• Bergeron, T., 1937: On the physics of fronts. Bull. Amer. Meteor. Soc., 18, 265275.

  • Bond, N. A., and R. G. Fleagle, 1985: Structure of a cold front over the ocean. Quart. J. Roy. Meteor. Soc., 111, 739759, https://doi.org/10.1002/qj.49711146905.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Bond, N. A., and M. A. Shapiro, 1991: Research aircraft observations of the mesoscale and microscale structure of a cold front over the eastern Pacific Ocean. Mon. Wea. Rev., 119, 30803094, https://doi.org/10.1175/1520-0493(1991)119<3080:RAOOTM>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Browning, K. A., 1986: Conceptual models of precipitation systems. Wea. Forecasting, 1, 2341, https://doi.org/10.1175/1520-0434(1986)001<0023:CMOPS>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Browning, K. A., and T. W. Harrold, 1970: Air motion and precipitation growth at a cold front. Quart. J. Roy. Meteor. Soc., 96, 369389, https://doi.org/10.1002/qj.49709640903.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Browning, K. A., and G. A. Monk, 1982: A simple model for the synoptic analysis of cold fronts. Quart. J. Roy. Meteor. Soc., 108, 435452, https://doi.org/10.1002/qj.49710845609.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Geerts, B., R. Damiani, and S. Haimov, 2006: Finescale vertical structure of a cold front as revealed by an airborne Doppler radar. Mon. Wea. Rev., 134, 251271, https://doi.org/10.1175/MWR3056.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hewson, T. D., 1998: Objective fronts. Meteor. Appl., 5, 3765, https://doi.org/10.1017/S1350482798000553.

