MetEd: Meteorology Education and Training. Operated by the COMET Program

Description:
This module discusses how to apply various observational data and remote sensing tools such as satellite, METARS, soundings, profilers, radar, and model analyses to diagnose the potential for fog and/or low stratus. Various forecast tools (such as model forecast fields, forecast soundings, and BUFKIT) used to assess fog and/or low stratus potential onset, intensity, and duration are also examined. This module is part of the Distance Learning Course 1: Forecasting Fog and Low Stratus.

Objectives:
• Apply various observational data and remote sensing tools such as satellite, METARS, soundings, profilers, radar, and model analyses to diagnose the potential for fog and/or low stratus
• Apply various forecast tools such as model forecast fields, forecast soundings, and BUFKIT to assess fog and/or low stratus potential onset, intensity, and duration

Estimated time to complete: 3 h

Includes audio: no

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2003-06-28

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Description:
This module addresses the local and regional climatological considerations and presents tools and methodologies that can be used to assess whether atmospheric conditions can foster fog or low stratus development. Knowing your local climatology and assessing whether it supports favorable conditions for fog or low stratus development is an important step in the forecast process. A number of physical conditions that determine fog or stratus development are largely dictated by climatological restraints, as well as the synoptic pattern. This module is part of the Distance Learning Course 1: Forecasting Fog and Low Stratus.

Objectives:
Understand how climate data can be applied to the forecast process
• Understand the strength and limitations of the various types of climate data and their application to fog and stratus forecasting
• Demonstrate an ability to correctly apply climate data to fog and stratus forecasting

Estimated time to complete: 2 h

Includes audio: no

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2003-06-28

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Description:
This case examines an event that took place over New England and the Mid-Atlantic on 14 June 2001. As the culminating exercise for lessons 1 and 2 of the Distance Learning Aviation Course 1 (DLAC1) on Fog and Stratus Forecasting, its objectives are to 1) identify the preconditions favorable for fog or stratus development; 2) identify synoptic and local processes that influence the event; 3) assess onset time, duration, dissipation, and intensity; and 4) develop a TAF that reflects expected changes in ceiling and visibility. The module is a re-creation of several live teletraining sessions offered in 2003 as part of DLAC1.

Objectives:
• Identify the preconditions favorable for fog or stratus development
• Identify both the synoptic and local processes that will be influencing the event
• Determine the details of the forecast in terms of the onset time, the duration, and the time of dissipation, as well as the intensity of the event
• Assess how the fog or stratus event will affect ceiling and visibility
• Write a TAF forecast that reflects those changes in ceiling and visibility

Estimated time to complete: 2 h

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2004-07-15

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Description:
This case study focuses on making a forecast and writing a TAF so that it best represents the meteorological situation to aviation customers. During the exercise, the student prepares a forecast for Sioux Falls, South Dakota. As part of the Distance Learning Aviation Course 1 (DLAC1) on Fog and Stratus Forecasting, the exercise applies concepts taught in the rest of the course, with special emphasis on determining the impacts on airfield flight operations and creating a TAF that describes those impacts. The module is a re-creation of several live teletraining sessions offered in 2003 as part of DLAC1.

Objectives:
• Use model analyses, forecast products, soundings, and climatology to write a customer-friendly TAF
• Evaluate the impacts of forecasted ceiling and visibility conditions on the airfield operations
• Verify the accuracy and usefulness of your TAF

Estimated time to complete: 2 h

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2004-07-15

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Description:
This module addresses issues surrounding the direct and indirect impacts of restricted ceilings and visibilities on aviation operations and also briefly examines their impacts on ground and marine transportation. The goal is improve forecaster awareness of how their forecasts of these events affect commercial and general aviation operation. This module is part of the Distance Learning Course 1: Forecasting Fog and Low Stratus.

