1. Operational Use of the Rapid Update Cycle COMAP Symposium 16 December 1999 Stan Benjamin - NOAA/FSL benjamin@fsl.noaa.gov http://maps.fsl.noaa.gov - RUC/MAPS web page

2. The 1-h Version of the RUC Data cutoff - +20 min, 2nd run at +55 min at 0000, 1200 UTC

3. 3 RUC/MAPS Purpose Provide high-frequency mesoscale analyses and short-range numerical forecasts for users including: –aviation –severe weather forecasting –general public forecasting –other transportation –agriculture

4. What Runs Where Rapid Update Cycle (RUC) –Operational Version at NCEP Mesoscale Analysis and Prediction System (MAPS) –Experimental Version at NOAA/ERL/FSL (Essentially the same software. New capabilities tested first in MAPS at FSL)

5. Uses of the RUC Explicit Use of Short-Range Forecasts Monitoring Current Conditions with Hourly Analyses Evaluating Trends of Longer-Range Models Some places where the RUC is used –Aviation Weather Center - airmets, sigmets –Storm Prediction Center - severe weather watches –FAA – CWSUs, WARP, air traffic management (CTAS), ITWS.. –National Weather Service Forecast Offices –Airline Forecasting Offices –NASA Space Flight Centers –Private vendors

6. 6 NWS Forecast Discussion Use of RUC - Feb-Nov 1999 100-400 40-99 20-39 10-19

7. 7 http://maps.fsl.noaa.gov

9. Hourly Data for 40 km MAPS/RUC-2 Yellow items new for RUC-2 **not used since 1/99 in RUC or EDAS pending QC issues Data Type~NumberFreq.Use Rawinsonde (inc. special obs) 80/12hNCEP and FSL WPDN/NPN profilers 31/ 1hNCEP and FSL - 405 MHz Boundary layer profilers 15/ 1hFSL only RASS (WPDN and PBL) 15/ 1hFSL only VAD winds (WSR-88D)110-130/ 1h **NCEP & FSL Aircraft (ACARS)(V,temp) 700-3000/ 1hNCEP and FSL Surface - land (V,p sfc,T,T d )1500-1700/ 1hNCEP and FSL Buoy 100-200/ 1hNCEP and FSL

10. Hourly Data for 40 km MAPS/RUC-2 (cont). Yellow items new for RUC-2 Data Type~NumberFreq.Use GOES precipitable water1000-2500/ 1hNCEP and FSL GOES high-density cloud drift winds (IR, VIS, WV cloud top)1000-2500/ 3hNCEP and FSL SSM/I precipitable water1000-4000/2-6hNCEP only Ship reports 10s/ 3hNCEP only Reconnaissance dropwinsonde a few/ variable NCEP only Real-time observation counts at http://maps.fsl.noaa.gov for RUC-2 and 40-km MAPS

11. 11 Advantages of  Coords for Data Assimilation Analysis - adaptive 3-d correlation structures and analysis increments, esp. near  baroclinic zones - improved coherence of observations near fronts for QC Forecast Model - reduced vertical flux through coordinate surfaces, leading to reduced vertical dispersion -- much of vertical motion implicit in 2-d horiz. advection - conservation of potential vorticity - reduced spin-up problems (Johnson et al. 93 MWR)

12. RUC hybrid-b levels - cross-section Hybrid-b levels - solid  levels (every 6 K) - dashed No discontinuities at  transitions

13. 13 Effect of vertical coordinate on frontal features Turbulence diagnostic at FL200 (20,000 ft) - calculated from native grid from both MesoEta and RUC (matched forecast times) Sharper frontal resolution with RUC despite coarser horizontal resolution and fewer vertical levels

