Aviation Weather Center:Aviation Weather Center: Products & Services OverviewProducts & Services Overview

Utility of Ensemble Model GuidanceUtility of Ensemble Model Guidance

Andy Fischer, Pat Murphy, & David BrightAndy Fischer, Pat Murphy, & David BrightChicago Aviation Weather WorkshopChicago Aviation Weather Workshop

February 25, 2011February 25, 2011

Support for the FAASupport for the FAA

System Ops Flight Standards Flight Safety

FAA – FAA – Gives NWS requirements for products/servicesGives NWS requirements for products/services

CCFP

No cost

to FAA

CWSUADDS

SIGMET

AIRMET

Area Forecast

Sig Wx Low

Winds Aloft

TAF

“Red Book” Gx

No cost to FAA

WAFS SIGWX

Intl. SIGMETs

IFFDP

No cost to FAA

ICAO/WMO

AWC’s Area of Responsibility for AWC’s Area of Responsibility for Aviation Warnings (SIGMETs)Aviation Warnings (SIGMETs)

SIGMET, AIRMET & SIGMET, AIRMET & Area ForecastArea Forecast

3 Forecast Desks 24/73 Forecast Desks 24/7 CONUS & Coastal WtrsCONUS & Coastal Wtrs

Graphic & Text ForecastsGraphic & Text Forecasts AIRMETs AIRMETs

26280 routine issues/yr26280 routine issues/yr FA FA

6570 routine issues/yr6570 routine issues/yr SIGMET (non Convective)SIGMET (non Convective)

~ 500 avg. annual~ 500 avg. annual Low-Level GraphicLow-Level Graphic

1456 routine issues/yr1456 routine issues/yr

BOSZ WA 071545 AIRMET ZULU UPDT 3 FOR ICE AND FRZLVL VALID UNTIL 072100 AIRMET ICE...ME NH VT MA AND CSTL WTRS FROM 70NW PQI YOW TO YSC TO 70NW PQI MOD ICE BTN FRZLVL AND 140. FRZLVL SFC-040. CONDS CONTG BYD 21Z THRU 03Z.

1 Forecast Desk 24/71 Forecast Desk 24/7 SIGMET for thunderstormsSIGMET for thunderstorms

““Warning” ProductWarning” Product Associated Hazards:Associated Hazards:

Turbulence, Icing, & Wind Turbulence, Icing, & Wind Shear Shear

CONUS and coastal watersCONUS and coastal waters Issued Hourly / Valid for 2 hrsIssued Hourly / Valid for 2 hrs ~ 30,000~ 30,000 issued annually issued annually

Convective SIGMETConvective SIGMET

MKCE WST 071855 CONVECTIVE SIGMET 8E VALID UNTIL 2055Z FL AND CSTL WTRS FROM 40NNE CTY-30N OMN-70WSW PIE-170W PIE-40NNE CTY AREA EMBD TS MOV FROM 27020KT. TOPS TO FL350. REF INTL SIGMET CHARLIE SERIES.

OUTLOOK VALID 072055-080055 FROM 30N CRG-190ENE OMN-100SW SRQ-100WSW PIE-30N CRG WST ISSUANCES POSS. REFER TO MOST

Collaborative Convective Collaborative Convective Forecast Product (CCFP)Forecast Product (CCFP)

1 Forecast Desk 20/71 Forecast Desk 20/7Strategic traffic flow Strategic traffic flow

managementmanagementCollaborators:Collaborators:

FAAFAAMeteorologists at Meteorologists at

CWSUs, Airlines, and CWSUs, Airlines, and AWCAWC

CanadaCanada~ 25,000 ~ 25,000 Forecast Forecast

Polygons annuallyPolygons annually

Significant Weather FcstsSignificant Weather Fcsts 2 Forecast Desk 20/72 Forecast Desk 20/7

Covers FL250 - FL630Covers FL250 - FL630 Global forecastGlobal forecast

24 hour forecast:24 hour forecast: Jet StreamsJet Streams ThunderstormsThunderstorms TurbulenceTurbulence Tropopause Tropopause

HeightsHeights Active VolcanoesActive Volcanoes Tropical CyclonesTropical Cyclones

18,980 routine 18,980 routine issuances/yr issuances/yr

Gulf of Mexico & CaribbeanGulf of Mexico & Caribbean 1 Forecast Desk 24/71 Forecast Desk 24/7 Oceanic (Atlantic and Oceanic (Atlantic and

