AMDAR Display Change Details

24-Jan-2017 (production and beta)
Moved to the embw3 web server. As a part of this, we had to decommission the non-java IDL-based display.

17-Jan-2017 (production and beta)
Added several Chilean airports to support soundings from LATAM aircraft. Routine(s) changed: airport_info.txt.

3-Jan-2017 (production)
Downgraded the compiled code to java 1.2 so folks with OLD versions of java can run the applet.

28-Dec-2016 (production and beta)

19-Oct-2016 (production and beta)
For MADIS archive data, we now check both locations for the MADIS archive if necessary: and (in that order). Routine changed:

13-Oct-2016 (production and beta)
For archive data (older than 30 days), the location of the MADIS archive was set to This is apparently a backup site. Soon, we'll adjust things so the primary site (which is currently down) is tried first, and then this backup site. Routine changed:

12-Oct-2016 (beta)

20-July-2016 (beta)
The size of the plan-view display is now settable by an optional parameter in the page that calls the applet. Routine(s) changed: MainACARS, Welcome.cgi.

18-July-2016 (beta and production)
For restores of old data, we now link to the new MADIS archive server:

8-Feb-2016 (beta and production)

4-Jan-2015 (beta and production)
Since we've moved to a different server than, we had to change some links so that model and RAOB soundings would successfully load in the soundings window, if requested. (There were no complaints about this broken functionality in the last three weeks, so this apparently is not an often-used option.) Routine(s) changed: reply-setup.cgi.

8-Dec-2015 (production)
A special version ( has been compiled to be compatible with Java version 1.6, to be runnable on machines that haven't upgraded their java. Some browsers require you to be running the latest version of java (1.8 currently), and the Chrome browser no longer runs java at all. It is best to upgrade your java to the latest version, but if that can't be done in a timely manner, try using .

12-Nov-2015 (production)
All beta changes moved to production.

27-Oct-2015 (beta)

1-Apr-2015 (production)
All beta changes moved to production.

31-Mar-2015 (beta)

21-Oct-2014 (beta and production)

7-Mar-2014 (beta)
Color coding for EDR obs was changed to be a little more discriminatory. Also, the display priority was set to favor displaying high-EDR events when EDR is displayed. Routines changed: MainACARS, EdrOb.

13-July-2011 (beta and production)
When the sounding window comes up with an aircraft sounding and you click on the 'Load other Sdgs' button, the load window that comes up was preset to load '0' hours. This had to be manually changed to load 1 or more hours for a model sounding to be loaded. (Previously, 0 hours would load 1 model sounding, but this behavior was changed on the side a while back.) Now the default is to load '1' hours. Routines changed: ACARSSoundingDriver, sdg.SoundingPanel.

16-March-2011 (beta and production)
For archival data (data more than 30 days old), we now use the MADIS anonymous FTP site ( to retrieve data back to July 2001. Previously we'd been using a restricted site. But since all archival data are freely available, there's no reason to do so. Routines changed:

4-May-2010 (beta and production)

7-April-2010 (beta and production)

25-Jan-2010 (beta and production)

21-Oct-2009 (beta) -- moved to production at an unknown date
WVSS-II Quality flags higher than 3 are now passed through for display in the 'track' window accessed by right-clicking on a flight track. For WVSS-II data with bad QC (flag > 3), dewpoint is set to missing, but the "downlinked RH" is reported in the flight-track window, along with the QC flag. Routines changed: VaporOb.

8-Oct-2009 (production and beta)
Two changes made to the underlying AMDAR data processing:

7-Oct-2009 (production and beta)
Fixed a bug that caused the select frame not to work until the user had clicked show all. Routines changed: SelectFrame.

4-Sep-2009 (production and beta)
All data more than 48h old (including both operational and research TAMDAR data, and QC'd NCAR EDR data) are fully available to authorized users of real-time data on the real-time page (, just as they are to all users on the demo page ( Note that, previous to 12 Aug 2009, the definition of TAM rsch and TAM_OPS data (see 12-Aug-2009 change below) was different. All TAMDAR data previous to 12-Aug-2009 will show up as TAM rsch. ALL available TAMDAR data can always be displayed using the all TAMDAR option in the Select window. Routines changed: getACARS.cgi.

