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HEMS Tool Tutorial

HEMS Tool Tutorial

This section provides information on effectively using the HEMS Tool. The following topics are covered:

Related Information

HEMS Tool Display

HEMS Tool component overview
Figure 1: HEMS Tool component overview

HEMS Tool components:

  • Menu Bar - Drop down menu to access all features and configure display.
    • Weather - Weather images that overlay the base map.
    • Overlays - Weather products (point, polygon) that overlay the weather imagery plus an array of maps and features (nav aids, etc).
    • View - Set of predefined regions to zoom to.
    • Options - Configure various data plots. Opens up a side window.
  • Radar Controls - Controls the looping of the radar imagery. Left arrow slows down the loop. Right arrow speeds it up. Click on pause to pause the loop. In pause mode, the left arrow single steps backwards through the image times. Right arrow single steps forward.
  • Display Time - The time the display is valid for. The data displayed time sync to this time.
  • Time Slider - Thes time slider moves the display time back into the past two hours in 15 minute increments or into the future 6 hours in hour increments.
  • Fullscreen - Allows the display to go full screen and back.
  • Zoom - Allows the user to zoom in and out on the display.
  • Primary Display - The primary area where weather imagery and data overlays will display.
  • Scale - Map scale showing rough distances on plot.
  • Product Labels - Shows what products are on the display including current radar time, wind barb level and weather overlay.
  • Cursor Location - This shows the current location of the cursor. i If Nav Aids are visible, this will show the distance and direction to the nearest navigation aid. Below that is the latitude and longitude of the cursor, default in degrees, minutes and seconds.
  • Legend - Graphical legend for pertinent data shown on the display.

Base Maps

The HEMS Tool has a selection of six base maps: three sets of Esri tiles and three simpler selections. The default is the Esri terrain base map but you can also select a road and satellite view from Esri and light and dark NASA Blue Marble background. These are configurable from the Options menu MAP tab.

Base map configuration
Figure 2. Base map configuration

Weather Data

Weather products in HEMS are divided into two groups. The first are graphical in nature. These are various weather images and are shown under the weather menu. This includes satellite and MRMS radar images, ceiling and visibility data, icing data from CIP and FIP, as well as temperature, relative humidity and wind speed. The satellite, radar and one other weather product can be displayed simultaneously. Visibility can be controlled by adjusting the opacity of each layer through the Options menu.

Satellite imagery is available in either 10km infrared and water vapor or 5km visible. The latest image available for the display time is used.

Infrared satellite imagery example
Figure 3. Infrared satellite image

Radar imagery from the MRMS data is displayed as a loop of 5 images ending in the latest available time. The loop is over 40 minutes.

Radar display example
Figure 4. MRMS Radar display

The other weather images are displayed and a color bar below the display area can be used to determine the meaning of the colors.

Flight category display example
Figure 5. Flight Category weather display

The CIP/FIP and other model data can be displayed at various AGL levels from 1000' to 5000'.

Weather display example
Figure 6. Weather level selection

The display will also label the data being displayed.

Weather display example
Figure 7. Weather level selection

Weather Overlays

In addition to weather imagery, the HEMS Tool offers several weather overlays. This is primarily point data (METARs, TAFs, PIREPs, along with a variety of polygon data (SIGMETs, CWAs and G-AIRMETs). METARs display using the standard station model (see Fig. 4). Clicking on the METAR site will bring up a box with the latest METAR text. If a decoded METAR is desired, that can be set up through the Options menu (see below).

METAR example
Figure 8. METAR display

TAFs can be displayed by using the time slider to move the display time into the future.

The Flight Category plot shows colored dots for each METAR reporting site. Like with the METAR display, these will show the flight conditions from the TAFs when the time slider is moved into the future.
Flight category legend

PIREPs are displayed using the standard symbols for icing and turbulence. Clicking on the symbol will also display a box with more information on the PIREP including the raw text.

PIREP display example
Figure 9. PIREP display

SIGMETs, CWAs and G-AIRMETs are displayed as polygons. The boundaries of the warnings and advisories are in red for SIGMETs, black for CWAs and various other colors for G-AIRMETs. Clicking on the polygon will bring up a box with more information on the advisory including the raw text.

