Kinematic and moisture characteristics of a non-precipitating cold front observed during IHOP. Part II: Alongfront structure

This study, the first of two parts, is focused on describing structures in the across-front dimension. Coarsely resolved observations from the operational network and dropsondes deployed over a 200-km distance centered on the front are combined with higher-resolution observations from in situ sensors, Doppler radars, a microwave radiometer, and a differential absorption lidar that were collected across a similar to 40-km swath that straddled a similar to 100-km segment of the front.', The northeast-southwest-oriented cold front moved toward the southeast at similar to 8-10 m s(-1) during the morning hours, but its motion slowed to less than 1 m s(-1) in the afternoon.

In the early afternoon, the cold front separated cool air with a northerly component flow of 2-4 m s(-1) from a 10-km-wide band of hot, dry air with 5 m s(-1) winds out of the south-southwest. The average updraft at the frontal interface was similar to 0.5 m s(-1) and slightly tilted back toward the cool air. A dryline was located to the southeast of the front, separating the hot, dry air mass from a warm, moist air mass composed of 10 m s(-1) southerly winds.