A field study was conducted in the Brazos Valley of Texas to determine the effects of temperature, humidity, and other meteorological factors on the temporal emergence pattern of boll weevil (Anthonomus grandis Boheman), and to compare the physiological and morphological conditions of emerged and trapped boll weevils. Emergence cages were placed over leaf litter in a wooded area and infested with diapausing boll weevils in the fall. Daily emergence and microclimatic conditions of the leaf litter and ambient air were monitored until the subsequent summer. Temperature, relative humidity, incident solar radiation, and precipitation were significantly greater on emergence dates than on dates with no emergence, and barometric pressure was significantly lower on emergence dates than on dates with no emergence. Emerged and trapped boll weevils were dissected to assess their morphology. Emerged boll weevils tended to exhibit greater fat body development, greater atrophy of testes, and less ovary development than trapped boll weevils. None of the emerged boll weevils were rated extra lean and no trapped boll weevils were rated fat. These results are consistent with previously-reported effects of climatic factors on weevil emergence in other areas of the Cotton Belt, and add new information about the physiological and morphological characteristics of emerged weevils. This information on the dynamics and mechanisms of overwintering provides insight that will be helpful in formulating improved predictive models, risk assessments, and pest management strategies for boll weevils.