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Operational Use of the Rapid Update Cycle. Stan Benjamin - NOAA/FSL [email protected] http://maps.fsl.noaa.gov - RUC/MAPS web page. COMAP Symposium 16 December 1999. The 1-h Version of the RUC. Data cutoff - +20 min, 2nd run at +55 min at 0000, 1200 UTC. RUC/MAPS Purpose.

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operational use of the rapid update cycle

Operational Use of the Rapid Update Cycle

Stan Benjamin - NOAA/FSL

[email protected]

http://maps.fsl.noaa.gov

- RUC/MAPS web page

COMAP Symposium

16 December 1999

slide2

The 1-h Version of the RUC

Data cutoff - +20 min, 2nd run at +55 min at 0000, 1200 UTC

slide3

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
what runs where
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)

uses of the ruc
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
hourly data for 40 km maps ruc 2
Hourly Data for 40 km MAPS/RUC-2

Data Type ~Number Freq. Use

Rawinsonde (inc. special obs) 80 /12h NCEP and FSL

WPDN/NPN profilers 31 / 1h NCEP and FSL

- 405 MHz

Boundary layer profilers 15 / 1h FSL only

RASS (WPDN and PBL) 15 / 1h FSL only

VAD winds (WSR-88D) 110-130 / 1h **NCEP & FSL

Aircraft (ACARS)(V,temp) 700-3000 / 1h NCEP and FSL

Surface - land (V,psfc,T,Td) 1500-1700 / 1h NCEP and FSL

Buoy 100-200 / 1h NCEP and FSL

**not used since 1/99 in RUC

or EDAS pending QC issues

Yellow items new for RUC-2

hourly data for 40 km maps ruc 2 cont
Hourly Data for 40 km MAPS/RUC-2 (cont).

Data Type ~Number Freq. Use

GOES precipitable water 1000-2500 / 1h NCEP and FSL

GOES high-density cloud

drift winds

(IR, VIS, WV cloud top) 1000-2500 / 3h NCEP and FSL

SSM/I precipitable water 1000-4000 /2-6h NCEP only

Ship reports 10s / 3h NCEP only

Reconnaissance

dropwinsonde a few / variable NCEP only

Yellow items new for RUC-2

Real-time observation counts at http://maps.fsl.noaa.gov for RUC-2

and 40-km MAPS

slide11

Advantages of q Coords for

Data Assimilation

Analysis

- adaptive 3-d correlation structures and

analysis increments, esp. nearbaroclinic 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)

slide12

RUC hybrid-b levels - cross-section

Hybrid-b levels

- solid

q levels (every 6 K)

- dashed

No discontinuities

at q/stransitions

slide13

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

slide14

Rapid Update Cycle – Present and Next Version

1999 Operations 2000-01 Operations

Resolution 40 km, 40 q/s levels 2015 km, 40  50-60 q/s levels

Analysis Optimal interpolation on 3-d variational technique on generalized

on generalized q/s surfaces q/s surfaces, hydrometeor analysis w/

GOES…, use raw instead of interp. obs

Assimilation Intermittent 1-h cycle Intermittent 1-h cycle

Stable clouds Mixed-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-scale Grell (1993) Modified Grell, scale dependence,

precipitation shallow convection, interaction w/

cloud microphysics

Turbulence Burk-Thompson explicit TKE scheme Refined Burk-Thompson or e-

Radiation MM5 LW/SW scheme, f(hydrometeors) Refined MM5 scheme

Land-sfc processes 6-level soil/veg model (Smirnova, Add vertical soil type variability,

1997, 1999) w/ frozen soil, 2-layer snow improved cold season processes

Sfc conditions Daily 50km SST/14 km LST, Combine sat Tskin, use 3-d soil type

0.14 monthly NDVI veg frac, cycled soil

moisture/temp, snow depth/temp

ruc 2 analysis
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 psfc from height analysis increment at sfc
      • update u/v at all levels
      • Partial geostrophic balance – vertically dependent, weakest at surface
ruc 2 analysis cont
RUC-2 Analysis, cont.

