I never published this particular account from one of my only freelance chases of 2011. Although overshadowed by the devastation of April 27, the April 14-16, 2011 outbreak was one of the more significant outbreaks of the 2011 season. I was able to get out of class in time to experience this day in the field as supercells developed across the southeast.
Utilizing a
combination of the NAM WRF, European, and RUC HRRR model runs, I forecasted the
initiation of a discrete thunderstorm in West Central Louisiana in Toledo Bend
country around 6am CDT. This forecast
came to fruition, with three storms initiating along an outflow boundary
produced by an ongoing MCS from the previous afternoon over the Ark-LA-Tex
region. Of the three storms that
initiated, the northernmost storm became the dominant storm eventually going
supercellular as it moved into a more favorable shear environment east of the
Mississippi River. This storm went on to
produce an EF-3 tornado in Jackson, MS.
Due to class responsibilities, I wasn’t able to depart KMLU
until 10:30am CDT. I initially targeted
a discrete cluster of cells that formed along the cold front associated with
this very dynamic storm system. As I
approached this small cluster of cells, I noted that the bases of these storms
were extremely high, despite the fact that the southernmost storm featured
notable rotation in the upper levels of the storm. At this time, I noticed only modest forward
storm motion speeds (~30 knots) associated with the discrete supercells in East
Central Mississippi. This prompted me to
continue driving eastward toward this are to put myself in position for further
convective development to the south.
 |
| Rapidly rotating wall cloud moving over Meridian, MS. |
As I approached the Jackson metro area, I encountered a
major traffic jam that was the result of damage caused by the EF3 tornado that
was associated with the initial discrete cell of the event. To add to this problem, two new discrete
cells were beginning to go supercellular and were heading toward the Jackson
metro area. This forced me to have to
detour around a large stretch of I-20.
Once I was able to exit the interstate, I drove north on the Natchez
Trace Parkway before driving East through Jackson on highways 49 and 25. This took me out of position to make a play
on the two cells south of I-20. However,
both cells possessed easterly components that the first cell did not. This allowed me to get back on I-20 and get
ahead of the northernmost storm to set myself up for an intercept around
Meridian, MS. As this storm approached
my location in Meridian, I observed and documented the forward flank downdraft
advancing on my location. Extremely warm
and moist air was noted before precipitation started. Shortly after precipitation began, I observed
a large rapidly rotating wall cloud about a mile to my south. I was able to observe the rain curtains
“wrapping” around the wall cloud itself all the way to the surface from my
location. After documenting and
reporting this to the National Weather Service, I decided to continue tracking
east into Western Alabama.
Upon further investigation of my storm’s characteristics on
radar, it was evident that it was beginning to become and HP mess and was
losing strength. Therefore, I decided to
drive south in an effort to intercept the southernmost storm of the
cluster. However, I ran into another
road block due to previous tornado damage, and was forced to turn around and
re-strategize. With additional
semi-discrete cells forming along the cold front in southwest Mississippi, I
decided to reposition to the south along US 45 in Eastern Mississippi to wait
for storms to come to me. This strategy
allowed me to intercept two more storms on this day. I observed, documented and reported a tornado
that crossed US 45 southeast of Quitman and a rotating wall cloud that crossed
US 45 about 2.5 miles south of Waynesboro, MS before deciding to call it a
chase. This chased ended when I arrived
in NIB shortly after midnight on the 16th.
 |
| Wall Cloud associated with the southernmost cell that formed along the cold front in western Misissippi and southern Louisiana. |
Chase Stats
Storms Intercepted: 3
Wall Clouds: 2 (Meridian, MS, 5.5 S Waynesboro, MS)
Tornadoes: 1 (Quittman, MS)
Hail: Pea Sized (Quittman, MS)
Distance: ~800 miles
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