  • Hobbs, P. V., and K. R. Biswas, 1979: The cellular structure of narrow cold-frontal rainbands. Quart. J. Roy. Meteor. Soc., 105, 723727, https://doi.org/10.1002/qj.49710544516.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hobbs, P. V., and P. O. G. Persson, 1982: The mesoscale and microscale structure and organization of clouds and precipitation in midlatitude cyclones. Part V: The substructure of narrow cold-frontal rainbands. J. Atmos. Sci., 39, 280295, https://doi.org/10.1175/1520-0469(1982)039<0280:TMAMSA>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hope, P., and Coauthors, 2014: A comparison of automated methods of front recognition for climate studies: A case study in southwest Western Australia. Mon. Wea. Rev., 142, 343363, https://doi.org/10.1175/MWR-D-12-00252.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Houze, R. A., Jr., and P. V. Hobbs, 1982: Organization and structure of precipitating cloud systems. Advances in Geophysics, Vol. 24, Academic Press, 225315, https://doi.org/10.1016/S0065-2687(08)60521-X.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hutchinson, T. A., and H. B. Bluestein, 1998: Prefrontal wind-shift lines in the plains of the United States. Mon. Wea. Rev., 126, 141166, https://doi.org/10.1175/1520-0493(1998)126<0141:PWSLIT>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • James, P. K., and K. A. Browning, 1979: Mesoscale structure of line convection at surface cold fronts. Quart. J. Roy. Meteor. Soc., 105, 371382, https://doi.org/10.1002/qj.49710544404.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Jorgensen, D. P., Z. Pu, P. O. G. Persson, and W.-K. Tao, 2003: Variations associated with cores and gaps of a Pacific narrow cold frontal rainband. Mon. Wea. Rev., 131, 27052729, https://doi.org/10.1175/1520-0493(2003)131<2705:VAWCAG>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Knight, D. J., and P. V. Hobbs, 1988: The mesoscale and microscale structure and organization of clouds and precipitation in midlatitude cyclones. Part XV: A numerical modeling study of frontogenesis and cold-frontal rainbands. J. Atmos. Sci., 45, 915931, https://doi.org/10.1175/1520-0469(1988)045<0915:TMAMSA>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Koch, S. E., 1984: The role of an apparent mesoscale frontogenetic circulation in squall line initiation. Mon. Wea. Rev., 112, 20902111, https://doi.org/10.1175/1520-0493(1984)112<2090:TROAAM>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Koch, S. E., and W. L. Clark, 1999: A nonclassical cold front observed during COPS-91: Frontal structure and the process of severe storm initiation. J. Atmos. Sci., 56, 28622890, https://doi.org/10.1175/1520-0469(1999)056<2862:ANCFOD>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Mass, C. F., and D. M. Schultz, 1993: The structure and evolution of a simulated midlatitude cyclone over land. Mon. Wea. Rev., 121, 889917, https://doi.org/10.1175/1520-0493(1993)121<0889:TSAEOA>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Miles, M. K., 1962: Wind, temperature and humidity distribution at some cold fronts over SE. England. Quart. J. Roy. Meteor. Soc., 88, 286300, https://doi.org/10.1002/qj.49708837708.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Mulqueen, K. C., and D. M. Schultz, 2015: Non-classic extratropical cyclones on Met Office sea-level pressure charts: Double cold and warm fronts. Weather, 70, 100105, https://doi.org/10.1002/wea.2463.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Naud, C. M., D. J. Posselt, and S. C. van den Heever, 2015: A CloudSatCALIPSO view of cloud and precipitation properties across cold fronts over the global oceans. J. Climate, 28, 67436762, https://doi.org/10.1175/JCLI-D-15-0052.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Norris, J., G. Vaughan, and D. M. Schultz, 2017: Precipitation cores along a narrow cold-frontal rainband in idealized baroclinic waves. Mon. Wea. Rev., 145, 29712992, https://doi.org/10.1175/MWR-D-16-0409.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Sanders, F., 1955: An investigation of the structure and dynamics of an intense surface frontal zone. J. Meteor., 12, 542552, https://doi.org/10.1175/1520-0469(1955)012<0542:AIOTSA>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Sansom, H. W., 1951: A study of cold fronts over the British Isles. Quart. J. Roy. Meteor. Soc., 77, 96120, https://doi.org/10.1002/qj.49707733111.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Schemm, S., I. Rudeva, and I. Simmonds, 2015: Extratropical fronts in the lower troposphere—Global perspectives obtained from two automated methods. Quart. J. Roy. Meteor. Soc., 141, 16861698, https://doi.org/10.1002/qj.2471.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Schoenberger, L. M., 1984: Doppler radar observation of a land-breeze cold front. Mon. Wea. Rev., 112, 24552464, https://doi.org/10.1175/1520-0493(1984)112<2455:DROOAL>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Schultz, D. M., 2004: Cold fronts with and without prefrontal wind shifts in the central United States. Mon. Wea. Rev., 132, 20402053, https://doi.org/10.1175/1520-0493(2004)132<2040:CFWAWP>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Schultz, D. M., 2005: A review of cold fronts with prefrontal troughs and wind shifts. Mon. Wea. Rev., 133, 24492472, https://doi.org/10.1175/MWR2987.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Schultz, D. M., and C. F. Mass, 1993: The occlusion process in a midlatitude cyclone over land. Mon. Wea. Rev., 121, 918940, https://doi.org/10.1175/1520-0493(1993)121<0918:TOPIAM>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Schultz, D. M., and G. Vaughan, 2011: Occluded fronts and the occlusion process: A fresh look at conventional wisdom. Bull. Amer. Meteor. Soc.,92, 443466, https://doi.org/10.1175/2010BAMS3057.1.

    • Crossref
    • Export Citation
  • Schultz, D. M., B. Antonescu, and A. Chiariello, 2014: Searching for the elusive cold-type occluded front. Mon. Wea. Rev., 142, 25652570, https://doi.org/10.1175/MWR-D-14-00003.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Schwerdtfeger, W., and N. D. Strommen, 1964: Structure of a cold front near the center of an extratropical depression. Mon. Wea. Rev., 92, 523531, https://doi.org/10.1175/1520-0493(1964)092<0523:SOACFN>2.3.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Seitter, K. L., and H. S. Muench, 1985: Observation of a cold front with rope cloud. Mon. Wea. Rev., 113, 840848, https://doi.org/10.1175/1520-0493(1985)113<0840:OOACFW>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Shapiro, M. A., 1984: Meteorological tower measurements of a surface cold front. Mon. Wea. Rev., 112, 16341639, https://doi.org/10.1175/1520-0493(1984)112<1634:MTMOAS>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Simmonds, I., K. Keay, and J. A. T. Bye, 2012: Identification and climatology of Southern Hemisphere mobile fronts in a modern reanalysis. J. Climate, 25, 19451962, https://doi.org/10.1175/JCLI-D-11-00100.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Young, M. V., G. A. Monk, and K. A. Browning, 1987: Interpretation of satellite imagery of a rapidly deepening cyclone. Quart. J. Roy. Meteor. Soc., 113, 10891115, https://doi.org/10.1002/qj.49711347803.