- 3) univariate analyses

    • condensation pressure at all levels
    • v at all levels
    • update u/v near sfc and psfc (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)
ruc 2 analysis cont1
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 psfc
  • Background is usually previous 1 hr RUC forecast
slide18

Raob sounding RUC2 grid sounding

Close fit to observations in RUC2 analysis

slide19

Raob RUC after fix RUC before fix

7 April 99 significant-level fix in RUC-2

use of minimum topography for 2m t td fields from ruc2
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.

slide21

RUC2 topography fields

Minimum topo for 2m T/Td

Model topo

rucs 60 km hourly surface analyses same as awips msas
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
surface analyses forecasts in ruc 2
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
slide24

Divergence - 0900 UTC 20 Jan 98

(blue - conv, green/yellow - div)

RUC2 Surface Analysis Topographical features more

evident with model background

RUCS 60km surface analysis

Little consistency with nighttime drainage

slide25

Divergence - RUC2 Surface Analysis - 0600Z 19 April 96

Consistency with topographical features in model

(land/water roughness length variations in this case)

surface analyses forecasts in ruc 2 cont
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

ruc 2 use of surface data
RUC-2 use of surface data

All winds, sfc pressure obs used

T/Td used if abs (Pstation - Pmodel) < 70 mb

- about 90% west of 105ºW, 99% east of 105ºW

Eta48 Eta29 RUC40

FGZ 0 18 10

TUS 60 13 44

SLC 59 68 59

MFR 109 48 67

OAK 1815 25

SAN 12 5 23

DRA 42 29 34

GJT 98 105 65

RIW 104 27 16

GEG 4 11 1

GTF 26 4 14

UIL 14 9 11

SLE 50 15 22

BOI 55 21 24

GGW 29 13 5

VBG 5 32 3

|pmodel - pstn|

** within 5 mb of closest fit

slide28

RUC surface temperature forecasts

- verification against all METARs in RUC domain

Excellent analysis fit to surface obs (also wind, Td)

3-h forecast better than 3-h persistence

RMS error Bias (obs - forecast)

persistence

Validation time

Validation time

slide29

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.

slide32

-3 -2 -1 0 1 2 3 4 5 g/kg

Sfc virtual pot temp Sfc water vapor mix ratio

Analysis increment fields (1h forecast error correction)

RUC analysis

2200 UTC 29 Oct 1999

slide33

Wind

analysis increment fields (forecast error correction)

-

RUC analysis

2200 UTC 29 Oct 1999

slide34

SLC CYS

Vertical cross-section – 2200 UTC 29 Oct 99

RUC 3-d analysis

Need for 3-d consistency to initialize model,

other diagnostics

ruc 2 model
RUC-2 Model
  • Prognostic variables
    • Dynamic - (Bleck and Benjamin, 93 MWR)
      • v, p between levels, u, v
    • Moisture - (MM5 cloud microphysics)
      • q v, qc, qr, qi, qs, qg, Ni (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)

ruc 2 model cont
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
ruc 2 model cont1
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
slide39

RUC

Digital Filter

Initialization

40 Dt forward

40 Dt backward

- digital filter avg

of model values

Produces much

smoother 1-h fcst

Mean absolute sfc pres tendency each Dt in successive RUC runs

slide40

Processes in RUC2/MM5 microphysics

(Reisner, Rasmusssen, Bruintjes, 1998, QJRMS)

slide41

RUC2 case study - Quebec/New England ice storm - 9 Jan 1998

500 mb height/vorticity - 9h RUC2 fcst valid 2100 UTC

slide43

N-S cross-section - temperature (isopleths, int = 2 deg C, solid for > 0)

RH (image), 9h RUC2 forecast

YUL

slide44

Montreal ice storm - 9h RUC2 forecast valid 2100 9 Jan 98.

N-S cross sections of RUC2 microphysics

Water vapor mixing ratio / q

Cloud water mixing ratio

| YUL/Montreal

Graupel mixing ratio

Rain water mixing ratio

slide47

RUC vs. Eta 12-h fcsts

250mb RMS vector error

12

11

10

9

8

7

6

5

From 80km grids for both models

RUC uses 24h Eta for

lateral boundary conditions

Comparable skill, potential for ensembles

slide48

RUC 1, 3, 6, 12h forecasts valid at same time

(against 0000 and 1200 UTC rawinsonde data)

Better wind and temperature forecasts with use of

more recent asynoptic data

slide49

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

slide50

Previous MAPS vegetation New vegetation – BATS classes

Addition of high-resolution EOS vegetation-type data to current 40km MAPS

- September 1999

slide51

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”

ruc2 output files cont
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 qe)

Likely to start within next few months

    • 212 grids (236 subset of 212 - 151x113 RUC domain) will be available (not certain of comms yet)
slide53

Visibility Sfc wind gust speed

Examples of new diagnostic fields from RUC

slide54

RUC visibility and ceiling

vs.