14. 14 Rapid Update Cycle – Present and Next Version 1999 Operations2000-01 Operations Resolution40 km, 40  levels20  15 km, 40  50-60  levels AnalysisOptimal interpolation on3-d variational technique on generalized on generalized  surfaces  surfaces, hydrometeor analysis w/ GOES…, use raw instead of interp. obs AssimilationIntermittent 1-h cycleIntermittent 1-h cycle Stable cloudsMixed-phase cloud microphysics MM5),Improved microphysics, / precipitation explicit fcst of cloud water, rain water, addition of drizzle snow, ice, graupel, no. concentration of ice particles Sub-grid-scaleGrell (1993)Modified Grell, scale dependence, precipitation shallow convection, interaction w/ cloud microphysics TurbulenceBurk-Thompson explicit TKE schemeRefined Burk-Thompson or e-  RadiationMM5 LW/SW scheme, f(hydrometeors)Refined MM5 scheme Land-sfc processes6-level soil/veg model (Smirnova, Add vertical soil type variability, 1997, 1999) w/ frozen soil, 2-layer snow improved cold season processes Sfc conditionsDaily 50km SST/14 km LST,Combine sat T skin, use 3-d soil type 0.14  monthly NDVI veg frac, cycled soil moisture/temp, snow depth/temp

15. RUC-2 Analysis Background (1-h fcst usually) subtracted from all obs –Analysis is of forecast error QC - buddy check, removal of VADs w/ possible bird contamination problems 3-part analysis (all using optimal interpolation) –1) univariate precipitable water (PW) analysis - using satellite PW obs - update mixing ratio field –2) z/u/v 3-d multivariate analysis update  v based on height/thickness analysis increment update p sfc from height analysis increment at sfc update u/v at all levels Partial geostrophic balance – vertically dependent, weakest at surface

16. RUC-2 Analysis, cont. - 3) univariate analyses condensation pressure at all levels  v at all levels update u/v near sfc and p sfc (univariate analysis) with smaller correlation lengths Pass through soil moisture, cloud mixing ratios, snow cover/temperature (will alter these fields in future, cloud analysis parallel cycle now running)

17. RUC-2 Analysis, cont. Vertical spreading (correlation of forecast error) based on potential temperature separation (not pressure separation as w/ other models) Analysis in generalized vertical coordinate (code applicable to pressure, sigma, or eta analysis) except for adjustment at end to reference potential temperatures and new p sfc Background is usually previous 1 hr RUC forecast

18. 18 Raob soundingRUC2 grid sounding Close fit to observations in RUC2 analysis

19. 19 RaobRUC after fixRUC before fix 7 April 99 significant-level fix in RUC-2

20. 20 Use of ‘minimum topography’ for 2m T/Td fields from RUC2 RUC2 2m T/Td fields are not valid at model terrain surface Instead, they are derived from model surface fields and lapse rates in lowest 25 mb to estimate new values using a different topography field that more closely matches actual METAR elevations “Minimum topography” – minimum 10km value inside each 40km grid box, then updated with high-resolution analysis using actual METAR elevations.

21. 21 Minimum topo for 2m T/Td Model topo RUC2 topography fields

22. RUCS 60 km Hourly Surface Analyses (same as AWIPS MSAS) Draws fairly closely to data Persistence background field (1 hr previous analysis –QC vulnerable to consistent data problems –no consistency with terrain effects except as reflected in observations MAPS sea-level pressure, (Benjamin & Miller, 1990 MWR) Blending to data-void region from NGM

23. Surface Analyses/Forecasts in RUC-2 integrated with 3-d 40 km 1 hr cycle dynamic consistency with model forecast => accounts for: –land/water, mtn circulations, sea/lake breezes, snow cover, vegetation… improved quality control - model forecast background prevents runaway bullseyes forecasts out to 12 hr in addition to hourly analyses

24. 24 RUC2 Surface Analysis Topographical features more evident with model background RUCS 60km surface analysis Little consistency with nighttime drainage Divergence - 0900 UTC 20 Jan 98 (blue - conv, green/yellow - div)

25. 25 Divergence - RUC2 Surface Analysis - 0600Z 19 April 96 Consistency with topographical features in model (land/water roughness length variations in this case)

26. Surface Analyses/Forecasts in RUC-2, cont. Same fields as in 60 km RUCS, plus all fields available in 3-d system RUC-2 sfc files (GRIB) 0.3 MB / output time all variables from RUCS plus precip precip type stability indices

