Hail in Iowa, June 26, 1999

A warm and fairly humid airmass was in place over Iowa. Surface temperatures warmed into the upper 80s to low 90s with dew point temperatures in the mid 60s to low 70s. A cold front was approaching the state from the northwest. Thunderstorms fired up along the northern portion of the front across Minnesota initially. Though the CAPE values over Iowa were near 5000 J/kg, thunderstorms were not able to fire initially due to a mid level cap. Storms back developed across central into south central Minnesota, then eventually developed south-southwest into Iowa. With the freezing level near 14,500 feet, it was difficult for the storms to produce hail. It took VIL values of 70 kg/m**2 to produce severe hail. The storms produced high winds and hail in Minnesota, but the winds in Iowa were below severe levels. Hail of three quarters inch to nearly one inch in diameter pelted Emmet County as the most intense storms moved across the county. In addition to the hail, the storms dropped one to two inches of rain as they passed. Local flooding was a problem, but it was not widespread.