Aviation Weather Services, Advisory Circular 00-45F, Revision 1 to 17,000 feet and Flight Levels above 17,000 feet. The ADDS web site allows for access to every other altitude (1,000 FT, 3,000 FT, 5,000 FT, etc...). However, all altitudes can be accessed by use of the Flight Path Tool on the ADDS site.
Icing PIREPs are plotted on a single altitude graphic if the PIREP is within 1,000 feet of the selected altitude and has been observed within 75 minutes of the chart's valid time. On the CIP Max graphics, PIREPs for all altitudes (i.e. 1,000 feet MSL to FL300) are displayed. However, negative reports of icing are not plotted on the CIP Max products in an effort to reduce clutter.
The PIREP legend is located on the bottom of each graphic.
9.3.2.1 Icing Probability The Icing Probability product (Figure 9-12) displays, at a single altitude, the probability of icing.
Probabilities range from 0% (no icing expected) to 85% or greater (nearly certain icing.)
By FAA policy CIP is a Supplementary Weather Product for enhanced situational awareness only and must be used with one or more primary products (safety decision) such as an AIRMET or SIGMET (see AIM 7—1—3).
Probability of icing at 3000 ft. MSL Analysis valid 1500 UTC Mon 27 Nov 2006 terrain 5 25 35 45 55 65 75 g Negative 1) Trace-Light \ Light-Maderate 'I Maderate-Severa (percent) Icing PIREP Symbals (J Trace Ll Light ' Moderate I Savare Figure 9-12. CIP Icing Probability (3,000 feet MSL) Example AC 00-45F (July 2008) Section 9: Supplementary Products Page 9-14
Aviation Weather Services, Advisory Circular 00-45F, Revision 1 "Cool" colors represent low probabilities and "warm" colors represent higher probabilities.
Probabilities do not reach 100% because the data used to determine the probability of icing cannot diagnose, with absolute certainty, the presence of icing conditions at any location and altitude. White regions indicate that the probability of icing is zero. Brown regions indicate where higher-elevation terrain extends above the altitude of the particular graphic.
9.3.2.2 Icing Probability -- Maximum The Icing Probability - Maximum graphic (Figure 9-13) displays the probability of icing at all altitudes from 1,000 feet MSL to FL300. Probabilities range from 0% (no icing expected) to 85% or greater (nearly certain icing.)
dy FAA policy CIP is a Supplementary Weather Product for enhanced situational awareness only and must be used mith one or more primary products (safety decision) such as an AIRMET or SIGMET (see AIM 7-1-3).
Maximum icing probability (1000 ft. MSL to FL300) Analysis valid 1600 UTC Mon 27 Nov 2006 25 45 65 75 I Trace-Light Vp Light-Moderate _I Moderate-Savera (percent) cing PIREP Symbals W Trace Ly Light ly/ Maderate Lyl Severe Figure 9-13. CIP Icing Probability - Max Example "Cool" colors represent low probabilities and "warm" colors represent higher probabilities.
Probabilities do not reach 100% because the data used to determine the probability of icing AC 00-45F (July 2008) Section 9: Supplementary Products Page 9-15
Aviation Weather Services, Advisory Circular 00-45F, Revision 1 cannot diagnose, with absolute certainty, the presence of icing conditions at any location and altitude. White regions indicate the probability of icing is zero.
9.3.2.3 Icing Severity The Icing Severity product (Figure 9-14) depicts, at a single altitude, the intensity of icing expected at locations where the Icing Probability product depicts possible icing. Icing intensity is displayed using standard icing intensity categories: trace, light, moderate and heavy.
By FAA policy CIP is a Supplementary Weather Product for enhanced situational awareness only and must be used with one or more primary products (safety decision) such as an AIRMET or SIGMET (see AIM 7-1-3).
Icing severity at 3000 it. MSL Analysis valid 1500 UTC Mon 27 Nov 2006 terrain None Trace Light Moderate Heavy g Negative 4J Trace-Light W Light-Maderate 1| Moderate-Savare Icing PIREP Symbals W Trace Ly) Light / Noderate Ly severe Figure 9-14. CIP Icing Severity (3,000 feet MSL) Example The lightest blue color represents trace icing. As the blue-color shades become darker, the icing intensity increases. The darkest blue color represents heavy icing. White regions indicate where no probability of icing exists and, therefore, no intensity is necessary. Brown regions indicate where higher-elevation terrain extends above the altitude of the particular graphic.
