The Kansas-Oklahoma Tornado Outbreak
of April 26, 1991

Exercise
Case Study Links
Case Study Page
Event Data


1.
At 4:00 p.m., find the dry line.

Answer

 

2. At 4:00 p.m., what areas can be ruled out for severe weather to occur?

Answer


3.
What happens to the dryline between 4:00 p.m. and 8:00 p.m. in Kansas? in Oklahoma? Can the dryline be found looking at information other than surface maps? (Hint: You might focus on available products at 7:30 p.m.)

Surface Maps

4:00 p.m. (2100 UTC) 5:00 p.m. (2200 UTC)
6:00 p.m. (2300 UTC) 7:00 p.m. (0000 UTC)
8:00 p.m. (0100 UTC)

Radar Images from Oklahoma City (KOKC) at
7:30 p.m.

 
BREF 1 BVEL 1
BREF 2 BVEL 2
BREF 3 BVEL 3
VIL  

Answer

 

4. At 6:28 p.m., identify the prominent features in Garfield and Noble counties on the Tilt 1 Base reflectivity scan.

Answer


5.
Also at 6:28 p.m., examine the reflectivity scans on Tilt 2 and Tilt 3. What feature on Tilt 3 seems to be correlated with the storm as seen on Tilt 1?

Answer


6.
What pattern in the Base Velocity scan at 6:28 p.m. is correlated with the feature seen in Question 4?

BVEL 1 BVEL 2 BVEL 3

Answer


7.
Examine the VIL product at 6:34 p.m. Where is the largest hail? Where is this relative to the reflectivity and velocity patterns observed during the same volume scan?

Answer


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