To determine whether unfavorable weather conditions affect the number and acuity of visits to a pediatric emergency department (ED), a retrospective analysis was conducted of children's hospital ED visits and weather conditions utilizing an ED log book and local climatological data during the year 1993. Visits, intensive care unit (ICU) admissions, non-ICU admissions, time periods with favorable weather (TPF), and time periods with unfavorable weather (TPUF) were measured. Each day of the year was divided into two time periods. The time periods were labeled TPF or TPUF based on certain weather conditions. There were 632 (86%) TPF and 98 (14%) TPUF. The number of visits, non-ICU admissions, and ICU admissions during TPF were 13,008 (88%), 1,031 (87%) and 121 (86%), respectively. The number of visits, non-ICU admissions, and ICU admissions during TPUF were 1,720 (12%), 148 (13%), and 19 (14%), respectively. No significant differences in visits and admissions during TPF and TPUF were identified. Also, there was no difference identified when the distribution of visits and admissions was examined during TPUF due to different weather factors, eg, low temperature, precipitation, etc. The results show that unfavorable weather due to the types of weather factors discussed does not affect the number or the nature of visits to a pediatric ED.