Community Collaborative Rain, Hail and Snow Network widespread spatial variability surprised meteorologists, and former assistant state climatologist for the state of Colorado, Nolan Doesken, asked for precipitation measurements from private citizens in the area. About 300 responded to his emergency request for data. Said Doesken later, "The results of the data showed that more than 14 in. (36 cm) of rain fell over southwest Fort Collins, the area where the flood waters originated, while less than 2 in. (5 cm) of rain fell only 3-4 mi (5-6 km) east. The enthusiastic interest shown by volunteers and the great value of the data verified the need for such
Hail the hail to the radar, and the echo is further away from the radar than the actual location of the hail on the same radial path, forming a cone of weaker reflectivities. More recently, the polarization properties of weather radar returns have been analyzed to differentiate between hail and heavy rain. The use of differential reflectivity (formula_1), in combination with horizontal reflectivity (formula_2) has led to a variety of hail classification algorithms. Visible satellite imagery is beginning to be used to detect hail, but false alarm rates remain high using this method. The size of hailstones is best determined by