Objectives:
• Increase awareness of the various users of ceilings and visibility forecasts and how forecasts of these conditions impact (both positively and negatively) aviation operations within each user group
    o Improve forecaster understanding of the impacts of reduced visibility and ceilings on commercial and general aviation operations
    o Improve forecaster understanding of the impact to aviation operations from forecasts (TAFs) of reduced ceiling and visibility due to fog and low stratus
    o Provide recommendations on how and when to amend TAFs to best reflect current and forecast conditions
• Increase awareness of the need to be knowledgeable about supported airport configurations
• Increase knowledge of critical thresholds and their variations from one airport to another and one user group to another

Estimated time to complete: 1 h

Includes audio: no

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2003-06-28

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Description:
Fog frequently forms in response to dynamically forced changes in the boundary layer. This module examines dynamically forced fog in the coastal and marine environment, focusing on advection fog, steam fog, and west coast type fog. The focus of the module is on the boundary layer evolution of air parcels as they traverse trajectories over land and water. The module also examines mesoscale effects that impact the distribution of fog and low-level stratus over short distances. A general discussion of forecast products and methodologies concludes the module.

Objectives:
After completing this module, the learner should be able to do the following things:

With regard to the general features of dynamically forced fog and stratus:

• Describe the differences in boundary layer characteristics and evolution for advection, West Coast, and steam fog in a marine environment
• Describe the differences in synoptic environments for advection, West Coast, and steam fog in a marine environment
• Describe the relationship of sea surface temperature to fog formation for advection, West Coast, and steam fog in a marine environment
With regard to advection fog:
• Describe the general synoptic environment that is conducive to fog formation
• List at least 2 ways that subtropical high-pressure systems contribute to the formation of advection fog
• Describe the evolution of the boundary layer along an air parcel trajectory that leads to advection fog
• Describe how sea surface temperature changes along an air parcel trajectory that leads to advection fog
• Recall the origins of strong sea surface temperature gradients
• On a world map, identify areas prone to advection fog
• Recall the seasonality of advection fog

With regard to West Coast fog and low stratus:

• Describe the general synoptic environment that is conducive to fog formation
• List at least 2 ways that subtropical high-pressure systems contribute to the formation of West Coast fog and low stratus
• Describe the evolution of the boundary layer along an air parcel trajectory that leads to West Coast fog and low stratus
• List at least 2 ways that the boundary layer cools to saturation in a West Coast fog/stratus event.
• Recall the role of upwelling in the formation of West Coast fog and low stratus
• On a world map, identify areas prone to West Coast fog and low stratus
• Recall the seasonality of West Coast fog and low stratus
With regard to steam fog:
• Describe the general synoptic environment that is conducive to fog formation
• Describe the characteristics and evolution of the boundary layer along an air parcel trajectory that leads to steam fog
• On a world map, identify areas prone to steam fog
• Recall the seasonality of steam fog events

With regard to mesoscale influences upon dynamically forced fog:

• Describe the effects of coastal topography in fog formation
• Describe how coastal jets affect fog formation and dissipation
• Describe how sea breezes affect fog formation and dissipation
• Describe the impact of local variations in sea surface temperature on fog formation and dissipation

With regard to forecasting dynamically forced fog:

• Describe the general approach to forecasting fog
• List at least 4 critical atmospheric fields to monitor in plan view when forecasting fog
• List at least 4 critical atmospheric fields to monitor in vertical profiles when forecasting fog
• Describe the limitations of NWP models in fog forecasting

Estimated time to complete: 3 h

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2005-03-01

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Description:
This module consists of four exercises where users identify surface features, distinguish clouds from snow on the ground, and determine cloud phase using multispectral analysis. The module also includes an overview of multispectral techniques available on many operational and research polar-orbiting satellites. A page with links to real-time polar-orbiting data and information is also included.

