1. Tuning an Analysis and Incremental Analysis Updating (IAU) Assimilation for an Efficient High Resolution Forecast System
Keith A. Brewster1
Derek R. Stratman1,2
1Center for Analysis and Prediction of Storms 2School of Meteorology
University of Oklahoma
IOAS-AOLS
New Orleans, LA January, 2016
Keith Brewster
Senior Research Scientist & Associate Director
Center for Analysis and Prediction of Storms
University of Oklahoma
OU-NJU Symposium May, 2015

2. Dallas-Fort Worth Urban Testbed
Population ~ 6.5 million
(4th largest city in U.S.)
Severe weather – Floods, tornadoes, hail, severe winds, droughts
Weather sensitive industries – transportation hubs (ground, air, rail), sporting venues
Network of Networks approach
Primary focus is urban flooding & severe weather

3. Observation Summary Conventional Observations
Non-Conventional Observations
ASOS
EarthNetworks (WxBug)
AWOS
CWOP
GST MoPED
Oklahoma & W Texas Mesonets
S-band WSR-88D Radars
X-band Radars
C-band TDWR Radars
Radiosondes
SODARs
Radiometers

4. Surface Observations
AWOS & ASOS
WxBUG & CWOP

5. Building the Radar Network Dual-Doppler Angle Analysis
Combined Network
NEXRAD: KFWS
TDWR: TDAL, TDFW X-Band Network: 8 Radars
Avg Beam Height: 600 m

6. 2015 Operational Configuration
OSCER Boomer
Xeon64 Oct-core SandyBridge 2.0 GHz
Analyses at 400 m Resolution Dedicated Queue
3DVAR and Cloud Analysis
Sfc, Profilers, VAD, Radar Wind and Reflectivity
5-minute Interval
400-m grid spacing Grid Size 448 x 456 x 28
Processors: 8 x 24 = 192
Obs Processing & Analysis Wallclock ~8 min
Assimilation/Forecasts On-Demand
3DVAR and ARPS with 10-min IAU
Sfc, Profilers, VAD, Radar Wind and Reflectivity Assimilation
2-hour Forward Forecast
15 minute interval
1-km grid spacing Grid Size 363 x 323 x 53
Processors: 12 x 16 = 192
Obs Processing + Analysis + Forecast Wallclock ~20-25 min

7. 400-m Analyses 26 Dec 2015
0000 UTC
0005 UTC
0010 UTC
0015 UTC

8. Recent Improvements
Updated the cloud analyses handling of reflectivity to be exactly reversible to reflectivity plotting algorithms for all microphysics options in ARPS and WRF.
Updated IAU process to better handle multi-moment microphysics.
Recently added SODAR and MoPED automated processing to realtime system.
Tuning scripts to further reduce latency.

9. Updated IAU Scheme Variable-Dependent IAU Timing
Typical Triangular Timing
Variable-Dependent Timing
Variable-Dependent Timing

10. April 24, Hail Case
Test Using Milbrant & Yau Single-Moment Microphysics

11. Variable-Dependent Timing “B”

12. Variable-Dependent Timing “C”

13. After 10 Minutes IAU Variable Anx IAU-Orig IAU-B IAU-C Snow 14.3 g/kg
4.0
5.3
10.0
Graupel
6.0
2.1
2.0
Hail
0.3
0.6 W
8.4 m/s
6.2
7.5
7.9 A B C

14. December, 2015 Operational Configuration

15. D/FW Metro Tornado Tracks, 26 Dec 2015
Blue Ridge EF-1
UTC
Farmersville EF-1
UTC
Copeville EF-2
UTC
Garland-Rowlett EF-4
UTC
Rockwall County
Ovilla
UTC
Preliminary Data NOAA Damage Survey Viewer

16. 1-km Forecast Initialized 2330 UTC 26-Dec-2015

17. Conclusions/Future Plans
Realtime Data Analyses and Forecasts Operating with Low Latency
Updated Hydrometeor Retrieval for Multiple Microphysics Schemes
Developed new IAU with Variable-Dependent Timing
New OSCER Schooner Coming Online Soon.
Faster processors 2x10 cores per chip.
Should allow update to 2-moment microphysics
Thanks to CASA Colleagues from UMass, CSU, NCTCoG, OSCER Staff
Thanks to National Mesonet Program, NOAA OS&T
CAPS Forecasts Online
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