Another blast from the past…quick METAR lesson…
You can find hourly, 3-hourly, 6-hourly, and 24-hourly precip totals in the raw METARs. It hasn’t rained in Yuma lately so I’ll use Albany, NY (ALB) as an example. Hourly rainfall is reported every hour that rain is detected. They are coded by Pxxxx where P0001 is 0.01" of rain, P0025 is 0.25" of rain, and P0000 is a trace of rain. 3-hourly rainfall is reported at 3z, 9z, 15z, and 21z. 6-hourly rainfall is reported 0z, 6z, 12z, and 18z. 24-hour rainfall is reported 12z.
Here we go…text in BOLD is what I added…
METAR KALB 150551Z 00000KT 7SM -RA FEW038 SCT075 OVC090 16/14 A2971 RMK AO2 RAE19B37 SLP060 P0000 60019 T01560144 10211 20156 58005 - P0000 = a trace past hour ; 60019 = 0.19" in the last 6 hours
METAR KALB 150651Z 17006KT 7SM -RA BKN034 OVC100 16/14 A2970 RMK AO2 SLP057 P0004 T01610139 - 0.04" past hour
METAR KALB 150751Z 19007KT 7SM BKN095 16/15 A2969 RMK AO2 RAE47 SLP053 P0002 T01610150 - 0.02" past hour
METAR KALB 150851Z 19008KT 8SM OVC100 17/15 A2969 RMK AO2 SLP054 60006 T01670150 55006 - no rain past hour ; 60006 = 0.06" last 3 hours (the hourlies over the last 3 hours add up)
METAR KALB 150951Z 21004KT 6SM -RA BR BKN038 BKN055 OVC090 16/16 A2971 RMK AO2 RAB10 SLP061 P0000 T01610156 - trace past hour
METAR KALB 151051Z 16005KT 5SM -RA BR OVC034 17/16 A2972 RMK AO2 SLP063 P0002 T01670156 - 0.02" past hour
METAR KALB 151151Z 18007KT 3SM RA BR FEW017 OVC038 17/16 A2973 RMK AO2 SLP066 P0006 60014 70033 T01670156 10167 20156 51013 - 0.06" past hour ; 60014 = 0.14" past 6 hours ; 70033 = 0.33" past 24 hours
Hope this helps for the future. Here you can find the last 24 hours of raw METARs for Yuma (YUM).
http://www.uswx.com/us/stn/?code=c&n=24&stn=KYUM
Station name and the amount of obs displayed can be changed.