AC 00-45F (July 2008) Section 9: Supplementary Products Page 9-16
Aviation Weather Services, Advisory Circular 00-45F, Revision 1
9.3.2.4 Icing Severity -- Maximum The Icing Severity - Maximum product (Figure 9-15) displays the intensity of icing at all altitudes from 1,000 feet MSL to FL300. Icing intensity is displayed using standard icing intensity categories: trace, light, moderate and heavy.
By FAA policy CIP is a Supplementary Weather Product for enhanced situational awareness only and must be used with one or more primary products (safety decision) such as an AIRMET or SIGMET (see AIM 7—1-3).
Maximum icing severity (1000 ft. MSL to FL300) Analysis valid 1600 UTC Mon 27 Nov 2006 None Trace Light Moderate Heavy 1]] Trace-Light V Light-Moderate _I Moderate-Savare Icing PIREP Symbale W Trace Ly Light H' Mederate severe Figure 9-15. CIP Icing Severity - Max Example The lightest blue color represents trace icing. As the blue color shades become darker, the icing intensity increases. The darkest blue color represents heavy icing. White regions indicate where no probability of icing exists and, therefore, no intensity is necessary.
9.3.2.5 cing Severity - Probability > 25% The Icing Severity - Probability > 25% product (Figure 9-16) depicts, at a single altitude, where a 26 to 100 percent probability exists for the indicated icing intensity. Icing intensity is displayed using standard icing intensity categories: trace, light, moderate and heavy.
AC 00-45F (July 2008) Section 9: Supplementary Products Page 9-17
Aviation Weather Services, Advisory Circular 00-45F, Revision 1 ly FAA policy CIP is a Supplementary Meather Product tor enhanced situational awareness only and must b ised with one or more primary products (safety decision) such as an AIRMET or SIGMET (see AIM 7-1-3) Icing severity (prob>25%) at 3000 ft. MSL Analysis valid 1500 UTC Mon 27 Nov 2006 terrain None <25% Trace Light Moderate Hedyy ø Negative 4J Trace-Light W) Light-Moderate I Moderate-Savare Icing PIREP Symbols W Trace Ly Light Y/ Severa Figure 9-16. CIP Icing Severity Probability >25% Example The lightest blue color represents trace icing. As the blue color shades become darker, the icing intensity increases. The darkest blue color represents heavy icing. White regions indicate where no probability of icing exists and, therefore, no intensity is necessary. Brown regions indicate higher-elevation terrain extending above the altitude of the particular graphic. A gray color is used to mask the intensity pixels where the probability of icing is 25% or less.
9.3.2.6 Icing Severity - Probability > 25% - Maximum The Icing Severity - Probability > 25% - Maximum product (Figure 9-17) depicts, at all altitudes from 1,000 feet MSL to FL300, where the probability of the indicated icing intensity is 26 to 100 percent. Icing intensity is displayed using standard icing intensity categories: trace, light, moderate, heavy.
AC 00-45F (July 2008) Section 9: Supplementary Products Page 9-18
Aviation Weather Services, Advisory Circular 00-45F, Revision 1 By FAA policy CIP is a Supplementary Weather Product for enhanced situational awareness only and must be used with one or more primary products (safety decision) such as an AIRMET or SIGMET (see AIM 7—1-3).
Maximum icing severity (prob>25%) (1000 ft. MSL to FL300) Analysis valid 1700 UTC Mon 27 Nov 2006 None <25% Trace Light Moderate Heavy
4) Trace-Light WiLight-Moderate 1) Moderate-Savare Icing PIREP Symbols W Traca Ll Light ' Moderate Yul Severa Figure 9-17. CIP Icing Severity Probability >25% Example The lightest blue color represents trace icing. As the blue color shades become darker, the icing intensity increases. The darkest blue color represents heavy icing. White regions indicate where no probability of icing exists and, therefore, no intensity is necessary. A gray color is used to mask the intensity pixels where the probability of icing is 25% or less.
9.3.2.7 Icing Severity - Probability > 50% The Icing Severity - Probability > 50% product (Figure 9-18) depicts, at a single altitude, where the probability of the indicated icing intensity 51 to 100 percent. Icing intensity is displayed using standard icing intensity categories: trace, light, moderate and heavy.
AC 00-45F (July 2008) Section 9: Supplementary Products Page 9-19
Aviation Weather Services, Advisory Circular 00-45F, Revision 1 By FAA policy CIP is a Supplementary Weather Product for enhanced situational awareness only and must be used with one or more primary products (safety decision) such as an AIRMET or SIGMET (see AIM 7-1-3).