    • Crossref
    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 28 28 18
PDF Downloads 5 5 4

Comments on “A CloudSat–CALIPSO View of Cloud and Precipitation Properties across Cold Fronts over the Global Oceans”

View More View Less
  • 1 Centre for Atmospheric Science, School of Earth and Environmental Sciences, University of Manchester, Manchester, United Kingdom
© Get Permissions
Full access

Abstract

Naud et al. constructed satellite-based composite analyses of clouds and precipitation across cold fronts. However, their approach does not exclude occluded fronts, does not separate anafronts from katafronts, does not separate frontlike phenomena primarily identified by thermal gradients from those primarily identified by wind changes, and smooths over alongfront variability. By lumping these disparate frontal structures together, the front-centered composite cross sections reveal forward-sloping structures and weak gradients across them, raising questions about how to interpret their composite cross sections.

This article is licensed under a Creative Commons Attribution 4.0 license (http://creativecommons.org/licenses/by/4.0/).

© 2018 American Meteorological Society.

Corresponding author: Prof. David M. Schultz, david.schultz@manchester.ac.uk

The original article that was the subject of this comment/reply can be found at http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-11-00100.1.

Abstract

Naud et al. constructed satellite-based composite analyses of clouds and precipitation across cold fronts. However, their approach does not exclude occluded fronts, does not separate anafronts from katafronts, does not separate frontlike phenomena primarily identified by thermal gradients from those primarily identified by wind changes, and smooths over alongfront variability. By lumping these disparate frontal structures together, the front-centered composite cross sections reveal forward-sloping structures and weak gradients across them, raising questions about how to interpret their composite cross sections.

This article is licensed under a Creative Commons Attribution 4.0 license (http://creativecommons.org/licenses/by/4.0/).

© 2018 American Meteorological Society.

Corresponding author: Prof. David M. Schultz, david.schultz@manchester.ac.uk

The original article that was the subject of this comment/reply can be found at http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-11-00100.1.

1. Introduction

Naud et al. (2015) describe the cloud and precipitation structure of cold fronts over the global oceans from satellites using CloudSat radar data, CALIPSO lidar data, and MERRA reanalyses for temperature and wind. Using a set of automated approaches, more than 30 000 fronts over the global oceans within 30°–60°N and 30°–60°S over a 4-yr period were composited to produce cross sections of various properties across the fronts. In this comment, concerns are raised about the approaches used to produce these mean cross sections and how to interpret the resulting cross sections.

2. Concerns

Four concerns are raised that pertain to the frontal structures going into the composites.

