Figure 6-9. HEMS Relative Humidity-Example Helicopter Emergency Medical Services Tool INFO Feedback weather Overlays View Configure 1605 UTC 7 May 2015 .. Satellite Radar O None
• Flight Category
• Ceiling
• Visibility Icing Severity >> Icing Probability >> Temperature >> Rel Humidity >> @1000 AGL Wind speed >> • @2000' AGL
• @3000 AGL
• @4000' AGL
• @5000' AGL Source: Esri 500 km 500 mi RAP Rel humidity at 5000 AGI RAP Wingbarb at 5000 AGL
SIGMET CWA FIt Cat: •MVFR • IFR O LIFR PIREP Turb: ALGT A MOD A SEV PIREP Ice: LJ LGT / MOD H SEV 10 20 30 40 50 60 70 80 90 The humidity data are colored from oranges for very dry, to yellow for 50 percent, to dark green for near 100 percent. Oranges would be more indicative of clear skies while greens would show cloud or low-visibility areas.
Figure 6-10. HEMS Wind Speed with Windbarb-Example Helicopter Emergency Medical Services Tool INFO Feedback weduen Overlays View Configure 1607 UTC 7 May 2015
• Satellite
- Radar O None
- Flight Category
• Ceiling © Visibility..
Icing Severity >> Icing Probability >> Temperature >> Rel Humidity >> › @1000' AGL
• @2000' AGL
• @3000' AGL
• @4000' AGL _ Sourde: Esri 500 500 mi RAP Wind speed at 5000 AGL RAP Wing barb at 1000 AGL FIt Cat: •MVFR • IFRO LIFR PIREP Turb: ALGT AMOD A SEV PIREP Ice: LJ LGT / MOD (/ SEV 45 60 75 The wind speed data are colored from blues for the lightest winds to light green for stronger winds.
6-9
6-10
6.1.2.6 Dat a Overlays.
The HEMS Tool allows the user to select multiple fields to be overlaid on the grids including: METARs/TAFs, Flight Category, PIREPs, Windbarbs, SIGMETs and G-AIRMETs (Graphical Airmen’s Meteorological Information), CWAs, and NWS hazards. These fields may be selected on or off in the drop-down Overlays menu. Figure 6-11, HEMS Data Overlays with Text METAR—Ex ample, is an example.
6.1.2.6.1 METARs/TAFs.
The METAR observations plotted using the standard station model where temperature, dewpoint, winds, altimeter setting, weather, ceiling, and visibility are displayed around the station location.
T he data plotted comes from the latest available observation, including Special Weather Reports (SPECI). The stations displayed follow a progressive priority scheme that will show more stations depending on how far the user zooms in. This density can be changed through the Configuration menu. If the time slider is moved into the past, the nearest observation before the listed time is displayed. If the slider is moved into the future, the TAF for that station is shown. It should be noted there are fewer TAF stations than available METAR sites. More configuration options are available, including parameters displayed, scale factor of graphic, and whether the TAF is included in the pop-up display.
6.1.2.6.2 Flight Category.
This displays only the flight conditions at a particular airport as a colored dot.
The flight category display uses the same priority filter system as the METAR plots, but the density is much higher.
6.1.2.6.3 PIREPs.
This displays turbulence and icing PIREPs. The default is to show only PIREPs reported in the last 90 minutes, and only those below 12,500 ft. These options can be changed in the Configuration menu.
6-11
6.1.2.6.4 SIGMETs.
This displays the current valid SIGMETs. This will show both domestic and international SIGMETs. Individual SIGMET types can be toggled on and off through the configuration menu. SIGMETs can be distinguished by their red outline and red labels.
6.1.2.6.5 G-AIRMET.
This displays the current valid G-AIRMETs. This will show all G-AIRMET types, which can be cluttered. Each type can be toggled on and off through the Configuration menu.
6.1.2.6.6 Center Weather Advisories (CWA).
This displays the CWA issued by the Center Weather Service Units (CWSU) at each Air Route Traffic Control Center (ARTCC). CWAs can be distinguished by the black outline and black labels.
