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AvnWx Icons

Icons are used to present summarized information quickly. Different symbols are used for different types of data and, for most, different colors and symbols are displayed on the icon to show additional information.

Rolling the mouse over an icon will display detailed information, usually including the raw (i.e., encoded) report and a summary of major elements in the report. Note: Be sure to look at the raw details as often there are important details included with the remarks.

Clicking on an icon will also display detailed information, and will disable mouse roll-over. This may be useful if you need to copy information from the details, or if you want to click on a link within the detailed report. To update detailed display, either click on a different icon, or click on the detailed display itself, which will re-enable mouse roll-over.

Rolling over the map will show information about TFRs, AIRMETs and SIGMETs (if any) at the current mouse location, and clicking on the map will display AIRMET and SIGMET details and disable mouse roll-over.

METARs

METARs are displayed as blue-tinted circles, with the standard Aviation Flight Category colors and Cloud Coverage symbols. The Cloud Coverage displayed is based on the greatest coverage, regardless of altitude.

Magenta LIFR (Low IFR) - Ceiling below 500' and/or Visibility less than 1 mile or indefinite ceiling due to poor vertical visibility (METAR code VV)
Red IFR - Ceiling 500 to 1000' and/or Visibility 1 to less than 3 miles
Blue MVFR (Marginal VFR) - Ceiling 1,000 to 3,000 and/or Visibility 3 to 5 miles
Green VFR - Ceiling greater than 3,000 and Visibility greater than 5 miles
SKC: Open Circle icon indicates clear sky (no cloud cover). Note that Visibility may still be restricted such that you may not have a green VFR icon.
CLR: Open Square icon indicates clear sky (no cloud cover) to at least 12,000'AGL. This differs from SKC Open Circle in that this square is used with automated reporting stations which cannot detect existence of clouds above 12,000'. SKC indicates a human observer sees no clouds. CLR indicates a reporting station cannot see clouds below 12,000'.
FEW: Open Circle, with line in half icon indicates Few clouds, by definition less than or equal to 1/4 sky.
SCT: Open Circle, with colored quarter icon indicates Scattered clouds, by definition at least 1/4, but less than or equal to 1/2 sky.
BKN: Three-quarters filled Circle icon indicates Broken clouds, by definition more than 1/2 but less than or equal to 7/8ths sky cover.
OVC: Filled Circle icon indicates Overcast clouds. Note that it may still be VFR if cloud altitude is high, and the visibility under the clouds is still good.
OVX: Circle with X indicates no reported cloud information, but reporting is obscured due to poor vertical visibility. The implication is ceiling 0' AGL.
Missing: M indicates no cloud information reported. However, the flight category is indicated by the color of the letter M.
Unknown flight category. Cloud or visibility information is missing or specified in a manner in which flight category cannot be determined.

PIREPs

See also About Pilot Reports.

IcingTurbulence
Note "U" shaped design for Icing: color and vertical lines give clue to severity. Also, Icing PIREP icons lean to the left. Note "^" shaped design for Turbulence: color and number of lines give clue to severity. Also, Turbulence PIREP icons stand straight up.
Negative Icing: Pilot reported absence of icing.
Negative Icing: Pilot reported clear sky (SKC) which implies no icing.
Trace Icing.
Trace to Light Icing.
Light Icing.
Light to Moderate Icing.
Moderate Icing.
Moderate to Severe Icing
Severe Icing
Heavy Icing
Icing reported, but intensity unknown
Negative Turbulence: Pilot reported absence of turbulence.
Smooth to Light Turbulence.
Light Turbulence.
Moderate Turbulence.
Moderate to Severe Turbulence.
Severe Turbulence.
Extreme Turbulence.
Turbulence not reported
   
PIREP without Turbulence or Icing information ("Other")

TAFs

Terminal Aerodrome Forecasts are displayed using the green tinted clock face. Forecasts involve future TIME, hence the clock. Or..., it's a checkmark: remember to CHECK the forecast. Or..., you help me with a better icon?

SIGMETs

SIGMETs are visible as bordered areas on the map, moving the mouse to within the border will change the border line from grey to red or orange, and details of the SIGMET will be provided.

Convective SIGMET Red, because it's a SIGMET. Convective because of the thunderbolt.
Convective Outlook Orange because it's an Outlook, not (yet) a SIGMET. Convective because of the thunderbolt.
Turbulence SIGMET Red, because it's a SIGMET. Turbulence because it uses the severe turbulence "^" symbol.
Icing SIGMET Red, because it's a SIGMET. Icing because it uses the severe icing "U" symbol.

AIRMETs

AIRMETs are visible as bordered areas on the map, moving the mouse to within the border will change the border line from grey to green, yellow or blue, and details of the AIRMET will be provided.

IFR AIRMET (Sierra)Green, well, maybe because you'll not be able to see the ground? The Mountain obscuration looks like a mountain, and the IFR symbol reminds one of haze.
Mountain Obscuration AIRMET (Sierra)
Turbulence AIRMET (Tango) Yellow because perhaps that's how it will make you feel. Turbulence because it uses the moderate turbulence "^" symbol.
Icing AIRMET (Zulu) Blue because it's cold. Icing because it uses the moderate icing "U" symbol.