METAR IFR/MVFR

1700 UTC 4 Dec 1999

maintenance of operational ruc
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
slide57

RUC/MAPS 1-h cloud-top fcsts

with and without

GOES cloud-top assimilation

(clearing and building)

(1200 UTC 14 May 1999)

1-h fcst w/o GOES cloud assim

1-h fcst w/ hourly GOES cloud assim

NESDIS cloud-top (verification)

slide58

Visible satellite image at

1745z 28 Oct 99

1-h MAPS cloud-top fcst

with previous GOES assimilation

-- valid 18z 28 Oct 99

Correspondence between MAPS cloud fcsts and sat images

- improved with GOES cloud-top assimilation

slide59

Parallel- with cloud analysis

0.7

Control - no cloud analysis

0.5

0.3

Julian date

September 1999 - fall

Cloud-top verification with and without initial cloud analysis

- correlation coefficient between RUC forecasts and

NESDIS cloud-top pressures

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

slide60

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

Control run

no GOES

Parallel run

w/ GOES

1-h fcsts

pres

9-h fcsts

slide61

No GOES

w/GOES

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.

slide62

Visible satellite image at

1745z 28 Oct 99

NESDIS

Cloud-top product

(sounder-based)

1800z 28 Oct 99

slide63

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

apr 99 emergency change for ruc2
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
may 99 post proc fixes for ruc2
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
june 99 fix to veg fraction bug
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

july sept nov dec 1999 fixes
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

ruc 2 weaknesses
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
ruc 2 weaknesses cont
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
fixed ruc 2 weaknesses
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)

ruc 2 strengths
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
ruc 2 strengths cont
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
ruc 2 strengths cont1
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
slide74

MesoEta

RUC

Theta

Mtn wave comparison - MesoEta vs. RUC2

slide75

MesoEta

RUC

U - component

Mtn wave comparison - MesoEta vs. RUC

slide76

W - vertical velocity

Mtn wave comparison - MesoEta vs. RUC

slide77

Subset of full domain

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)
slide79

10

20

25

20

13km RUC - 6h forecast valid 06Z 27 Oct 97

6-h precipitation (cm), wind speed (m/s) in cross-section

the future of the ruc
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
the future of the ruc cont
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
the future of the ruc cont1
The Future of the RUC, cont.
  • Non-hydrostatic q-sz 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/q-sz 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?
slide83

Quasi-isentropic option for WRF non-hydrostatic model

Breaking mountain wave simulation - 2 km horizontal resolution

Sigma-z version Quasi-isentropic version

Thick - q

Thin -

coordinate

surfaces

slide84

Rapid Update Cycle – Present and Next Version

1999 Operations 2000-01 Operations

Resolution 40 km, 40 q/s levels 2013-15 km, 40  50-60 q/s levels

Analysis Optimal interpolation on 3-d variational technique on generalized

on generalized q/s surfaces q/s surfaces, hydrometeor analysis w/

GOES…, use raw instead of interp. obs

Assimilation Intermittent 1-h cycle Intermittent 1-h cycle

Stable clouds Mixed-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-scale Grell (1993) Modified Grell, scale dependence,

precipitation shallow convection, interaction w/

cloud microphysics

Turbulence Burk-Thompson explicit TKE scheme Refined Burk-Thompson or e-

Radiation MM5 LW/SW scheme, f(hydrometeors) Refined MM5 scheme

Land-sfc processes 6-level soil/veg model (Smirnova, Add vertical soil type variability,

1997, 1999) w/ frozen soil, 2-layer snow improved cold season processes

Sfc conditions Daily 50km SST/14 km LST, Combine sat Tskin, use 3-d soil type

0.14 monthly NDVI veg frac, cycled soil

moisture/temp, snow depth/temp

feedback
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

[email protected]

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