IDENTIFYING & COMMUNICATING WEATHER RISK

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08:45am-10:15am John Hampton, The Procter & Gamble Company Roy

1 23rd Annual Schedulers & Dispatchers Conference San Diego, CA January 15 18, 2012 IDENTIFYING & COMMUNICATING WEATHER RISK January 18, :45am-10:15am John Hampton, The Procter & Gamble Company Roy Strasser, Weather Services International (WSI) San Diego, CA January 18, 2012

2 Session Objectives Learn to identify weather phenomena that can significantly impact your flight Understand weather forecasting techniques and limitations of the various phenomena Explore tools that can help you plan around significant weather phenomena Understand the impacts various hazards will have on your operation and passenger comfort Identify significant factors and key points that should be communicated to your passengers 2

3 Aviation Meteorologists & Services ICAO, WMO, EWINS Aviation meteorologists understand and translate weather into aviation impacts, while dispatchers seek ways to mitigate those impacts WMO & EWINS set educational, training and other requirements Private Industry is required by the FAA to meet EWINS standards if producing forecasts for Part 121 or 135 operations Government weather services provide weather information that is mandated by ICAO - generally aligned with the safety of flight Private Industry can provide ICAO-type forecasts plus customized services for individual flight handling or to solve specific operational problems - either safety or economic 3

4 Weather Forecasting Dealing with Uncertainty & Chaos, Think about how extensive the atmosphere is and how few data points are collected Increased computing power coupled with improved NWP modeling has improved deterministic forecasting That said, there s still a lot of uncertainty particularly with significant small scale weather phenomenon, e.g. TS, TB, IFR ceilings and visibilities Until forecast accuracy achieves a very high level, the role of the meteorologist is to convey probabilistic results into the best deterministic answer 4

5 Weather Phenomenon Low Ceilings and Visibilities CAUSES Fog Radiation: Upward flux of radiation from the earth into the atmosphere cools the surface Advection: Warm moist air flowing over a cooler surface Upslope: Warm moist air flowing from lower to higher elevations adiabatic cooling Frontal Proximity Overrunning: Warm air flowing up and over cooler, more dense air below Precipitation Heavier precipitation reduces visibility Precipitational fog Stratiform precipitation versus showers 5

6 Weather Phenomenon Low Ceilings and Visibilities WHAT TO LOOK FOR Fog Radiation: Clear or clearing skies, very light winds and decreasing air temperature/dew point spread Advection: Look for dew points temperatures above the surface temperatures such as cold ocean or lake waters, snow covered or frozen ground Upslope: Moist air flowing into higher elevations such as the easterly winds into the High Plains up to the Continental Divide Frontal Proximity North of approaching warm fronts Shallow cold fronts expected to stall to the south of your destination airport Precipitation Use convective indices to test atmospheric stability Look for areas where extensive light precip is expected 6

7 Impacts on the National Airspace System (NAS) Ground Delay Programs (GDP) Airport Specific Designed to regulate arrivals based on an established ACCEPTANCE RATE due to current airport conditions USEFUL WEATHER PRODUCTS Surface Analysis / Sig Weather Charts, Graphical AIRMETs and SIGMETs Text Weather METARs and TAFs Flight delay information (FAA Website) National Airspace System (FAA Website) EDCT (+/- 5 Min) 7