12-Aug-2009 (production and beta)

27-April-2009 (production and beta)

23-Oct-2008 (production and beta)
Additional airports added: Iron Mtn., MI; Pensacola, FL; Lake Charles, LA; Wilmington, NC; Ithaca, NY; Odessa, TX; Laredo, TX; Columbia, MO; Dubuque, IA; Escanaba, MI; Sault Ste. Marie, ON/CN.

7-September-2008 (production and beta)
TAMDAR/PenAir data now available to the U.S. Government (with the same restrictions as TAMDAR/Mesaba data). Routine changed: ACARSLoader

29-August-2008 (production and beta)

9-June-2008 (production and beta)
New airports added, primarily in Scandanavia and the middle east.

5-May-2008 (production)
All beta changes moved to production.

3-April-2008 (beta)
Changed altitude color coding so data are only colored with the bad color (gold) when both wind and temperature are bad. Previously, data were colored bad when either wind or temperature were bad. Routine changed: MainACARS.

14-Dec-2007 (production and beta)
Kaparuk Airport (PAKU), near Prudhoe Bay, Alaska has been added. Pen Air flies into this airport several times per week.

4-Sept-2007 (production and beta)
TAMDAR data are now restricted as follows: Missing or 'bad' data are shown in gold color on the display. If you want to not see this data at all, use the 'select' window and choose 'Show good wind and temp. only'.
(Since AirDat is no longer sharing TAMDAR data with other AMDAR data providers, they no longer have access to the GSD AMDAR display.)

24-Aug-2007 (beta)
Changed header on flight-track window to indicate that quality code 3 can mean 'restricted' as well as 'bad'. Routines changed: Aircraft.

22-Aug-2007 (production and beta)
More changes to restrict TAMDAR fleets according to NOAA-AirDat agreements. Routines changed:, getAcars.cgi, (new)

21-Aug-2007 (production)

17-Aug-2007 (production)

9-Aug-2007 (beta)
Several changes in preparation for the new restrictions in TAMDAR data. Routines changed ACARSLoader, Aircraft, TAMDAROb, getACARS.cgi

7-Aug-2007 (production)

26-April-2007 (beta)

14-Nov-2006 (production)
All beta changes moved to production.

13-Nov-2006 (beta)

9-Nov-2006 (beta and production)

12-Sept-2006 (beta)
Rebuilt the jar file to get the new sounding display software. See for more details.

14-Dec-2005 (beta and production)
Several new airports in central Africa added. Routine changed: airport_info.txt

5-Dec-2005 (beta and production)
Changed the names of the model soundings that can be loaded via the 'Load Other Sdgs' button on the soundings plot to reflect the models that are available on the soundings page. See the sounding page change details for more information.

27-Oct-2005 (beta and production)

5-Oct-2005 (production)

16-Sept-2005 (beta)
We now correctly set the min and max altitude of a flight when all data have bad temperature or wind. (If both W & T of all obs are bad, the min and max altitudes are set to bad values and the flight won't be plotted. Routine changed: Flight.

13-Sept-2005 (oper and beta)
Additional airports added in Africa and the Middle East.

2-Aug-2005 (oper and beta)
Small change to move the placement of the applet to the top of the applet window, for more efficient usage of screen space. Routine changed: MainACARS. Also, added plea to forecasters to take the TAMDAR survey. Routine changed: Welcome.cgi.

1-Aug-2005 (oper)
All beta changes moved to operation, with one exception: E-AMDAR is not yet treated as a separate data source.

12-July-2005 (beta)
Restrict certain users from seeing UAL edr data. Routines changed: Welcome.cgi, ACARSLoader, MainACARS.