27. RUC-2 use of surface data All winds, sfc pressure obs used T/Td used if abs (P station - P model ) < 70 mb - about 90% west of 105ºW, 99% east of 105ºW Eta48Eta29RUC40 FGZ 01810 TUS601344 SLC596859 MFR1094867 OAK181525 SAN12523 DRA422934 GJT9810565 RIW1042716 GEG411 1 GTF26414 UIL14911 SLE501522 BOI552124 GGW2913 5 VBG532 3 ** within 5 mb of closest fit |p model - p stn |

28. RUC surface temperature forecasts - verification against all METARs in RUC domain RMS error Bias (obs - forecast) persistence Validation time Excellent analysis fit to surface obs (also wind, Td) 3-h forecast better than 3-h persistence

29. 29 Effect of 6 May 1999 Fix to surface temperature diagnosis in RUC2 Improved lapse rates in extrapolation from RUC2 model terrain to different terrain file (“minimum topography”) used for sfc T/Td diagnosis.

30. 30

31. 31

32. 32 -3 -2 -1 0 1 2 3 4 5 g/kg Analysis increment fields (1h forecast error correction) RUC analysis 2200 UTC 29 Oct 1999 Sfc virtual pot tempSfc water vapor mix ratio

33. 33 Wind analysis increment fields (forecast error correction) - RUC analysis 2200 UTC 29 Oct 1999

34. 34 Vertical cross-section – 2200 UTC 29 Oct 99 RUC 3-d analysis Need for 3-d consistency to initialize model, other diagnostics SLC CYS

35. RUC-2 Model Prognostic variables –Dynamic - (Bleck and Benjamin, 93 MWR)  v,  p between levels, u, v –Moisture - (MM5 cloud microphysics) q v, q c, q r, q i, q s, q g, N i (no. conc. ice particles) –Turbulence - (Burk-Thompson, US Navy, 89 JAS) –Soil - temperature, moisture - 6 levels (down to 3 m) –Snow - water equivalent depth, temperature (soil/snow/veg model - Smirnova et al., 1997 MWR)

36. RUC-2 Model, cont. Numerics –Continuity equation flux-corrected transport (positive definite) –Advection of  v, all q (moisture) variables Smolarkiewicz (1984) positive definite scheme –Horizontal grid Arakawa C –Vertical grid Non-staggered, generalized vertical coordinate currently set as isentropic-sigma hybrid

37. RUC-2 Model, cont. Cumulus parameterization –Grell (Mon.Wea.Rev., 1993) –simplified (1-cloud) version of Arakawa- Schubert –includes effects of downdrafts Digital filter initialization (Lynch and Huang, 93 MWR) –+/- 40 min adiabatic run before each forecast

38. 38

39. 39 RUC Digital Filter Initialization 40  t forward 40  t backward - digital filter avg of model values Produces much smoother 1-h fcst Mean absolute sfc pres tendency each  t in successive RUC runs

40. 40 Processes in RUC2/MM5 microphysics (Reisner, Rasmusssen, Bruintjes, 1998, QJRMS)

41. 41 RUC2 case study - Quebec/New England ice storm - 9 Jan 1998 500 mb height/vorticity - 9h RUC2 fcst valid 2100 UTC

42. 42 RUC2 9h fcst - Surface temp (image), MSLP (beige isobars)

43. 43 YUL N-S cross-section - temperature (isopleths, int = 2 deg C, solid for > 0) RH (image), 9h RUC2 forecast

44. 44 Montreal ice storm - 9h RUC2 forecast valid 2100 9 Jan 98. N-S cross sections of RUC2 microphysics | YUL/Montreal Water vapor mixing ratio /  Cloud water mixing ratio Graupel mixing ratio Rain water mixing ratio

45. 40 km RUC versus 32 km Eta June-July 1999

46. 40 km RUC versus 32 km Eta June-July 1999

47. RUC vs. Eta 12-h fcsts 250mb RMS vector error From 80km grids for both models RUC uses 24h Eta for lateral boundary conditions 12 11 10 9 8 7 6 5 Comparable skill, potential for ensembles

48. 48 RUC 1, 3, 6, 12h forecasts valid at same time Better wind and temperature forecasts with use of more recent asynoptic data (against 0000 and 1200 UTC rawinsonde data)

