METEO 452 Evans FA14

TROPICAL METEOROLOGY TR 2:30-3:45pm 607 Walker Instructor- Dr Jenni Evans


Tropical Meteorology (Meteo 452)    Syllabus, Fall 2014

Prof. Jenni Evans (


Tuesday/Thursday 2:30–3:45 pm  607 Walker  Fall Semester:  25 August–12 December

Office Hours

Tuesday noon – 1:30 pm and by appointment
509 Walker


* METEO 411, METEO 421


METEO 414, METEO 422


Physics of the Global Tropics and Forecasting of Tropical Cyclones

Topics covered

Atmospheric processes in the tropics; climatological distributions of mass, heat, energy, momentum, and water vapor; major seasonal features: monsoon, ITCZ; transient weather systemsL tropical cyclones (theory and forecasting), cumulus convection and mesoscale convective systems (MCS), subtropical cyclones, easterly waves, equatorial waves; interannual variability; ocean feedbacks.

In this course we build on the midlatitude synoptics and dynamics foundations you have gained in previous classes to place the tropics in the context of global weather and climate. We will spend quite a bit of time on tropical cyclones (TCs), including forecasting active storms, the role of TCs in the climate system and potential impacts of climate change.

Learning Objectives


  • Develop broad based skills in scientific problem solving;
  • Develop the ability to review and synthesize the scientific literature;
  • Demonstrate knowledge of the current theories for tropical cyclone genesis, intensification and motion;
  • Demonstrate knowledge of the role of the tropics in the general circulation;
  • Demonstrate the ability to synthesize diverse data and model sources to provide a comprehensive picture of the evolving atmospheric flow;
  • Demonstrate the ability to forecast tropical cyclone track and intensity.


  • Students can demonstrate knowledge of the structure of tropical storms and the atmospheric conditions conducive for their development and movement
  • Students can demonstrate knowledge of the techniques used to forecast the development and evolution of tropical storms
  • Students can demonstrate knowledge of the role that the tropics plays in the global general circulation
  • Students can demonstrate knowledge of tropical waves and their relationship to organized convection in the tropics and to tropical cyclogenesis
  • Students can demonstrate knowledge of major sources of tropical variability including the El Niño/Southern Oscillation and the Madden-Julian Oscillation

* Students who do not meet these prerequisites will be dis-enrolled by me during the first 10-day free add-drop period (see ), unless you have consulted with me in advance. Students who re-enroll after being dis-enrolled according to this policy are in violation of Item 15 on the Student Code of Conduct ( ).


Class Communications

  • Class-related emails must be sent through Angel. This will ensure that I see them and can respond in a timely fashion.
  • I welcome constructive feedback on the class material during semester. Feel free to come up and discuss with me or send me email. If you’d prefer, leave a note in my department mailbox. If you would like to see improvements, please make a viable suggestion for achieving that change. I will consider all feedback carefully, but may only implement some ideas.

Academic Integrity

Academic honesty is required and expected in this class. This course adopts the EMS Academic Integrity Policy . Students in this class are expected to write up their papers individually and in their own words using proper citations and to work their exam on their own. Students must not copy exam answers from another person's paper and present them as their own; students must not plagiarize text from papers written by others. Students presenting other people's work as their own will earn zero on the assignment or exam. Academic dishonesty may additionally result in an F or XF in the course.

If you are unclear on any aspect of this policy, consult me immediately.

Accommodations for students with disabilities

Penn State welcomes students with disabilities into the University's educational programs. In order to receive consideration for reasonable accommodations, you must contact the appropriate disability services office at the campus where you are officially enrolled,  participate in an intake interview, and provide documentation : . If the documentation supports your request for reasonable accommodations, your  campus’s disability services office  will provide you with an accommodation letter.

See the Office for Disability Services (ODS) web site for further information and a list of contact information for every Penn State campus .