  1. Naud et al. (2015) state that their study is about cold fronts, but an unspecified number of occluded fronts are included in their composite. “Because we could not differentiate cold and occluded fronts objectively, occluded fronts may be included in our database” (p. 6745). No effort is made to quantify to what extent their results are contaminated by occluded fronts. The classic warm-type occluded front is characterized by a forward-sloping frontal structure, cloud pattern, and ascent, which differs from the classic rearward-sloping cold front. Because the majority of occluded fronts are of the warm type (Schultz and Mass 1993; Schultz and Vaughan 2011; Schultz et al. 2014), any occluded fronts in the sample would easily contaminate any composite cold-frontal structure.
  2. Although commonly depicted as rearward-sloping in textbooks, some cold fronts have the structure of a katafront or split cold front, a forward-sloping cloud structure formed as the dry airstream from behind the cyclone flows over the surface cold front (e.g., Bergeron 1937; Sansom 1951; Browning and Monk 1982; Browning 1986; Young et al. 1987; Mass and Schultz 1993). Katafronts tend to be observed some distance equatorward from the center of the cyclone, which is the region targeted by Naud et al. (2015). Moreover, cold fronts can possess a variety of additional different structures such as the following:
  3. Naud et al. (2015, p. 6745) produce an automated scheme using MERRA reanalyses to identify fronts. This scheme is a result of two different diagnostic approaches to identifying fronts: the thermal front parameter using potential temperature at 1 km AGL (Hewson 1998) and the 6-h change in meridional wind (Simmonds et al. 2012). Fronts identified by either approach are apparently merged into a single dataset. However, previous studies that compared the two approaches showed that they sometimes did not identify the same feature (e.g., Table 4 in Hope et al. 2014; Fig. 1 in Schemm et al. 2015). Specifically, the wind shift and temperature gradient associated with cold fronts are sometimes not coincident, as reviewed by Schultz (2005). Using two different approaches to identify fronts and compositing them risks lowering the quality of the composite.
  4. Cold fronts can show a substantial alongfront variability (e.g., Jorgensen et al. 2003; Norris et al. 2017), but the approaches employed by Naud et al. (2015) average satellite data along the cold front (pp. 6745–6746) and average MERRA output along 1000 km of the front (p. 6751). “This compositing technique does not assume a general direction of the cold fronts and averages together information anywhere along and across the cold front.” (p. 6746). Thus, any of this alongfront variability is likely eliminated when the composite is constructed.

3. Results from the compositing procedure

These concerns about how the composite is constructed affect the quality of the composite. Indeed, the composites show a number of unusual properties.

  1. The inclusion of occluded fronts in an ostensible composite of cold fronts would result in forward-sloping properties of the composite, as is shown in Naud et al.’s (2015) Figs. 1 and 8c. That 20%–30% of their fronts have a forward-sloping cloud structure is indicative of this potential contamination.
  2. That the convection lies about 300 km ahead of the cold front suggests that this might be due to some of the fronts having an elevated frontal zone (as might be the case in a warm-type occluded front or katafront), prefrontal trough or wind-shift line.
  3. Because of the different shapes and structures to the fronts that comprise the composite (i.e., occluded fronts, anafronts, katafronts), the composite will necessarily result from quite a bit of variability of cold- and occluded-frontal structures. By lumping these disparate frontal structures together, the front-centered composite cross sections smooth out any signal and reveal relatively weak gradients across them, as seen in their Figs. 3, 4, 5, 6, and 7.
For this reason, the approach by Naud et al. (2015) raises questions about how the compositing is done and whether the resulting composite is meaningful.

4. Conclusions

The remarkable variety of cold-frontal structures observed in nature, plus those from occluded fronts, are lumped together through the Naud et al. (2015) compositing approach. Thus, one cannot generalize about cold fronts in the real world through a compositing process that includes an unspecified number of occluded fronts, katafronts, and anafronts, smoothing out such an observed diversity of frontal structures and alongfront structures. As such, these issues raise questions about the best way to interpret their composite cross sections.

Acknowledgments

Partial funding for Schultz comes from the UK Natural Environment Research Council to the University of Manchester, Grants NE/I005234/1 and NE/N003918/1. I thank the two anonymous reviewers for their review of this comment.

REFERENCES

  • Bergeron, T., 1937: On the physics of fronts. Bull. Amer. Meteor. Soc., 18, 265275.

