.  I set myself up to photograph the tornado crossing the road, anticipating the shot.  Fortunately (for the sakes of the shot), the tumbleweed debris remained intact as the circulation crossed the road.  A sherrif was on the opposite side of the tornado watching this event unfold.  The weak tornado crossed the road causing no damage to the powerlines, however a large quantity of tumbleweeds accumulated on the powerlines itself, marking where the tornado crossed. Time was now 4:48.

This tornado then ultimately dissipated in a farm field to my southeast, narrowly missing some farm structures.  Not to be outdone, a larger scale storm circulation was now crossing Hwy 283 to my *north*!!  A fairly large, "cigar" shaped funnel was now getting ready to cross the road, now keep in mind I’m in the same spot as where I was watching the southern tornado cross Hwy 283.  This weak tornado crossed the highway to my north at about 4:52pm.  It would be until several days later that I noticed a 2nd formidable funnel on the right hand side of one of my images, on the other side of Hwy 283.  This would match the LSR report of "2 tornadoes at the same time, one on either side of Highway 283", at about this exact time ~4:53pm.  I get ready to leave this location, but before so, another dusty tornado was evident to my southeast probably 5 miles away under one of the new developing towers.  I drove into Minneola (for the 3rd time), then head northeast on Hwy 54 a few minutes before 5:00pm.  When I got out of town and had a view again to the north, much to my surprise (or maybe not!), was yet another full-fledged tornado probably 3-4 miles away.  This tornado appeared visually to be the strongest one I saw this day… it had a narrow, but fully condensed condensation funnel in contact with the ground and certainly appeared to be associated with some larger scale tornado cyclone that evolved from some supercellular processes.  3 miles northeast of Minneola, I headed north to get closer to this area of interest.  This tornado was no longer visible as I was driving north as it appeared to become wrapped in rain/hail.  I drove north about 3.5 miles and noticed a significantly occluded "tornado cyclone" feature with a bit of a tip near the bottom of this feature… although it wasn’t in contact with the ground, there was likely some weakly tornadic circulation beneath it.  Time was now 5:05pm, and this feature was probably the remaining circulation from the full-condensation tornado I saw about 7 minutes prior.  This would be the last tornado I would see for the day. 

I drove south back to Hwy 54 and decided to keep chasing, heading northeast towards Bucklin.  I entered light rain and low clouds with about 53°F… yuck!  I then drove south on Hwy 34 to get back into the warm air.  Along the drive south on Hwy 34, I had a great view of the low-topped Cb structure of the storms to my northeast.  This storm produced a tornado north of Protection, however I never did see it, as it was too far away and I had hills blocking my view below the cloud base.  After photographing the Cbs, I headed to Hwy 160 then drove west through Ashland and began my trek backhome…which took me through Minneola for the 4th and final time of the day :)  

This was a fairly remarkable chase and was extra-special for being so close to home — one of the reasons I love it so much out here in Southwest Kansas!  This chase marks my 4th October tornado day, dating back to my first October tornado in 1998 in Yocemento, KS. 

Click for detailed map of events

Photo Gallery:


Mike Umscheid


November 2, 2006

Chase Acct: October 26 (Southwest KS) [part 1, "The Forecast"]

Filed under: Chase Accounts,Oct 26, 2006,Special Cases,Storm Chasing — Mike U @ 2:36 am

Given the uniqueness of this tornado event, I am breaking this chase account into two parts, the forecast and then the chase itself, for the purpose of documenting all the decision making processes that went on leading to the success of this chase.  I will begin by stating that, yes, my geographical starting location (Dodge City) played a huge role in my decision to chase…being only 30 miles from the target area.  I was working a 9pm to 5am shift earlier that morning, preparing the Southwest Kansas forecast for the time period Oct 26-27th… so I had a very clear idea of the overall synoptic scale situation impacting my forecast area.  For brevity, I will not go into detail on the overall meteorology involved, but I would encourage you to read the Area Forecast Discussion (AFD) I wrote earlier that morning pertaining to the meteorology for October 26th SW Kansas forecast.  You will see me mention things like mid level potential vorticity (PV) and maximized potential instability in the 800-600mb layer at the nose of the mid level dry intrusion.  These are meteorological parameters unfamiliar to many storm chasers and amateur or new severe storms forecasters (mainly because they aren’t available on the internet) — yet are very key factors in many "cold-core" tornado events, I am beginning to find.  While I didn’t mention the possibility of tornadoes in my AFD, I mentioned the key things that seem to be very important for "cold-core" tornado events.  The reason I did not mention tornadoes in my AFD was the simple fact that the surface front appeard to be just too far south of my forecast area, and that any convection in my forecast area would be largely elevated above the shallow stable layer (but just barely).  This was based primarily on the high-resolution NAM model.  Intuition told me, however, that if the front arced back north at the nose of the dry intrusion/PV anomaly into SW Kansas, then insolation could really make things interesting with an enhanced tornado risk. 

At any rate, I got home at 5am and went to bed with absolutely no intention to storm chase, primarily because I had to work again later that evening at 9:00pm, which would restrict me to a very tight leash within an hour or two of Dodge City.  I woke up around 12:30 or so, and the first thing I did when I woke up was check out the weather, since I am always interested in seeing how my forecast is verifying in complicated weather situations like this one.  Much to my surprise, I was seeing the visible satellite image revealing sunshine over the southern counties from Hugoton east to Meade to near Ashland.  We were still in low stratus and drizzle in Dodge City with a northeast wind and 53°F.  See the visible satellite image below, at 1745z (12:45pm CDT):

1km visible satellite image at 1745 UTC on 26 October 2006.  The yellow oval indicates my chase target area after looking at this image and the 17z short-fuse composite.

I then looked at the 17z short-fuse composite and noticed a large surface moisture convergence bullseye over far southwest Kansas near the edge of the clearing on the visible satellite (see image below).  Also of important note was that the surface theta-e ridge was nosing westward immediately north of the OK state border south of Dodge City.  So, putting everything together from just these two charts told me everything I needed to know… the front was farther north and we could certainly be looking at more than just "small hail" that I had put in the forecast for this area earlier that morning at work!  To me, it was looking much more like a potentially tornadic situation after looking at just these two bits of information.  With nothing planned that day until I was due in to work again at 9pm that evening, I decided to give this a shot and head due south from Dodge City to investigate this convective environment.  I was seeing some similarities to 10 April 2005... as storms were developing near the Colorado border… and as the day progressed, storms kept "unzipping" southeast at the nose of the mid level dry intrusion.  When this "unzipping" hits the higher low level theta-e, then tornadic storms could be possible given the massive amounts of nearly stationary surface frontogenesis and vertical vorticity…not to mention enhanced horizontal streamwise vorticity (from 0-1km vertical wind shear) for tilting.  I kept re-creating in my mind how this might unfold a-la 10 April 2005.  I had my camera gear pretty much all packed and ready to go, as I usually do for impromptu situations just like this one.  Since I do not shoot video anymore while storm chasing, the only gear I had to assemble was my photography pack and my laptop computer for GPS navigation.  I didn’t even have my Alltel mobile internet setup going, since I can’t use it (my new Dell laptop does not have a PC card slot, but an ExpressCard slot, so I have to buy a USB adapter)… something I was going to address in the off-season.  I left Dodge City for the drive south around 1:45pm or so.  Chase account to be continued on next blog post…

The short-fuse composite (chart #1) that we are generating every hour at NWS-DDC.  The valid time of this chart is 17z on 26 October, which coincides pretty closely with the visible satellite image above.  Note the theta-e ridge nosing westward towards the maximum area of surface convergence.

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