Pacific) SIGMETsPacific) SIGMETs Weather Forecasts Weather Forecasts

primarily for Helicopter primarily for Helicopter OperationsOperations CloudsClouds VisibilityVisibility ThunderstormsThunderstorms Rain/FogRain/Fog WindWind

4,000 Operating Oil Platforms4,000 Operating Oil Platforms 30,000 personnel living on oil 30,000 personnel living on oil

platformsplatforms 600 Helicopters600 Helicopters 1.3 Million flights annually1.3 Million flights annually

World Area Forecast CenterWorld Area Forecast Center

World Area Forecast System (WAFS)World Area Forecast System (WAFS) Formulated by International Civil Aviation Organization and the Formulated by International Civil Aviation Organization and the

WMO WMO Improve the quality and consistency of enroute guidance provided Improve the quality and consistency of enroute guidance provided

for international aircraft operationsfor international aircraft operations World Area Forecast Centers (WAFC)World Area Forecast Centers (WAFC)

WAFC – WashingtonWAFC – WashingtonAWC provides Significant Weather Forecasts AWC provides Significant Weather Forecasts NCEP Central Operations Provides Wind and Temperature Grids NCEP Central Operations Provides Wind and Temperature Grids

ChartsChartsNWS Telecommunications Gateway supports satellite data broadcastsNWS Telecommunications Gateway supports satellite data broadcasts

WAFC – LondonWAFC – LondonMet Office – ExeterMet Office – Exeter

AWC Product IssuancesAWC Product Issuances

ProductProduct #/Year#/Year

Convective SIGMETConvective SIGMET ~30,000~30,000

Non-Convective SIGMETNon-Convective SIGMET 500500

Collaborative Convective Collaborative Convective Forecast Product (CCFP)Forecast Product (CCFP)

25,00025,000

AIRMETsAIRMETs 26,28026,280

Area Forecasts (FA)Area Forecasts (FA) 6,5706,570

Significant Weather LowSignificant Weather Low 1,4561,456

Significant Weather HighSignificant Weather High 18,89018,890

Operational Automated Operational Automated ProductsProducts

Graphical Turbulence Guidance (GTG)

Forecast Icing Severity (FIS)

Current Icing Product (CIP)

Forecast Icing Probability (FIP)

12

Aviation Digital Data Service (ADDS) makes available to the Aviation Digital Data Service (ADDS) makes available to the aviation community text, digital and graphical forecasts, analyses, aviation community text, digital and graphical forecasts, analyses, and observations of aviation-related weather information and observations of aviation-related weather information

Meets FAA requirements for “Qualified Internet Meets FAA requirements for “Qualified Internet Communications Provider”Communications Provider” Allows operational use by part 121/135 operators (airlines)Allows operational use by part 121/135 operators (airlines)

Operational Since 2003Operational Since 2003 AveragingAveraging

9 million hits per month9 million hits per month 100 GB per day100 GB per day

Not just a web display Not just a web display Is a dynamic databaseIs a dynamic database

Already has many NEXTGEN Already has many NEXTGEN data service capabilitiesdata service capabilities

ADDS joint developedADDS joint developed NCAR, GSD, and AWCNCAR, GSD, and AWC

New Products – Looking New Products – Looking Toward NextGenToward NextGen

Valid 18-00Z Valid 18-00Z tomorrowtomorrow

Depicts 40, 60, 80% Depicts 40, 60, 80% probability of probability of thunderthunder

Uses CCFP “look Uses CCFP “look and feel” and feel”

Quick look at where tomorrow’s Quick look at where tomorrow’s main impact will bemain impact will be

Extended Convective Forecast Extended Convective Forecast Product (ECFP)Product (ECFP)

ECFP + SPC + AWC = ECFP + SPC + AWC = ConsistencyConsistency

Automated based on SREF Prob 26hr in advance

Partially automated based on SREF 9hr in advance

6hr CCFP

Aviation Impact Guidance for Aviation Impact Guidance for Convective Weather (AIGCW)Convective Weather (AIGCW)

Historic Traffic

All levels FL > 250 FL < 100

Raw SREF Prob

Ensemble Guidance at AWCEnsemble Guidance at AWC Develop specialized guidance for the specific application

(convection and other aviation weather hazards)

Design guidance that…Help blend deterministic and ensemble approachesProvide guidance for uncertainty/probabilistic forecastsProvide guidance that aids confidence (i.e., better

deterministic forecasts) Illustrates plausible scenariosAllows for diagnostic analysis – not just a statistical black-box