Attendance (includes exam conflict, student health, religious observance, personal emergency)

The Penn State Class Attendance policies Attendance Policy 42-27: , Attendance Policy E-11: , and Conflict Exam Policy 44-35: are followed in this course. Students who miss class for legitimate reasons will be given a reasonable opportunity to make up missed work. Legitimate reasons for missing class include religious observance ( Religious Observance Policy: ), family emergencies, and university-approved curricular or extracurricular activities. Whenever possible, students participating in University-approved activities should submit to the instructor a Class Absence Form available from the Registrar's Office: , at least one week prior to the activity. If you are still unsure as to whether your situation is a “legitimate unavoidable” absence, talk to me in advance.

Students who become ill or sustain an injury should use their best judgment on whether or not they are well enough to attend class. According to the university Illness Verification Policy: , students with minor illness or injury (less than a week absent from class) are not required to secure the signature of medical personnel, however a student may be asked to produce a medical certificate for absences that persist for more than a week.

Students encountering serious family, health, or personal situations that result in extended absences should contact the Office of Student and Family Services for help: .

Campus emergencies (including weather delays) and personal safety alerts

Campus emergencies and personal safety alerts, including weather delays, are communicated via PSUAlert. To sign up for email notifications, register at ; see for information on how to receive campus-specific notifications via Twitter or Facebook. This information is also available on Penn State News ( http:/ ).


Class Texts (both online and both free!)

  • Introduction to Tropical Meteorology by Arlene Laing and Jenni Evans. This textbook is available free online at . To use this resource you will have to register with the UCAR/COMET program if you have not already. Use of all UCAR/COMET modules is free; registration is for tracking purposes only.
  • Style for Students Online, by Joe Schall. This all-purpose style handbook was written for college students specializing in technical fields. It is available online at . Style for Students Online  covers everything from comma usage to email, presentations to resume writing.


Scientific Journals

You will need to access scientific journals for your research papers. The Penn State libraries  have online subscriptions to a wide array of relevant journals and the EMS library  has a wealth of books (of all ages) and older journals available in physical form. LionSearch  is a searchable database for all Penn State resources. You may also request electronic copies of resources not available at Penn State through the library website.

Angel website

Important class information will be posted on the class Angel website and will be updated throughout the semester . It is your responsibility to keep up to date with all deadlines and other class arrangements and information provided there.

A suite of links is provided under the Resources tab. This list is a starting point, it is not comprehensive.



Project Expectations

Everyone experiences the weather and most people rely on weather forecasts to some degree, so they are familiar with our science of meteorology and with at least some of its practitioners. Thus, meteorologists are often the face of science to the public and so we have the opportunity to serve society as interpreters of science. While you may be specializing in any one of our options or subject areas, few of you will have the luxury – or, perhaps the desire – to stay in your original specialty.

The assignments you will master this semester are designed to help you to develop your skills at synthesizing and explaining science, data analysis and forecasting.

Your goal is to communicate your science in an effective, professional and entertaining manner .


Organization of information and clarity of presentation, ability to provide comprehensive written and oral summaries of research results (yours and others) are necessary skills for a scientist. Achievement in these areas, as well as the midterm and team forecast labs, will form the basis of your grade. You will also be evaluated on your professionalism, your participation in class and the effectiveness of your contributions to team projects.

  • No late projects will be accepted without my approval in advance of the due date . Late projects will be assessed a 5% penalty on grade for each week (or part of week) late.
  • Any makeup exams will be administered as oral exams .



