WWRP/WGNE Joint Working Group on Forecast Verification Research

Beth Ebert, JWGFVR co-chair

WGNR meeting, Geneva, 8-10 Feb 2011

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Aims

• Verification component of WWRP

• Develop and promote new verification methods

• Training on verification methodologies

• Ensure forecast verification is relevant to users

• Encourage sharing of observational data

• Promote importance of verification as a vital part of experiments

• Promote collaboration among verification scientists, model developers and forecast providers

• Collaborate with WGNE, WCRP, CBS

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Working group members

Beth Ebert (BOM, Australia)Laurie Wilson (CMC, Canada)• Barb Brown (NCAR, USA)• Barbara Casati (Ouranos, Canada)• Caio Coelho (CPTEC, Brazil)• Anna Ghelli (ECMWF, UK)• Martin Göber (DWD, Germany)• Simon Mason (IRI, USA)• Marion Mittermaier (Met Office, UK)• Pertti Nurmi (FMI, Finland)• Joel Stein (Météo-France)• Yuejian Zhu (NCEP, USA)

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Sydney 2000 FDP

-0.1

-0.05

0

0.05

0.1

0.15

0.2

0.25

0.3

0 10 20 30 40 50 60

Forecast (min)

Ski

ll MA

E

Bia

s (m

m)

sprog

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Sydney 2000 FDP

TITAN EXTRAP

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Sydney 2000 FDP

MAEBias

Boundary position error

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Beijing 2008 FDP

Real Time Forecast Verification (RTFV) system

Fast qualitative and quantitative feedback on forecast system performance in real time

– Verification products generated whenever new observations arrive

Ability to inter-compare forecast systems

3 levels of complexity– Visual (quick look)

– Statistics (quantitative)

– Diagnostic (more information)

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Training

In person Online

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Domain and variables

Outer Beijing

Beijing

Urban Beijing

Reflectivity, cell tracks,T-storm strike probability

Precipitation, probability of precipitation

Wind gusts, lightning

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Precipitation accumulation

Observations

Forecasts

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Standard verification

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Diagnostic verification (non-real time)

Power spectral density

Contiguous rain area (CRA)

Intensity-scale

Neighborhood methods

Forecast quality metric (FQM)

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Survey of BMB forecasters and FDP experts

• Real time verification considered very useful• Forecasters preferred scatter plots and quantile-quantile

plots• Experts wanted capability to drill down to more specific

information• Web interface not user-friendly enough

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B08FDP lessons for real time verification

• Format and standardization of nowcasts products was critical to making a robust verification system

• Difficult to compare "like" products that were produced with slightly different aims (e.g., QPF for warning vs hydrological applications)

• Verification system design could be improved

– Better display of forecasts with observations

– User control of verification parameters for exploring results

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SNOW-V10

• Verification plan

– User-oriented verification for Olympic period of all forecasts, tuned to decision points of VANOC

– Verification of parallel model forecasts for Jan to August 2010

– Nowcast and regional model verification

• Rich dataset for user-oriented verification and research

• Processing started

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SNOW-V10 observations

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Variable Cat 1 Cat 2 Cat 3 Cat 4 Cat 5 Cat 6 Cat 7 Cat 8 Cat 9

Temperature (°C)

-25 < -25≤ T<-20 -20≤ T<-4C -4≤ T<-2 -2≤ T< 0 0≤ T< +2 +2 ≤ T< +4 ≥ +4

RH (%) < 30% 30≤ RH<

65% 65≤ RH<

90% 90≤ RH<

94% 94≤ RH<

98%≥ 98%

Winds (m/s) < 3 3 ≤ w < 4 4 ≤ w < 5 5 ≤ w < 7 7 ≤ w < 11 11 ≤ w < 13 13 ≤ w < 15 15 ≤ w < 17 ≥ 17

Wind Gust (m/s)

< 3 3 ≤ w < 4 4 ≤ w < 5 5 ≤ w < 7 7 ≤ w < 11 11 ≤ w < 13 13 ≤ w < 15 15 ≤ w < 17 ≥ 17

