General Climatological Setup

      I.     Model output data in the days preceding the flood gave excellent guidance regarding the building potential.  Mention of flooding potential was made one-two days in advance of the event in several products.   As an example, check out the Colorado State Forecast Discussion from Saturday the 26th of July for Sunday night.       II.   The flood occurred in an environment considered synoptically favorable for severe weather on the high Plains of the United States.   This included low-level upslope flow and high surface dewpoints associated with the passage of a cold front.    

      Doswell, C.A. III, 1980: Synoptic-scale environments associated with high Plains
      severe thunderstorms.   Bull. Amer. Meteor. Soc., 66, 1388-1400.

      III.   There was an upper-level ridge on the morning of the event which shifted just slightly east of the affected area by evening.     Weak to moderate shortwaves were embedded in the flow.    

      Maddox, R.A., L.R. Hoxit, C.F. Chappell, and F. Caracena, 1978: Comparison
      meteorological aspects of the Big Thompson and Rapid City flash floods.   Mon.
      Wea. Rev., 106(3), 375-389.

      IV.   The flood occurred during a period (July 25th through August 7th) when a severe thunderstorm event of some sort is expected somewhere along the Front Range of north-central Colorado.     This two-week period is associated with the so-called southwestern U.S. summer monsoon .  

      Weaver, J. F., and N. J. Doesken, 1990: Recurrence probability - a different
      approach.   Weather, 45(9), 333-339.

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