Icing severity (prob>50%) at 3000 ft. MSL Analysis valid 1500 UTC Mon 27 Nov 2006 terrain None <50% Trace Light Moderate Heavy ga Negative LJ Trace-Light W Light-Moderate | Moderate-Severe Icing PIREP Symbals W Trace Le Light HI Madsrate If Savara Figure 9-18. CIP Icing Severity Probability > 50% Example The lightest blue color represents trace icing. As the blue color shades become darker, the icing intensity increases. The darkest blue color represents heavy icing. White regions indicate where no probability of icing exists and, therefore, no intensity is necessary. Brown regions indicate where higher-elevation terrain extends above the altitude of the particular graphic. A gray color is used to mask the intensity pixels where the probability of icing is 50% or less.
9.3.2.8 Icing Severity - Probability > 50% - Maximum The Icing Severity - Probability > 50% - Maximum product (Figure 9-19) depicts, at all altitudes from 1,000 feet MSL to FL300, where the probability of the indicated icing intensity is 51 to 100 percent. Icing intensity is displayed using standard icing intensity categories: trace, light, moderate and heavy.
AC 00-45F (July 2008) Section 9: Supplementary Products Page 9-20
Aviation Weather Services, Advisory Circular 00-45F, Revision 1 By FAA policy CIP is a Supplementary Meather Product for enhanced situational awareness only and must be used with one or more primary products (safety decision) such as an AIRMET or SIGMET (see AIM 7-1-3).
Maximum icing severity (prob>50%) (1000 fl. MSL to FL300) Analysis valid 1700 UTC Mon 27 Nov 2006 None <50% Trace Light Moderate Heavy Wi Trace-Light N Light-Moderate I Moderate-Savara leing PIREP Symbols W Trace Yu Light 4) Moderate I Severa Figure 9-19. CIP Icing Severity Probability > 50% - Max Example The lightest blue color represents trace icing. As the blue color shades become darker, the icing intensity increases. The darkest blue color represents heavy icing. White regions indicate where no probability of icing exists and, therefore, no intensity is necessary. A gray color is used to mask the intensity pixels where the probability of icing is 50% or less.
9.3.2.9 Icing Severity plus Supercooled Large Droplets (SLD) The Icing Severity plus Supercooled Large Droplets (SLD) product (Figure 9-20) depicts, at a single altitude, the intensity of icing expected as well as locations where a threat for SLD exists.
SLD is defined as supercooled water droplets larger than 50 micrometers in diameter. These size droplets include freezing drizzle and/or freezing rain aloft. SLD, which are outside the icing AC 00-45F (July 2008) Section 9: Supplementary Products Page 9-21
Aviation Weather Services, Advisory Circular 00-45F, Revision 1 certification envelopes (FAR Part 25 Appendix C), can be particularly hazardous to some aircraft.
Icing intensity is displayed using standard icing intensity categories: trace, light, moderate and heavy.
ly FAR policy LIP is a Supplementary neather Product tor enhanced situational avareness only and must bi ised with one or more primary products (safety decision) such as an AIRMET or SIGMET (see AM 7-1-3) Icing severity at 3000 ft. MSL Analysis valid 1800 UTC Mon 27 Nov 2006 SLD threat terrain None Trace Light Moderate Heavy ø Negative LJ Trace-Light / Light-Moderate I Maderate-Savare cing PIREP Symbals W Trace Let Light If Moderate Kyl severe Figure 9-20. CIP Icing Severity plus Supercooled Large Droplets (SLD) Example The lightest blue color represents trace icing. As the blue color shades become darker, the icing intensity increases. The darkest blue color represents heavy icing. White regions indicate where no probability of icing exists and, therefore, no intensity is necessary. Brown regions indicate where higher-elevation terrain extends above the altitude of the particular graphic.
Locations where a threat for SLD exists are depicted with red hatching.
AC 00-45F (July 2008) Section 9: Supplementary Products Page 9-22
Aviation Weather Services, Advisory Circular 00-45F, Revision 1
9.3.2.10 Icing Severity plus Supercooled Large Droplets (SLD) - Maximum The Icing Severity plus Supercooled Large Droplets (SLD) product (Figure 9-21) depicts at all altitudes, between 1,000 feet MSL and FL300, the intensity of icing expected as well as locations where a threat for SLD exists.
SLD is defined as supercooled water droplets larger than 50 micrometers in diameter. These size droplets include freezing drizzle and/or freezing rain aloft. SLD, which are outside the icing certification envelopes (FAR Part 25 Appendix C), can be particularly hazardous to some aircraft.
By FAA policy CIP is a Supplementary Weather Product for enhanced situational awareness only and must be used mith one or more primary products (safety decision) such as an AIRMET or SIGMET (see AIM 7—1—3).