Wind Direction

d ≥ 339 & d < 24º (N)

24 ≤ d < 69º (NE)

69 ≤ d < 114º (E)

114 ≤ d < 159º (SE)

159 ≤ d < 204º (S)

204 ≤ d < 249º (SW)

249 ≤ d < 294º (W)

294 ≤ d < 339º (NW)

Visibility (m) v < 30 30 ≤ v < 50 50 ≤ v < 200200 ≤ v <

300300 ≤ v <

500≥ 500 - -

Ceiling (m) c < 50 50 ≤ c< 120 120 ≤ c< 300 300 ≤ c< 750 750 ≤ c<

3000 c ≥ 3000 - - -

Precip Rate (mm/hr)

r = 0 (None)0 < r ≤ 0.2

(Trace)0.2 < r ≤ 2.5

(Light) 2.5 < r ≤ 7.5 (Moderate)

r > 7.5 (Heavy)

- - - -

Precip Type No Precip Liquid Freezing FrozenMixed

(w/Liquid)Unknown - - -

Table 5 (2nd Revised Suggestion for SNOW-V10 Verification)

Suggested categories for SNOW-V10 analysis

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Forecast < 30 30 ≤ x < 50 50 ≤ x < 200 200 ≤ x < 300 300 ≤ x < 500 > 500 Total< 30 0 0 0 0 0 2 2

30 ≤ x < 50 0 0 1 0 1 3 550 ≤ x < 200 0 0 36 10 12 53 111

200 ≤ x < 300 0 0 15 11 9 32 67300 ≤ x < 500 0 0 5 0 10 35 50

> 500 0 10 928 278 191 3824 5231Total 0 10 985 299 223 3949 5466

lam1k Min. Visibility (m) [FB param.] at VOL HSS=0.046Observed

Forecast < 30 30 ≤ x < 50 50 ≤ x < 200 200 ≤ x < 300 300 ≤ x < 500 > 500 Total< 30 0 0 0 0 0 0 0

30 ≤ x < 50 0 0 0 0 0 0 050 ≤ x < 200 0 0 52 20 22 43 137

200 ≤ x < 300 0 0 76 18 19 103 216300 ≤ x < 500 0 1 26 15 12 60 114

> 500 0 9 831 246 170 3743 4999Total 0 10 985 299 223 3949 5466

lam1k Min. Visibility (m) at VOL HSS=0.095Observed

Visibility verification

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Forecast 339° ≤ x < 24° 24° ≤ x < 69° 69° ≤ x < 114° 114° ≤ x < 159° 159° ≤ x < 204° 204° ≤ x < 249° 249° ≤ x < 294° 294° ≤ x < 339° Total339° ≤ x < 24° 15 9 21 4 1 6 10 15 81

24° ≤ x < 69° 39 66 178 40 15 24 30 30 42269° ≤ x < 114° 96 250 1155 205 48 56 45 71 1926

114° ≤ x < 159° 21 34 249 255 68 25 11 10 673159° ≤ x < 204° 7 14 121 166 144 20 11 4 487204° ≤ x < 249° 5 11 53 53 58 73 56 10 319249° ≤ x < 294° 52 26 102 29 18 74 232 162 695294° ≤ x < 339° 89 45 78 40 13 38 188 454 945Total 324 455 1957 792 365 316 583 756 5548

lam1k Wind Direction at YVR HSS=0.296Observed

Forecast < 3 3 ≤ x < 4 4 ≤ x < 5 5 ≤ x < 7 7 ≤ x < 11 11 ≤ x < 13 13 ≤ x < 15 15 ≤ x < 17 > 17 Total< 3 1498 407 201 226 28 0 0 0 0 2360

3 ≤ x < 4 382 278 200 234 48 1 0 0 0 11434 ≤ x < 5 202 205 203 288 82 4 0 0 0 9845 ≤ x < 7 69 74 91 328 269 7 1 0 0 839