8 Graphical Forecast Surface Weather Depiction & Low Level Sig Wx Progs 8

9 Graphical AIRMET Display Ceiling and Visibility 9

10 Flight Delay Information 10

11 Ground Delay Programs National Airspace System Status 11

12 Ground Delay Programs (GDP) ATCSCC Advisory 12

13 Ground Stop Programs (GSP) Weather below approach Minimums November 10, :00 Z Route: KJFK IATA ICAO Airport Name City State Country JFK New York New York United States KJFK John F Kennedy Intl Latitude Longitude 73 46' 44" 40 38' 23" N W METARs: KJFK Z 03004KT 0SM R04R/0700V1000FT FG BKN001 BKN045 13/13 A2990 RMK AO2 SFC VIS 1/4 SLP124 T KJFK Z 35004KT 0SM R04R/0600V1800FT FG VV001 13/12 A2992 RMK AO2 SFC VIS 1/4 KJFK Z 01003KT 0SM R04R/1000V2200FT FG VV002 13/12 A2993 RMK AO2 SFC VIS 1/4 KJFK Z 34003KT 0SM R04R/3500VP6000FT FG VV002 13/12 A2993 KJFK Z 02004KT 0SM R04R/0800V4000FT FG BKN001 BKN085 BKN250 12/12 A2994 KJFK Z 01003KT 0SM R04R/0700V1600FT FG VV001 12/12 A2993 RMK AO2 SFC VIS 1/4 SLP135 T KJFK Z 00000KT 0SM R04R/1000V1200FT FG VV001 12/12 A2993 RMK AO2 SFC VIS 1/4 TAFs: KJFK Z 1014/1118 VRB03KT 1SM BR SCT004 BKN007 TEMPO 1014/1016 1/4SM -DZ FG OVC004 FM KT 3SM -SHRA BR SCT010 OVC020 FM KT P6SM BKN025 OVC050 FM KT P6SM SCT030 BKN050 FM KT P6SM BKN050 FM G21KT P6SM SCT060 SCT100 FM G32KT P6SM SCT050 13

Computer Generated Station Forecasts GFS Forecasts http://charlie.wxcaster.

14 Computer Generated Station Forecasts GFS Forecasts LAMP Forecasts 14

15 Weather Phenomenon Deicing / Ground Contamination WINTER PRECIP TYPES Freezing FZDZ, FZRA FZFG (hoar frost) IC (ice crystals) Frozen PL (known as PE int l) SG GS (snow pellets) SN UP (unknown precip) Mixed RASN, RAPL Many other combos 15

16 Weather Phenomenon Deicing / Ground Contamination Wet snow versus dry Wet snow occurs with shallow freezing layers and when lowest layer is warm; up to 4oC Increases takeoff roll, slush correction applied Runway, taxiway plowing / deicing Triggered when braking action becomes poor Requires temporarily closure of runways and taxiways; could lead to the airport being closed Heavier snow/ice and drifting snow exacerbate the situation Ground Service work force becomes less effective Ramp activity slowed by very cold temperatures Maneuvering ground equipment in snow and ice becomes more difficult Airport and support work force have higher rates of absenteeism 16

17 Weather Phenomenon Deicing / Ground Contamination DEICING OPERATIONS Type I Propylene-based fluid Heated fluid used for snow & ice removal Type II and III Degrees of thickening agents used, type II is thicker than type III Regional and business aircraft now using more type III Type IV Glycol-based fluid Anti-icing application applied to prevent snow/ice build up More effective if applied within a heated hanger (also better environmentally) Hold Over and Allowance Tables Allowance times versus Hold Over times No HOT guidelines provided for moderate or heavy FZRA, heavy SN or GR 17

18 Weather Phenomenon Deicing / Ground Contamination HOLDOVER & ALLOWANCE GUIDELINES Dictates the length of time deicing applications will be effective In general, moderate freezing or frozen precip has a zero hold over time Ice Pellets alone or mixed with other precip types create a zero allowance time 18

19 Weather Phenomenon Deicing / Ground Contamination Observation & Forecasting Tools METARs and TAFs SNOWTAM GG EDZZ EDDKYDYX SWED0012 EDDK (SNOWTAM 0012 A) EDDK B) C) 14L F) 2/2/2 G) 30/30/40 H) 5/5/5 C) 14R F) 5/5/5 G) 30/30/40 H) 9/9/9 C) 07 F) 5/5/5 G) 40/30/30 H) 9/9/9 R) WET S) T) SNOW REMOVAL IN PROGRESS) METARs indicate observed precip types/intensities and they may contain RMKS about snow accumulation and other pertinent weather information TAFs provide the same weather elements as Metars but with onset & offset timing and no accumulation information SNOWTAMs Provide information regarding snow conditions on runways & taxiways Precip type radar imagery Differentiates precip type by using a blend of observed surface temperatures and high fidelity NWP Not a perfect 1:1 coloration but a very good proxy Dual polarity radars actually detect different precip types fully deployed U.S. by mid