Winds Aloft

Winds and Temperatures Aloft Forecasts (FB/FD) are displayed using the white balloon. Note that if TAFs and Winds Aloft of displayed at the same time, the TAF icon will be displayed on top, obscuring most of the white balloon. The balloon is a little taller than the TAF icon, so you will still be able to access it. If you're having trouble finding them, turn off TAF display using menu.

Temporary Flight Restrictions

TFRs are visible as bordered areas on the map, moving the mouse to within the border will change the border line from grey to red, and details of the TFR will be provided.

Temporary Flight Restrictions (TFRs) are displayed using the red Do Not Enter symbol.
Formula 1 Racing Stadium TFR
Indy Car Racing Stadium TFR
NASCAR Racing Stadium TFR
Major League Baseball Stadium TFR
National Football League Stadium TFR
NCAA Division I Football Stadium TFR

Airports

Based on VFR Sectionals, as described in the FAA NACO Aeronautical Chart User's Guide 8th Edition [PDF], AvnWx displays airports based on if there is a control tower (blue versus magenta), if there is fuel (four "ears" around the outside of the circle), size and type of runways.

NOTE: Aeronautical charts attempt to show actual runway configurations within the magenta and blue icons. WE DO NOT. For example, AvnWx will always show the same blue icon for all large towered airports, regardless of the number or configuration of runways. This is for convenience, and should not be used for in-flight navigation. If you attempt to use it for actual navigation, please notify your AME about your new mental handicap at your next Medical...

Control Tower Description
With Without
AptBigSvcCT AptBigSvc Public or Military Large Airport (at least one hard surfaced runway > 8069') with Fuel service
AptBigCT AptBig Public or Military Large Airport (at least one hard surfaced runway > 8069') without Fuel service. (Yes, this looks just like the previous icon. Check Airport Details for, um, airport details.
AptHardSvcCT AptHardSvc Public or Military Airport (at least one hard surfaced runway 1500' to 8069') with Fuel service
AptHardCT AptHard Public or Military Airport (at least one hard surfaced runway 1500' to 8069') without Fuel service
AptOtherSvcCT AptOtherSvc Public Airport without hard surfaced runway at least 1500' with Fuel service
AptOtherCT AptOther Public Airport without hard surfaced runway at least 1500' without Fuel service
AptOtherMilSvcCT AptOtherMilSvc Military Airport without hard surfaced runway at least 1500' with Fuel service
AptOtherMilCT AptOtherMil Military Airport without hard surfaced runway at least 1500' without Fuel
AptPvtCT AptPvt Private Airport

Airspaces

AvnWx displays boundaries for only USA Class Bravo, Charlie and Delta airspaces. The colors used match standard VFR Sectionals, but since dashed lines are a bitch to draw on Google Maps, we use thicker lines for class Bravo and Charlie, thinner lines for class Delta (rather than dashed blue lines) -- It's pretty obvious when you see an example:

You can easily see KSJO, a Class C airport in the center. Its thick magenta lines show bondaries for different altitudes for this airspace. Southeast of KSJO is a smaller Class D airport, KRHV. You can see the thin blue circle outlining its airspace. Above it all, are three thicker blue lines which are the outlying boundaries for Class B KSFO San Francisco, which is to the northewest and not shown on this picture. (A keen observer will also see Class D surrounding Moffet Field and part of Palo Alto in the upper right corner of this image.)

Using the maps Terrain background (as above) you can see how some airspaces conform to landmasses, lakeshores, rivers, etc. Alternatively, switch the map background to Satellite and you'll be able to pick out shopping malls, churches or other landmarks to guide you VFR.

Navigational Aids

Based on VFR Sectionals, as described in the FAA NACO Aeronautical Chart User's Guide 8th Edition [PDF], AvnWx displays navaids based on type.

VORVOR
VOR/DMEVOR/DME
VORTACVORTAC
TACANTACAN
VOTVOT
NDBNDB
VORNDB/DME

NEXRAD Radar

NEXRAD colors reflect the intensity (reflectivity) of the echo returns. See discussion at NOAA for details, but as a broad generalization the colors go from blue to green to yellow to red to magenta. Green is generally reported as Trace rainfall, blue would be less. Oranges and red are strong rain, dark reds to magenta are worse.

Surface Analysis Overlay

See detailed description of Surface Analysis Overlay on this help page

Other Icons

Airport/Facility Directory page for the selected location, from the latest FAA A/FD. Complete online version, including Legend and Supplements are available at FAA Aviation System Standards: Digital Airport/Facility Directory
Airport Diagram page for the selected location, from the current FAA Terminal Procedures Publication (updated every 28 days). Complete online version, including Legend and Supplements are available at FAA Aviation System Standards: Digital Terminal Procedures Publication (d-TPP) Clicking this will display the current diagram. Note that the icon itself is not representative of the airport in question -- I think I'm using SFO for the icon.
Warning: Data is known to be old. Because we expect METARs to be issued every hour, if the latest available METAR for a station is more than 90 minutes old, this symbol will be displayed next to the time in the details window. Also shown when TFR data feed is down, such that shown TFRs may be incomplete. Or if a particular TAF was issued more than 12 hours ago (since they should be updated more frequently.) When you see this symbol, mouse over it, and a message will be displayed with details about the warning.

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