49. 49 RUC/MAPS Land-surface Process Parameterization (Smirnova et al. 1997, MWR; 1999, JGR) Ongoing cycle of soil moisture, soil temp, snow cover/depth/temp) 2-layer snow model

50. 50 Addition of high-resolution EOS vegetation-type data to current 40km MAPS - September 1999 Previous MAPS vegetation New vegetation – BATS classes

51. 51 RUC/MAPS cycling of soil/snow fields - soil temperature, soil moisture - snow water equivalent, snow temperature MAPS snow water equivalent depth (mm) 5 Jan 1999 1800 UTC NESDIS snow cover field 5 Jan 1999 2200 UTC 1” 2” 3” 4” 5”

52. RUC2 Output Files, cont. Significant changes to RUC AWIPS output Already started after NCEP fire –AWIPS files produced as each part of RUC is complete (analysis, 3h, 6h, 9h, 12h) rather than all produced after end of RUC forecast run –Hourly output of analysis and 3h fcst –New variables added - vertical velocity (3-d), lots of 2-d grids –New 2-d variables - cloud top/base, visibility, gust speed, PBL height, conv cloud top, eq level, pres(max  e ) Likely to start within next few months –212 grids (236 subset of 212 - 151x113 RUC domain) will be available (not certain of comms yet)

53. 53 Examples of new diagnostic fields from RUC VisibilitySfc wind gust speed

54. 54 RUC visibility and ceiling vs. METAR IFR/MVFR 1700 UTC 4 Dec 1999

55. 55 Maintenance of operational RUC  Operational production at FSL of backup RUC products in real time from 1 Oct thru 15 Nov 1999  Software and scripts developed and implemented on separate SGI Origin for backup.  Monitoring, verification, new web sites, web forum  Daily coordination with NCEP and NWS/OSO

56. 56

57. 57 1-h fcst w/o GOES cloud assim 1-h fcst w/ hourly GOES cloud assim NESDIS cloud-top (verification) RUC/MAPS 1-h cloud-top fcsts with and without GOES cloud-top assimilation (clearing and building) (1200 UTC 14 May 1999)

58. 58 1-h MAPS cloud-top fcst with previous GOES assimilation -- valid 18z 28 Oct 99 Visible satellite image at 1745z 28 Oct 99 Correspondence between MAPS cloud fcsts and sat images - improved with GOES cloud-top assimilation

59. 59 Control - no cloud analysis Parallel - with cloud analysis September 1999 - fall Significant improvement in RUC cloud-top forecasts with cloud analysis, esp. for 1-h forecasts, but smaller but consistent improvement even in 12-h forecasts 0.7 0.5 0.3 Cloud-top verification with and without initial cloud analysis - correlation coefficient between RUC forecasts and NESDIS cloud-top pressures Julian date

60. 60 Verification of MAPS cloud-top fcsts against NESDIS product Frequency scatter plot for each MAPS grid point Cloud tops valid Sunday 21 Nov 99 1800 UTC pres 9-h fcsts 1-h fcsts Parallel run w/ GOES Control run no GOES

61. 61 Impact of GOES cloud-top assimilation in MAPS parallel cycle test - July-August 1999 Improved 3h RH forecasts with GOES cloud assimilation, especially at 300-500 hPa. Less impact at 850-700 hPa. w/ GOES No GOES

62. 62 Visible satellite image at 1745z 28 Oct 99 NESDIS Cloud-top product (sounder-based) 1800z 28 Oct 99

63. 63 Addition of national radar data to RUC cloud analysis Access software for national radar (both 4km NEXRAD and 2km NOWRAD) data developed Initial comparisons between GOES cloud-top pressures and national radar data – both mapped to RUC 40km grid

64. Apr 99 emergency change for RUC2 Correctly uses raob sig-level temp/dewpoint data now. Previously, missed sig-level T/Td data (TTBB) and forced in linearly interpolated structures between mandatory levels. Significant improvement in RUC grid sounding structures and in overall RUC performance