Objectives:
• State the properties of the 1.6 micrometer channel used in feature identification
• State the properties channels in the 3.5 to 4 micrometer region in feature identification
• List the advantages and limitations of the 1.6 micrometer channel in cloud identification
• List the advantages and limitations of the 1.6 micrometer channel in identifying snow on the ground
• List the advantages and limitations of channels in the 3.5 to 4 micrometer region for cloud identification
• List the advantages and limitations of channels in the 3.5 to 4 micrometer region in identifying snow on the ground
• Apply the properties of the visible, IR Window, 1.6 micrometer, and 3.7 micrometer channels to:
o Distinguish clouds from snow on the ground
o Determine the phase (ice or water) of clouds
o Detect the presence of fog
o Distinguish open water from ice-covered areas of lakes and rivers

Estimated time to complete: 1-2 h

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2002-07-03

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Description:
This module deals with identifying the characteristics of radiation versus advection fog events, determining which process is dominating, and applying that understanding when making ceiling and visibility forecasts. A forecast approach using a decision tree is also discussed. This decision tree outlines the basic steps involved in applying a thorough forecast approach to fog and stratus events. The module is based on live teletraining sessions offered in 2003 as part of the Distance Learning Aviation Course 1 (DLAC1) on Fog and Stratus Forecasting.

Objectives:
1. Describe the differing processes that lead to radiation fog and advection fog

2. State the two key ingredients for the formation of fog or low stratus: increasing moisture in the boundary layer or decreasing boundary layer temperatures.

3. Properly identify which processes are dominating a particular fog or low stratus event. You can do this by:

• Examining the characteristics of the processes involved,
• Examining the low-level factors that are influencing the event, and
• Comparing these to the known characteristics, processes, and factors that distinguish a radiation event from an advective event.

Estimated time to complete: 2 h

Includes audio: Yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2004-07-15

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Description:
This is the second module in the Mesoscale Meteorology Primer series. This module starts with a forecast scenario that occurs during a winter radiation fog event in the Central Valley of California. After that, a conceptual section covers the physical processes of radiation fog through its life cycle. Operational sections addressing fog detection and forecasting conclude the module

Objectives:
At the end of the module you should be able to do the following things:

With Regard to the Preconditioning Environment:

• Identify key conditions and ingredients necessary for development of radiation fog
• Discriminate between large-scale low-level environments that are favorable and unfavorable for development of radiation fog
• Describe the sequence of key surface and boundary layer processes that prepare the low-level environment for development of radiation fog
• Demonstrate an understanding of how surface cooling dries the micro-boundary layer and prevents low-level condensation from being deposited onto the surface
• Rank various surface and surface cover types in terms of the relative speed with which low-level air in contact with them will reach saturation

With Regard to Initiation and Growth:

• Identify levels at which radiative cooling is most active at various stages of the fog initiation and growth process
• Demonstrate an understanding of the effects that various condensation nuclei types and concentrations have on fog formation
• Sequence the key processes and events that occur during formation of a layer of radiation fog
• Demonstrate an understanding of how the fog-top inversion is created by the fog itself
• Demonstrate an understanding of influences that heat flux from the surface have on a fog layer during its initiation and growth

With Regard to Maintenance Phase:

• Describe key processes that balance one another to allow a fog layer to maintain a relatively constant depth
• Identify conditions in and above a fog-top layer that support continued condensate production
• Identify conditions in and above a fog-top layer that restrict further deepening
• Demonstrate an understanding of the effects that various condensation nuclei types and concentrations have on fog maintenance
• Demonstrate an understanding of the effects that introduction of an overlying cloud layer have on a mature fog layer at the surface
• Demonstrate an understanding of influences that heat flux from the surface have on a mature fog layer
• Identify the typical level of a fog-top inversion
• Demonstrate an understanding of how the fog-top inversion is maintained by various processes at and above the top of the fog layer

With Regard to Dissipation Phase:

