NA_Merged_24hr_Sep_2018
General --September is the first month of meteorological autumn in the Northern Hemisphere. --September lightning over the U.S. occurs in organized systems, clusters, and lines that gradually diminish from north to south during the month. --Central America, Cuba, Florida, the Gulf of Mexico, and Mexico have very frequent daily lightning all month. --The Southwest Monsoon retreats from northwest to western Mexico through the month. --Canada and Alaska have minimal lightning in September. --The east-west aligned equatorial trough, the Intertropical Convergence Zone, is intermittent over the eastern North Pacific away from Central America. Specific --06 to 12 September: Florida is well defined by afternoon lightning each day. --09 to 16 September: Hurricane Florence moves from SE to NW to North Carolina, and stalls. --19 September: Mexico covered by thunderstorms. --28 to 29 September: Cyclonic circulation north of Hawaii. ~Ron Holle
Oct 2, 2018 Webmaster Archive