  • Bond, N. A., and R. G. Fleagle, 1985: Structure of a cold front over the ocean. Quart. J. Roy. Meteor. Soc., 111, 739759, https://doi.org/10.1002/qj.49711146905.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Bond, N. A., and M. A. Shapiro, 1991: Research aircraft observations of the mesoscale and microscale structure of a cold front over the eastern Pacific Ocean. Mon. Wea. Rev., 119, 30803094, https://doi.org/10.1175/1520-0493(1991)119<3080:RAOOTM>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Browning, K. A., 1986: Conceptual models of precipitation systems. Wea. Forecasting, 1, 2341, https://doi.org/10.1175/1520-0434(1986)001<0023:CMOPS>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Browning, K. A., and T. W. Harrold, 1970: Air motion and precipitation growth at a cold front. Quart. J. Roy. Meteor. Soc., 96, 369389, https://doi.org/10.1002/qj.49709640903.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Browning, K. A., and G. A. Monk, 1982: A simple model for the synoptic analysis of cold fronts. Quart. J. Roy. Meteor. Soc., 108, 435452, https://doi.org/10.1002/qj.49710845609.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Geerts, B., R. Damiani, and S. Haimov, 2006: Finescale vertical structure of a cold front as revealed by an airborne Doppler radar. Mon. Wea. Rev., 134, 251271, https://doi.org/10.1175/MWR3056.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hewson, T. D., 1998: Objective fronts. Meteor. Appl., 5, 3765, https://doi.org/10.1017/S1350482798000553.

  • Hobbs, P. V., and K. R. Biswas, 1979: The cellular structure of narrow cold-frontal rainbands. Quart. J. Roy. Meteor. Soc., 105, 723727, https://doi.org/10.1002/qj.49710544516.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hobbs, P. V., and P. O. G. Persson, 1982: The mesoscale and microscale structure and organization of clouds and precipitation in midlatitude cyclones. Part V: The substructure of narrow cold-frontal rainbands. J. Atmos. Sci., 39, 280295, https://doi.org/10.1175/1520-0469(1982)039<0280:TMAMSA>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hope, P., and Coauthors, 2014: A comparison of automated methods of front recognition for climate studies: A case study in southwest Western Australia. Mon. Wea. Rev., 142, 343363, https://doi.org/10.1175/MWR-D-12-00252.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Houze, R. A., Jr., and P. V. Hobbs, 1982: Organization and structure of precipitating cloud systems. Advances in Geophysics, Vol. 24, Academic Press, 225315, https://doi.org/10.1016/S0065-2687(08)60521-X.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hutchinson, T. A., and H. B. Bluestein, 1998: Prefrontal wind-shift lines in the plains of the United States. Mon. Wea. Rev., 126, 141166, https://doi.org/10.1175/1520-0493(1998)126<0141:PWSLIT>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • James, P. K., and K. A. Browning, 1979: Mesoscale structure of line convection at surface cold fronts. Quart. J. Roy. Meteor. Soc., 105, 371382, https://doi.org/10.1002/qj.49710544404.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Jorgensen, D. P., Z. Pu, P. O. G. Persson, and W.-K. Tao, 2003: Variations associated with cores and gaps of a Pacific narrow cold frontal rainband. Mon. Wea. Rev., 131, 27052729, https://doi.org/10.1175/1520-0493(2003)131<2705:VAWCAG>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Knight, D. J., and P. V. Hobbs, 1988: The mesoscale and microscale structure and organization of clouds and precipitation in midlatitude cyclones. Part XV: A numerical modeling study of frontogenesis and cold-frontal rainbands. J. Atmos. Sci., 45, 915931, https://doi.org/10.1175/1520-0469(1988)045<0915:TMAMSA>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Koch, S. E., 1984: The role of an apparent mesoscale frontogenetic circulation in squall line initiation. Mon. Wea. Rev., 112, 20902111, https://doi.org/10.1175/1520-0493(1984)112<2090:TROAAM>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Koch, S. E., and W. L. Clark, 1999: A nonclassical cold front observed during COPS-91: Frontal structure and the process of severe storm initiation. J. Atmos. Sci., 56, 28622890, https://doi.org/10.1175/1520-0469(1999)056<2862:ANCFOD>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Mass, C. F., and D. M. Schultz, 1993: The structure and evolution of a simulated midlatitude cyclone over land. Mon. Wea. Rev., 121, 889917, https://doi.org/10.1175/1520-0493(1993)121<0889:TSAEOA>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Miles, M. K., 1962: Wind, temperature and humidity distribution at some cold fronts over SE. England. Quart. J. Roy. Meteor. Soc., 88, 286300, https://doi.org/10.1002/qj.49708837708.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Mulqueen, K. C., and D. M. Schultz, 2015: Non-classic extratropical cyclones on Met Office sea-level pressure charts: Double cold and warm fronts. Weather, 70, 100105, https://doi.org/10.1002/wea.2463.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Naud, C. M., D. J. Posselt, and S. C. van den Heever, 2015: A CloudSatCALIPSO view of cloud and precipitation properties across cold fronts over the global oceans. J. Climate, 28, 67436762, https://doi.org/10.1175/JCLI-D-15-0052.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Norris, J., G. Vaughan, and D. M. Schultz, 2017: Precipitation cores along a narrow cold-frontal rainband in idealized baroclinic waves. Mon. Wea. Rev., 145, 29712992, https://doi.org/10.1175/MWR-D-16-0409.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Sanders, F., 1955: An investigation of the structure and dynamics of an intense surface frontal zone. J. Meteor., 12, 542552, https://doi.org/10.1175/1520-0469(1955)012<0542:AIOTSA>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Sansom, H. W., 1951: A study of cold fronts over the British Isles. Quart. J. Roy. Meteor. Soc., 77, 96120, https://doi.org/10.1002/qj.49707733111.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Schemm, S., I. Rudeva, and I. Simmonds, 2015: Extratropical fronts in the lower troposphere—Global perspectives obtained from two automated methods. Quart. J. Roy. Meteor. Soc., 141, 16861698, https://doi.org/10.1002/qj.2471.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Schoenberger, L. M., 1984: Doppler radar observation of a land-breeze cold front. Mon. Wea. Rev., 112, 24552464, https://doi.org/10.1175/1520-0493(1984)112<2455:DROOAL>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Schultz, D. M., 2004: Cold fronts with and without prefrontal wind shifts in the central United States. Mon. Wea. Rev., 132, 20402053, https://doi.org/10.1175/1520-0493(2004)132<2040:CFWAWP>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Schultz, D. M., 2005: A review of cold fronts with prefrontal troughs and wind shifts. Mon. Wea. Rev., 133, 24492472, https://doi.org/10.1175/MWR2987.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Schultz, D. M., and C. F. Mass, 1993: The occlusion process in a midlatitude cyclone over land. Mon. Wea. Rev., 121, 918940, https://doi.org/10.1175/1520-0493(1993)121<0918:TOPIAM>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Schultz, D. M., and G. Vaughan, 2011: Occluded fronts and the occlusion process: A fresh look at conventional wisdom. Bull. Amer. Meteor. Soc.,92, 443466, https://doi.org/10.1175/2010BAMS3057.1.

