Search Results
You are looking at 1 - 1 of 1 items for :
- Author or Editor: R. E. Orville x
- Journal of Applied Meteorology and Climatology x
- Refine by Access: All Content x
Abstract
The mean annual flash density, thunderstorm duration, and flash rates were calculated using 121.7 million cloud-to-ground lightning flashes in the continental United States for the period 1989–96. Florida had flash densities over 11 flashes km−2 yr−1, while the Midwest, Oklahoma, Texas, and the Gulf Coast had densities greater than 7 flashes km−2 yr−1. There was a relative minimum in flash density (three flashes km−2 yr−1) in the Appalachian Mountains and Missouri. Thunderstorm duration values exceeded 120 h yr−1 in Florida and 105 h yr−1 in New Mexico, Arizona, and the Gulf Coast. The maximum annual flash rates exceeded 45 flashes h−1 in the Midwest, along the Florida coasts, and along the mid-Atlantic coast with the minimum flash rates, 15 flashes h−1, over the Appalachian and Rocky Mountains. The relationship between thunderstorm duration and flash density is Flash_Density = 0.024(Flash_Hours)1.29 producing expected flash densities that are within 30% of the measured densities for over 70% of the nation, with the greatest errors, over 80%, in the intermountain region of the Rockies.
Abstract
The mean annual flash density, thunderstorm duration, and flash rates were calculated using 121.7 million cloud-to-ground lightning flashes in the continental United States for the period 1989–96. Florida had flash densities over 11 flashes km−2 yr−1, while the Midwest, Oklahoma, Texas, and the Gulf Coast had densities greater than 7 flashes km−2 yr−1. There was a relative minimum in flash density (three flashes km−2 yr−1) in the Appalachian Mountains and Missouri. Thunderstorm duration values exceeded 120 h yr−1 in Florida and 105 h yr−1 in New Mexico, Arizona, and the Gulf Coast. The maximum annual flash rates exceeded 45 flashes h−1 in the Midwest, along the Florida coasts, and along the mid-Atlantic coast with the minimum flash rates, 15 flashes h−1, over the Appalachian and Rocky Mountains. The relationship between thunderstorm duration and flash density is Flash_Density = 0.024(Flash_Hours)1.29 producing expected flash densities that are within 30% of the measured densities for over 70% of the nation, with the greatest errors, over 80%, in the intermountain region of the Rockies.
