Question 2 of 2
If you have not already done so, you will need to open the interactive skew-T diagram with a preloaded sounding to complete this exercise.
Assume that you anticipate significant advection of low-level moisture into your area.
Using the click and drag feature on the interactive skew-T diagram,
increase the dewpoint in the 950-1000 hPa layer by 10°C.
Then answer the following questions based on the modified sounding.
(For each question, write your answer in the text box, then click Done.)
a) What is the Convective Condensation Level (CCL)?
CCL =
hPa
The correct answer is about 790 hPa.
b) What is the lifted index (LI)?
LI =
The correct answer is about -7.
c) What is the CAPE?
CAPE =
J/kg
The correct answer is about 2500-2600.
d) What is the convective potential?
a. Low
b. Moderate
c. High
Incorrect. The convective potential is pretty high, with the CCL lower by nearly 100 hPa, a LI=-8, and CAPE of about 2500 J/kg, all indicators of potential for significant convection. Note that no surface heating occurred, there was only an increase in moisture. The message here is that increasing low-level moisture can significantly destabilize a sounding, even in the absence of surface heating.
Correct. The convective potential is pretty high, with the CCL lower by nearly 100 hPa, a LI=-8, and CAPE of about 2500 J/kg, all indicators of potential for significant convection. Note that no surface heating occurred, there was only an increase in moisture. The message here is that increasing low-level moisture can significantly destabilize a sounding, even in the absence of surface heating.