    • Crossref
    • Export Citation
  • Schultz, D. M., B. Antonescu, and A. Chiariello, 2014: Searching for the elusive cold-type occluded front. Mon. Wea. Rev., 142, 25652570, https://doi.org/10.1175/MWR-D-14-00003.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Schwerdtfeger, W., and N. D. Strommen, 1964: Structure of a cold front near the center of an extratropical depression. Mon. Wea. Rev., 92, 523531, https://doi.org/10.1175/1520-0493(1964)092<0523:SOACFN>2.3.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Seitter, K. L., and H. S. Muench, 1985: Observation of a cold front with rope cloud. Mon. Wea. Rev., 113, 840848, https://doi.org/10.1175/1520-0493(1985)113<0840:OOACFW>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Shapiro, M. A., 1984: Meteorological tower measurements of a surface cold front. Mon. Wea. Rev., 112, 16341639, https://doi.org/10.1175/1520-0493(1984)112<1634:MTMOAS>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Simmonds, I., K. Keay, and J. A. T. Bye, 2012: Identification and climatology of Southern Hemisphere mobile fronts in a modern reanalysis. J. Climate, 25, 19451962, https://doi.org/10.1175/JCLI-D-11-00100.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Young, M. V., G. A. Monk, and K. A. Browning, 1987: Interpretation of satellite imagery of a rapidly deepening cyclone. Quart. J. Roy. Meteor. Soc., 113, 10891115, https://doi.org/10.1002/qj.49711347803.

    • Crossref
    • Search Google Scholar
    • Export Citation
Save