NWS/NCEP Short Range Ensemble Forecast (SREF)

EMC SREF system (21 members)87 hr forecasts four times daily (03, 09, 15, 21 UTC) North American domainModel grid lengths 32-45 km Multi-model: Eta, RSM, WRF-NMM, WRF-ARWMulti-analysis: NAM, GFS initial and boundary conds. IC perturbations and physics diversityRecently added bias-correction to some fields

Ensembles Available at AWC: SREF

SREF 3h Calibrated Probability of a Thunderstorm

Thunderstorm = > 1 CG Lightning Strike in 40 km grid box

(Bright et al., 2005) http://ams.confex.com/ams/pdfpapers/84173.pdf

Perfect Forecast

No Skill

Calibrated SREF Thunder ReliabilityCalibrated SREF Thunder Reliability

Calibrated Thunder Probability

Climatology

Frequency[0%, 5%, …]

SREF Probability Convective Cloud Top > 37 KFt

Test Version: 03Z SREF Day 1 ENH Guidance (Summer 2008)

Probability Echo Tops >= 35KFT

Outline

Introduction

Short Range Ensemble Forecasts (SREF)

Future Aviation Ensemble ApplicationsApplications and calibration under development

One hourly SREF thunderstorm guidance (through F036) *Calibration of potential impacts of convection in SREF ^Rapid Refresh Ensemble Forecast (RREF) – 1hr updates, RUC based

*Storm scale (e.g., supercells, squall lines) applications being evaluated

*Not discussed today^Collaborating with John Huhn, Mitre Corp.

Gridded Flight Composite (20 km)December 2007 to August 2008 – Above 250 KFT

20 km Grid (AWIPS 215)Data from John Huhn, Mitre

Probability (%) aircraft is inside grid box

Gridded Flight Composites (20 km Grid) at 00 UTCJanuary 1, 2004 to December 31, 2008

All Flights < 10,000 Feet All Flights > 25,000 Feet

Snapshot probability of an aircraft inside the 20 km (AWIPS 215) grid box

SREF Guidance 15 UTC 10 June 2008 F009 valid at 00 UTC 11 June 2008

Calibrated Probability of a T-Storm Probability of Tops > 37,000 Feet

SREF Impact Guidance 15 UTC 10 June 2008 F009 valid at 00 UTC 11 June 2008

Impact of Thunderstorms: < 10 kft Impact of Tops: En Route > 25 kft

Future Applications: Storm Scale Ensemble (SSEF)

NOAA Hazardous Weather Testbed (HWT) HWT Spring Experiment

Focused on experimental high-res WRF forecasts since 2004 (dx ~2-4 km) Convection allowing ensemble forecasts (2007-2009) to address uncertainty

10 WRF members 4 km grid length over 3/4 CONUS Major contributions from: SPC, NSSL, OU/CAPS, EMC, NCAR Resolving convection explicitly in the model

Evaluate the ability of convection allowing ensembles to predict: Convective mode (i.e., type of severe wx) Magnitude of severe type (e.g., peak wind) Aviation impacts (e.g., convective lines/tops) QPF/Excessive precipitation Year 1 Objective (2007): Assess the role of physics vs. initial condition uncertainty at high resolution

2003 Spring Experiment

Probability Updraft Helicity > 50 m2/s2

Probability of Supercell Thunderstorms

F026: Valid 02 UTC 22 Apr 2008UH > 50 + 25 mi

Observed Radar

Radar BREF 0142 UTC 22 Apr 2008

Probability Updraft Helicity > 50 m2/s2

View of the left split looking south from Norman, OK (0145 UTC 22 Apr 2008)(Numerous large hail reports up to 2.25”)

Jack Hales

Convective Mode: Linear DetectionDetermine contiguous areas exceeding 35 dbZEstimate mean length-to-width ratio of the

contiguous area; search for ratios > 5:1Flag grid point if the length exceeds:

200 miles

Probability Linear Mode Exceeding 200 miles

Squall Line Detection F024: Valid 00 UTC 18 Apr 2008Linear mode + 25 miles

Probability Linear Mode Exceeding 200 miles

Squall Line Detection F026: Valid 02 UTC 18 Apr 2008Linear mode + 25 miles

Squall Line Detection

Probability Linear Mode Exceeding 200 miles

F028: Valid 04 UTC 18 Apr 2008Linear mode + 25 miles

Linear Convective Mode: Impacts

Aviation impacts ~ 01 UTC18 April 2008

Image provided by Jon Racy