World_Apr_2017_06hr
--April is the middle month of meteorological spring in the Northern Hemisphere, and of autumn in the Southern Hemisphere. --By tracking the latest hours in white, the overhead sun can be seen moving east to west on a daily basis. --Thunderstorms travel west to east over the middle and higher latitudes in both hemispheres, and are stationary or move more slowly from east to west in the tropics. ~Ron Holle
May 2, 2017 Webmaster Archive
Northern Hemisphere --Alaska, Canada, China, Europe, and Russia have only a few April days with thunderstorms. --Lightning over and near Japan is present in outbreaks on several days. --April lightning over the United States is very frequent in well-organized lines and clusters that usually start on the Plains and move eastward for several days. --Thunderstorms move to the east-southeast on many April days along the southern boundary of the Himalayas. --India lightning gradually increases through April, mainly in the southeast and northwest regions. ~Ron Holle
May 3, 2017 9:32:27 PM Dave Fincher
Tropics --The east-west aligned equatorial trough, the Intertropical Convergence Zone, is frequently apparent over the eastern North Pacific, Indian Ocean, and western Atlantic. Sometimes there are two parallel lines in an east-west orientation. --Lightning over Africa is frequent near the Equator and moves from the east but has minimal organization for more than a few hours. --Daily thunderstorms over Brazil move from the east, but individual storms do not travel far. --The major islands and land areas of tropical Southeast Asia have thunderstorms nearly every afternoon in sea breezes and along mountain slopes. Motion is often from west to east. --Central America and Mexico have minimal lightning until the last half of April. ~Ron Holle
May 3, 2017 9:32:43 PM Dave Fincher
Southern Hemisphere --Lightning is much less frequent over Australia than in the previous few months. --The Andes south of the equator provide a sharp western boundary in a NNW-SSE line and no lightning occurs over the cold water offshore of the Andes. ~Ron Holle
May 3, 2017 9:33:18 PM Dave Fincher
--02 April: First of several large thunderstorm complexes form in southern U.S. Plains and move east. --02 to 06 April: A broad cyclonic circulation is located over the western half of the Mediterranean Sea. --03 to 06 April: Frequent lightning over northern Pakistan. --04 to 05 April: Scattered lightning over the North Atlantic between Iceland and Norway. --06 to 09 April: Turkey has frequent lightning, moving west to east. --08 to 12 April: Lines of thunderstorms move west to east across Libya. --12 to 13 April: Storms form in Texas and move south into Mexico. --12 to 14 April: Lightning moves southwest to northeast across Saudi Arabia and Middle East. --13 and 17 April: Long lines of lightning extend southeast from South Africa. --18 to 23 April: Large thunderstorm complexes move southeast from Bangladesh and northeast India. --29 to 30 April: Long, intense west to east line of lightning extends from Texas to east coast. ~Ron Holle
May 3, 2017 9:33:33 PM Dave Fincher