FLOOD01363

• County: Statewide
• Title: Colorado High Plains Thunderstorm Systems - A Descriptive Radar-Synoptic Climatology
• Date: 6/1/1974
• Prepared By: CSU
• Floodplain - Doc Type: Educational/Technical/Reference Information

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PART II

RESULTS AND INTERPRETATION

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1.0 RADAR ECHO GENESIS CHARACTERISTICS

Space-Time Distribution of Conveetive Genesis

An analysis of the distribution of radar echo genesis supports

the importance of elevated topography in initiating convective systems.

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The influences of Colorado's topography on convective system initi- ~

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ation investigated by this study were related to:

1. Time of initial echo observation - describes the median time

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the first echo of the day was observed in each grid square.

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2. Time of "maximum echo" production - describes the hour during

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which each grid square was observed to produce its maximum

number of echoes which later becamil thunderstorms over summers

of 1970-1972.

3, The relationship of grid square elevation to the number of

initial echoes observed over the grid square ~lich later E~~~

into thunderstorms of at least 30,000 feet height and ~ 30 dBZ.

Earliest echo initiation time lvaS observed over the mountains ai1d

adjacent ridges which jut out onto the plains. Figure H shows the

most frequently observed time of initial echo observation in each gr~d

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square, It is clear that the earliest echo initiation occurs at ele-

vations above 6000 feet bett-Jeen 1000-1200 MDT. On the plains echo

initiation times are during the early to midafternoon period. Plains'

echoes referenced here are not related to echo systems which originated

over the mountains and migrated east, It is interesting to note the

relatively late time of ccho initiation near Akron (AKO) and La Junta

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