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<br />period was near 0.5 mmh-1 and steady. -The top of the 90 percent relative humi- <br />dity contour was near 3 km over Sheridan. The wind direction was predominately <br />out of thE! south. up' to 300 mb. <br /> <br />The increase of cloud top height near 1800, 7 January was in response to the <br />passage of an upper level front, evidenced by the decrease of temperature from <br />1500 to 2100 above 650 mb. Precipitation increased to 2 mmh-1. Supercooled <br />water decreased to 0.05 mm. As the front passed the winds decreased from <br />10 ms-1 to 5 ms-1 in the high relative humidity zone below 3 km. After the <br />front movl~d past Kingvale, precipitation averaged less than 0.5 mmh-1 for the <br />next 15 hours. Supercooled water amounts during this period were near 0.05 mm <br />with peaks to 0.50 mm associated w'ith embedded convection. ThE! supercooled <br />water obsl=rved duri ng thi s time was produced primari ly by COnVE!ct ion. Oro- <br />graphic forcing was unlikely based on the low wind speeds in the moist layers <br />of the atmosphere. The center of the low circulation passed over Sheridan at <br />0300 as the winds went calm. Soon thereafter, winds were weak and out of the <br />north, marking the end of the storm. <br /> <br />Discussion <br /> <br />The 6-8 January 1985 storm was one of seven storms associated with a cutoff <br />low or large amplitude shortwave at 400 N latitude. Large amplitude shortwave <br />'cases were combined with the cutoff storms because the observed wind shifts were <br />very similar. Five of the seven storms were cutoff lows and an had complete <br />radiometer data sets. Two of the seven storms were associated with the large <br />amplitude shortwaves, ~ut neither had radiometer data available due to rain at <br />Kingvale. The evolution of supercooled water in large amplitude shortwaves will <br />not be discussed due to the unavailability of radiometer data. <br /> <br />21 <br />