SIGMET display example
Figure 10. SIGMET display

G-AIRMETs display as one layer which can be rather cluttered. Individual types of G-AIRMETs can be toggled on and off via the Options menu. Most G-AIRMETs are polygons such as turbulence and icing. The freezing levels are shown as lines. Areas of multiple freezing levels are shown as a light blue polygon with the level range shown in the label.

G-AIRMET display example
Figure 11. G-AIRMET display

Also, NWS Hazards are included. These are thunderstorm warnings, tornado warnings, winter storm warnings and other watches and advisories. By default all warnings and advisories are shown. The polygons are color coded by type of hazard and a 2 letter descriptor is used as a label. For example: TS=thunderstorm, TO=tornado, WS=winter storm, FF=flash flood.

NWS hazards display example
Figure 12. NWS Hazard display

Finally, model wind barbs can be displayed. These match up with the level selected with the weather imagery, and stay at the selected level when a different weather data product is displayed. The wind barb height that is displayed is labeled at the bottom. These are derived from wind information at each gridpoint. The wind barbs are filtered to eliminate clutter. More barbs will display as the display is zoomed in.

Wind display example
Figure 13. Windbarb display

Map Overlays

In addition to weather overlays, many non-weather overlays are available. The highway layer displays major highways, interstates in the US. The roads layer shows US, state and local roads with more detail being added as the map is zoomed in.

The Nav Aids layer will give you major navigational aids. More will display as the map is zoomed in. A nearest nav aid to the cursor will display in the lower right. In fig. 14, the cursor is located 47 statute miles ENE of the Maples VORTAC.

Navaid display example
Figure 14. Nav Aid display

NavAid Symbols

SymbolType
VORTAC
VOR
VOR/DME
FIX/C
FIX/N
RNAV

The Airports layer will display all airports and heliports from the FADDS 56 day update. Airports will have small airplanes inside the circle and heliports will have an H. Each icon can be clicked for more information.

Airport display example
Figure 15. Airport and heliport display

Airport Symbols

w/Towerwo/TowerType
Airport symbol example Airport, multiple runways, hard surface ≥ 8100 ft, with beacon, with services
Airport symbol example Airport symbol example Airport, single runway, hard surface ≥8100 ft, with beacon, with services
Airport symbol example Airport symbol example Airport, multiple runways, hard surface ≥ 1500 ft < 8100 ft, with beacon, with services
Airport symbol example Airport symbol example Airport, multiple runways, hard surface ≥ 1500 ft < 8100 ft, with beacon
Airport symbol example Airport, multiple runways, hard surface ≥ 1500 ft < 8100 ft, with services
Airport symbol example Airport symbol example Airport, multiple runways, hard surface ≥ 1500 ft < 8100 ft
Airport symbol example Airport symbol example Airport, single runway, hard surface ≥ 1500 ft < 8100 ft, with beacon, with services
Airport symbol example Airport symbol example Airport, single runway, hard surface ≥ 1500 ft < 8100 ft, with beacon
Airport symbol example Airport symbol example Airport, single runway, hard surface ≥ 1500 ft < 8100 ft, with services
Airport symbol example Airport symbol example Airport, single runway, hard surface ≥ 1500 ft < 8100 ft
Airport symbol example Airport symbol example Airport, short or unpaved runway, with beacon, with services
Airport symbol example Airport symbol example Airport, short or unpaved runway, with beacon
Airport symbol example Airport symbol example Airport, short or unpaved runway
TypeType
Airport symbol examplePrivate Airport
Airport symbol exampleGeneric Airport
Airport symbol exampleHeliport
Airport symbol exampleSeaplane Base

NOTE: Runway configurations not represented in airport icons.

Panning and Zooming the Map

The map can be panned using the mouse. By clicking the left mouse button in the display area and moving it, the map will pan. One the mouse button is release, the data will refresh to the new display area. On a tablet, touching the display area and dragging will pan the map.

