AWOC Instructional Component

IC Winter 5:   Precipitation Forcing Mechanisms and Associated Diagnosis of Winter Weather Systems

 

General Information

Estimated IC Completion Time
3 hours, 35 min.
Description
 This instructional component features 7 lessons about precipitation formation processes. The first 5 lessons describe precipitation formation processes that are produced by internally produced atmospheric forcing. The last two lessons cover precipitation forcing mechanisms produced by external means such as topographic lifting and diabatic heating (e.g., lake effect). IC5 is an important prerequisite for IC6, Synoptic/Mesoscale Forecasting of Winter Precipitation Type and Amount, by providing information on the precipitation forcing mechanisms and their methods of diagnosis. IC6 uses the information in IC5 while introducing precipitation forecast techniques. You will see other references to IC5 in IC7's lessons 1 and 4.
Testing Procedures
Testing for Instructional Components (IC) lessons is provided to the student using the NWS Learning Management System (LMS). If testing is required, the test must be successfully completed in order to complete the lessons. A score of at least 70% on the exam is required to successfully complete each lesson.

Lessons
Lesson 1:

Diagnosing Synoptic Scale Internal Forcing: Using Potential Vorticity in Operations

Description
 This lesson shows you the benefits of using Potential Vorticity to help you diagnose vertical motions induced by short-wave troughs in the mid- to upper-troposphere. The author, Phil Schumacher, SOO NWS FSD, shows you how to use tropopause pressure maps to infer vertical motion using models whose resolution precludes you to use Q-vectors.
Estimated Lesson Completion Time
 40 min. Module Type
Articulate Presenter Module
Resources
Exercises
IC5.1 job sheet (80 MB PDF file requires Adobe Acrobat)
Review Sheets & Hand Outs
IC 5.1 student handout (80 MB PDF file requires Adobe Acrobat)
Lesson Links
NOAA employees should access this module via the NWS Learning Center as they will need to complete the exam and survey in the LMS to receive credit for completion. All others wishing to take this lesson should use the follow link(s):

IC 5.1: Using Potential Vorticity in Operations

Lesson 2:

Diagnosing Mesoscale Internal Forcing: Frontogenesis

Description
 We certainly cannot have a winter weather warning course without a lesson on frontogenesis. Phil Schumacher (SOO NWS FSD) and Dr. Dave Schultz (Research Scientist at CIMMS/NSSL) provide information on frontogenesis starting with some theory and then application to a few cases. This is an important lesson that may help clarify your understanding of this important precipitation forcing mechanism.
Estimated Lesson Completion Time
 25 min. Module Type
Articulate Presenter Module
Resources
Exercises
IC5.2 job sheet (80 MB PDF file requires Adobe Acrobat)
Review Sheets & Hand Outs
IC 5.2 student handout (80 MB PDF file requires Adobe Acrobat)
Lesson Links
NOAA employees should access this module via the NWS Learning Center as they will need to complete the exam and survey in the LMS to receive credit for completion. All others wishing to take this lesson should use the follow link(s):

IC 5.2: Diagnosing Mesoscale Internal Forcing: Frontogenesis

Lesson 3:

The Effect of Stability on the Response of internal forcing in the Atmosphere
Description
 Stability modulates how the atmosphere responds to precipitation forcing. However, the various combinations of inertial and gravitational stability that the atmosphere creates can often be confusing. This lesson provides you an understanding of how inertial and gravitational stability can combine to yield slantwise instability, and the proper methods to diagnose stability. Phil Schumacher and Dave Schultz team up again to help firm up your ideas on atmospheric stability.
Estimated Lesson Completion Time
 35 min. Module Type
Articulate Presenter Module
Resources
Exercises
IC5.3 job sheet (80 MB PDF file requires Adobe Acrobat)
Review Sheets & Hand Outs
IC 5.3 student handout (80 MB PDF file requires Adobe Acrobat)
Lesson Links
NOAA employees should access this module via the NWS Learning Center as they will need to complete the exam and survey in the LMS to receive credit for completion. All others wishing to take this lesson should use the follow link(s):

IC 5.3: The Effect of Stability on the Response of Internal Forcing in the Atmosphere

