2008 CHASE ACCOUNTS

APRIL 24, 2008: NORTHWEST KANSAS (SUPERCELL)

Brian Thalken and myself observed a long-lived supercell in northwest Kansas.  After finishing supper in Arapahoe, NE, we saw on radar several cells showing signs of intensifying within a region of steep low-level lapse rates south and north of Goodland, KS.  One of these storms quickly displayed supercellular characteristics east of Goodland, which we quickly decided to target.  After maneuvering through a series of farm roads, we eventually reached highway 36 east of Oberlin, KS.  We then gained a position between Oberlin and Selden on highway 83 (time was ~7:30 pm CDT), and parked directly east of the approaching supercell (this was our initial view of the storm).  The storm was developing mid-level inflow bands, but was also high based due to the rather limited low-level moisture and steep low-level lapse rate environment.  We hoped that as it moved east into deeper moisture, the storm would further intensify...we also knew that low-level shear/hodograph curvature was forecast to increase substantially by sunset...so we remained patient.  By 7:50-8:00 pm, a second storm approached and merged with the storm that we were observing.  It was after this merger took place that things really got interesting.  Surface inflow steadily increased as we moved south down to Selden, KS (estimated to be around 40-50 mph), and mid-level rotation became much more apparent (inflow band picture #1, inflow band picture #2).  The storm started taking a hard right turn, and by 8:30 pm, a large wall cloud  began to develope (see picture here) as rain cooled air was pulled into the updraft base from the forward flank downdraft positioned to the north.  We both believed (as I'm sure everyone else did as well) that the storm was getting very close to producing a tornado.  However, a cold surge of outflow rapidly undercut the updraft base, causing the wall cloud to dissipate and the storm to accelerate further to the south and east.  Interesting mid-level inflow features were still present (such as the one here) though, and new wall clouds formed every 10-20 minutes.  We then made our way to highway 24 east of Hoxie, KS.  A new mesocyclone developed east of the old one as we went south, with updraft rotation further intensifying and taking on a horseshoe shape.  Darkness began to set in as we approached Hill City, KS...with photography becoming more challenging.  Plus, I had to work at 8:00 am the next day...so we gave up on this storm just before it moved through the Hill City area (~9:30 pm).  The storm continued to move east across northern KS through the night, and produced a 1/2 mile wide EF2 tornado near Beloit, KS at around midnight.  Regardless, Brian and I were happy with what we saw...it was a great way to start off the 2008 season.

MAY 5, 2008: WESTCENTRAL KANSAS (SUPERCELL)

Brian Thalken and myself chose a target along an outflow boundary oriented northwest to southeast (located north and east of Garden City, KS).  We reached this location by mid afternoon, shortly after thunderstorm initiation took place.  We had to deal with two storms located in close proximity to each other (both displaying occasional supercell characteristics).  The northern storm had a large rain free base and dark forward flank precip core (see picture here and here), while the southern storm displayed a somewhat flanged base and slightly better visual indications of mid-level rotation (see picture here, and here).  Rotation within the southern storm continued to increase through 5:30 pm (CDT), so we left the northern storm and gained a position directly in the path of the southern (picture of mid-level inflow band).  As we moved southeast along highway 50, we began to hear reports over the radio of softball size hail falling back to the northwest over Garden City (all we observed on the southeast side of the storm were dimes).  This picture shows what the storm looked like at around 6 pm as it was producing large hail at GCK (note the stinger shaped inflow band here and here).  We could still observe the northern storm (through a veil of rain) and noted a developing wall cloud, which eventually (6:45 pm) developed into a large lowering that we thought was almost in contact with the ground.  However, we could never verify whether a tornado was in progress.  Meanwhile, the southern supercell became progressively cold and outflow dominant as it moved toward Dodge City, KS.  We gave up on the cell during this stage, and went back to Garden City to observe the hail damage (where 4 inch piles of hail drifts were still present on the ground).

MAY 6, 2008: WESTCENTRAL KANSAS (HIGH BASED SUPERCELL)

Started the day off in Garden City, KS, trying to decide whether to target the KS/NE border, SW Kansas, or west central KS.  Early afternoon TCU's a county or so to the west and a maturing storm crossing the KS/CO border convinced us that west central KS would work.  A high based multicell developed 30 miles to our west by 3:30 pm (CDT)...so we drove about 10 miles north of GCK, and then west towards the updraft base (which was initially hidden behind a veil of glaciated anvil).  By 4 pm, we were directly in the path of this developing storm (here is one view looking west/southwest), and interestingly, a brief surge of outflow from the storms rain core to the north pushed south and appeared to initiate broad cloud base rotation.  This rotation continued to intensify during the next 30 minutes, and was fascinating to watch given we were almost directly under the base (view of the agitated rotating cloud base).  A clear slot and RFD developed by 4:30 pm, kicking up large amounts of dust to our west and south, as well as numerous gustnadoes (developing gustnado to our west/northwest).  The RFD also caused the storm to accelerate to the east, which eventually led the gustnadoes to begin chasing us down a series of farm roads.  We eventually maneuvered east of highway 83 (going down the same farm road we were on the previous day), with a wall cloud quickly developing by 4:55 pm (here).  A funnel was briefly produced beneath this wall cloud, but disappeared along with the lowering in a matter of 5 minutes.  The storm progressively took on a cold look during the next hour, but mid-level updraft rotation was still observed, as a weak flanking line wrapped cyclonically into the main updraft tower (here).  We eventually gave up on this storm (~6-7 pm time frame) as it morphed with neighboring cells into a squall-line/bow echo.  As we began the drive back home north on highway 83, we got a chance to obtain some decent mammatus photography (here, here, and here).