The following web-page will be used for the AOSS 440 Class Weather Discussions.  This page may also be used during individual analyses and forecasts that are made as part of our class forecasting competition.  The links that are provided have been chosen both for their completeness and their ease of writing this html code!  Numerous sources of this data exist on the web (including our own UM-Weather page). I highly encourage you to use GEMPAK/GARP in your daily analysis, as well.

Review of Current Weather Conditions

1. National Surface Map
   

   1. The weather conditions experienced in Southeast Michigan are the result of the passage of a series of mid-latitude weather systems that stretch around the middle latitudes of the Earth.  Identify the location of  the major weather systems currently located across the United States and Canada, paying particular attention to the locations of fronts, areas of precipitation, and temperature/dew point patterns and/or advection.
      
   2. Use recent surface maps and computer or web-based looping software to obtain the answers to the following questions:  (1) What are the general movement trends (direction and speed) of the major weather systems across the U.S. and Canada? (2) Pay particular attention to which of these weather features were responsible for the weather across Southeast Michigan over the past 24-48 hours.  Determine which of these weather systems are upstream of the Great Lakes and whether these features have the potential to impact our area within the next 48 hours?
   3. Data Sources: NOAA Current Surface, NOAA Surface Loop

2. National Satellite Map
   

   1. Observe areal extent of clouds associated with the major weather systems across the U.S. and Canada.
   2. Use satellite loops to determine if the areal extent of these cloud regions is growing or shrinking.
   3. Data Sources: GOES-EAST VIS, GOES-EAST IR, GOES-EAST Water Vapor

3. National Radar Map
   

   1. Observe areal extent of precipitation associated with the major weather systems across the U.S. and Canada.
   2. Are areas of precipitation stationary or transient?
   3. Are areas of precipitation changing areal coverage or intensity?
   4. Source: NOAA Aviation Weather Center

4. Climatological Maps
   

   1. Next, we begin to focus our attention on our forecast area: Southeast Michigan.  Review overnight minimum temperatures across the Great Lakes and potential regions of influence.
   2. Review yesterday's maximum temperatures across the Great Lakes and potential regions of influence.
   3. Review 24-hour precipitation totals across the Great Lakes and potential regions of influence.
   4. Review current depth of snow, which could have a large influence on max and min temps.
   5. Sources: SUNY Difax Max, SUNY Difax Min, SUNY Difax 24 Hour Precip, SUNY_Difax_Snow Cover

5. Local Conditions
   

   1. Review the conditions in Southeast Michigan over the past 24 hours, including the current conditions both locally and across the Great Lakes (include this information on your forecast worksheet):
   2. Sources: NOAA Aviation Weather Center, NCAR METARs, Unisys Detroit Meteogram and Current Conditions at Space Research Building,  NOAA-GLERL Ice Cover

6. Local Satellite and Radar (Pontiac/White Lake)
   

   1. Note areal extent of clouds and the areal extent/intensity of areas of precipitation impacting Southeast Michigan.
   2. Note changes in areal extent or intensity over past 3-6 hours.
   3. Source: NOAA Aviation Weather Center, NWSFO Pontiac/White Lake 

7. Hemispheric 300-mb Chart:
   

   1. Finally, we need to link the upper-level flow, temperature and moisture patterns with the features at the surface.  Observe location of major troughs and ridges responsible for synoptic systems on national surface map (or for areas of precipitation not necessarily associated with distinct synoptic scale low-pressure system).
   2. Analyze for potential blocking patterns.
   3. Source:  NOAA Climate Diagnostics Center

8. CONUS 500-mb Chart
   

   1. Observe location of major troughs and ridges responsible for synoptic systems on national surface map (or for areas of precipitation not necessarily associated with distinct synoptic scale low-pressure system).
   2. Observe 500-1000-mb thickness patterns for temperature advection.
   3. Observe 12-hour changes in geopotential height (for ridge/trough movement, filling/deepening).
   4. Source: Unisys, SUNY_Difax_500mb

9. CONUS 700-mb Chart
   

   1. Observe general wind flow patterns (for storm cell motion).
   2. Observe moisture field (for determination of likely advection of clouds).
   3. Source: Unisys,  SUNY_Difax_700mb

10. CONUS 850-mb Chart
    

    1. Observe temperature patterns (for max temperature and precipitation type forecasts).
    2. Observe moisture advection patterns (for inflow of moisture of potential convective activity).
    3. Source: Unisys,  SUNY_Difax_850mb

11. Skew-T Log-P/Vertical Soundings
    

    1. Observe temperature structure for significant stable/unstable layers.
    2. Observe temperature/dew point structure for significant layers of moisture (fore determination of cloud layers).
    3. Calculate/review convection potential indices.
    4. Source: UM-Weather

Forecast Discussion

During the initial phases of our class, we will primarily be using our analysis of the current conditions when making our forecasts for Southeast Michigan.  However, the following products from NOAA can be used to provide general guidance on the movement of surface features during the forecast period.  We will hold off on direct use of the numerical model and their derived products until February 2006.  These products are from the NWS Aviation Weather Center and provide the on-duty meteorologists interpretation of the different NWP models produced by NCEP.

1. Surface Analysis
2. 12 Hour Forecast
3. 24 Hour Forecast
4. 36 Hour Forecast
5. 48 Hour Forecast

MOS Data Page

The NOAA NWS Meteorological Development Lab has a series of MOS-based products that can be found at the following site:

Current MOS Products