20 Winter Storms Polar Front and Four Corners Low Polar Air Mass Colliding with warm, moist Sub-Tropical Air Mass 20

21 Winter Storms Upper Level Lows Best seen at the 500mb or 700mb levels. Have been responsible for unexpected heavy snows. Warm moist air rises from the Gulf of Mexico and drops into the storm system behind the surface cold front. 21

22 Winter Storms 22

23 Weather Phenomenon Turbulence WHAT IS TURBULENCE? Rapid changes in atmospheric wind speeds and direction that cause irregular motions of an aircraft in flight These erratic velocities in the flow can occur in a lot of different situations and lead to passengers & crew discomfort and possible injury 23

24 Weather Phenomenon Turbulence JET STREAM Profile of a jet core Often near the tropopause Greatest shearing found above and north of the jet core Two main jet streams: Polar and Subtropical jets Jet streams migrate north and south seasonally Split or divergent flow regions Turbulence usually located from the split flow outward Can produce moderate and even severe turbulence in these zones Also favorite place for thunderstorm development Anticyclonic (clockwise) curvature The intensity of the turbulence will increase as the curvature and wind speeds increase 24

25 Weather Phenomenon Turbulence JET INDUCED TURBULENCE Vertical and Horizontal Shearing Strongest horizontal shearing found north of the jet core, around high-speed bubbles, and at the nose of the jet (Rule of thumb: >25kts per 100 miles) Strongest vertical wind shears mostly found above the jet core (Rule of thumb: >06kts per 1,000 feet) North of cutoff lows and near the Comma tails Shearing and stretching zones 25

26 Weather Phenomenon Turbulence MESO SCALE CONVECTIVE SYSTEMS (MCS) Significant turbulence often noted north and west of an MCS This is due to the enhancement of the upper level winds 26

27 Weather Phenomenon Turbulence MOUNTAIN WAVE ACTIVITY (Vertically Propagated) Moderate winds nearly perpendicular to mountain range Should have little or no vertical shear within a marginally stable atmosphere Steep terrain profiles preferred to downwind side of mountain range Well developed vertical waves with severe turbulence can reach altitudes above FL600 Satellite imagery often shows a narrow dry slot to the leeside with a mature wave 27

28 Weather Phenomenon Turbulence OBSERVATION & FORECAST TOOLS High resolution satellite imagery can help identify suspect or known areas of turbulence However, must have moisture present to see the effects of any turbulence Useful in filling in gaps in PIREP coverage 28

29 Weather Phenomenon Turbulence OBSERVATION & FORECAST TOOLS Graphical Turbulence Guidance (GTG) product Uses a set of integrated turbulence algorithms to predict CAT over the CONUS region Does not predict convectively induced turbulence (CIT) GTG was developed at NCAR and is considered an operational product available on the AWC website Output indicated in levels of severity 29

30 Weather Phenomenon Turbulence OBSERVATIONA L & FORECAST TOOLS NWS AIRMET Tango Issued every 6 hours for areas of LGT MDT turbulence, for all aircraft types Areas are often very large, but good for general heads up NWS SIGMET Issued as required for severe turbulence only, for all aircraft types AIRMETs and SIGMETs issued as either graphical or textual products 30

31 Aviation Weather Center Turbulence 31

32 Aviation Weather Center SIGMET/AIRMET, Turbc High & Turbc Low Selected 32

33 Vertical Shear Factor Indicated on Computerized Flight Plans CPT FREQ FLT S WIND TP TDV MH TAS MCS ZDST DSTR ZT GRS AWY CT ETA ATA ETR FU EFR AFR FF/ NM/L CVG P DCT KENLN P DCT HYK P DCT VXV P DCT SPA P DCT

34 Weather Phenomenon Inflight Icing CAUSES Liquid water droplets are found in clouds that are below freezing but lack icing nuclei to start crystallization Greatest ice accretion occurs between 0 C and -10 C It is rare to get icing with temperatures below -25 C TYPES Rime icing (mostly found below -15 C) Most common type Smaller droplets that rapidly freeze to trap bubbles of air Clear icing (mostly found between 0 C to 10 C) Mixed (found below 0 C) Can be the most dangerous type of icing because of irregular shapes 34