11-July-2005 (beta)

29-Jun-2005 (beta)
In the soundings display, changed the calculation of iCAPE (CAPE for an interactive parcel) to only include the area at and above the Level of Free Convection (LFC). (This area is indicated by red hash marks.) Also, the LFC for the parcel (iLFC), if it exists, is shown at the right of the plot. Routine changed: sdg.SkewTPlot.

27-June-2005 (oper and beta)

25-May-2005 (beta)
Broke out E-AMDAR as a selectable data source category. (But this will only work once the underlying processing has been changed, which hasn't occurred yet.) Routines changed: MainACARS, SelectFrame

19-May-2005 (beta)
Added an adjustable mileage marker. To use it, right-click with the mouse and drag to create a labeled mileage marker with nautical miles abd kilometers indicated. Routine changed: map.ZoomCanvas.

11-May-2005 (beta)

5-May-2005 (beta)
Added Profiler locations as an optional overlay, and changed the colors of RAOB sites plotted on the plan-view map. Routines changed: MainACARS, RAOB. Routines added: PROFILER, PROFILERLoader, profiler.txt.

26-April-2005 (oper)

20-Apr-2005 (oper)
All beta changes moved to the operational site.

19-Apr-2005 (beta)

11-Mar-2005 (beta)

8-Mar-2005 (beta)
Changes to accommodate WVSS-II data: For binary formats >= 8, and for vapor data (as distinct from TAMDAR data), we read RHfromWVMR and RHQC along with dewpoint data. In the flight track window for vaporObs, we display the RH and QC flag after the dewpoint. Routines changed: ACARSLoader, VaporOb, Flight, DataPack

7-Mar-2005 (beta)
Changes to ensure that Flights are correctly differentiated. Obs for the same tail number are considered parts of different flights if either

4-Mar-2005 (beta)
Slight change made in the buttons under the sounding display to ensure that long sounding names don't slide off the left edge of the button. (If they're too long, the names will be clipped on the right side, which is the year.)Routine changed lib.MyButton.

23-Feb-2005 (operations)
All beta changes moved to operations.

22-Feb-2005 (beta)
"CIMSS" soundings added. These are soundings taken by the Wayne Feltz of the U. Wisconsin Aerobago team (see These soundings are being taken in Memphis from 22 Feb to 10 March 2005, in support of the TAMDAR Great Lakes Fleet Experiment. Routines changed/added in the sounding display section: reply_setup.cgi, get_cimss.cgi.

18-Feb-2005 (beta)
Location of sounding ID below the SkewTPlot moved slightly to the left so as not to obscure dewpoints so much when multiple plots are overlaid. Routines changed: sdg.SkewTPlot.

7-Feb-2005 (beta)
Icing information in soundings turned off for TAMDAR because we want to keep the sounding displays as similar as possible between 1) the FSL Aircraft Display, 2) the FSL soundings (only) page, and 3) the AWIPS sounding display. Since the latter 2 will not display levels without wind and temperature data (such as levels at which icing is reported), we've turned the icing info off on the soundings display only. (You can still see icing reports on the plan view display, and by right-clicking a flight track.) Routines changed: ACARSSounding.

4-Feb-2005 (beta)
Added icing information to the soundings for TAMDAR observations [But see the change immediately above]. Routines changed: ACARSSounding, Flight, sdg.Sounding, sdg.SoundingLevel, sdg.SoundingLoader, sdg.Stability, sdg.SkewTPlot.

2-Feb-2005 (beta)

1-Feb-2005 (beta)
Added RAOB sites worldwide. Routines added:,; routine changed:

28-Jan-2005 (beta)

21-Jan-2005 (beta)
In the 'select' window, changed 'vg' to 'DEVG' to clarify that it means 'Derived Equivalent Vertical Gust' data, provided by some AMDAR aircraft.

12-Jan-2005 (oper)
  • Canadian data are now flowing
  • All beta changes moved to operations.