• Identify key processes that contribute to the dissipation of a fog layer
• Apply a droplet settling rate calculation to predict the time required for a given depth of fog layer to settle to the ground in the absence of any new condensate production
• Demonstrate an understanding of how radiative heating contributes to dissipation of a fog layer
• Demonstrate an understanding of how turbulent mixing contributes to dissipation of a fog layer
• Demonstrate an understanding of how changes in low-level winds can contribute to dissipation of a fog layer
• Demonstrate an understanding of how introduction of an overlying cloud layer can contribute to dissipation of a fog layer
With Regard to Detecting Fog:
• Identify surface observations that show atmospheric conditions conducive to radiation fog
• Identify soundings that show atmospheric conditions conducive to radiation fog
• Identify fog in satellite images
• Describe the limitations of infrared satellite images for detecting radiation fog

With Regard to Forecasting Fog:

• Describe the diurnal cycle of radiation fog occurrence
• Demonstrate and understanding of the strong seasonal dependence of radiation fog occurrence in at least two localities
• Describe which forecast products best show the atmospheric conditions conducive to radiation fog
• Describe the limitations of numerical forecast models in predicting radiation fog

Estimated time to complete: 2 h

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2002-02-04

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Description:
Local and mesoscale influences can make or break your fog or stratus forecast. Influences of local water bodies, terrain, vegetation, soil characteristics, and coastal features on the lower atmosphere can play a vital role in the development, duration, and intensity of these events. As part of the Distance Learning Course 1: Forecasting Fog and Low Stratus, this module examines several of these influences and discusses how they enhance or inhibit a fog or stratus event.

Objectives:
• Identify three local factors that can enhance fog or stratus development and be able to explain why
• Identify and describe the processes external to the boundary layer that influence duration, intensity, and dissipation
• Identify and describe the processes internal to the boundary layer that influence duration, intensity, and dissipation

Estimated time to complete: 2-3 h

Includes audio: no

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2003-06-28

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Description:
This module presents the physical processes and life cycle of radiation fog, including its preconditioning environment, initiation, growth, and dissipation. The processes include radiation (both solar and longwave), soil-atmosphere thermal interactions, turbulent mixing, the roles of condensation nuclei, and droplet settling. Each section includes a set of interactive questions based on the learning content presented.

Tom Dulong of the National Weather Service Center Weather Service Unit (CWSU) in Longmont, Colorado is the Principal Science Advisor for this module, and Dr. Paul Croft, Meteorology Program Coordinator for Jackson State University, provided additional scientific review and guidance.

Objectives:
The goal of this training module is to help you increase your understanding of how radiation fog forms, grows, and dissipates. Such understanding, in turn, can help you more efficiently and accurately evaluate the ability of a given atmospheric environment to generate and/or maintain radiation fog.

Performance Objectives

With Regard to the Preconditioning Environment:
• Identify key conditions and ingredients necessary for development of radiation fog
• Discriminate between large-scale low-level environments that are favorable and unfavorable for development of radiation fog
• Describe the sequence of key surface and boundary-layer processes that prepare the low-level environment for development of radiation fog
• Demonstrate an understanding of how surface cooling dries the micro-boundary layer and prevents low-level condensation from being deposited onto the surface
• Rank various surface and surface cover types in terms of the relative speed with
which low-level air in contact with them will reach saturation

With Regard to Initiation and Growth:
• Identify levels at which radiative cooling is most active at various stages of the fog initiation and growth process
• Demonstrate an understanding of the effects that various condensation nuclei types and concentrations have on fog formation
• Sequence the key processes and events that occur during formation of a layer of radiation fog
• Demonstrate an understanding of how the fog-top inversion is created by the fog itself
• Demonstrate an understanding of influences that heat flux from the surface have on a fog layer during its initiation and growth.

