1. NWS Pocatello Aviation Forecast Operations Gary Wicklund Aviation Meteorologist

2. My 42 Year Forecast Method

3. Forecast Office Overview 5 Lead Forecasters 5 Journey Forecasters 3 Hydro-Met.Techs. / Intern Our Responsibilities include: Public Forecasts and Warnings Hydrologic Wildfire and Land Management Avalanche Guidance Aviation Our Operational Staff includes: Responsible for southeast Idaho

4. Aviation Operations Overview  Terminal Aerodrome Forecasts (TAFs) Four times a day and updated as needed Pocatello Idaho Falls Sun Valley Burley What We Do…  Forecast Office Support, as needed, to: Boise Salt Lake City

5. Weather Fundamentals Circulation: Earth’s orbit and axis tilt create our seasons

6. Weather Fundamentals Air rises higher at Equator than poles

7. Weather Fundamentals Different air masses which affect North America, as well as other continents, tend to be separated by frontal boundaries Source regions of global air masses (cA, mP, etc.)

8. Weather Fundamentals

9. Clouds and stability –Stable air mass -- flat cloud development –Unstable air mass -- vertical growth Weather Fundamentals

10. Cloud Classification Stratus: “layered”, “sheetlike” Cumulus: “puffy”, “heap” Nimbus: “rain cloud” or “violent rain” Cirrus: “wispy” type of cloud Weather Fundamentals

11. Low Cloud Type - Cumulus “Cotton ball” clouds The top of the cloud generally denotes the limit of the rising air. Clouds are “detached”, with blue sky between each cloud Weather Fundamentals

12. Low Cloud Type – Fair Weather Cumulus Weather Fundamentals

13. Low Cloud Type - Towering Cumulus Weather Fundamentals

14. Mature Thunderstorm Weather Fundamentals

15. Mature Thunderstorm Possibilities Dry Microburst / Tornado Weather Fundamentals

16. Microburst Threat Weather Fundamentals

18. Mt Shasta Mt Fuji Mt Rainier Teton Range Lenticular Clouds Weather Fundamentals

19. Lenticular Clouds - Mountain Waves Weather Fundamentals Danger? Vertical rises of over 15 Ft/sec with Mountain Waves

20. Cloud Type – Altocumulus Weather Fundamentals

21. Cloud Type - High Clouds Weather Fundamentals

22. Clouds can indicate the type of approaching front X

23. Cold air is approaching and clouds are very close to front Cold Front X Observer Weather Fundamentals

24. Atmospheric Inversion

25. Fog Horizontal Motion (Advection) –Moist air passes over a cool surface –Well known area is in the San Francisco Bay Radiational Cooling –Moist air mass cools near the ground to the point of condensation causing fog to form –Generally you need calm winds and clear skies Weather Fundamentals

26. How weather Fronts are Defined

27. Weather Fundamentals

28. Local Hazards   Dense Fog (especially Nov – Mar)  Low Clouds and/or Visibility  Mountain Obscurations In the Winter months… In the Summer months…   Thunderstorms, with hail and/or high winds

29. Local Hazards Ice & Snow

30. Local Hazards Strong Winds

31. Local Hazards Mountain Obscurations

32. Thunderstorms and Lightning Local Hazards

33. Low Level Wind Shear Danger? Stalls and abrupt landings  Vertical Wind Shear 10 knots or more per 100 feet in a layer at least 200 feet thick  Must be within 2000 feet of Ground  PIREP reporting non-convective wind shear causing an airspeed loss/gain of 20 knots (within 2000 feet of ground) What Is It?  West winds at Sun Valley in gap to West of Tower Likely with…

34. Terminal Aerodrome Forecast  A detailed weather forecast for the next 24 hours  Valid for a 5 mile radius from the center of any airport  Elements include Visibility, Cloud Heights, Winds, and Weather  Issued daily at 00Z, 06Z, 12Z, and 18Z  May include Low Level Wind Shear What is a TAF? Example: KSUN 131741Z 1318/1418 10013KT P6SM OVC060 FM140100 10012KT P6SM SCT040 OVC070 TEMPO 1402/1406 -RA FM140600 17014KT P6SM -RA BKN040 OVC070 FM141200 21005KT P6SM SCT025 BKN045=

