Dear Authors:
As you can see from the referee report, the revisions largely address the referee comments. After consideration of the referee comments and close reading of the manuscript, I would like the following comments to be addressed prior to publication. Thank you.

Line 136: The use of the PM2.5 lens on the AMS needs to be explicitly stated and perhaps cited (Peck et al., 2016) since it is not standard yet.

Line 151: The software is written for Igor, it is not IGOR software.

Lines 244-259: (weekday/weekend analysis) Can you please add details about weekday/weekend statistics (supplement would be fine). In particular, some indication of the observed variability in the particle class concentrations in Figs. 2 and S5 would help the reader judge the significance of the weekday/weekend claims. In particular, the Biomass burning-soil effect looks like it may be mostly driven by 1 weekend event in mid August.

Line 273-275: Please clarify that the PMF analysis is for the AMS data.

Lines 260-278: I find this section confusing. It seems that the conclusion at the end is that biomass burning is not a source of the biomass burning-soil particles. Is this correct? If so, would it be better to give the class a different name?

Lines 287-293: This acidity indicator is highly uncertain (e.g., Hennigan et al., (2015)). Given the presence of Na+, it is even more likely to be erroneous under these conditions. Please add a discussion regarding the limitations of this acidity indicator and its impacts on your conclusions.

Lines 294-296: NaNO3 gives a different NO+/NO2+ ratio than does ammonium nitrate. Please comment on how this could impact the interpretation of these results.

Line 299: The average oxidation state does not look all that much different to me during the organic rich episode. Perhaps there is slightly less diurnal variability which results in an average state that is more oxidized? Please discuss further.

Lines 350-360: Please see previous comment regarding NO+/NO2+ ratio. It is very difficult to judge correlation between ions from Figure S10 due to the amount of data included. Please consider showing only the time period in question.

Lines 360-363: It seems to me premature to “confirm” that the C5H7NO3+ signal is due to organonitrates in this data given the possible issues with AMS NO/NO2.

Lines 411-420: The diurnal cycle of LV-OOA1 is difficult to see with the y-axis range given in Fig. S4. I cannot see that there are 2 peaks.

Sect 3.4: More information needs to be provided on the AMS PMF results (supplement is ok). Specifically, why were 5 factors and not 4 chosen? There is significant similarity in the three LV-OOA signals and LV-OOA3 doesn’t seem to have many distinguishing features.

Line 453: I don’t understand what is meant by “with/without biogenic emissions” for test 1. Are the biogenic emissions included or are they not?

Hennigan, C. J., Izumi, J., Sullivan, A. P., Weber, R. J. and Nenes, A.: A critical evaluation of proxy methods used to estimate the acidity of atmospheric particles, Atmos Chem Phys, 15(5), 2775–2790, doi:10.5194/acp-15-2775-2015, 2015.

Peck, J., Gonzalez, L. A., Williams, L. R., Xu, W., Croteau, P. L., Timko, M. T., Jayne, J. T., Worsnop, D. R., Miake-Lye, R. C. and Smith, K. A.: Development of an aerosol mass spectrometer lens system for PM2.5, Aerosol Sci. Technol., 50(8), 781–789, doi:10.1080/02786826.2016.1190444, 2016.


Figure 2 caption: Can you expand on what is meant by “relatively large” and what the implications of this uncertainty is for the data interpretation.
Figure 7: Please consider using shading to highlight the organic peaks of interest. It will make it easier for the reader to move between the text and the figure.

Congratulations!