With Regard to Maintenance Phase:
• Describe key processes that balance one another to allow a fog layer to maintain a relatively constant depth.
• Identify conditions in and above a fog-top layer that support continued condensate production
• Identify conditions in and above a fog-top layer that restrict further deepening
• Demonstrate an understanding of the effects that various condensation nuclei types and concentrations have on fog maintenance
• Demonstrate an understanding of the effects that introduction of an overlying cloud layer have on a mature fog layer at the surface
• Demonstrate an understanding of influences that heat flux from the surface have on a mature fog layer
• Identify the typical level of a fog-top inversion
• Demonstrate an understanding of how the fog-top inversion is maintained by various processes at and above the top of the fog layer

With Regard to Dissipation Phase:
• Identify key processes that contribute to the dissipation of a fog layer
• Apply a droplet settling rate calculation to predict the time required for a given depth of fog layer to settle to the ground in the absence of any new condensate production
• Demonstrate an understanding of how radiative heating contributes to dissipation of a fog layer
• Demonstrate an understanding of how turbulent mixing contributes to dissipation of a fog layer
• Demonstrate an understanding of how changes in low-level winds can contribute to dissipation of a fog layer
• Demonstrate an understanding of how introduction of an overlying cloud layer can contribute to dissipation of a fog layer

Estimated time to complete: 1-2 h

Includes audio: yes

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 1999-12-10

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Description:
In order to assess whether a fog or stratus event is possible, you must evaluate the synoptic-scale influences that will drive the local conditions. In this module, we examine several common synoptic situations to understand the processes involved in fog or low stratus development. Most of these are forced primarily by advective or dynamic processes (although radiation does play a role). A more detailed discussion of radiation processes is contained in the Radiation Fog module. This module is part of the Distance Learning Course 1: Forecasting Fog and Low Stratus.

Objectives:
• Identify the large-scale and local conditions that support the development, maintenance, and dissipation of fog/stratus events
• Identify several synoptic regimes that can result in advection or radiation fog and the processes that contribute to fog formation, maintenance, and dissipation for each

Estimated time to complete: 2-3 h

Includes audio: no

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2003-06-28

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Description:
This is part of the Physical Processes Professional Competency Unit of the Forecasting Low-Altitude Clouds and Fog for Aviation Operations Professional Development Series. West Coast Fog discusses the climatology, physical
processes, and evolution of hot spell fogs along the U.S. West Coast.

Objectives:
The goal of this training module is to help you increase your understanding of how radiation fog forms, grows, and dissipates. Such understanding, in turn, can help you more efficiently and accurately evaluate the ability of a given atmospheric environment to generate and/or maintain radiation fog.
Performance Objectives
With Regard to Climatology
Basic Level Competencies:
• Identify coastal regions worldwide where (west coast-type) fogs occur
• For each region, state the seasons of highest and lowest frequency
With Regard to the Preconditioning Environment:
Basic Level Competencies:
• Identify typical synoptic-scale patterns associated with preconditioning processes that prepare the coastal environment for fog formation
• List low-level and sea surface conditions that are typically present prior to onset of the fog formation cycle
Advanced Level Competencies:
• Sequence key processes and events that occur during the preconditioning phase
• Demonstrate an understanding of how/why the surface inversion forms as a result of hot dry offshore winds
• Describe* how/why/where coastal upwelling occurs
With Regard to Formation:
Basic Level Competencies:
• Identify typical synoptic-scale pattern transitions associated with the formation phase
• Identify the key processes and events that occur during fog formation.
Advanced Level Competencies:
• Apply rules that describe the relationships between SST, inversion base, LCL, MCL, etc.
With Regard to Growth and Maturity:
Basic Level Competencies:
Describe the continued deepening and horizontal growth of the fog
• State the typical maximum height that the inversion can reach with cloud still extending to the surface
• Describe diurnal cycles (including stratus raising/lowering)
Advanced Level Competencies:
• Demonstrate an understanding of the roles that coastal surges can play
With Regard to Fog Dissipation and/or Stratus formation:
Basic Level Competencies:
• List processes that can result in fog dissipation (advection over land, warmer water, synoptic systems, solar radiation, the start of a new cycle)
• Identify typical synoptic-scale patterns that can destroy fog regimes in MBL
• Sequence the major events that comprise the ~15-day warm season fog cycle in this region
Advanced Level Competencies:
• Describe how the fog erodes upward to form the marine stratus regime that was present prior to fog formation
• State general rule regarding relationship between sun angle and fog dissipation through insolation
• Demonstrate an understanding of how/why dissipation occurs when the MCL reaches the base of the inversion