Maximum icing severity (1000 ft. MSL to FL300) Analysis valid 1500 UTC Mon 27 Nov 2006 SLD threat None Trace Light Moderate Heavy I Trace-Light W Light-Moderate I Moderate-Savare cing PIREP Symbols W Trace Ly Light * Moderate yul Severe Figure 9-21. CIP Icing Severity plus Supercooled Large Droplets (SLD) - Max Example The lightest blue color represents trace icing. As the blue color shades become darker, the icing intensity increases. The darkest blue color represents heavy icing. White regions indicate AC 00-45F (July 2008) Section 9: Supplementary Products Page 9-23
Aviation Weather Services, Advisory Circular 00-45F, Revision 1 AC 00-45F (July 2008) Section 9: Supplementary Products Page 9-24 where no probability of icing exists and, therefore, no intensity is necessary. Locations where a threat for SLD exists are depicted with red hatching.
9.3.3 Strengths and Limitations
9.3.3.1 Strengths The CIP product suite is updated hourly and provides a diagnostic tool to assist in determining the probability for icing, the intensity of icing and the threat for SLD.
9.3.3.2 Limitations Actual icing severity may be different than what is depicted on the CIP graphics and plotted PIREPS because:
Different aircraft types experience different severities of icing in the same atmospheric environments. Severity definitions are currently pilot-based and thus are a function of the aircraft type, flight phase (takeoff/landing, cruise, etc.), aircraft configuration, as well as the pilot’s experience and perception of the icing hazard.
Assessing the amount and drop size of supercooled liquid water (SLW) in the atmosphere is difficult.
The Icing Severity products depict the severity of the meteorological icing environment and not the resultant icing that may occur on the aircraft.
9.3.4 Uses The CIP Icing Probability product can be used to identify the current three-dimensional probability of icing.
The CIP Icing Severity product can be used to determine the intensity of icing. The CIP Icing Severity – Probability > 25% or Probability > 50% depicts the probability of a given intensity of icing occurring.
Finally the Icing Severity plus SLD product can help in determining the threat of SLD which is particularly hazardous to some aircraft.
Icing PIREPs are plotted on single altitude graphics if the PIREP is within 1,000 feet of the graphic’s altitude and has been observed within 75 minutes of the chart’s valid time. On CIP Max product, PIREPs for all altitudes (i.e. 1,000 feet MSL to FL300) are displayed. However, negative reports of icing are not plotted on the CIP Max product in an effort to reduce clutter.
The PIREP legend is located on the bottom of each graphic.
Aviation Weather Services, Advisory Circular 00-45F, Revision 1 AC 00-45F (July 2008) Section 9: Supplementary Products Page 9-25
9.4 Forecast Icing Potential (FIP) The Forecast Icing Potential (FIP) provides a three-dimensional forecast of icing potential (or likelihood) using numerical weather prediction model output (Figure 9-17). The FIP product suite is automatically generated with no human modifications. It may be used as a higher resolution supplement to AIRMETs and SIGMETs but is not a substitute for them. It is authorized for operational use only by meteorologists and dispatchers. The forecast area covers the 48-contiguous states, much of Canada and Mexico and their respective coastal waters.
9.4.1 Issuance The FIP is issued every hour and generates hourly forecast for 3 hours into the future. For example, forecasts issued at 1300Z would be valid for 1400Z, 1500Z and 1600Z. Six-, 9-, and 12-hour forecasts are issued every three hours beginning at 00Z. For example, a forecast suite issued at 0300Z would have valid times at 0900Z, 1200Z and 1500Z respectively. The product is issued by the Aviation Weather Center (AWC) and is available through the Aviation Digital Data Service (ADDS) web site at: http://adds.aviationweather.noaa.gov/icing/icing_nav.php.
9.4.2 Content The FIP forecasts the likelihood of icing from super-cooled liquid water droplets. The likelihood field ranges from 0 (no icing) to 100 (icing likely). The scale depicts likelihood of icing using “cool” and “warm” colors, with warmer colors indicating a higher likelihood of icing. Regions depicted in white indicate zero icing potential according to the CIP. Brown regions indicate areas of terrain.
The scale is not calibrated as a true probability value. It does, however, have value in pointing out differences in the likelihood of encountering icing at a given location. For example, a value of 70 does not indicate there is a 70 percent chance of encountering icing. However, when comparing it to other higher or lower values will indicate if there is a greater or lesser likelihood of encountering icing. No information is provided as to the severity of icing and none should be inferred. FIP output is available for 1,000 foot vertical intervals. ADDS displays every third level except on the Flight Path Tool which provides access to all levels.