Monday 21st February 1st shift Dan Johnson 1245 Leave WISP operations center. On this mission is Dan Johnson and Joy Xie. 1430 ARRIVE AT FIRST DESTINATION. This is 22 km from the CHILL radar site at 77.5 degrees. The site is on 68 Rd. ENE from CHILL 6.5 miles east of the intersection of Hwy. 392 or approximately 28 km ENE of Greeley. There is no snow falling here. We will be taking an air bag sample with Brian Jesse from CSU and air filter samples also. 1441 Started air bag sample. We will only fill a 50 l bag since the pump we are using only has a 2-3 l/min capacity. 1500 Finished air bag sample 1520 Started air filter sample. Flow rate is about 2 l/min. Skies are still gray and overcast. Still no snowfall since arrival 1546 Finished air filter sample (~ 50 l) 1550 We are leaving Greeley site since no snow falling here and are headed to the K-band site. 1615 Entering Greeley on Hwy. 34 westbound. Snow is starting to fall 1620 Three miles south of Greeley on Hwy. 85, snow has stopped falling. 1644 Three miles west of Platteville on Hwy. 66, snow has started to fall again. 1707 ARRIVE AT SECOND DESTINATION. We are located about 0.5 km south of K-band on 320 Rd. It is snowing heavy here. Snow type from visual observation is large dendritic aggregates. 1711 Chemistry bag is out 1715 Up to 2 cm diameter aggregates observed falling. Also have observed 4 mm diameter dendrite crystals. 1718 Calibration photos taken 1720 Snow sample #1: Large dendritic branch about 3 mm in length Heavily rimed dendritic branch Stellar crystal 1729 Winds are NE about 10 mph. Snow falling is very wet and heavy and is mainly dendrites and aggregates. Aggregates are a little smaller than at 1707. Snow sample #2: Aggregates heavily rimed stellar with plates on end of branches 4 mm dendrite, very slightly rimed Fern-like dendritic branch - has "fish-bone" appearance probably due to melting of crystal in mild air Heavily rimed clump of crystals Large dendritic branches with very little rime on branches 1744 Chemistry samples #1a and #1b taken. 1745 Chemistry bag ready for new samples. 1746 Snow falling now is mainly crystals about 1-2 mm in diameter. There are few aggregates falling now. 1748 Snow sample #3: Smaller aggregate, slightly rimed dendrite, and side planes 0.75 mm length column with small caps on ends Side planes, slightly rimed Large plate with plates on end and also columns on end. 1 mm broad-branched crystal. Branches are short Plate with short branches on the end Hollow column which is uncapped Small plate about 0.75 mm diameter 1808 Winds are NE about 10 mph. Snow crystals are smaller in size and snow is falling more lightly. Snow sample #4: Stellar with lots of growth on end of branches Plates and columns. Columns appear to be solid Plates and sheaths Thick column, sheaths, plates Broad-branched crystal about 2 mm diameter Small plate about 0.25 mm diameter Uncapped columns. 1826 Snow is falling lightly now 1831 Chemistry samples #2a and #2b taken. 1834 Chemistry bag ready for new samples. 1836 Winds are NNE at approximately 10 mph. Snow is falling moderately and is both crystals and small aggregates. Snow sample #5: Rimed dendritic aggregate with column in branch Column Side planes 1846 Winds NNE at 10-15 mph. Snow falling moderately and is largely crystals about 1 mm diameter. There seems to be more columns in the samples we are taking with time. Snow sample #6: 0.8 mm length uncapped column Stellar branches with columns embedded Small plate about 0.5 mm diameter embedded in dendrite branches Broken branch which is fern shaped Long column which is bullet shaped on end. 1907 Snow falling heavier again. Winds are NNE at about 10-15mph. Snow has many smaller aggregates about 1 cm in diameter and some very large aggregates up to 4 cm diameter. Snow sample #7: Long sheaths and small plates (some crystals are smaller now ~ 0.5 mm diameter) Rimed stellar aggregates Some needles Plates with some embedded needles Short capped hollow columns Heavily rimed particle, almost graupel like 1922 Snow falling moderately heavy. It appears visually to be aggregates 0.5 cm diameter made up of heavily rimed dendrites. 1930 Chemistry samples #3a and #3b taken. 1933 Chemistry bag ready for new samples. 1934 Snow sample #8: Plate on top of plate. Center of plate is stellar. Very small plates, small uncapped hollow columns Branches from a broad-branched crystal Fragments of dendrite branches and a column Plate 1953 Snow sample #9: Column Fragment - looks like half a plate Column with side planes Small plates about 0.2 mm diameter and fragments Columns, fragments, stellars, stellar branches 2030 Snow falling light to moderately. Winds NNE about 10 mph. Operations center is taking 1 hour break. Small crystals and small aggregates falling. 2035 Chemistry samples #4a and #4b taken. 2045 Leaving the K-band site and heading back to NCAR