Forecast Exercise: Question 3

To answer this question and others that follow, you first need to open the Interactive Skew-T with this sounding.

Now let's examine the sounding for that afternoon in some detail and determine some of the thermodynamic parameters based on this sounding. Determine the following, then click Done.

LCL:       Correct: 915 hPa

Convective Temperature (Tc):       Correct: 32.5°C

Total Totals index(TT):       Correct: 60

SWEAT:       Correct: 579

Lifted index (LI):       Correct: -8.2

CAPE:       Correct: 2192 J/kg

CIN:       Correct: -95 j/kg

0-6 km shear magnitude:       Correct: 87 kt (43 m/s)

BRN:       Correct: 24

Compare your answers with the correct answers above.

Based on the parameters above, summarize your thoughts on the severe weather potential. Enter your response in the text box below, then click Done to see an expert opinion.

Expert Opinion: The TT (60), SWEAT (579), and LI (-8) all exceed critical instability threshold values indicating a significant potential for severe weather. The convective temperature is 32°C (90°F) and this may be a limiting factor given that it is early May. However, there is little CIN (-95 J/kg) to be overcome, and if a surface parcel is lifted to the LCL has very little negative area to overcome to continue rising into the upper troposphere. In addition, much of the negative area associated with the capping inversion may be wiped out if the inversion layer is lifted and stretched. The 0-6 km shear magnitude (87 kt, 43 m/s) is moderate for severe weather and there is significant CAPE (2192 j/kg), lending further evidence to the favorable severe weather potential. The BRN is 24 which gives indication that there is an environment conducive to severe convection with the possibility of the development of supercells.
Previous       Next