Wednesday 26th January Dan Johnson 0135 Leave RAP operations center 0322 ARRIVE AT FIRST DESTINATION. Equipment set up 170 degrees 20 km from CHILL at the intersection of 49 RD (N-S) and 36 RD (E-W) or 20 km SE of Greeley at 40 14' 48" lat and 104 36' 10" long. 0324 Moderate snow falling at the time of equipment set up. 0330 First chemistry bag out. Ops. reporting 15-20 dBZ echo in region over van. Light snow falling. 0341 heavily rimed (dry growth) of aggregates. Needles also observed. 0400 First chemistry sample taken from bag set out at 0330. Second chemistry bag set up. Snow falling lightly. Snow is rimed aggregates Microphotography set up. First photos are calibration scans. 0413 Photos begin of snow samples. Also attempt video of snow crystals Cannot obtain good image of snow crystals on monitor from video. Image shows on dark filter but only periodically with full light from microscope. Snow sample #1: Hollow columns, clean Rimed aggregates Plates, clean Double broad-branch crystals Needles 0424 Snow sample #2: Clumps of needles Rimed needles Rimed chunks Hollow columns Spatial columns 0430 Moderate snow falling made up of small crystals Clumps of needles falling at this time 0432 Snow sample #3: Needles (good quality for photo) Spatial plates 3-D plates Regular plate Spatial plates with clumps in center Needle or plate on side More needles 0445 Wind has changed to the NE and is blowing harder (low-level jet?) Fairly heavy snow falling of smaller flakes. 0449 Second chemistry sample taken from the 0400 bag. 0454 Snow sample #4: Large aggregates Capped columns Thick plates hollow columns 3-D plates, plates growing on end 3-D drop-centered irregular columns 3-D hollow columns and plates Drop-centered 3-D needle with plate on end Assemblage of plates and side planes. Drop-centered 3-D plates END OF FILM ROLL #1 0513 Wind has dropped off substantially. 0515 Snow sample #5: 3-D plates Radiating assemblage of plates, side planes Hollow columns Capped hollow column 0520 Snow sample #6: Hollow columns 3-D plates Capped columns (capped on both ends) Bullet? Side planes 0530 Windy outside and colder. Temp. is -5 C at van. 0545 Snow yet falling. Wind is more from the north. Wind approximately NNE. Very small crystals falling. 0550 Snow sample #7: Largely side planes Plate growing broad branches Hollow columns Capped column Side plane (log) 0605 Snow falling lightly Visibility more than 2 miles outside Crystals have changed over last 10 min. to become rimed clear droplets Snow sample #8: Heavily rimed aggregates with clear rimed droplets Heavily rimed clumps 0620 Snow falling very lightly Snow sample #9: Slightly rimed side planes Lightly rimed broad branches Stellar crystal, slightly rimed Hollow column lightly rimed broad branches and needles moderately rimed chunk 0635 Snow falling lightly with some large flakes A couple of bands of snow are moving from SW of CHILL towards foothills Temp. outside is -7 C. 0636 Snow sample #10: Lightly rimed clumps Stellar crystals 0645 Snow has almost finished falling FINISHED AT SITE #1 20 km SSE of Greeley. 0815 At Greeley, snow is falling again. Snow is made up largely of stellars. 0835 Do not enter 0935 ARRIVE AT 2ND DESTINATION. Location is 14 km @ 12 degrees from K band .5 km north of intersection of Hwy. 66 and 5 Rd. or 5 miles ENE from Longmont at 40 10' 26" lat. and 105 0' 16" long. 0937 Light snow falling. Light winds are now from the east. Snow crystals are small. Chem. bag #3 is set up. 0945 Heavily rimed columns, rosettes and plates falling. Small flakes approximately 100 microns in size. Snow falling lightly Snow sample #11: Heavily rimed rosettes Heavily rimed capped columns, clear rime Heavily rimed side planes Heavily rimed plates 3-D broad-branched dendrite, lightly rimed 1000 Very light snow now falling. Many crystals are heavily rimed plates and columns Snow sample #12: Heavily rimed columns, capped columns, and plates Short column (clean) END OF FILM #2 Asymmetric plate Heavily rimed side plane Heavily rimed bullet rosette 1015 chemistry sample #3 taken from bag set out at 0937 1016 Clean bag ready for chemistry sample #4 1018 Very small crystals falling and are lightly rimed Snow sample #13: (sample very clean) Clean side planes Plates Short columns 1020 Snowing very lightly with little riming 1024 SHUT DOWN FROM SITE #2 12 km NNE of K Band Contents from Chem. bag dumped out. 1101 ARRIVE AT 3RD DESTINATION - approximately 8 km west of Greeley approximately .5 km south of intersection of Hwy. 34 and 25 Rd. Request of Ops. to stop at this location. 1102 Light snow is falling, sky is bright with approximately 1 mile visibility. Winds are lightly from the east. 1103 Chemistry bag set up for sample #4. 1105 Snow crystals are mainly lightly rimed broad branched 1110 Snow sample #14: Lightly rimed broad branches with very small cloud droplets Tiny heavily rimed bullets Radiating assemblages of plates lightly rimed Double broad branched crystal from one drop 1120 Snow falling lightly and made up largely of columns and plates Temp. outside is mild - low 30's? Snow sample #15: Capped columns and radiating plates Few broad-branched crystals Many hollow capped columns 1128 Chemistry sample #4 taken from bag set up at 1103. 1130 Snow sample #16: Radiating plates Capped columns SHUT DOWN OPERATIONS FOR 1/26/94 Head back to RAP 1245 Arrive back at RAP.