    6-Jan-2005 (beta)
    Added option to display only Canadian data. Routine changed:

    4-Jan-2005 (beta)
    Fixed a small bug that caused observations that are part of a sounding to not have a solid line drawn between them if the lowest point of the sounding included bad data. Routine changed:

    15-Dec-2004 (FRD operational and ITS operational)
    • TAMDAR data are now flowing
    • All beta changes moved to operations

    13-Dec-2004 (beta)
    For aircraft data, don't skip levels when plotting the dewpoint (i.e., if the dewpoint exists at both adjacent levels, plot a line between the two dewpoints, otherwise plot no line). This done to keep the dewpoint profile from appearing higher than the temperature profile if the former has missing data. Routine changed: map.SkewTPlot.

    10-Dec-2004 (operational)
    All beta changes moved to operations.

    10-Dec-2004 (beta)
    We now receive and display by the cursor true airspeed for TAMDAR obs. Routines changed: ACARSLoader, TAMDAROb, Flight, DataPack. Format number for the input data is now 7.

    9-Dec-2004 (beta and operational)
    Additional Chinese airports added. No routines changed, but the version of airport_info.txt in the jar file was updated.

    26-Nov-2004 (beta)
    • Changed map.ZoomPanel.stop to avoid a null pointer exception when stop is called before the overlaysFrame is created. Routine changed: map.ZoomPanel.
    • Changed VaporOb to not display dewpoint by the cursor if the dewpoint is MISSING. Routine changed: VaporOb.

    22-Nov-2004 (beta)
    Changes to make use of GPS altitude from TAMDAR. The GPS altitude is shown to the right of the pressure altitude by the cursor for TAMDAR observations. Also, if the airport is known for a sounding, the AGL is shown on the left of the SkewT plot (to the right of the pressure altitude), and the AGL is also shown as the rightmost column of the 'show text' window of the soundings display. Routines changed: ACARSLoader, TAMDAROb, map.SoundingLevel, map.Stability, map.SoundingLoader, map.SkewTPlot, map.Sounding.

    18-Nov-2004 (operatonal)
    All beta changes moved to operational.

    29-Sep-2004 (beta)
    • Changed name from "FSL ACARS Web Display" to "FSL Aircraft Data Display". Routine changed: Welcome.cgi
    • A little change to the show_at_cursor function to accomodate TAMDAR data a little more cleanly. Routines changed: Ob, VgOb, VaporOb, EdrOb, IceOb, TAMDAROb.

    23-Sep-2004 (beta)
    Changes to make the applet reentrant, i.e., multiple copies of the applet running under the same URL will not interfere with one another. New routines: AircraftGroup, map/MapTransform (contains the formerly static parts of GeoPoint). Routines changed: SelectFrame, VORLoader, AirportLoader, Ob, ACARSLoader, Flight, MainACARS, Aircraft, VOR, Airport, map/ZoomPanel, map/ZoomCanvas, map/OverviewFrame, map/GeoPoint.

    21-Sep-2004 (beta)
    • We no longer display dewpoints that are higher than the temperature. Routine changed sdg/SoundingLevel.
    • Changes to support soundings from aircraft data (such as from Japanese airlines) that report altitude based on the local barometer setting. Portions of soundings that have altitudes based on the local barometer setting are indicated by the temperature curve being brown, and by an asterisk after the altitude in the sounding text window. Routines changed: sdg/SoundingLoader, sdg/Sounding, sdg/SkewTPlot, sdg/SoundingLevel, sdg/Stability.

    18-Sep-2004 (beta)
    Changes to support aircraft that report baroAltitude instead of altitude. The variable data_descriptor now has a new meaning: 4 is added to it if the altitude was replaced with baroAltitude. (Routines changed: MainACARS, Flight, ACARSSounding)

    6-20-Aug-2004 (beta)
    Changes to support TAMDAR. (Routines changed: TAMDAROb (new), VgOb, Ob, Aircraft)

    10-May-2004 (beta)
    Changed Labels to MyLabels to avoid the appearence of very large fonts under linux. (Routines changed: MainACARS, lib.MyLabel (new),

    5-Dec-2003 (beta)
    Changed the display_priority method of MainACARS to keep the previously-registered observation if two observations have the same priority. This avoids whole flight tracks disappearing if their obs are 'too' close together. (Routine changed: MainACARS.)