35. Current METAR for KPIH reported at: Apr 7 2010, 8:53 am MDT KPIH: 071453Z 22009KT 10SM CLR 02/M04 A3037 RMK AO2 SLP300 T00171039 53009 TAF: KPIH 071120Z 0712/0812 22007KT P6SM SKC FM071800 24012G18KT P6SM SCT200 FM080200 VRB05KT P6SM SCT200 Metar Observation

36. Pilot Reports  Forecasters!  Fellow Pilots!  Anyone with a flying interest  PIREPs often are the first sign of trouble, or weather to affect routes/airport terminals  REMEMBER, your PIREP is extremely valuable. Who Needs Them? Example: GEG UA /OV GEG 180008 /TM 2246 /FL 150 /TP PAY2 /SK OVC-TOP012/OVC160 /TA M07 /WV 23040KT /TB LGT OCNL MOD

37. AIRMET TANGO UPDT 2 FOR TURB VALID UNTIL 082100 AIRMET TURB...NV OR CA AND CSTL WTRS FROM 50NW LKV TO BAM TO 30W LAS TO 20E MZB TO 220SW MZB TO 140WSW FOT TO 150NW FOT TO 50NW LKV MOD TURB BTN FL230 AND FL410. CONDS CONTG BYD 21Z THRU 03Z. OTLK VALID 2100-0300Z AREA 1...TURB NV CA AND CSTL WTRS BOUNDED BY 20ENE BAM-20E OAL-40NW RZS-150WSW RZS-140SW PYE-SNS- 20ENE BAM MOD TURB BLW 140. CONDS CONTG THRU 03Z. AREA 2...TURB NV UT AZ OR CA BOUNDED BY 50NW LKV-20NNW REO-20ESE ILC-80WSW TUS-BZA-20ESE MZB- 30W LAS-BAM-50NW LKV MOD TURB BTN FL230 AND FL410. CONDS CONTG THRU 03Z. AIRMETs  Areas of Moderate Turbulence  Areas of Moderate Icing and freezing levels  Areas of IFR Conditions and mountain obscurations  Strong Convective Areas  Volcanic Ash Tracks  Issued at 13Z, 19Z, 01Z, & 07Z -- Updated as needed Issued by National Aviation Center in KCMO

38. SIGMETs  Thunderstorms greater than (33 dBZ) affecting 40% or more of a 3000 square mile area  Line(s) of Thunderstorms  Isolated Severe Thunderstorms (3/4” hail and/or 50 knot winds)  Tornadoes  Embedded Thunderstorms  Volcanic Ash  Issued when needed WSUS31 KKCI 081955 SIGE CONVECTIVE SIGMET...NONE OUTLOOK VALID 082155-090155 TS ARE NOT EXPD. Issued by National Aviation Center in KCMO

39. Upper Air Winds

40. Where to get Weather Information Information Sources - Pilot Weather Briefings @ 1-800-WEATHER - Internet -- ADDS – Aviation Weather -- DUATS -- Salt Lake City Center Weather Service Unit -- Weather Forecast Office, Pocatello -- AIM -- AOPA

41. Where to get Weather Information adds.aviationweather.gov

42. Where to get Weather information www.wrh.noaa.gov/zlc

43. www.weather.gov/pocatello Forecasts Activity Planner Southeast Idaho Discussion Aviation Fire Weather Hydrology Avalanche Recreation Graphical Outlooks Where to get Weather information

44. Weather and Accidents Source: NTSB chairman, Jim Hall’s testimony before the Committee on Transportation and Subcommittee on Aviation (22 July 1999) National Transportation Safety Board Statistics…  33% of all FATAL accidents are weather related  Of these, 40% occur within the TAF area of the airport  Low Ceilings and/or Visibilities  Icing  Thunderstorms, Lightning and/or Hail  Low Level Wind Shear Main Weather with these Crashes…

45. Weather Forecast Office Pocatello Questions? Thank You.