My godmother lives outside of Bozeman and I recall her telling me they had a couple inches of ash all over
Nice obs outta MT from back then
MSO,1980-05-20 06:00,KMSO 200600Z 30007KT 3SM FU OVC/// BKN200 14/07 A2997 RMK D1 VOLCANIC ASH DEPTH 0.3 IN /003 SLP139 8/001 T01390067
WEY,1980-05-19 14:00,KWEY 191400Z 00000KT 5SM FG OVC025 07/05 A//// RMK THN COATING OF ASH ON GND/ 400/NOSPL SLP180 T00670050
BZN,1980-05-19 12:00,KBZN 191200Z 14007KT 5SM FU OVC020 12/07 A3004 RMK VOLCANIC ASH CVRS GROUND / SLP147 T01170067 50000
HVR,1980-05-19 14:15,KHVR 191415Z 24010KT 1 1/4SM OVC030 A2982 RMK PK WND /VSBY RDCD BY VOLCANIC ASH SLPNO 50000
SFF,1980-05-20 00:00,METAR KSFF 200000Z 24005KT 1/4SM OVC001 21/06 A2992 RMK VOLCANIC ASH SLPNO T02110061