    20-Nov-2003 (beta)
    Changed altitude slider bar to use 500 ft increments. (Routines changed: getACARS.cgi.)

    15-Oct-2003 (operational)
    All beta changes (see below) moved to the operational site.

    9-Oct-2003 (beta)
    Change made to the script that provides data to avoid problems that will occur when we move to a new web server that has bytes in a different order. (Routines changed: getACARS.cgi.)

    29-Sep-2003 (beta)
    Support for data input format 3. The only difference between format 2 and format 3 is that the latter expects lats and lons to be (short)(degrees*182). This was done to avoid problems in the way various machines write floats as binary data. (Routines changed: ACARSLoader.)

    8-Sep-2003 (beta)
    day of month added to the time that appears near the cursor when the cursor is over a data point (e.g., "1314Z/8 indicates the data is from 1314 UTC on the 8th of the month). (Routines changed: Ob.

    19-Aug-2003 (beta)
    Added "all ACARS" and "all MDCRS" categories to select frame. Also added "Canadian" category as a non-enabled place-holder. (Routines changed: SelectFrame, MainACARS)

    14-Aug-2003 (beta)
    Added 'non-AMDAR' category to the select frame. (Routines changed: SelectFrame, MainACARS)

    10-Aug-2003 (beta)
    Slight changes made to the mapping software library to accomodate a different applet. Should cause no changes to this applet's behavior. (Routines changed: map/OverviewFrame, map/ZoomCanvas, map/ZoomPanel.)

    24-July-2003 (beta)
    • Tephigrams are now available on the sounding display. Click the "SkewT/Tephi." button to toggle between SkewT's and Tephigrams. (Routines changed: ACARSSoundingDriver, sdg/SoundingCanvas, sdg/SoundingDriver, sdg/SoundingPanel, sdg/SkewTPlot. Routine added: sdg/ThermoPack.)
    • Can now toggle between two wind scales for the hodograph and the plot on the left: 100 kts and 40 kts. (Routines changed: sdg/SoundingCanvas, sdg/SoundingPanel, sdg/SkewTPlot.)
    • Fixed bug in sdg/ that plotted bad wind speed values on EDR reports.
    • Changes made to decrease the amount of memory used by the sounding package.

    14-Apr-2003 (operational) and 5-Mar-2003 (beta)
    Several changes to make this compatible with Java Runtime Engine 1.4.2, used by Netscape 7 and Mozilla. (Routines changed: MainACARS, Aircraft map/ZoomPanel, map/ZoomCanvas, lib/MyButton, lib/MyUtil, lib/Slider)

    24-Feb-2003 (operational)
    • All beta changes (see below) moved to operations. The Data Source and Icing options won't function until the underlying processing is upgraded, which will occur within a few weeks.
    • Added 3 airports in the Carribian
    • The routine that supports loading only a specific kind of data, or only a specific lat/lon range, which had apparently been broken for many months, has been repaired. Unless you have a slow connection to the internet, you may find it faster to load all the data in a particular time range, and then use the 'Select' window to display only the kind of data you want.

    19-Feb-2003 (beta)
    • Added support for experimental icing data from Delta Airlines. These data support an FAA-funded experiment managed by Marcia Politovich of NCAR. (Routines changed: MainACARS, ACARSLoader, Aircraft, Flight, IceOb (new), LoadFrame)
    • Added support for the Data Source variable, which has the following meanings. (Routines changed: ACARSLoader, Flight, Ob, EdrOb, IceOb, VaOb, VaporOb, VgOb, DataPack)
      • ACARS - data found in only the ACARS data stream (i.e., decoded by FSL)
      • MDCRS - data found in only the MDCRS data stream (i.e., decoded by ARINC)
      • ACARS & MDCRS - data found in BOTH the ACARS and MDCRS data streams.
      • AMDAR - AMDAR data
    • Added to the Select window several additional options:
      • The option to select on data source
      • The option to select aircraft that measure icing. (This is currently an experimental data source.)
      • The option to show only good wind and temperature data. Most notably, selecting this will remove measurements of edr (eddy dissipation rate) and icing that do not include wind and temperature information.
      • (Routines changed: SelectFrame MainACARS)
    • Added an announcement below the map of what data have been selected. This appears in red when anything other than all data have been selected. (Routines changed: MainACARS)

