Meteorology and Atmospheric Physics

, Volume 128, Issue 6, pp 733–750 | Cite as

Modeling studies on the formation of Hurricane Helene: the impact of GPS dropwindsondes from the NAMMA 2006 field campaign

  • Michael J. Folmer
  • Robert W. Pasken
  • Sen ChiaoEmail author
  • Jason Dunion
  • Jeffrey Halverson
Original Paper


Numerical simulations, using the weather research and forecasting (WRF) model in concert with GPS dropwindsondes released during the NASA African Monsoon Multidisciplinary Analyses 2006 Field Campaign, were conducted to provide additional insight on SAL-TC interaction. Using NCEP Final analysis datasets to initialize the WRF, a sensitivity test was performed on the assimilated (i.e., observation nudging) GPS dropwindsondes to understand the effects of individual variables (i.e., moisture, temperature, and winds) on the simulation and determine the extent of improvement when compared to available observations. The results suggested that GPS dropwindsonde temperature data provided the most significant difference in the simulated storm organization, storm strength, and synoptic environment, but all of the variables assimilated at the same time give a more representative mesoscale and synoptic picture.


Tropical Cyclone Global Forecast System West African Monsoon Tropical Depression Cape Verde Island 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The critical reviews of anonymous reviewers and the editor were very helpful. We acknowledge the suppliers of datasets utilized in this research. We wish to express our appreciation to T. Eichler and G. Chen for the suggestions for the development of this research. This research was partly supported by the National Science Foundation Grant AGS-1209296 and NASA Grant NNX15AQ02A.


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Copyright information

© Springer-Verlag Wien 2016

Authors and Affiliations

  • Michael J. Folmer
    • 1
  • Robert W. Pasken
    • 2
  • Sen Chiao
    • 3
    Email author
  • Jason Dunion
    • 4
  • Jeffrey Halverson
    • 5
  1. 1.ESSIC, University of MarylandCollege ParkUSA
  2. 2.Department of Earth and Atmospheric SciencesSaint Louis UniversitySaint LouisUSA
  3. 3.Department of Meteorology and Climate ScienceSan Jose State UniversitySan JoseUSA
  5. 5.University of Maryland, Baltimore CountyBaltimoreUSA

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