6.1.2.6.7 NWS Hazards.
This displays all current warnings, watches, and advisories. The Configuration menu will allow the user to select “Warnings” which will only show tornado, severe thunderstorm, blizzard, winter storm, and ice storm warnings.
6.1.2.6.8 Windbarbs.
This displays windbarbs from the RAP model based on the height selected through one of the weather displays (CVA, Icing and RAP temperature, relative humidity (RH), and wind speed). If the user selects temperature at 2,000 ft AGL, the display would also show the winds at 2,000 ft AGL. The windbarbs are filtered based on zoom level. As the display is zoomed in, more windbarbs will show.
Figure 6-11. HEMS Data Overlays with Text METAR-Example Helicopter Emergency Medical Services Tool INFO Weather Overlays View Configure 1625 UTC 7 May 2015 -A SPER • METAR/TAF
• FItCat 45
• PIREP
• SIGMET
• G-AIRMET
• CWA
- NWS Hazards
• Windbarb
• Highways
• Roads
- Counties IN ACE PR RNO
• Top Jetroutes
• ARTCC Boundaries
- Nav Aids
• Airports Runways
OLORADO
PL A TA OU 'MEX 100 mil 28 || KTCS
SIGMET CWA GAIRMET E FIt Cat: OMVFRO IFRO LIFR PIREP Turb: ALGT AMOD A SEV PIREP Ice: L LGT If MOD | SEV Note: Text information from these fields can be accessed by clicking on the station or in the polygon, or by selecting "hover" in the Configure menu and scrolling the mouse over the area of interest.
Data can be customized in the Configure menu (see Figure 6-12, Configure Menu-Example). The user can select the type of background map; the level of transparency for the weather overlays; the types of SIGMETS, G-AIRMETs, PIREPS, and NWS hazards they wish to view; the preferred satellite view; and the density of observations.
6-12
Figure 6-12. Configure Menu-Example Helicopter Emergency Medical Services Tool INFO Feedback Weather Overlays View Contigure 1619 UTC 7 May 2015 Map >> Satellite >> Radar >> Weather >> METAR/TAF >> Parameters visible:
Flight Cat >> All • Temp Wind Alt PIREP >> • Vis OWx • Cover • Ceil SIGMETS >> None Dew OWgst • Id G-AIRMET >> Density: 0 Scale: 1 Hazards >>
• Hover • Include TAF • Decoded METAR ÍCO 100 km / 995 A RAW E 69 100 mil KROW
SIGMET CWA GAIRMET FIt Cat: •MVFR • IFRO LIFR PIREP Turb: ^ LGT AMOD SEV PIREP Ice: LJ LGT / MOD (/ SEV
6.1.2.7 ESRI Basemaps and Overlays.
The HEMS Tool has high-resolution basemaps for the entire United States.
More detail is revealed as the user zooms in. The user can select their preferred Environmental Systems Research Institute (ESRI) basemap through the HEMS Configure menu. Options include Terrain, Road, or Satellite, and the user can select a light, dark, or simple map background. The default basemap is the ESRI Terrain view.
Map overlays include highways, roads, counties, top jet routes, ARTCC boundaries, Navigation Aids (NAVAID), airports, and runways. These can be toggled on or off in the Overlays menu.
6.1.3 Strengths and Limitations.
6.1.3.1 HEMS Strengths.
1. One-stop shop for multiple data fields.
2. Focused on low-altitude flights common to HAA.
3. Simplified display for non-meteorologist users.
4. Available 24 hours a day, 7 days a week.
6.1.3.2 HEMS Limitations.
1. Due to limitations of the observations, the ceiling, visibility, and flight category grid cells are approximately 5 km apart. In data 6-13
6-14 sparse regions, the best possible estimate of ceiling and visibility is assumed from the nearest surrounding data and may not represent the actual conditions at a specific point.