    7-Feb-2003 (beta)
    • Changed the speed slider to not cut off all data above 200 kts. (Routine changed

    6-Jan-2003 (beta)
    • Changed arrangement of overlays to be consistent with the new code in the 'map' package. (Routines changed and many in 'map' package.)
    • Added ARTCC boundaries as an overlay

    16-Jul-2002 (beta and oper)
    Changed processing to better identify US airports. no change to java code

    15-Jul-2002 (beta and oper)
    • Fixed wind barbs on sounding plots to be on the correct side for the southern hemisphere. (Routine changed and
    • Fixed the spacing on the 2-line title at the top of ACARS Skew-T plots to be a little clearer. (For some implementations of java they overlapped a bit. (Routine changed
    • Several new airports added.
    • Upgraded the java libraries: lib, map, sdg to be consistent with other FSL applets. This should cause no new behavior.

    16-Apr-2002 (beta)
    Fixed wind barbs on sounding plots to be on the correct side for the southern hemisphere. (Routine changed and

    15-Apr-2002 (beta and oper)
    Fixed the 21-Mar-2002 correction of wind barbs on the plan-view display. The 21-March code caused problems near the dateline. (Routine changed

    21-Mar-2002 (beta and oper)
    • Corrected an error that caused winds near the edges of the display to be plotted incorrectly, particularly near the equator. Listed values for wind direction have always been correct, however, the barbs were not plotted with right orientation. (Routine changed
    • Corrected an error that caused wind directions on soundings from the RUC and MAPS models to be incorrect. MAPS and RUC winds at longitudes other than 95 West should have been rotated by -sin(25°)*(-95 - longitude), where longitude is in degrees, with E being positive, and the rotation is in degrees. (I.e., a N wind in the RUC domain near the E coast is a NE wind with respect to true N.) This error caused wind directions near the E and W edges of the MAPS/RUC domain to be incorrect by as much as 18°.

    13-Feb-2002 (beta) 21-Mar-2002 (oper)
    • Cleaned up map background around US
    • Information frames can now be expanded and more information will show in them.
    • Added "NOAA / Forecast Systems Lab" credit line

    29-Jan-2002 (oper) and 11-Jan-2002 (beta)
    • Changed screen location of some components to allow easier use on small screens and clearer screen shots in publications.
    • Added a minimum spacing slider to show barbs more clearly (controls minimum spacing in pixels between displayed obs (this also speeds up repainting the screen). This is particularly helpful when displaying wind barbs.
    • You can now set initial defaults (follow the Set initial defaults link) which will allow you to have the page open with the particular display (e.g., Europe or Asia) you wish. (And the Default button will always return you to that display.)
    • Barbs in the Southern Hemisphere now have flags on the correct side of the arrow (pointing to lower pressure).
    • Information at the cursor no longer runs off the screen when the cursor is near the edge of the map.
    • U.S. VORs are now an available overlay.
    • Color coding of vertical gust data is changed to better reflect turbulent conditions.
    • The adiabats on the Skew-T background were changed slightly.
    • The code was upgraded to be more modular, and more consistent with java version 1.1, and other FSL/FRD applets.

    31-Dec-2001 (beta and oper)
    Several additional airports added (airport_info.txt)

    28-Nov-01 (beta)
    Added airport Islamabad.

    19-Nov-01 (beta)
    Lufthansa data added, and additional airports. (airport_info.txt)

    23-Feb-01 (beta)
    Changed minimum gap between "Flights" from 20 min to 25 min to better display text from some AU flights that have obs 21 min apart. (

    4-Jan-01 (beta and oper)
    No longer aborts on bad hourly input files; instead only the bad hour is skipped, and this is reported in the information window under the map. Also, additional airports have been added, and some airport locations corrected.

