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NCEP Update: Focus on Winter. Louis W. Uccellini Director, NCEP Northeast Regional Operational Workshop Albany, New York November 1, 2005. “Where America’s Climate, Weather and Ocean Services Begin”. Outline. NWS “Seamless Suite” Some recent advancements Seasonal Medium Range
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NCEP Update: Focus on Winter Louis W. Uccellini Director, NCEP Northeast Regional Operational Workshop Albany, New York November 1, 2005 “Where America’s Climate, Weather and Ocean Services Begin”
Outline • NWS “Seamless Suite” • Some recent advancements • Seasonal • Medium Range • Day 4-7 NDFD • Day 1-3 Winter Weather Desk • SREF Support • Other update items • Space Environment Center • Computer • WRF • Building
CFS 2x/day Week 2 Hazards Assessment CDC 6-10 Day Forecast Upgrade HPC-NDFD, Days 4 -7 NAEFS HPC Winter Weather Desk Days 1-3 WRF/SREF
The NCEP coupled Climate Forecast System (implemented August 24, 2004) • Global Forecast System 2003 (GFS03) • T62 in horizontal; 64 layers in vertical Atmospheric component Oceanic component • GFDL MOM3 (Pacanowski and Griffies, 1998) • Once per day coupling • Sea ice extent based on observed climatology Model now run twice per day • 60 runs per month used for a 9 month ensemble prediction
CFS Seasonal Precip Forecast (mm/month) Without skill mask
CFS Seasonal Precip Forecast (mm/month) With skill mask • If anomaly correlation between forecast and observed conditions over the 1982-2003 period is below 0.3, values are not shown
CFS Seasonal Temp Forecast (deg/month) Without skill mask
CFS Seasonal Temp Forecast (deg/month) With skill mask • If anomaly correlation between forecast and observed conditions over the 1982-2003 period is below 0.3, values are not shown
CPC Winter Season Forecast 2005-06
North American Ensemble Forecast System International project to produce operational multi-center ensemble products • Combines global ensemble forecasts from Canada & USA • Now: CAN – 16/day out to 10 days, US – 40/day out to 16 days • ’06 – CAN 40/day out to 16 days, US – 56/day out to 16 days • ’07 – CAN 40/day out to 16 days, US – 80/day out to 16 days • Generates products for • Intermediate users: weather forecasters at NCEP Service Centers and WFOs • Specialized users: hydrologic applications in all three countries • End users: forecasts for public distribution in US, Canada (MSC) and Mexico (NMSM) • Future activities • Adding products (probabilistic in nature) • Incorporating ensemble data from other centers (e.g., FNMOC) • Unified evaluation/verification procedures
NAEFS Products • NAEFS basic product list • 11 functionalities • Ensemble mean, spread, probabilities, etc • 50 variables • U,v,t,z,CAPE, precip type, etc. • 7 domains • Global, NH, NA, CONUS, SA Carib., Africa • 300-400 products requested by users (will be supplied via priority order) • Graphics • NAWIPS (March 06) • NCEP Model Web Page – as early as March 2006 on experimental basis • Grids • NAWIPS • ftp site (GRIB2) in planning phase (Mar 06) • NDGD in planning phase (Mar 06) • Still working availability issues - first priority: “intermediate” users
ENSEMBLE 10-, 50- (MEDIAN) & 90-PERCENTILE FORECAST VALUES (BLACK CONTOURS) AND CORRESPONDING CLIMATE PERCENTILES (SHADES OF COLOR) 10 percentile 50 percentile 90 percentile
8-14 day Outlook 6-10 day Outlook Outlooks for period of rainfall from remnants of Tropical Storm Tammy Hazards Assessment
8-14 day forecast valid Oct 29 – Nov 4, 2005 6-10 day forecast valid Oct 30 – Nov 3, 2005 Precipitation Temperature Temperature Precipitation
4-7 Day HPC Gridded Forecast • Maximum temperature • Minimum temperature • 12 hour PoP • 6 hourly dew point • 6 hourly wind (direction and speed) • 6 hourly cloud cover • 12 hourly weather • The following grids are being generated daily • Experimental grids can be viewed here • http://www.hpc.ncep.noaa.gov/5km_grids/5km_gridsbody.html • Production Methodology documentation • http://www.hpc.ncep.noaa.gov/5km_grids/medr_5km_methodology.pdf • All grids extend offshore to cover the coastal waters • Verification program underway
HPC/NDFD Highlights • For decades HPC provided day 3 - 7 guidance • Max Temp, Min Temp, 24 hr (later 12 hr) Pop, surface progs • Spring 2004 - HPC asked to provide forecasts for additional fields including dew point, sky cover, wind direction and speed, and precipitation type • HPC requested to deliver these forecasts as 5 km grids • HPC began providing these fields in June 2004.
