Ok, let me give this a try and see if I can help it make sense.
I'll start with the morning of July 15. When the system checked things at 3:17am, your moisture balance was low (.09in) but the weather forecast was for enough rain that day to cover the Crop Evapotranspiration that day, so it sent you a notification that it was not going to water. But that rain never showed up at your weather station (KNAK) on July 15, and so 0 precipitation was recorded.
The rain instead showed up after midnite on July 16, and KNAK got .36 inches of rain. This occurred before 3:17am, so now you had more than enough water for the day, and it did not water.
OK -- now to July 26 and July 27.
Jul 26 was recorded from midnite last night. As of that time, your weather station, KNAK, had gotten 0 precipitation.It rained lightly at your house last night, but it did not rain at your weather station.
Jul 27 is a forecast. As of your posting, the forecast is for .10 in of rain today.
Here's the math to read the chart from day to day:
PMB = Previous Moisture Balance
Irr = Irrigation (Adding water)
Precip = Precipation (adding water, will be what happened if the weather station shows, or it is an estimate of what you are going to get if is says Forecasted)
ET = Crop Evapotranspiration (what water your plants are going to use today and is going to disappear from your soil)
PMB + Irr + Precip - ET = Current Moisture Balance
For a day in the past, the Current Moisture Balance is what really happened
When the system checks things (in your case now at 4:21am), if the Current Moisture Balance is greater than 0, the system will not water. If the Current Moisture Balance is negative, the system will water.
Rachio has recently changed the Crop Coefficient for Cool Season Grass to 0.8 - depending on when you set your flex schedule up, you may be able to just change it on each zone to 0.8. If you can't change it, you'll need to create a new flex schedule and delete your old one so that you have the ability to adjust crop coefficient. Changing to .8 will better reflect how much water your grass is using and will cause it to water a little more often.
Is the KNAK weather station close to you? If not, you might want to look at using a PWS that might better reflect the precipitation you are getting at your house.
Now as for those texts you got on July 17 and Jul 18 saying that is was going to water, I'm totally puzzled!!!! I can understand why it DIDN'T water, but I don't get why it told you it was going to. Maybe someone smarter than me can figure that one out!