Lesson 4:

Examples of Frontal Precipitation Bands
Description
 While the theory on frontogenesis was provided to you in lesson 2, Mike Evans, SOO NWS BGM, takes that theory and shows you how frontogenesis manifests itself in a variety of cases across the country. Be ready for an informative journey that will help you expand your working memory of how frontogenesis appears in a variety of conditions.
Estimated Lesson Completion Time
 30 min. Module Type
Articulate Presenter Module
Resources
Exercises
IC5.4 job sheet (80 MB PDF file requires Adobe Acrobat)
Review Sheets & Hand Outs
IC 5.4 student handout (80 MB PDF file requires Adobe Acrobat)
Lesson Links
NOAA employees should access this module via the NWS Learning Center as they will need to complete the exam and survey in the LMS to receive credit for completion. All others wishing to take this lesson should use the follow link(s):

IC 5.4: Examples of Frontal Precipitation Bands

Lesson 5:

Structure of Trowals

Description
 Even though the concept of a TROWAL is not new, it has gained favor recently because it provides a good explanation for observed precipitation patterns in extratropical cyclones. Dr. Pat Market (Univ. of Missouri, Columbia) helps explain how fundamental precipitation forcing mechanisms manifest themselves in a TROWAL. Dr. Market also shows you several ways to diagnose TROWALS, each diagnosis method being better than the previous.
Estimated Lesson Completion Time
 30 min. Module Type
Articulate Presenter Module
Resources
Exercises
IC5.5 job sheet (80 MB PDF file requires Adobe Acrobat)
Review Sheets & Hand Outs
IC 5.5 student handout (80 MB PDF file requires Adobe Acrobat)
Lesson Links
NOAA employees should access this module via the NWS Learning Center as they will need to complete the exam and survey in the LMS to receive credit for completion. All others wishing to take this lesson should use the follow link(s):

IC 5.5: Structure of Trowals

Lesson 6:

Cool-Season Orographic Precipitation processes and Prediction

Description
 Here is a lesson on topographic forcing of precipitation authored by Dr. Mike Meyers (SOO NWS GJT), Dr. Doug Wesley (COMET), and Dr. W. James Steenburgh (Univ. of Utah). You will see three sections: the first covering the dynamics and microphysics representative of all orographic precipitation, the second dealing with the behavior of topographic precipitation for several mountain ranges in the western US, and the final section on methods and tools for forecasting orographic precipitation. Parts of this lesson are contributions from the COMET module titled "Dynamics and Microphysics of Cool-Season Orographic Storms" while other parts represent new findings. This is an optional lesson but if you do have even the most subtle orographic effects, you will find this lesson valuable.
Estimated Lesson Completion Time
 50 min. Module Type
Articulate Presenter Module
Resources
Exercises
IC5 lesson 6 job sheet
Review Sheets & Hand Outs
IC 5.6 student handout (80 MB PDF file requires Adobe Acrobat)
Lesson Links
NOAA employees should access this module via the NWS Learning Center as they will need to complete the exam and survey in the LMS to receive credit for completion. All others wishing to take this lesson should use the follow link(s):

IC 5.6: Cool-Season Orographic Precipitation Processes and Prediction

Lesson 7:

Lake Effects

Description
 Tom Niziol (MIC, NWS BUF) delivers an entertaining and informative overview of lake effects, or more generally, precipitation forcing through localized diabatic heating. You will learn many aspects of lake effect, from quantifying temperature and moisture modification by using the Philip's equations within BUFKIT to understanding enlarged band morphology using high resolution ETA model output.
Estimated Lesson Completion Time
 25 min. Module Type
Articulate Presenter Module
Resources
Exercises
IC 5 Lesson 7 job sheets.
Review Sheets & Hand Outs
IC 5.7 student handout (80 MB PDF file requires Adobe Acrobat)
Lesson Links
NOAA employees should access this module via the NWS Learning Center as they will need to complete the exam and survey in the LMS to receive credit for completion. All others wishing to take this lesson should use the follow link(s):

IC 5.7: Lake Effects

Contact

Email
Winter AWOC IC 5 Development Team.
Telephone
(405) 573-3350