    All beta processing to date moved to the main java site.

    Cleaned up processing of bad input files slightly. Loading is aborted if a bad file is found, but bad files should no longer generate java errors.

    Added support for Vertical Gust data from some AMDAR reports. The display can be restricted to these data via the select button.

    Changed the MainACARS routine to allow a start time to be specified in the optional applet parameters (in support of the demo java page).

    • Changed the 'load other soundings' functionality to load the MAPS or RUC soundings for the hour before and the hour after a displayed aircraft sounding, by default. (The sounding window doesn't look any different.)
    • Added logging of when the hodograph window is changed between flight track and hodograph.
    • Repaired a subtle error that caused the highlighting of wind and track informatiion on the sounding display to be occasionally in error.

    • For aircraft soundings, the flight track is shown instead of the hodograph, optionally. Use the "Toggle button" in the hodograph window to switch between the two.
    • US projection changed to not include so much of Mexico.
    • zooming function improved.
    • plotting function changed slightly to ensure that all relevant geopolitical segments get plotted (at no reduction in plotting speed).
    • minor error in plotting sounding flight tracks corrected: a line is no longer drawn through points on sounding tracks that have a data descriptor of 3 (these often indicate a bad lat/lon).

    27-Sep-00 (main site), and 24-Aug-00 ('world' site)
    • A long-term error in wind directions has been corrected. Previously, wind directions were not corrected for the angular deviation of compass directions away from the center of the projected map. That is, for example, North winds always pointed straight up, whereas the North direction varied with longitude. This has now been corrected, and wind directions are consistent with geographic directions everywhere.
    • The default US map has been changed back to Lambert Conformal Conic Projection, but with a larger coverage than on the previous conformal US map.
    • The zooming function has been completely rewritten so each zoom generates a new Lambert Conformal Conic Projection with One Standard Parallel. The standard parallel is taken as the center of the zoomed region. Thus, North will always be directly up in the center of any map.
      This new functionality has some implications:
      • When you zoom in on a region, the region that results from the zoom won't exactly match your zoom box, because the old and new maps will have different projections.
      • You can zoom across the dateline and the poles.
      • The overview window generally will show where on the globe your zoomed region is, except when the region extends across a pole.

    2-Aug-00 ('world' site)
    World map implemented (see the 'world' button atop the applet). In addition, the 'Reset Map' button was changed to a 'US' button. Also, the map projection for the US was changed from Lambert Conformal to Cylindrical Equidistant. Note that the world map supports zooms across the dateline.

    19-Apr-00 (operational), 15-Apr-00 (beta)
    • Added color coding by wind speed as an option. Also fixed a bug that occasionally wrote long wind barbs for missing data.
    • Several changes were made to the sounding display to make it consistent with the Soundings from FSL page, as follows:
      • Interactive parcel trajectories: click on the plot to raise a parcel from the clicked point. Click with the right button to call up a dialog that lets you choose td, t, and p for the parcel. Thanks to Tom Whittaker of the University of Wisconsin for providing the core of the code that performs this task.
      • You can now enter an arbitrary 'Site' location as latitude,longitude. For instance: 40.23,-105.78, where the latitude and longitude are in decimal (not degrees.minutes), and West and South are negative.
      • On parcel trajectories, a black horizontal line is shown at the parcel's lifted condensation level (
      • The altitude of the cursor location is now indicated near the cursor, along with pressure and temperature (,
    • You can now 'right-click' with the mouse on a flight track to show all of the available data for that aircraft in a text window. (Previously, you had to 'shift-click'. That option is still available.)

    Updated airport information

    • You can now click on the color bar to restore the complete altitude range.
    • Color-coding for eddy dissipation rate data has been improved: edr values of 0.05 (the minimum) show as light blue, 0.15 shows as purplish, >= 0.25 shows as red.
    • When vertical acceleration or edr data are being displayed, the color bar shows as black, because the color-coding is not by altitude.
    • Fixed a bug that sometimes caused flights to disappear when a portion of the flight was zoomed in on. ( now saves the first and/or last GOOD lat/lon as the start and end points. Previously the first and last location could be missing data.)