Estimated time to complete: 1 hr

Includes audio: no

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2000-09-29

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Description:
This module provides an overview of some of the applicable TAF Amendment and Conditional Group usage rules, as presented in the latest version of the National Weather Service Instruction 10-813 on TAF directives. It also presents a methodology for TAF writing and development that will lead to an effective and user-friendly product. The focus is on the ceiling and visibility aspects of the TAF. This module is part of the Distance Learning Course 1: Forecasting Fog and Low Stratus.

Objectives:
• Develop an understanding and appreciation for how TAF construction (intelligent vs. excessive use of TEMPO and PROB groups) may impact your aviation customers
• Develop skills in writing an effective “practical” TAF that provides an improved forecast of expected flight category changes, while maintaining a customer-friendly format. Compare effective vs. poor TAF structures for a given scenario
• Develop concise TAFs with sparing use of change or conditional groups such as TEMPO and PROB, as we’ll practice in two small case exercises

Estimated time to complete: 2 h

Includes audio: no

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2003-06-28

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Description:
Para evaluar si es posible que se produzca un episodio de niebla o estratos, debemos evaluar los factores de escala sinóptica que determinan las condiciones locales. Este módulo examina varias situaciones sinópticas comunes con el fin de comprender los procesos involucrados en la formación de niebla o estratos bajos. La mayoría de ellos son forzados principalmente por procesos advectivos o dinámicos (aunque la radiación también influye en este proceso). Encontrará un tratamiento más a fondo de los procesos radiativos en el módulo sobre niebla de radiación titulado Radiation Fog. Este módulo forma parte del curso de educación a distancia sobre aviación (Distance Learning Aviation Course 1, o DLAC1) sobre el pronóstico de nieblas y estratos bajos.

Estimated time to complete: 2-3 h

Includes audio: no

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

Last published on: 2006-07-28

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Description:
En este módulo se comparan las características de los episodios de niebla de radiación y de advección con el fin de determinar cuál de dichos procesos domina y aplicar esos conocimientos a la preparación de pronósticos de techos de nubes y visibilidad. También se presenta un enfoque de pronóstico mediante un árbol de decisión. Dicho árbol de decisión describe los pasos básicos involucrados en la aplicación de un enfoque de pronóstico riguroso a los episodios de niebla y estratos. El módulo se basa en las sesiones de educación a distancia que se ofrecieron en vivo en el año 2003 como parte del curso de educación a distancia sobre aviación (Distance Learning Aviation Course 1, o DLAC1) sobre el pronóstico de nieblas y estratos.

Objectives:

• Describir los distintos procesos que llevan a la formación de las nieblas de radiación y de advección


• Describir los dos elementos esenciales para la formación de niebla o nubes estratos bajas: aumento de la humedad en la capa límite planetaria o disminución de las temperaturas en la capa límite planetaria.


• Identificar adecuadamente los procesos que dominan en un determinado episodio de niebla o estratos bajos. Con ese fin podemos:


• examinar las características de los procesos involucrados


• examinar los factores de los niveles inferiores que influyen en el episodio


• comparar esos factores con las características, los procesos y los factores conocidos que distinguen los episodios de niebla de radiación de los de niebla de advección

Estimated time to complete: 30 min

Includes audio: no

Required plug-ins:   Flash RealPlayer Java Adobe® Reader®
 * Plug-in information

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