Although it is commonly thought that forecast uncertainty should decrease as the lead time to a significant weather event diminishes, this is often not the case for severe thunderstorm and tornado forecasting. This results from the more limited predictability of both the mesoscale pre-convective and near-storm environments, which provide a controlling influence on convective development and evolution, and the individual thunderstorms themselves, which generally have low predictability. Thus, it is not uncommon that key details such as timing of thunderstorm initiation, mode, and intensity are often not known even several hours in advance. In fact, for the 5 February outbreak the ramping up' of the severe risk as the event neared was particularly challenging, as the likely details of thunderstorm development became murkier 12-18 hours in advance as additional observational and numerical model data became available. These data increased concerns that the cap would hold ahead of an approaching surface cold front, and storms associated with a subtle, southern stream mid-upper level impulse might overspread much of southern Missouri, northern Arkansas and western parts of Kentucky and Tennessee during the day stabilizing a large portion of the region. The difficult operational challenges in assessing increasing volumes of higher resolution data in the forecast process, especially when these data conflict with other model data, observations and conceptual models of the atmosphere, will be illustrated by this case.