7 ≤ x < 11 6 2 8 58 90 16 28 9 5 22211 ≤ x < 13 0 0 0 0 0 0 0 0 0 013 ≤ x < 15 0 0 0 0 0 0 0 0 0 015 ≤ x < 17 0 0 0 0 0 0 0 0 0 0

> 17 0 0 0 0 0 0 0 0 0 0Total 2157 966 703 1134 517 28 29 9 5 5548

lam1k Wind Speed (mps) at YVR HSS=0.234Observed

Wind verification

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Sochi 2014

Standard verification

Possible verification innovations:• Road weather forecasts

• Real-time verification

• Timing of events – onset, duration, cessation

• Verification in the presence of observation uncertainty

• Neighborhood verification of high-resolution NWP, including in time-height plane

• Spatial verification of ensembles

• User-oriented probability forecast verification

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PublicationsPublications

Recommendations for verifying deterministic and probabilistic quantitative precipitation forecasts

Available on WWRP web site

Coming soon:

Recommendations for verifying cloud forecasts

Later this year (?):

Recommendations for verifying tropical cyclone forecasts

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Publications

January 2008 special issue of Meteorological Applications on forecast verification

–Verification review paper authored by JWGFVR members

–18 contributed papers from participants in 2007 International Verification Methods workshop

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Publications

DVD from 2009 Helsinki Verification Tutorial

Video and powerpoint lectures– Verification basics– Continuous verification – Categorical verification– Warnings verification– Probabilistic verification – Spatial verification– Statistical inference

Available from WMO

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Spatial Verification Method Intercomparison Project

• International comparison of many new spatial verification methods

• Methods applied by researchers to same datasets (precipitation; perturbed cases; idealized cases)

• Subjective forecast evaluations

• Workshops: 2007, 2008, 2009

• Weather and Forecasting special collection

• 13 papers on specific methods, 2 overview papers

http://www.rap.ucar.edu/projects/icp

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Spatial Verification Method Intercomparison Project

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Facial verification?

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Spatial Verification Method Intercomparison Project

• Future variables – "Messy" precipitation– Wind– Cloud– Timing errors

• Future datasets– MAP D-PHASE– SRNWP / European data– Nowcast dataset(s)??

• A model for verification test bed

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Outreach

• Strong focus of the WG

• EUMETCAL training modules completed (Nurmi, Wilson)

• Verification web page

• Sharing of tools

• Tutorials (traveling and on-site)– ECMWF (Jan 2007)– South Africa (Sept 08)– Helsinki (June 2009)

http://www.cawcr.gov.au/projects/verification/

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International Verification Methods Workshops 4th Workshop – Helsinki 2009

Tutorial

• 26 students from 24 countries

• 3 days

• Lectures, hands-on (took tools home)

• Group projects - presented at workshop

Workshop

• ~100 participants

• Topics: – User-oriented verification

– Verification tools & systems

– Coping with obs uncertainty

– Weather warning verification

– Spatial & scale-sensitive methods

– Ensembles

– Evaluation of seasonal and climate predictions

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Workshop: New verification research

Spatial methods applied to:

http://www.space.fmi.fi/Verification2009/

Wind fields Ensemble forecasts

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Workshop: New verification research

http://www.space.fmi.fi/Verification2009/

ExtremesDiagnostics

False alarm ratio

Hit

rate

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5th International Verification Methods Workshop

• Melbourne, December 2011

• 3-day tutorial + 3-day scientific workshop

• Additional tutorial foci

– Verifying seasonal predictions

– Brief intro to operational verification systems

• Capacity building for FDPs/RDPs, SWFDP, etc.

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New focus areas for JWGFVR research

• Seamless verification – crossing space/time scales

• Ensemble predictions

• Warnings / extreme events, especially timing

• Aviation

• Multivariate verification – joint distributions

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Future collaboration with WGNR

• SNOW-V10

• Sochi 2014

• WENS?

• SWFDP (Africa, SW Pacific, SE Asia)

• Lake Victoria FDP

Intend to establish collaborations with SERA on(a) verification of tropical cyclone forecasts and other

high impact weather warnings(b) Lake Victoria FDP