Lab 6: Soundings Fall 2010
1) Using the provided Skew-T diagram, and using the data obtained from your
section’s upper air balloon launch, plot the following data onto the Skew-T:
 Temperature
 Dewpoint
 Winds
2) After the data is plotted, clearly indicate the following levels and/or areas.
Use a skew-T reference guide or use the website
http://www.theweatherprediction.com/habyhints for help with each item.
Since there are a lot of “Habyhints” from the given website, the number of the
“Habyhint” is given in parentheses (with HH) for easy reference. Assume a
surface based parcel where appropriate.
 Lifted Condensation Level (LCL) (HH #299)
 Surface Wet Bulb Temperature (Normand’s Rule…use http://wwwdas.uwyo.edu/~geerts/cwx/notes/chap08/normand.html )
 Level of Free Convection (LFC) (HH #309)
 Equilibrium Level (EL) (HH #310)
 Shade and label the Convective Available Potential Energy (CAPE)
(HH #305)
 Convective Condensation Level (CCL) (HH #320)
 Convective Temperature
 Shade Convective Inhibition (CINH) (HH#306) (a different color)
 Identify major layers of Conditional Instability
 Identify Cap (HH #308)
 Identify any temperature inversions (significant inversions)
 Identify the primary tropopause, and any additional ones.*
3) Calculate the following values. Use the following definitions:
Note errors in this, find a new ref for 2011!
http://amsglossary.allenpress.com/glossary/search?id=stability-index1
 Lifted Index
 K-Index
 Total Totals (TT)
 Showalter Index
*Tropopause Definition and Finding (Cameron’s favorite thing):
The first tropopause (i.e., the conventional tropopause) is defined as
the lowest level at which the lapse rate decreases to 2 K/km or
less, and the average lapse rate from this level to any level
within the next higher 2 km does not exceed 2 K/km.
If above the first tropopause the average lapse rate between any
level and all higher levels within 1 km exceed 3 K/km, then a second
tropopause is defined by the same criterion as under the statement
above. This tropopause may be either within or above the 1 km layer.
A level otherwise satisfying the definition of tropopause, but
occuring at an altitude below that of the 500 mb level will not be
designated a tropopause unless it is the only level satisfying the
definition and the average lapse rate fails to exceed 3 K/km over at
least 1 km in any higher layer.