35 Weather Phenomenon Inflight Icing FORECAST TOOLS CIP (Current Icing Potential) Automatically combines data from multiple sources e.g. satellites, radars, surface and upper air obs, NWP, and PIREPs to nudge forecasts FIP (Forecast Icing Potential) Initialized with CIP and based on information from the RUC model CIP/FIP Products do not provide icing severity information Not recommended for MEL issues Only shows freezing probabilities 35

36 Weather Phenomenon Inflight Icing FORECAST PRODUCTS NWS AIRMET Zulu Issued for LGT MDT icing, for all aircraft types Issued every 6 hours, amended as necessary Contains freezing level information Areas are often very large Issued as a graphical and textual product NWS SIGMETs Issued for severe icing, for all aircraft types Issued as a graphical and textual product ETOPS Icing charts Assists dispatchers to assess icing penalty and fuel usage Calculated using RH and temperature at FL100 (700mb level) 36

37 Graphical AIRMET Display Icing and Freezing Level 37

38 Weather Phenomenon Thunderstorms REQUIREMENTS Moisture Moisture is a thunderstorm s fuel Layer should be 4,000-5,000ft deep Lifting Mechanism Surface wind convergence found with boundaries such as with fronts, troughs or dry lines Upsloping terrain Instability Instability is caused when relatively warm air is located below a cooler layer An unstable air mass seeks to overturn itself Many ways to measure Lifted Index (LI), K-Index 38

39 Weather Phenomenon Thunderstorms TYPES Airmass Short-lived an hour or less Nearly impossible to predict precise location Coverage tends to be mostly scattered causing minor en route deviations Steady-State or Forced Mesoscale Convective Systems (~18 hours) Squall Lines (~3-6 hours) Activity focused along boundaries Can cause major disruptions to airport and en route airspace operations Nocturnal Development and instability takes place after dark in warm air advection zones 39

40 Weather Phenomenon Thunderstorms CHARACTERISTICS Outflow Boundaries Intersecting boundaries Squall line jumps High-based CBs bases Usually found west of the divide Dry microbursts, excess lightning Train- echoes or Training Prolonged terminal area events Associated with stalling cold or stationary fronts and parallel wind flow aloft 40

41 Weather Phenomenon Thunderstorms FORECAST PRODUCTS Collaborative Convective Forecast Product (CCFP) Initial forecast comes from AWC which is then adjusted based on collaborative feedback from CWSUs and private sector (vendors, airline mets) Seasonal product from April through October 6-8 hour forecasts updated every 2 hours NWS Convective SIGMETs 1 hour forecasts with 1 hour outlook, updated hourly Can drive up dispatcher workload through repeated updates without links to previous convective areas Integrated Tools like CWIS, CoSPA, Fusion and Flight Explorer combine normally disparate convective displays into one display 41

42 Flow-Constrained Area (FCA) REDUCED ABILITY TO ROUTE FLIGHTS THROUGH LINES OR LARGE AREAS OF THUNDERSTORMS USEFUL WEATHER PRODUCTS Surface Analysis / Sig Weather Charts Radar Composite NAS Website EDCT (+/- 5 Min) 42

43 Severe Weather Avoidance Program (SWAP) Plan SWAP ZNY KEWR D SBY ZNY TRW KEWR..COL..SBY FL100 FL There is a SWAP route published by NY ARTCC for EWR Departures via SBY VOR. The route is EWR direct COL VOR Direct SBY VOR thence Destination for all flights from FL 100 to FL410 from 1845Z to 2100Z SWAP ZFW KDFW R IAH ZHU TRW KDFW..ACT..FST..AUS..IAH FL000 FL There is a SWAP route published by ZFW ARTCC for DFW departures to IAH. The route is DFW direct ACT direct FST direct AUS direct IAH for FL000 (SFC) to FL 410 beginning at 1845Z and ending at 2100Z 43

Weather Phenomenon Volcanic Ash EFFECTS Reduces engine performance; can cause flame out Abrades all leading edge surfaces Ash fallout very difficult to clean up

VA INFORMATION VAAC (Volcanic Ash Advisory Centers) Issue VAAS (Volcanic Ash Advisory Statements) ASHTAMS Issued by FIR region (Note: This is not a black & white