Methodology • HPC has 2 forecasters/shift preparing day 4 – 7 forecasts (one shift/day) • One prepares surface progs and writes the narrative • Second prepares the max/min temperatures and PoPs • HPC uses N-AWIPS to generate forecasts • Forecasters start with MOS max/min temps and MOS12 hr PoPs • Forecasters can edit 384 stations; usually edit ~ 20 - 25% of stations for a particular forecast • Usually focus on areas they expect MOS to be deficient due to synoptic scale considerations • Additional fields increased the number of grids from 16 to 102 • No additional forecasters made available • Only solution was to generate additional fields automatically • Basic philosophy is to generate a set of grids consistent with the manually generated forecasts (H, L, Fronts) • Each additional field is generated from a manually prepared HPC product • Currently, these additional fields are not touched by a forecaster
Grid Production • Max/min temperature grids are produced by interpolation of manually prepared point forecasts to a grid with Prism climatology as a background • PoP grids are interpolated from HPC modified stations • Dew points use the HPC temperature forecasts and MOS ensemble with Prism climatology as a background • Cloud cover is based on HPC PoPs and max temps • Winds are based on HPC surface progs • Precipitation type is based on HPC max/min temperature forecasts and on PoPs (for aerial coverage) • WFOs provide input between “preliminary” and “final” product release through 12Planet
Verification Results • In general, HPC point forecasts are as good as or better than MOS and NDFD • HPC winds are poorest of all HPC grids • These results have been consistent from month to month
How HPC adds value to Day 4 - 7 • HPC shows 5 – 10% improvement over MOS • Is this a good use of resources?
How HPC adds Value to Day 4 – 7 (Cont.) HPC BIG WIN VS BIG LOSS PERCENTAGES COMPARED TO GFS MOS 2004 • A “Big win” or “Big loss” occurs when HPC beats or looses to MOS by > 10 degrees. • In those cases, HPC is better than MOS ~ 80 percent of the time (sample size ~ 35 - 40) % of time
4-7 Day Gridded Products Maximum Temperature 4 day valid Nov 1 5 day valid Nov 2 6 day valid Nov 3 7 day valid Nov 4
4-7 Day Gridded Products Minimum Temperature 4 day valid Nov 1 5 day valid Nov 2 6 day valid Nov 3 7 day valid Nov 4
Issues • Time of release of forecasts • Some WFOs want HPC to issued grids earlier • HPC starts with MOS rather than previous forecast • Field prefers less “flip-flopping” • How involved do forecasters need to be? • Are post-processed grids good enough? • Should HPC provide probabilistic info? • QPF – exceedance values • Day 4 – 7 – ranges in addition to “best guess” • How is collaborative approach sustained?
Future Plans • Continued improvement of methodology • Better algorithms for post processed fields • Faster processing of grids for earlier delivery • Better hardware • Optimize processing • Expand coverage to OCONUS • Explore other ways of creating sensible weather grids • Greater use of ensembles to create grids from selected blend (NAEFS) • Forecasters focus on model selection and modification
Winter Weather NWS Winter Weather Desk • Goals of 4 year experiment from 2001- 2004: • Improve Winter Weather Services to the public through coordination of the winter weather watches/warnings with National guidance products • Test short range ensemble for their applications to winter weather forecasting • Motivation: • Jan 24-25, 2000; December 30, 2000: March 4-6, 2001 • WWD “operational” September 15, 2004
Regional Stats To date NWS FY05 LT is 18h, 3h greater than GPRA goal of 15h * Oct - Mar
February 28, 2005 Event 48 hr prob of >4” 24 hr prob of >4” 24 hr storm track 24 hr snowfall
Winter Weather Desk Status • Time line: Sep 15 – April 1 • Participants • NCEP HPC • Provide SREF based Winter Wx guidance • Collaborate with WFOs (Chat Room Technology) • WFOs • All CONUS WFOs • Use guidance from NCEP to produce coordinated Winter Storm Watches/Warnings • Products: http://www.hpc.ncep.noaa.gov/wwd/winter_wx.shtml • 24 h probability (low, moderate, high) of meeting/exceeding 4”, 8”, 12” snow, 0.25” freezing rain (for day 1, 2, 3) • 72h Low tracks graphic and discussion
Off to a good start Began operational status 00Z Sept 15 Three significant event so far: all verified exceptionally well for snowfall amount and watch/warning criteria Ern MT into the Dakotas (Oct 4-5) Collaboration conducted with FGF, BYZ, GGW, BIS, UNR Front Range Event (Oct 9-10) Collaboration conducted with CYS and PUB Northeast Event (Oct 24-25) Collaboration conducted with RLX, OKX, PHL, LWX Early challenges Staffing WWD during active tropical season ! Training HPC staff (vets and newbies) and WFOs Winter Weather Desk Status (cont.)
