Hail
Hail of up to 4.5 inches in diameter were reported in the data set (22 April 1995 in Bossier Parish), but more than 75% of the reports showed diameters less than or equal to1.75 inches.  As can be seen below, most (81%) hail is reported as falling in the northern part of the state.  In northern Louisiana, hail is most likely to fall in the spring with a primary maximum in April and a secondary maximum in November.  In southern Louisiana, most hail storms occur in spring also but the month of peak activity is March with a secondary maximum in December.

Total number of hail report in Louisiana by month for the northern (latitude > 31¡ N) and southern parts of the state.
Data source:Storm Prediction Center of the National Weather Service

As might be expected, a distinct peak in hail events occurs in the afternoon hours; however, this maximum is greatly exaggerated in northern Louisiana while a much flatter distribution in observed in the southern part of the state.  Clearly the timing of these peaks is related to the diurnal nature of thunderstorms.

Total number of hail reports by hour of the day for the northern (latitude > 31¡ N) and southern parts of the state.
Data source:Storm Prediction Center of the National Weather Service


The average number of hail events per year, normalized to a 1000 sq. mile area, has been computed for each parish.  The spatial distribution of this variable or of hail events displayed by the diameter of the hail can be viewed using ESRI's Internet Map Server (IMS) running at ULM.  For a brief description of how to use the tools in IMS, click here.

As indicated above, hail events show a distinct geographic distribution in Louisiana.  To view the map of the average number of hail events per year per 1000 sq. miles, click here or on the image below.  As can be seen from the map, hail events occur with the greatest frequency (darker colors) in the northwestern part of the state and decrease in frequency as one moves toward the southeast.  Sabine Parish had the greatest frequency of hail occurrences during the period, averaging nearly 29 hail events per year per 1000 sq. miles.  The fewest number of hail storms occurred in St. Mary Parish, where the average is approximately 2 hail events per year per 1000 sq. miles.

 

To view the map of each hail event displayed by the diameter of the hail, click here or on the image below.