44 Weather Phenomenon Volcanic Ash EFFECTS Reduces engine performance; can cause flame out Abrades all leading edge surfaces Ash fallout very difficult to clean up When mixed with water can corrodes metal surfaces (becomes Sulfuric Acid) Ash encountered at concentrations above 2 x 10-3 g/m3 may cause engine or airframe damage VA INFORMATION VAAC (Volcanic Ash Advisory Centers) Issue VAAS (Volcanic Ash Advisory Statements) ASHTAMS Issued by FIR region (Note: This is not a black & white picture) GREEN Volcano is dormant YELLOW Volcano is restless; Or eruption possible ORANGE Volcano erupting; Or is imminent RED Significant eruption Ongoing or expected 44

45 Weather Phenomenon Ozone Almost all ozone (O3) is found above the tropopause The tropopause is lower over high latitudes and in the vicinity of low pressure areas; the converse is also true FAR states the FAA s position on ozone, though requirements are based on statistical information not actual ozone obs or forecasts Flight is not permitted at or above FL320 when ozone concentrations exceed 0.25ppm 45

46 Weather Phenomenon Solar Activity Sun spots are a source of solar flare activity Solar flares suddenly release tremendous amounts of magnetic energy Solar activity cycles Averages to an 11-year cycle and connected to the Earth s climate SOLAR HAZARDS & EFFECTS Radiation passengers & crew hazard (S events) Geomagnetic storms (G events) Can disrupt communications, particularly satellite navigation systems Radio blackouts (R events) Switching to VHF can overcome some less significant activity 46

47 Weather Phenomenon Solar Activity SOURES FOR SOLAR INFORMATION NOAA s Space Weather Prediction Center (SWPC) SWPC places all solar events into three categories: R for Radio Interference S for Solar Radiation G for Geomagnetic SWPC Alerts are normalized to fit into a range of 1 5 Level 1 events are considered minor while level 5 events are extreme Significant impacts start to occur at level 3 The SWPC website provides users with an easy to read table describing activity over the last 24 hours and what is expected. During active periods the top of the webpage usually contains a Top News Story section that further describes the solar event 47

48 Communicating With The Passengers Develop a relationship to communicate freely. Be proactive in alerting your passengers to weather impacting their flight, especially if timing will be affected. Stay ahead of your schedule. Check trends and forecasts 2-3 days in advance. Give your passengers time to adjust their plans. Use common terminology to explain the situation. Be clear regarding delays and EDCTs. If you miss the EDCT, you might experience significant additional delays. Check ground conditions at the destination the trip doesn t end when the airplane lands. 48

49 HELPFUL RESOURCES Flight Crew Handling Agent Meteorologists NBAA GA Desk Subscribe to receive NAS warnings and alerts Provide your flight schedule daily File your flight plans well in advance with ETD 30 min before desired take off time if FCA or GDP expected Request their help in resolving issues when timing is critical 49

50 NBAA GA Desk Contact NBAA s GA Desk for pricing and other details: Tel: (540) gadesk@nbaa.org Web: 50

51 USEFUL WEBSITES FLIGHT DELAY INFORMATION NAS STATUS EDCT Look Up AVIATION WEATHER GFS FORECAST Localized Aviation MOS Product (LAMP) 51

52 Abbreviations and Acronyms not spelled out within the presentation AWC: CAT: CoSPA: CWIS: EWINS: FROPA: FZDZ: FZFG: FZRA: GS: HOT: IC: ICAO: MCS: NWP: QPF: SN: TB: TS: USGS: WMO: Aviation Weather Center (NOAA / NWS) Clear Air Turbulence Consolidated Storm Predication for Aviation Corridor Weather Information System Enhanced Weather INformation Services FROntal Passage Freezing Drizzle Freezing Fog Freezing Rain Small Hail or Snow Pellets Hold Over Tables Ice Pellets International Civil Aviation Organization Meso scale Convective System Numerical Weather Prediction Quantitative Precipitation Forecast Snow Turbulence Thunderstorms United States Geological Society World Meteorological Organization 52

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Issue of SIGMET/AIRMET warning

Issue of SIGMET/AIRMET warning 1 Presentation Objectives After this presentation session you will be able to: Warn for Hazardous weather phenomena using the correct ICAO coding with regards to SIGMET/AIRMET