Monday, 12 January 2004
Are there weather holes? An objective analysis
Room 4AB
Matthew D. Parker, University of Nebraska, Lincoln, NE; and J. C. Knievel
Poster PDF
(1.1 MB)
In the authors' experience, most meteorologists and interested lay people lament that they live in a weather hole, a location that storms often barely miss or near which approaching storms often dissipate. The authors use 6 years of composite data from the WSR--88D network to explore whether each of 21 target cities, selected for their prominent meteorological communities, is truly a weather hole or a hot spot (the counterpart to a hole). The target cities are statistically compared to a population of randomly selected points from throughout the contiguous United States. Holes and hot spots are defined by relating the frequency of echoes at a target to that in the surrounding region, as well as the probability that echoes near the target will be followed some specified time later by echoes at that target.
There are, indeed, mesoscale patterns of variability in the 6-year sample. The frequency of echoes >20 dBZ is not significantly higher at any city compared to its surroundings, and the topography near some cities makes interpreting their radar climatologies difficult. For the rest, when only echoes >40 dBZ (i.e., convective precipitation) are considered, signs of holes and hot spots do appear. However, very few stations actually meet the authors' criteria for being either a hole or a hot spot (the courterpart to a hole). Overall, during the 6 years studied, nearly all of the selected targets experienced heavy precipitation from convective storms about as often as did their surrounding areas. These results suggest that meteorologists are unnecessarily downcast about the frequency of storms in their hometowns, perhaps because there have been few climatological studies of convective behavior prior to now.
Supplementary URL: