A few days of bad weather and parked partially under trees for almost a week is not a problem with enough Battery Storage. The Lithium batteries do not require to be fully charged either and any amount of extra energy is stored efficiently.
Starting in Borrego Springs, CA and driving to Las Vegas, NV for CES 2019. When staying at the Circus Circus RV park is tall building but mainly trees shading our solar panels from 11 AM.
Only after driving to Lake Havasu and parking in the desert were we able to get a full charge.
The stretch started with a rainy day in the Desert January 5th. Very little energy was captured from below the thick cloud cover. Only 3.7 kWh for the whole day.
When staying in Las Vegas January 9th was the trees and buildings making even a good sunny day produce limited output. Only 5.3 kWh.
After driving to Lake Havasu is a full day of sun on January 13th able to bring our batteries back to full charge with 12.8 kWh.
Having enough battery storage to last multiple days of limited energy from the sun is essential to be 100% off-grid. We of course also turned off the Water Heater that is using 3-4 kWh per day and used gas for cooking food.
Even after 8 days was enough battery capacity left so if needed could we have stayed 5 days more.