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the basin where the town of Buffalo Creek is located which, coincidentally, is also the portion of the basin that had been ravaged by a forest fire two months earlier (Table 4 and Fig. I). The lack of vegetation in the burn area was suggested to be an important reason for the severity of the flash flood (see the Appendix). The one-hour Flash Flood Guidance (FFG) rainfall valid for Jefferson County as issued by the NWS Missouri Basin River Forecast Center earlier in the day was 53.3 mm (2.1 inches; see dashed line in Fig. 14c). FFG rainfall represents the approximate amount of basin-averaged rainfall over a given duration that is needed to bring small streams to bankfull (Sweeney 1992), It is estimated daily for rainfall durations of 1,3, and 6 hours by the operational hydrologic forecast models at the RFCs. NWS forecasters often compare the model-estimated FFG rainfall with observed gauge- or radar-derived rainfall in real time to access flash flood risk. Since this rainfall event was of approximately one-hour duration, the one-hour FFG is the appropriate one to examine here. The basin-maximum one-hour rainfall exceeded the one-hour FFG from 0257 to 0332 UTC, however the basin-averaged rainfall at its peak at 0303 UTC was about three times smaller than the one-hour FFG. As a result, a comparison ofFFG with basin-maximum radar rainfall instead of basin-averaged rainfall would have been more appropriate in alerting forecasters to the potential flood threat for this case. The basin-maximum one-hour rainfall fust exceeded the FFG value beginning at 0257 UTC which corresponds closely to the time when the public reported that the Buffalo Creek came out of its banks. The intensity and small size of this rainfall event likely made the model-estimated FFG rainfall inappropriate for this event even if you don't consider the unmodelled effect of the forest fire on the infiltration characteristics and resulting 23 v ,/