There are several ways to zoom in and out. The +/- buttons in the upper left corner of the display area can be used. Also, if the mouse has a scroll wheel, it can be used to zoom in and out depending on the direction the wheel is moved. On a tablet, pinch zooming is available. Finally, by holding the shift key while pressing the left mouse button, a zoom region can be selected. A red box will display and once the mouse button is release, the closest region to the zoom box will be displayed. Since OpenLayers uses an integral zoom level with each level being twice the magnification, exact zooms are not possible.

Time Controller

The time display and slider are available in the upper right portion of the display. The display time will always show the current valid time for data in the display. The time slider is centered on the current hour, which is highlighted in orange (see Fig. 16). Moving the slider to the right will move forward in time up to 6 hours. Moving the slider to the left will move backward in time up to 2 hours in 15 minute increments. A "Now" button is available to quickly return to current conditions.

Time slider
Figure 16. Time display and time slider

All data are synchronized to the time slider. For example, moving back in time will reset valid times for METARs, SIGMETs, G-AIRMETs, etc. Weather images will also display analyses valid for the new valid time including satellite imagery, CIP/FIP and past model data. The radar loop will reset to show the latest 40 minutes of radar data in a loop terminating in the valid time.

If the time is moved forward, the display will now show forecasted data. Analyses of ceiling, visibility and flight category will be replaced with forecasts of the same information. At this time, there is no forecast satellite or radar data so those layers will turn off. But METARs will be replaced with TAFs and CIP will be replaced with FIP.

Radar Control

In the upper left is the radar controlsi (see Fig 17). This allows the user to pause and loop the radar images. By default, the radar loops the last 30 minutes of radar data in 10 minute increments. In loop mode, the left arrow slows the loop down. The right speeds the loop up. In pause mode, the left arrow single steps backwards through each time. The right arrow single steps forward in time.
Radar controls
Figure 17. Radar controls

Full Screen Mode

The display can be rendered to full screen mode using the full screen button in the upper right part of the display (see button to right of "Now" in Fig. 16). The menu bar will remain at the top of the screen but the rest of the display will now cover the full screen. Hitting escape or pressing the full screen button again will return the display to normal view.

NOTE: In full screen mode, a button will appear to show the legends. Click the button again to hide the legends.

Configuring Specific Weather Overlays

METARs

The Options menu DATA tab METAR/TAF subtab offers the ability to change the METAR display.

METAR and TAF configuration
Figure 18. METAR/TAF configuration
  • Each parameter in the station model plot can be turned on and off. A quick "All" or "None" button is available to toggle on or off all parameters. If a single parameter is desired, it will be plotted at the station location. If more than one, those will plot in their normal locations in the station model.
  • The "Density" setting relates to how many METARs will be displayed at any time. A priority scheme is used for progressive display of METARs. The higher the zoom level, the more stations will plot. But the density for a particular zoom level can be changed through the density setting. Going to +1 will roughly double the number of stations in the plot. Going to -1 will cut the number in half.
  • The Scale setting will scale the data icon on the screen. In some cases, a larger icon is desired. A setting of 1.5 will scale the station model up by 50%.
  • The Decoded METAR toggle will cause the data displayed in the popup box to show a decoded METAR rather than the raw METAR text.
  • The Include TAF toggle will add the latest valid TAF to the popup display.

Flight Category

The Options menu DATA tab FLTCAT subtab offers the ability to change the Flight Category display.

Flight category configuration
Figure 18. Flight Category configuration
  • The "Density" setting relates to how many flight category sites will be displayed at any time.
  • The VFR setting will toggle on and off those sites that are under VFR conditions to eliminate clutter.

PIREPS

The Options menu DATA tab PIREP subtab offers the ability to change the PIREP display.

PIREP configuration
Figure 19. PIREP configuration
  • The turbulence, icing, weather, and misc. PIREPs can be selectively displayed.
  • An altitude range for PIREPs can be set. This way the PIREPs outside of the flight altitudes can be filtered out. For the HEMS Tool the top altitude is preset to 12,500' to eliminate high altitude PIREPs that are of no concern to low level operations.
  • The age of the PIREPs can be set. By default, the latest 90 minutes of PIREPs up to the valid time are displayed.
  • The minimum intensity of the PIREPs can also be set. This way the user, if needed, can select only moderate to severe PIREPs for display.
  • The scale factor of the icons can be set for easier viewing.

