These profiles add value to the horizontal composites produced previously. The horizontal composite charts revealed that thundersnow events occur in otherwise unremarkable, snowbearing extratropical cyclones. Working on the assumption that some feature (instability) makes these events unique, and that convection resulting from instability is the source of charge separation for lightning production, these profiles were constructed. What appears most clearly is the presence of an elevated layer of potential instability in events northwest of a cyclone center (N=8). While not deep, it generally exists in a region of deep moisture and forcing for ascent. Cases of thundersnow northeast of a cyclone center (N=4) are potentially neutral, but with profiles rich in moisture and again forcing for ascent. Although not statistically significant, these profiles would seem to support the hypothesis of potential instability related convection dominating in thundersnow cases northwest of a cyclone and potential symmetric instability related convection dominating in cases occurring northeast of the cyclone center.
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