2. Due to limitations of the radar, such as blockage by mountains, spacing of radar locations and over processing of clutter and AP, there may be precipitation when radar data does not detect or show a complete weather picture. The most commonly seen example is very shallow clouds with light precipitation, like freezing drizzle or snow. An excellent website with more information concerning radar technology and limitations is found at the NWS JetStream-Online School for Weather, under Radar Frequently Asked Questions (FAQ).
3. In regions of steep terrain, AGL altitudes may have significant deviations from actual height above terrain, given the limiting factor of grid cell size, which is approximately 13 km, and the resolution of the topography in the model.
6.1.4 Use.
The HEMS Tool has been specially designed to meet the needs of emergency first responders flying short-distance, low-altitude flight routes. This tool is not designed for General Aviation (GA) or commercial flights and does not constitute an official weather brief.
6.2 Flight Path Tool.
6.2.1 Description.
The FPT is a comprehensive, interactive, geographical display that brings together all of the weather products available at https://www.aviationweather.gov/flightpath. It runs as a Java desktop application on your computer for maximum performance.
The Flight Path Tool can overlay multiple fields of interest: icing (probability, severity, and Supercooled Large Drops (SLD)), turbulence potential, Convective diagnosis and forecast, ceiling, visibility, flight category, winds, relative humidity, temperature, radar (base and Composite Reflectivity), satellite observations (visible, infrared (IR), and water vapor wavelengths), AIRMETs and SIGMETs, METARs, TAFs, and PIREPs.
All 3-D data can be sliced horizontally at selected flight levels or vertically along a flight path. All data can be animated in time.
The tool lets you zoom in to any location on the globe. It automatically switches to the most appropriate projection for the viewed area. High-resolution base maps show selectively more detail as you zoom in.
In addition, the FPT can create vertical cross sections along your flight route.
Preferred views can be saved for quick recall later.
Discussion Credit: NOAA/NWS/AWC.
Figure 6-13. Flight Path Tool-Icing Severity Example (Image Credit: AWC) View Configure
14.000
42.000 40,000 38,000
10.000
8.,000
6.000
4.000 2,000 Light Icing Severity 13:30Z 16:30Z 18:00Z 19:30Z 21:00Z 22:30Z 0:00Z 5/3 5/4 Data Layers Available Data Sets
• Icing SLD
• Icing Severity
- Data Overlays _ Wind Barbs 6-15
Figure 6-14. Flight Path Tool-Windbarbs Example (Image Credit: AWC)
• Flight Path Tool (Default Configuration) File View Configure
44.000
40.000
26.000
22.000
20.000
18.000
8.000 4,000 2,000 eet Valid at 05/03/17 182 cing Severit 2 hrtosttor 10000 Feet Valid at 05/0347 18z None Icing Severity 15:30Z 16:302 19:30Z 21:00Z 22:30Z 0:00Z 1:30Z 3:00Z 5/3 514 Data Layers Available Data Sets
• Wind Barbs •
• METARs — PIREPs
• AIR/SIGMETs 6-16
Figure 6-15. Flight Path Tool-Cross Section Example (Image Credit: AWC)
• Cross Section File View Configure
44.000
42.000
41.000
40.000
39.000
38.000
37.000
36.000
35.000
34.000
33.000
32.000
31.000
28.000
27.000
25.000
24.000
22.000
22.000
21.000
20.000
19.000
18.000
12.000
16.000 ·
15.000
14.000 Г -T 1000 6-17
Appendix A A-1 APPENDIX A. DEFINITION OF COMMON TERMS USED IN EN ROUTE
FORECASTS AND ADVISORIES Table A-1. Definition of Common Terms Used in En Route Forecasts and Advisories (FA, SIGMET, AIRMET, TCA, VAA, ROFOR) Contraction Translation Definition EMBD Embedded Thunderstorms or Cumulonimbus Thunderstorms or cumulonimbus (CB) clouds that are embedded in cloud layers or concealed by haze.