SIGMETs

The Options menu DATA tab SIGMET subtab offers the ability to change the SIGMET display.

SIGMET configuration
Figure 20. SIGMET configuration
  • The various types of SIGMETs can be toggled on and off. The convective includes US convective SIGMETs and international thunderstorm related SIGMETs. Turbulence includes MTW (Mountain Wave) and LLWS (Low level wind shear) SIGMETs. IFR includes dust and sand storm as well as mountain obscuration SIGMETs. Icing PIREPs can be selectively displayed.
  • The show heights option will add the range of heights for the SIGMET to the label. This can add extra clutter so it is off by default.

G-AIRMETs

The Options menu DATA tab GAIRMET subtab offers the ability to change the G-AIRMET display.

G-AIRMET configuration
Figure 20. G-AIRMET configuration
  • The various types of G-AIRMETs can be toggled on and off. All the G-AIRMET types are on by default to show an overview but it is likely only specific G-AIRMETs such as LLWS or icing will be desired.

Hazards

The hazards configuration allows the user to switch from all hazards to just warnings.

Hazards configuration
Figure 21. Hazard configuration

Wind Barbs

This allows the user to change the density of wind barbs. "+1" doubles the number of barbs. "+2" quadrupals the number. "-1" cuts the number in half.

Wind configuration
Figure 22. Wind barbs configuration

Hover

By default, features on the display have to be clicked on to show the popup information boxes. This is done to support mobile devices that don't support a hover feature. By toggling hover on, the features will automatically show the popup when the mouse is moved over them.

Browser Storage

The current state of the HEMS Tool is saved in browser storage so that a return to the HEMS Tool will recover some of the user settings. These include:

  • hemstmapinfo - This saves the current center latitude, longitude, and zoom level for the display.
  • hemstmapbase - This saves the type of basemap being used (terrain, satellite, light, etc).
  • hemstmapover - This saves a list of the map overlays being used (highways, navaids, etc).
  • hemstdata - This saves a list of weather data layers being displayed (rad, metar, sigmet, etc).
  • hemstwx - This saves the weather layer being displayed (fltcat, cip010, spd030, etc).

URL Options

Here is a list of the URL options:

  • date=yyyymmddhhnn - This selects a specific date and time to display.
  • time=hr - This selects the initial time on the time slider (def: 0).
  • timelabform={full|simple} - This selects time slider labels. Full shows -/+ hours from current. Simple shows just the time and "Forecast for" if it's a future time.
  • refresh=min - This sets the auto-refresh time interval (def: 2 min).
  • tz=tz - This sets the time zone to show in the date header. This can be "local" which is the browser time zone or "label,offset" which is the zone name and offset in hours. For example "CDT,-5". (def: UTC).
  • region=reg - This will center the map to a specific region. Options include: "conus", "us", "northeast", "ne", "southeast", "se", "northcentral", "nc", "southcentral", "sc", "northwest", "nw", "southwest", "sw", "alaska", "ak", "hawaii", "hi", "gulfmexico", "gmx", "caribbean", "car", "europe", "eur", "southamerica", "sam", "easia", "eas", "australia", "aus", "zab", "zau", "zbw", "zdc", "zdv", "zhu", "zfw", "zid", "zjx", "zkc", "zla", "zlc", "zma", "zme", "zmp", "zny", "zoa", "zob", "zse", "ztl" (def: none).
  • center=lat,lon - This will center the map at a specific latitude and longitude. The default is 39,-97.
  • zoom=level - This sets the zoom level. The default is 4. A higher number zooms in. A lower number zooms out.
  • fullmode=(screen|window) - This sets the full screen mode. "screen" sets it to full screen. "window" sets it to fill the current browser window. The default is screen.
  • fullscreen=(on|off) - This sets the display to go into full window if fullmode=window.
  • basemap=(esri_terrain|esri_road|esri_sat|light|dark|simple) - This selects the type of basemap. The default is esri_terrain.
  • sat={on|off} - This turns the satellite layer on or off. The default is off.
  • satprod={ir|vis|wv} - Specifies the type of satellite image. The default is ir.
  • satopacity=# - Specifies the satellite image opacity (0=transparent to 1=opaque). The default is .5.
  • satloop={on|off} - Specifies whether the satellite is looping on page load. Default is on.
  • satimages=# - Specifies the number of images in satellite loop. The default is 5.
  • satlabform={on|simple|off} - Specifies the satellite label format. The choices are "on" which shows type of image and time, "simple" which shows only image type and "off" which shows no label. The default is "full".
  • rad={on|off} - This turns the radar layer on or off. The default is on.
  • radprod={rala|cref} - Specifies the type of radar image: "rala" for reflectivity at lowest altitude or "cref" for composite reflectivity. The default is rala.
  • radopacity=# - Specifies the radar image opacity (0=transparent to 1=opaque). The default is .75.
  • radloop={on|off} - Specifies whether the radar is looping on page load. Default is on.
  • radimages=# - Specifies the number of images in radar loop. The default is 5.
  • radlabform={on|full|simple|off} - Specifies the radar label format. The choices are "on" or "full" which shows type of radar and time, "simple" which shows only radar type and "off" which shows no label. The default is "full".
  • weather={on|off} - This turns the weather layer on or off. The default is off.
  • wxtype=type - This sets the weather type. The default is fltcat.
    • none - no weather image displayed
    • lamp15_sfc_fltcat - flight category
    • lamp15_sfc_ceil - ceiling
    • lamp15_sfc_vis - visibility
    • fip_010a_sev, fip_020a_sev, etc - icing severity at 1000' AGL, 2000' AGL, etc
    • fip_010a_prob, fip_020a_prob, etc - icing probability at 1000' AGL, 2000' AGL, etc
    • rap_010a_temp, rap_020a_temp, etc - temperature at 1000' AGL, 2000' AGL, etc
    • rap_010a_rh, rap_020a_rh, etc - relative humidity at 1000' AGL, 2000' AGL, etc
    • rap_010a_wspd, rap_020a_wspd, etc - wind speed at 1000' AGL, 2000' AGL, etc
  • wxopacity=# - Specifies the weather image opacity (0=transparent to 1=opaque). The default is .75.
  • wxlabform={full|simple} - Specifies the weather label format. The choices are "simple" which just lists the parameter or "full" which lists the model and product time. The default is full.
  • metar={on|off} - This turns the METAR layer on or off. The default is off.
  • metplot=param - This selects the display parameter. The default is model. Multiple parameters can be selected separated by commas. Options are:
    • model - station model, all on
    • temp - temperature
    • dew - dewpoint
    • rhum - relative humidity
    • alt - altimeter setting
    • vis - visibility
    • ceil - cloud ceiling
    • cover - cloud cover
    • wind - wind barb
    • wspd - wind speed
    • wgst - wind gust
    • cat - flight category
    • wx - weather symbol
    • id - station identifier
  • metdensity={-1|0|+1|+2} - The METAR data density. The greater the number the more stations will plot. The default is 0.
  • metdecoded={on|off} - Specifies to show decoded data in popup dialog box. The default is off.
  • metrawtaf={on|off} - Specifies to add TAF to popup dialog box. The default is on.
  • metscale=## - Specifies scale factor for the data icon. The default is 1.
  • fltcat={on|off} - This turns the flight category layer on or off. The default is on.