  1. Preparing to be a Forecaster-(Individual, 10%)
    • Regardless of your major, every one of you will have the experience of the first day in your first job of your new career. It is critical that the first impression you make emphasizes your skills and abilities for that career. In this project, you are preparing for your first job as a forecaster in a tropical location. This project begins in the first week of class, so check the class Angel site today!
  2. Forecasting History - (Team, 10%)
    • You will be assigned to one of two teams. Each team will produce forecasts for three tropical cyclone cases. These three forecasts will differ in your resources as a forecaster: you will have access to the information available historically to forecasters in 1265, 1900 and 2014. And, your teams will be at war!
  3. Forecast Labs - (Team, 15%)
    • Forecasting labs will be done in teams. Each team will be responsible for validating their own forecasts each week and providing it to me in the required class format . Teams will have 45 minutes in class to formulate their 72-hour forecasts. Each team will be expected to explain and justify their forecast to the rest of the class in the remaining lecture time.
    • Forecast Deliverables are (1) a 72-hour track forecast [positions rounded to the closest 0.5 ° latitude/longitude]; (2) intensity [by category and to the nearest 10 knots]; and (3) whether the storm will make landfall, decay, or undergo extratropical transition. If there are no active storms, you may be tasked to forecast the likelihood of tropical cyclogenesis in the coming 72-hours.To aid in validation, forecast times should coincide with NHC standard times (12 hourly beginning at 0900 UTC); your forecasts should extend at least 72-hours from the last NHC advisory location.
  4. The Current State of Tropical Cyclone Science and Forecasting - (Teams, 25%)
    • Every four years, the World Meteorological Organisation (WMO) of the United Nations brings together tropical cyclone forecasters and researchers from around the world. The task of these professionals is to review the changes in our science over the previous four years and to make recommendations on the most promising and societally important challenges that should be tackled in the upcoming four years. You will enter into this process, reviewing the new science and drafting your own sets of recommendations.
  5. This project will include some class periods for discussion and consultation.Midterm Exam - (Individual, 15%)
    • There will be one midterm exam in this course; there will not be a final exam. The tentative date for this exam is Tuesday, November 11 . Any make-up exams will be oral exams, no exceptions.
  6. Summary Paper - (Individual, 5%)
    • Your project is to write an original  scientific paper on tropical cyclones. The paper could be about the meteorology, forecasting, climate variability, climate change, environmental impacts, water resources, planning for resilience, or any other topic centered on the science of tropical cyclones. Key aspects of this assignment are defining your topic, gathering information, synthesizing it , thinking critically to reach sound conclusions and working out how best to communicate your conclusions.
  7. Tropical Cyclones Term Paper - (Individual, 20%)
    • Your project is to write an original  scientific paper on tropical cyclones. The paper could be about the meteorology, forecasting, climate variability, climate change, environmental impacts, water resources, planning for resilience, or any other topic centered on the science of tropical cyclones. Key aspects of this assignment are defining your topic, gathering information, synthesizing it , thinking critically to reach sound conclusions and working out how best to communicate your conclusions.


Tropical Meteorology (METEO 452) Course Outline

  1. Role of the tropics in the general circulation
    Overview of the general circulation: atmosphere, ocean, monsoons
    Tropical convection
    A simple model for the Hadley Circulation
  2. Tropical Cyclone Climatology and Structure
    Genesis locations, tracks, Gray conditions
    Basic symmetric structure
    Regions of a tropical cyclone
    Balance in the core, envelope and outer storm region
  3. Tropical Cyclone Motion
    Environmental steering and the  -effect
    Fujiwhara rotation
    Effect of vertical wind shear
    Motion forecasting
  4. Tropical Cyclone Intensity Change
    Factors affecting intensity
    Maintenance of a static storm: CISK and WISHE
    Potential Intensity
    Eyewall replacement cycles
    Intensity and structure forecasting
  5. Tropical Cyclone Numerical Forecasting Tools 
    Dynamical Models (parameterization, initialization, data, cautions)
    Ensemble prediction systems
    Statistical models
  6. Extratropical Transition (ET)
    Role of trough interaction and warm advection
    Downstream influences
    Decay versus ET
    Forecast challenges and implications
  7. Large-scale tropical variability
    Walker Circulation
    Madden Julian Oscillation (MJO)
    El Niño/Southern Oscillation (ENSO)
  8. Preferred Locations for Tropical Cyclogenesis
    Subtropical Cyclones
    Easterly waves
  9. Equatorial waves
    Equatorial Rossby Waves
    Mixed Rossby-gravity Waves
    Equatorial Kelvin Waves
  10. The African Monsoon 
    Organized Convection
  11. Tropical Cyclone Intensity Change II 
    Review of WISHE
    Ocean interactions
    Potential Intensity
  12. More on Tropical Cyclone Structure (time permitting)
    Structure changes during landfall
    Vortex stability (parcel theory; Shapiro and Willoughby)
    Role of convection and its organization (polygonal eyewalls, shear)
    Spiral bands as Vortex Rossby Waves