> 8 in > 12 in Day 2 Probability of Snow Valid 12Z Oct 10 – 12Z Oct 11
Short Range Ensemble Forecast • 15 members twice per day • 87 hrs from 9 and 21Z • Resolution 32km/60 levels • Mean and spread charts available for forecaster use • Developing products on probability of snow and ice accumulation • http://wwwt.emc.ncep.noaa.gov/mmb/SREF/SREF.html 0.01” snow
SREF Upgrades • FY2005 • Improved and new products (Convective, Aviation, Winter Weather) • Output SREF forecasts for Alaska and Hawaii • Add RSM BUFR files • Common WRF post-processor • FY2006 • Add six members twice per day (WRF ARW & WRF NMM) • Run SREF 4 times per day (03, 09, 15 and 21 UTC) • Implement Grid Based Bias Correction • Improve Probabilistic FVS verification • Develop spread information for NDGD • Add WRF BUFR Files • Implement ensemble mean BUFR files
New Impact Graphics from SREF • Probability event will last more than 12, 24, 48 hrs • Probability visibility will be reduced to 1/2, 1/4, or 1/8 mile in winter precip • Probability winter precip rate will be more than 1, 2, or 3" per hr • Probability road sensor will detect winter precip (relative to normal) • Probability Blizzard Criteria will be met • Probability Freezing Rain .01" or more will accumulate on any surface • Probability NWS Winter Storm Warning criteria will be met (under construction)
National Operational Hydrologic Remote Sensing Center Analysis Snow Depth as of 12Z Oct 26
Low tracks Valid 12z Oct 24, 2005 Thru 12Z Oct 27, 2005
>8 in >12 in 48 hour probability of snow Valid 12Z Oct 25 – 12Z Oct 26 >4 in
NCEP: Other Update Items • Space Environment Center • Computing Capability • WRF Update • Building
Space Environment Center • SEC formally joined NCEP/NWS/NOAA on January 9 • Their addition helps foster a seamless suite of operational products from the “Sun to the Sea” • Provides space weather alerts and warnings for disturbances that can affect people and equipment working in space and on Earth • Service/Science linkage offers many exciting challenges for future growth to insure the delivery of weather/ocean/climate products to a diverse and increasingly sophisticated user community (e.g., climate, aviation)
Computing Capability $26.4M/Year Investment Commissioned/Operational IBM Supercomputer in Gaithersburg, MD (June 6, 2003) • Receives Over 210 Million Global Observations Daily • Sustained Computational Speed: 1.485 Trillion Calculations/Sec • Generates More Than 5.7 Million Model Fields Each Day • Global Models (Weather, Ocean, Climate) • Regional Models (Aviation, Severe Weather, Fire Weather) • Hazards Models (Hurricane, Volcanic Ash, Dispersion) • 2.4x upgrade operational on January 25, 2005 • Backup in Fairmont, WV operational on January 25, 2005
2005 NCEP Production Suite Atmospheric Model Dependencies Forecast GENS GFDL G G S I WRF-NMM WRF-ARW ETA RSM SREF GFS Dispersion Sev Wx WRF-NMM WRF-ARW E D A S CFS NAM - Eta Air Quality NOAH Land Surface Model RUC L D A S
WRF Implementation Schedule • “HiResWindow” for Hazardous Weather: (ARW and NMM) Implemented operationally at NCEP on 6/28/05 (~5 km) • WRF SREF members: Operational FY06 (1st Qtr) • North American WRF: Operational in FY06 (3rd Qtr) • WRF SREF: Fully Operational in FY07* • Hurricane WRF: Operational in FY07* • Rapid Refresh WRF: Operational in FY07* • WRF Chem: Beyond FY08* * As resources allow
2007 NCEP Production Suite Atmospheric Model Dependencies Forecast Hurricane WRF GENS G G S I WRF-NMM WRF-ARW RSM ? SREF GFS Dispersion Sev Wx WRF-NMM WRF-ARW R G S I CFS NAM - WRF Chem WRF* Air Quality NOAH Land Surface Model Rapid Refresh WRF L D A S *FY08
NOAA Center for Weather and Climate Prediction • Defined requirements for 268,762 RSF • Includes housing 800 Federal employees, contractors, and visiting scientists • 5 NCEP Centers • NESDIS research and satellite services • OAR Air Resources Laboratory • Begin move to new facility September ’07 and complete by Feb ‘08
Summary • Making progress with collaborative forecasting • Across entire spectrum from climate to weather • Event-driven to standard day-to-day forecasts • NCEP Service and Modeling Centers are “ready for winter” • Making progress with a community modeling approach across all time scales – increasingly ensemble based • NCEP infrastructure issues being addressed • Computer • Buildings (UMD and OU (SPC))