EXTREME TURB Extreme Turbulence Turbulence in which aircraft is violently tossed about and is practically impossible to control. It may cause structural damage.
FIR Flight Information Region An airspace of defined dimensions within which flight information service and alerting service are provided.
FL Flight Level A surface of constant atmospheric pressure which is related to a specific pressure datum, 1013.2 hectopascals (hPA), and is separated from other such surfaces by specific pressure intervals.
FRQ Frequent Thunderstorms or Cumulonimbus Consisting of elements with little or no separation between adjacent thunderstorms with a maximum spatial coverage greater than 75 percent of the area affected by the phenomena at a fixed time or during the period of validity.
IMC Instrument Meteorological Conditions Ceiling greater than or equal to 500 feet to less than 1,000 feet and/or visibility greater than or equal to 1 to less than 3 miles. LIMC is a sub-category of IMC, thus, IMC conditions are ceiling less than 1,000 feet and/or visibility less than 3 miles.
ISOL Isolated Thunderstorms or Cumulonimbus Consisting of individual features affecting an area with a maximum spatial coverage less than 50 percent of the area affected by the phenomena at a fixed time or during the period of validity.
LINE TS Line (of Thunderstorms) A line of thunderstorms being at least 60 miles long with thunderstorms affecting at least 40 percent of its length.
LIMC Low Instrument Meteorological Conditions Ceiling less than 500 feet and/or visibility less than 1 SM. LIMC is a sub-category of Instrument Meteorological Conditions.
Appendix A A-2 Contraction Translation Definition MVMC Marginal Visual Meteorological Conditions Ceiling greater than or equal to 1,000 feet to less than or equal to 3,000 feet and/or visibility greater than or equal to 3 to less than or equal to 5 miles.
MOD ICE Moderate Icing The rate of accumulation is such that even short encounters become potentially hazardous and use of deicing/anti-icing equipment or diversion is necessary.
MOD TURB Moderate Turbulence Turbulence that causes changes in attitude (pitch, roll, yaw) and/or altitude, but the aircraft remains in positive control at all times. It usually causes variations in indicated airspeed.
MT OBSC Mountain Obscuration Conditions over significant portions of mountainous geographical areas are such that pilots in-flight should not expect to maintain visual meteorological conditions or visual contact with mountains or mountain ridges near their route of flight.
OBSC Obscured Thunderstorm or Cumulonimbus Obscured by haze, smoke, or cloud or cannot be readily seen due to darkness.
OCNL Occasional Thunderstorms or Cumulonimbus An area with a maximum spatial coverage between 50 and 75 percent of the area affected by the phenomena at a fixed time of during the period of validity.
SCT Scattered 25 to 50 percent of area affected.
SEV ICE Severe Icing The rate of accumulation is such that normal deicing/anti-icing equipment fails to reduce or control the hazard. Immediate diversion is necessary.
SEV TURB Severe Turbulence Turbulence that causes large, abrupt changes in altitude and/or attitude. It usually causes large variations in indicated airspeed. Aircraft may be momentarily out of control.
VMC Visual Meteorological Conditions Ceiling greater than 3,000 feet and visibility greater than 5 miles.
Appendix A A-3 Contraction Translation Definition
VOLCANIC
ERUPTION Volcanic Eruption A volcano eruption has occurred when an eruption report is received from a volcano observatory. A volcanic eruption is also considered to have occurred regardless of volcano observatory notification if reported by PIREP, or ground observer, or if remote sensing data indicates that an eruption has occurred based on satellite imagery or WSR-88D radar data or any other reliable sources are identified.
VOLCANIC ASH Volcanic Ash Any ash that can be seen by any one or more of the following: satellite imagery (visible, IR, multi-channel or TOMS), PIREPs, ground observations, radar and VAFTAD (In the event volcanic ash is entrained in clouds, the volcanic ash will be treated as visible using the VAFTAD as guidance).
WDLY SCT Widely Scattered Less than 25 percent of area affected.
WDSPR Widespread 50 percent or greater of the area affected.