Hypothetical sounding for thermal turbulence exercise

Question

It is the summer season in the Southeast United States and convective activity is expected during the afternoon. Use the 1200 UTC sounding below to forecast the turbulence intensity in and around the convection that develops later in the day. Use the Eastern Airlines Method to determine the turbulence intensity.

What is the CCL?
Enter your answer in the text box below, then click Done.

CCL = hPa

Answer:
From the sounding plot, the CCL is 740 hPa (see graphic).

Determine delta-T (°C)
Enter your answer in the text box below, then click Done.

Delta-T = °C

Answer: Delta-T is approximately 7°C (see graphic).

From the CCL, proceed upward along a moist adiabat to 400 hPa, where parcel temperature (T')=-18°C and the sounding temperature (T) is -25°C. Therefore:
Delta-T = T'-T = (-18) - (-25) = 7°C.
What turbulence intensity would you expect?
Please select an answer from the list below.

Turbulence intensity =
Answer: Severe turbulence.

From the table on page 2, a delta-T of 7°C falls in the 7-9°C range, which indicates the potential for severe turbulence.

Based on this sounding, aviation interests would be notified that this potentially dangerous situation could present itself during afternoon convection.

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