sum_intensities_over_dateranges.py

import datetime
import pandas as pd

_TIMESTAMP_FORMAT = '%Y-%m-%d %H:%M'

time_ranges = [
    (datetime.datetime(2019, 6, 16, 14, 2), datetime.datetime(2019, 6, 17, 7, 2)),
    (datetime.datetime(2019, 8, 15, 12, 30), datetime.datetime(2019, 8, 17, 8, 30))
]

# DataFrame for testing
# rdfAnd = pd.DataFrame.from_records(
#     ((datetime.datetime(2019, 6, 16, 17, 00), 11), ),
#     columns=['date_time', 'Intensity']
# )

records = []
for start_timestamp, end_timestamp in time_ranges:
    daterange_string = f'From {start_timestamp.strftime(_TIMESTAMP_FORMAT)} to {end_timestamp.strftime(_TIMESTAMP_FORMAT)}'
    accumulated_intensity = total_rain = rdfAnd[
            (rdfAnd['date_time'] >= start_timestamp) &
            (rdfAnd['date_time'] <= end_timestamp)
    ]['Intensity'].sum()
    records.append((daterange_string, accumulated_intensity))

intensity_ranges = pd.DataFrame.from_records(records, columns=['daterange', 'accumulated_intensity'])
print(intensity_ranges)