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Severe storm initiation and development from satellite infrared imagery and Rawinsonde dataThe geographical distribution of potential temperatures, mixing ratio, and streamlines of flow patterns at 850, 700, and 500 mb heights are used to understand the prestorm convection and the horizontal convergence of moisture. From the analysis of 21 tornadoes the following conclusions are reached: (1) Strong horizontal convergence of moisture appeared at the 850, 700, and 500 mb levels in the area 12 hours before the storm formation; (2) An abundantly moist atmosphere below 3 km (700 mb) becomes convectively unstable during the time period between 12 and 24 hours before the initiation of the severe storms; (3) Strong winds veering with height with direction parallel to the movement of a dryline, surface fronts, etc; (4) During a 36-hour period, a tropopause height in the areas of interest is lowest at the time of tornadic cloud formation; (5) A train of gravity waves is detected before and during the cloud formation period. Rapid-scan infrared imagery provides near real-time information on the life cycle of the storm which can be summarized as follows: (1) Enhanced convection produced an overshooting cloud top penetrating above the tropopause, making the mass density of the overshooting cloud much greater than the mass density of the surrounding air; (2) The overshooting cloud top collapsed at the end of the mature stage of the cloud development; (3) The tornado touchdown followed the collapse of the overshooting cloud top.
Document ID
19840026801
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Hung, R. J.
(Alabama Univ. Huntsville, United States)
Smith, R. E.
(NASA Marshall Space Flight Center Huntsville, AL, United States)
West, G. S.
(NASA Marshall Space Flight Center Huntsville, AL, United States)
Date Acquired
August 12, 2013
Publication Date
September 1, 1984
Publication Information
Publication: NASA(MSFC FY-84 Atmospheric Processes Res. Rev.
Subject Category
Meteorology And Climatology
Accession Number
84N34872
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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