    A small change to the load non-ACARS sounding(s) function: RAOB input data now can show minutes. This was made to accomodate CLASS soundings make at Louisville this month in support of a test of UPS humidity measurements.

    Color-coding has been added for vertical acceleration and eddy dissipation rate data. When these data are loaded and/or selected for display, the color coding shows 'normal' data in blue and 'interesting' data in red, and missing data as the bad-data color. The color bar on the right hasn't yet been updated to reflect this.

    • Fixed a bug in the processing of vapor-sensing aircraft that caused the dewpoint to be 0º to 5º (C) too cold, with the largest errors occurring at high mach numbers (which occur at high altitudes). Generally errors in dewpoint below 15,000 ft have been less than 3º C.
    • Added a sort of sounding data by altitude so we don't get those nasty-looking jags when an aircraft doesn't uniformly ascend or descend. Also speeded up the sounding plot generation a little bit, by limiting the maximum number of sounding points to 50, and by writing slightly more efficient code.

    • Corrected a bug generated on 30-Mar that caused missing dewpoint data to be plotted at the temperature value.
    • Also corrected the java data-subset-loader that didn't treat missing data correctly. It now does, and this automatically fixed the problem that caused gaps in the dewpoint line on sounding plots when missing dewpoint data occured.
    • Also fixed vertical acceleration data; it had been referenced to 0-g when full data sets were loaded, but 1-g when a data subset was loaded. It is now referenced to 0-g. That is, light turbulence shows up as deviations from 0, not as deviations from 1.

    Corrected an error that showed dewpoints higher than temperature.

    • Fixed an error that occasionally caused both the ascent and descent portion of a flight track to appear on the same sounding.
    • Rearranged the order of items on the web page above the display so that the most-used links appear directly above the display.

    Can limit the data initially loaded by location and data type by using the Set initial defaults link on the java display. Can also limited the data subsequently loaded by setting parameters in the window that comes up when the Load button is clicked.

    New Web server. Coding between FSL tailnumbers and true tailnumbers remains the same as at the old web server. The new server is a Sun running Solaris 5.6 and Apache 1.3

    • Solid lines connect data points that can probably make useful soundings. Lines are shown if:
      • Barbs are not being shown, and
      • The max altitude of the flight is > 10,000 ft, and
      • The minimum (pressure) altitude of the aircraft is within 2000 ft of the (true) elevation of the airport, and
      • There is no data gap greater than 2500 ft in altitude for data points below 10,000 ft.
    • Data points taken within the last 20 min (with respect to the latest time loaded) are plotted at twice the size of other points (unless barbs are being displayed).
    • From the sounding window, Profiler soundings can be loaded, along with RAOBs and MAPS/RUC soundings.
    • The time of each observation is shown on sounding plots (on the left) and in the sounding text readout.
    • Negative pressure altitudes as well as positive ones are now shown on the sounding plot (on the left).
    • Text printout for soundings and flight tracks are cleaned up a bit.

    • For those aircraft that experimentally measure
      • vertical acceleration
      • eddy dissipation rate, or
      • dewpoint
      this extra data is now loaded, and you can select to display only those aircraft that measure each of these variables by using the select button. This is primarily for the scientists who are working with these data -- the quality of these data is particularly volatile.
    • Textual data for entire aircraft can be generated by shift-clicking anywhere on an aircraft's flight track. The data will appear in a separate window. (You can cut-and-paste the data to transfer it to other programs for processing or printing.) See help for information on the data quality flag F, and other details.
    • More actions (text requests, roaming) are logged on our server (no time penalty on your end).

    • Zoomable soundings with hodographs
    • Actions (zoom, soundings generated, barbs requested, etc.) are logged on our server (no time penalty on your end).

    First java version!

  • Prepared by Bill Moninger,, 303-497-6435
    Last modified: Tue Jan 24 20:48:36 GMT 2017