  • fcdensity={-1|0|+1|+2|+3} - The FltCat data density. The greater the number the more stations will plot. The default is +2.
  • fcvfr={on|off} - Specifies whether to display VFR stations or not. The default is off.
  • fctaf={on|off} - Specifies whether to display raw TAF in popup. The default is off.
  • fcscale=## - Specifies scale factor for the icon. The default is off.
  • airep={on|off} - This turns the AIREP/PIREP layer on or off. The default is on.
  • airtype=param - This selects the type of AIREP data to display. The default is all. Multiple types can be selected separated by commas. Options are:
    • turb - Turbulence reports
    • icing - Icing reports
    • wx - Reports with weather (temp, clouds)
    • misc - Other reports
  • airtop=## - Specifies top level in hundreds of feet of AIREPs to display. The default is undef.
  • airbottom=## - Specifies bottom level in hundreds of feet of AIREPs to display. The default is undef.
  • airage=## - Specifies age in hours of AIREPs to display. The default is 1.5 (90min).
  • airinten=## - Specifies minimum intensity of AIREPs to display. Options are "all", "lgt" for light, "mod" for moderate and "sev" for severe. The default is all.
  • airscale=## - Specifies scale factor for the AIREP icon. The default is 1.
  • airnoneg={on|off} - Specifies not to plot PIREPs with negative turb and ice reports. The default is off.
  • sigmet={on|off} - This turns the SIGMET layer on or off. The default is on.
  • sigtype=param - Specifies the types of SIGMETs to display. The default is all. The types are:
    • trop - tropical cyclone
    • conv - convective
    • turb - turbulence
    • ice - icing
    • ifr - IFR
    • va - volcanic ash
  • sigopacity=# - Specifies the SIGMET polygon opacity (0=transparent to 1=opaque). The default is .75.
  • sigheight={on|off} - This turns the SIGMET height labels on or off. The default is off.
  • gairmet={on|off} - This turns the G-AIRMET layer on or off. The default is off.
  • gairtype=param - Specifies the types of G-AIRMETs to display. The default is all. The types are:
    • turb-hi - high level turbulence
    • turb-lo - low level turbulence
    • llws - low level wind shear
    • sfc-wind - high surface winds
    • icing - icing
    • fzlvl - freezing levels
    • ifr - IFR
    • mtn - mountain obscurations
  • gairopacity=# - Specifies the G-AIGMET polygon opacity (0=transparent to 1=opaque). The default is .25.
  • cwa={on|off} - This turns the CWA layer on or off. The default is off.
  • cwatype=param - Specifies the types of CWAs to display. The default is all. The types are:
    • conv - convective
    • turb - turbulence
    • ice - icing
    • ifr - IFR
    • pcpn - precipitation
  • cwaopacity=# - Specifies the CWA polygon opacity (0=transparent to 1=opaque). The default is .75.
  • hazard={on|off} - This turns the NWS hazards layer on or off. The default is off.
  • haztype={all|warn} - Specifies level of hazards. The default is all.
  • hazopacity=# - Specifies the hazard polygon opacity (0=transparent to 1=opaque). The default is .5.
  • windbarb={on|off} - This turns the windbarb layer on or off. The default is off.
  • wbdensity={-1|0|+1|+2} - The windbarb density. The greater the number the more barbs will plot. The default is 0.
  • wbscale=## - Specifies scale factor for the windbarb icon. The default is 1.
  • wblabform={full|simple} - Specifies the windbarb label format. The choices are "simple" which just lists the parameter or "full" which lists the model and product time. The default is full.
  • highways={on|off} - Turns highway layer on or off. These are primarily interstates. The default is off.
  • roads={on|off} - Turns roads layer on or off. These are primarily US and state highways plus some city streets. The default is off.
  • counties={on|off} - Turns county layer on or off. The default is off.
  • jetroutes={on|off} - Turns the jetroutes layer on or off. The default is off.
  • firs={on|off} - Turns the ARTCC/FIR layer on or off. The default is off.
  • navaids={on|off} - Turns the Nav Aids layer on or off. The default is off.
  • navscale=## - Specifies scale factor for the Nav Aid icon. The default is 1.
  • navlabel={on|off} - Turns the Nav Aid labels on or off. The default is off.
  • airports={on|off} - Turns the airports layer on or off. The default is off.
  • arpttype=param - Specifies the types of Airports to display. The default is all. The types are:
    • pub - public airports
    • priv - private airports
    • mil - military airports
    • hel - heliports
    • sea - seaplane bases
  • arptscale=## - Specifies scale factor for the airport icon. The default is 1.
  • arptlabel={on|off} - Turns the airport labels on or off. The default is off.
  • runways={on|off} - Turns the runways layer on or off. The default is off.
  • metric={on|off} - Specifies to display data in metric units. The default is off.
  • mouseformat={deg|dm|dms} - Specifies to format for the mouse location: degrees, degree/frac. minute, degree/minute/second. The default is deg.
  • level=## - Specifies value of the level in the level slider. The default is none.
  • hover={on|off} - Turns on hover for features. The popups will come up when mouse hovers. Default is off.