65. May 99 post-proc fixes for RUC2 Bug/consistency fixes for diagnosis of sfc T/Td in RUC2. (fix to lapse rate range) –Biases in west US for T/Td reduced, 2 °C  0 –s.d. temps over US from 2.0  1.4 °C (verification against METAR obs) CAPE- searches lowest 300 mb, not 180 mb More smoothing of isobaric winds in lower troposphere, near tropopause Use of NESDIS ice field Much faster running of RUC - 10 procs for all runs

66. 66 June 99 fix to veg fraction bug Vegetation fraction in RUC was erroneously set to zero due to integer/real problem (only a problem w/ NCEP RUC, not in FSL MAPS/RUC) Responsible for warm bias from 2100-0900 UTC increasing during May. Also resulted in dry bias and too little precip

67. 67 July/Sept/Nov/Dec 1999 fixes 26 July - fix to moisture in RUC boundary conditions from Eta - Eliminate erroneous precip near RUC boundaries especially over warm oceans 28 Sept – start IBM version of RUC – faster post-processing 21 Nov – fix canopy water cycling problem that had caused too moist soil for about 1 week Dec ? – 8 new variables in post-processing – visibility, cloud base/top, sfc wind gust, PBL height, conv. Cld top, equilibrium level, pres of max theta-e

68. RUC-2 Weaknesses Still some precip spin-up problem, despite cycling of cloud/precip variables, esp. for light precip/overrunning (1-3 hr late) Fix: Add cloud analysis - 1999 - 1st version, allow for cloud at RH < 100% Too much precip over warm oceans, too little near SE coast in cold season Dec 98 fix package helped some - work underway on fixing tendencies input to Grell convective parameterization Fix now running in backup RUC – look at web page prods Daytime convective precip in summer too widespread Upcoming fix on tendencies input to Grell scheme Fix now running in backup RUC

69. RUC-2 Weaknesses, cont. Convective precip forecasts miss many small areas, underforecast peak amounts. –Lower equitable threat score than Eta –more detailed than Eta Too much graupel near 0ºC Fix: with 20-km RUC (perhaps sooner), collaboration with FSL and NCAR on microphysics fixes Diurnal cycle of surface temperature a little too weak –a little too warm at night Dec 98 fix package - sfc flux change, radiation fix, GRIB precision to allow proper soil moisture cycling May 99 fix - improve diagnosis of sfc temp/Td diagnosis -- significant reduction in bias Upcoming fix to SW radiation 0-60 min phase delay Detailed (noisy?) output compared to other models, especially vertical velocity –Detail is probably realistic over terrain

70. Fixed RUC-2 Weaknesses Analysis sounding structure –irregular near ground if only sfc data assimilated Fix: analysis tuning (Dec 98) Fix: sig-level bug fix (Apr 99) ***************** CAPE/CIN –analysis values previously too high in high CAPE areas –jump between analysis and 1-h forecasts Fix: CAPE software (Dec 98) (May 99 - parcel search now in lowest 300 mb, not 180 mb layer)

71. RUC-2 Strengths Surface fields, especially surface winds –sfc files analysis and forecast small standard sfc fields plus precip, stability, precip type Topographically induced circulations –sea/lake breezes (scale too large but they’re there) –mtn/valley circulations –differential friction effects e.g. – Catalina eddy

72. RUC-2 Strengths, cont. Precipitation fields –more detailed than Eta (lower FAR but lower POD) Snow accumulation –explicit, not diagnosed (from MM5 microphysics) Precipitation type –uses explicit hydrometeor mixing ratios/fall rates Upper-level features –hybrid  /  coordinate –winds, PV, temps, fronts, more coherent vorticity structures on isobaric surfaces

73. RUC-2 Strengths, cont. Lower tropospheric temp/RH –good fcst sounding structure (esp. after 4/99 fix) –hybrid coordinate Soil/hydro fields –soil moisture - cycled in 6-level soil model –surface runoff, canopy water, dew formation, etc. Vertical velocity –available in RUC-2 –good mtn wave depiction, frontal features Hourly analyses –available much sooner than RUC-1 grids

