DataStreme Activity 10A:

THE MIDLATITUDE CYCLONE

Do Now:

  1. Print this file.
  2. Print the Monday Image 1, Image 2 and Image 3 Files.
  3. Print (when available) the Tuesday, 13 November 2001, Daily Summary File.

To Do Activity:

  1. Read Chapter 10 in STUDY GUIDE, Part A: Narrative.
    Note: Figure 10.8a is missing the cold front symbol. See Fig. 10.8b.
  2. Go to STUDY GUIDE, Part B: Applications. Start Activity 10A.
  3. Return here (Monday Activity A File) when told to do so.

Go To STUDY GUIDE - Activity 10A Now


WELCOME BACK: Procedure continued from STUDY GUIDE.

  1. The end of last week saw a storm system develop and move across the northern tier of states. The storm followed the path of several recent ones along the path of the jet stream which has remained somewhat far to the north for this time of year. For details consult the Monday, 12 November, Daily Weather Summary.

    Image 1 is the surface weather map for 12Z 08 NOV 2001, Thursday morning. The low pressure center was located at the meeting of Lakes Superior, Michigan, and Huron. A cold front curved southwestward from the Low through Texas to Arizona and back up to Wyoming. A warm front stretched southeastward from the low pressure center to southern Pennsylvania before becoming a stationary front to Delaware.

    The pattern of winds in the region around the low-pressure center was [(clockwise) (counterclockwise)] and [(outward) (inward)].

  2. Temperatures at stations to the west ("behind") the cold front from Wisconsin to north Texas were generally [(about the same as or slightly cooler) (dramatically colder)] than the temperatures to the south and east of the front. However, dewpoints west of the front were generally 10 to 20 degrees [(lower) (higher)] than those to the east and south.

    Wind directions behind the cold front were generally from the [(north or northwest) (south or southwest)]. Wind directions ahead of the cold front were generally from the [(north or northwest) (southeast to southwest)].

  3. At stations immediately to the southwest of ("behind") the warm front, temperatures were generally [(warmer) (cooler)] and dewpoints were [(higher) (lower)] than stations to the northeast ("ahead of") of the front.

  4. High pressure centers, denoted by the bold Hs, were located to the [(east) (south) (west) (all of these locations)] of the storm's low pressure center. The Hs were associated with air masses that were separated by the fronts.

    The warm front separated cool, dry air ahead of the front from [(warmer, more humid) (cooler, drier)] air behind it. The cold front separated slightly warmer, humid air ahead of the front from [(cooler, drier) (much warmer, more humid)] air behind it.

  5. The pressure gradient pattern associated with the storm system and the air masses is stronger across [(Alabama) (Wisconsin)]. The highest wind speeds are found in the [(western Great Lakes) (Gulf Coast)] states. These positions [(are) (are not)] consistent with the relationship expected between spacing of isobars and wind speeds.

  6. Image 2 is the the map of conditions in the middle troposphere at 500 mb for 12Z 08 NOV 2001, the same time as the Image 1 surface map. The flow pattern at 500 mb showed a small trough to the [(west) (east)] of the position of the surface Low. At this level higher wind speeds were in a band across the [(northern) (southern)] tier of states. The contours were also more closely spaced over the [(northern) (southern)] tier of states.

  7. Storm systems tend to follow the mid-tropospheric winds at 500 mb. The direction of wind flow at 500 mb over the western Great Lakes (the surface Low position) indicates the storm system would move toward the [(east) (south)].

  8. Image 3 is the surface weather map for 00Z 09 NOV 2001, Thursday evening, twelve hours later than Image 1. The center of the Low is located just northeast of Lake Ontario. Compare the Image 1 and 3 surface maps. The center of low pressure has moved to the [(east) (south)] over the 12-hour period between the Image 1 surface map position and this Image 3 position.

  9. In the twelve-hour interval, the cold front generally moved toward the [(southeast) (northwest)] while the warm front moved toward the [(northeast) (southeast)]. In general, the [(warm) (cold)] front moved the greater distance during this time period. The storm system is about to form an occluded front in New York State.

    Specifically note St. Louis, the temperature and dewpoint went from 56 and 47 degrees Fahrenheit at 12Z to _______ °F and _______ °F at 00Z, respectively. The wind direction went from southwest to [(southwest) (northwest)] with the passing of the cold front.

  10. Precipitation, as shown by radar echoes, was located mainly [(ahead of) (behind)] the cold front. This is somewhat unusual, but explainable with more detailed maps and charts than those presented here. The most intense thunderstorms were located from Colorado to Oklahoma during this period, more the result of upper atmospheric conditions than the southern portion of the cold front.

The NOAA weather radio as well as the DataStreme "State Surface Data - Text" are excellent ways you and your students can keep track of hourly weather conditions that show changes as storms with their fronts approach and cross your location. Note how these conditions change and fit the general pattern expected with passing wave cyclones. NOAA radio is particularly valuable when severe weather threatens your area as most weather radios are equipped with warning alarms that can be triggered by the National Weather Service when conditions warrant. (You can track hourly weather conditions using a blank meteogram from the DataStreme homepage, under Extras, "Blank Metgram".)


Hold this activity until you have completed all applications for this week. Instructions for faxing your LIT mentor will appear at the end of this week's Activity B.


Notice: Participants are reminded that Plans of Action are to be formulated and taken to the final course meeting.

YOUR PLAN OF ACTION:

Each DataStreme course participant is asked to develop a plan of action describing how she/he intends to promote weather education and the classroom use of electronically-delivered environmental data following completion of the course.

We ask you to prepare such a Plan of Action and submit the Plan to your LIT leader at the final course meeting. Be prepared to informally discuss your plans at the meeting. The plan should be no more than a page or two in length.

Keep in mind when preparing the plan that the DataStreme Project is an NSF-funded Teacher Enhancement project. Its purpose is to assist you, as teachers, to help other teachers. The major goal of the Project is to work collegially with teachers who become weather education resource persons for other teachers in their home schools. Your participation in the DataStreme distance-learning course is intended to be the first step in this process.

The plan can simply be a list of ways in which you intend to peer train and assist other teachers to employ weather topics or electronically-delivered weather information and data in student learning experiences. Think of current weather and the meteorological data stream as vehicles for learning across the curriculum (not just for science).

As you develop your plan of action, we want you to know that you will be given multiple copies of a teacher’s guide entitled Today’s Weather at the final course group meeting. It is intended for peer training purposes and contains adaptations of Chapter 1 of the DataStreme Study Guide, Part A: Narrative and 4 activities from the Study Guide, Part B: Applications dealing with drawing isotherms, drawing isobars, using the “hand-twist” model, and interpreting a surface weather map. The 28-page teacher’s guide is intended to be given to the teachers you peer train.

Start your plan of action by listing those actions you have already undertaken or have underway as the result of DataStreme participation. We also ask that you consider including in your plan those actions that would employ products from the DataStreme Homepage to demonstrate to fellow teachers, school administrators, school boards, and community leaders the value of providing Information Age learning experiences to children.


Return to DataStreme Homepage

URL: datastreme/learn/a_act.html
©Copyright, 2001, American Meteorological Society