According to the Glossary of Meteorology, a funnel cloud is any rotating cloud pendant from a cumulus or cumulonimbus, and thus most tornadoes are included under this definition. Among many meteorologists, the funnel cloud term is strictly defined as a rotating cloud which is not associated with strong winds at the surface, and condensation funnel is a broad term for any rotating cloud below a cumuliform cloud.Tornadoes often begin as funnel clouds with no associated strong winds at the surface, and not all funnel clouds evolve into tornadoes. Most tornadoes produce strong winds at the surface while the visible funnel is still above the ground, so it is difficult to discern the difference between a funnel cloud and a tornado from a distance. Outbreaks and families
Occasionally, a single storm will produce more than one tornado, either simultaneously or in succession. Multiple tornadoes produced by the same storm cell are referred to as a "tornado family". Several tornadoes are sometimes spawned from the same large-scale storm system. If there is no break in activity, this is considered a tornado outbreak (although the term "tornado outbreak" has various definitions). A period of several successive days with tornado outbreaks in the same general area (spawned by multiple weather systems) is a tornado outbreak sequence, occasionally called an extended tornado outbreak. Characteristics
Size and shape
Most tornadoes take on the appearance of a narrow funnel, a few hundred meters (yards) across, with a small cloud of debris near the ground. Tornadoes may be obscured completely by rain or dust.
Astasia-abasia refers to the inability to either stand or walk in a normal manner. Astasia refers to the inability to stand upright unassisted. Abasia refers to lack of motor coordination in walking. The term abasia literally means that the base of gait (the lateral distance between the two feet) is inconstant or unmeasurable. When seen in conversion disorder, the gait is bizarre and is not suggestive of a specific organic lesion: often the patient sways wildly and nearly falls, recovering at the last moment. An acquired total inability to stand and walk can be seen in organic neurological diseases, including stroke, Parkinsons disease, damage to the cerebellum, Guillain–Barré syndrome, normal pressure hydrocephalus and many others. In normal pressure hydrocephalus, for example, when the condition remains untreated, the patients gait becomes shortened, with frequent shuffling and falls; eventually standing, sitting, and even rolling over in bed become impossible. This advanced state is referred to as "hydrocephalic astasia-abasia". Phobias
Astasia and/or abasia are  associated with the corresponding fears of walking and/or standing, variously called stasophobia, basophobia, stasiphobia, basiphobia, stasobasophobia, stasibasiphobia, etc., sometimes turning into pathological forms, i.e., phobias. See also
Blocqs disease, an illness named after Paul Oscar Blocq

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