74. 74 Mtn wave comparison - MesoEta vs. RUC2 RUCMesoEta Theta

75. 75 MesoEtaRUC U - component Mtn wave comparison - MesoEta vs. RUC

76. 76 W - vertical velocity Mtn wave comparison - MesoEta vs. RUC

77. 77 20km RUC/MAPS topography - 2000 Will use 20km versions of EOS veg data 3-d STATSGO soil data improved data assimilation (sat cloud products, 3dVAR, later - radar, sfc cloud data, lightning, GPS IPW) Subset of full domain

78. 78 13km RUC - 12h forecast - start 0000 UTC 27 October 1997 Precipitation Surface winds

79. 79 13km RUC - 6h forecast valid 06Z 27 Oct 97 6-h precipitation (cm), wind speed (m/s) in cross-section 10 20 25

80. The Future of the RUC Transfer of current 40km RUC2 to IBM SP –completed Sept 1999 –faster, distributed post-processing 20 km 1 hr version on IBM SP –Probably by summer 2000 –3-d variational analysis –Cloud/hydrometeor analysis using satellite combined with explicit cloud fcsts in RUC-2 Later, assimilation of new data sets: radar, sfc cloud obs, sat. cloudy/clear radiances (GOES/POES), hourly precipitation analyses, WSR-88D radial winds, lightning, GPS precipitable water, sat water vapor winds

81. The Future of the RUC, cont. –Improved physical parameterizations, including cloud microphysics (freezing drizzle), surface physics (frozen soil, high-resolution soil and surface data sets), and turbulence physics Higher resolution versions –13-15 km/60 level - 2001 Applications to air quality, coupled air chemistry? Extensive NAOS observation sensitivity tests WRF version of RUC

82. The Future of the RUC, cont. Non-hydrostatic  z model under development –Generalized vertical coordinate –Nudging of coordinate surfaces toward “grid generator” can be set as smoothed quasi-isentropic hybrid coordinate – treats sub~20km variations (convective clouds, breaking mountain waves) w/ quasi-horizontal coordinates –treats >20km variations w/  z coordinates –Collaboration between University of Miami (Rainer Bleck, Zuwen He), FSL (John Brown, Stan Benjamin), and NCAR (Bill Skamarock) – Part of WRF model (Weather Research and Forecast - NCAR/FSL/NCEP/CAPS) effort - a generalized vertical coordinate option. –WRF-based RUC probably by 2005-6 at 5-8 km scale –30-min cycle or finer?

83. 83 Quasi-isentropic option for WRF non-hydrostatic model Breaking mountain wave simulation - 2 km horizontal resolution Sigma-z versionQuasi-isentropic version Thick -  Thin - coordinate surfaces

84. 84 Rapid Update Cycle – Present and Next Version 1999 Operations2000-01 Operations Resolution40 km, 40  levels20  13-15 km, 40  50-60  levels AnalysisOptimal interpolation on3-d variational technique on generalized on generalized  surfaces  surfaces, hydrometeor analysis w/ GOES…, use raw instead of interp. obs AssimilationIntermittent 1-h cycleIntermittent 1-h cycle Stable cloudsMixed-phase cloud microphysics MM5),Improved microphysics, / precipitation explicit fcst of cloud water, rain water, addition of drizzle snow, ice, graupel, no. concentration of ice particles Sub-grid-scaleGrell (1993)Modified Grell, scale dependence, precipitation shallow convection, interaction w/ cloud microphysics TurbulenceBurk-Thompson explicit TKE schemeRefined Burk-Thompson or e-  RadiationMM5 LW/SW scheme, f(hydrometeors)Refined MM5 scheme Land-sfc processes6-level soil/veg model (Smirnova, Add vertical soil type variability, 1997, 1999) w/ frozen soil, 2-layer snow improved cold season processes Sfc conditionsDaily 50km SST/14 km LST,Combine sat T skin, use 3-d soil type 0.14  monthly NDVI veg frac, cycled soil moisture/temp, snow depth/temp

85. Feedback Send feedback/questions on RUC performance to the RUC discussion forum. Invite us to workshops. http://maps.fsl.noaa.gov/forum/eval 303-497-6387 benjamin@fsl.noaa.gov