The Rapid Update Cycle (RUC)
- The RUC is a NOAA/ NCEP
operational weather prediction system
comprised primarily of
- A numerical forecast model (using isentropic-sigma hybrid vertical coordinate) and
- An analysis/assimilation system to initialize that model.
- Developed to serve users needing frequently updated short-range weather forecasts, including those in the US aviation community and US severe weather forecasting community.
- The Rapid Refresh (RR) is the next-generation version of the 1-h cycle system, planned to replace the current RUC by early 2010.
News items
- 31 Mar 2009. NCEP implementation at 12z with improved snow cover and improved cloud analysis, see Info PDF here. - February RUC forum post on this topic
- 16 Dec 2008. TAMDAR data added to operational RUC at NCEP
- 17 Nov 2008. RUC upgrade implementation at NCEP Assimilation of radar reflectivity added, longwave radiation changed to RRTM scheme, convection (Grell-Devenyi) changes. Extended RUC upgrade ppt here for pre-implementation briefing
- 8 Jan 2008. RUC crisis change for improved cloud/vis assimilation, wind gust, precip type. Post on RUC forum , PDF
- 11 Dec 2007. RUC/RR summary Powerpoint/pdf presented at NCEP Production Suite Review meeting.
- 4 Dec 2007. 13km/hourly RUC grids became available via NOAAPort and Family of Services. See RUC Forum post
- Reflectivity real-time products available for devRUC13 and backup RUC13 uns since April 2007.
- 4 April 07 - 3-d radar reflectivity data assimilated hourly in experimental devRUC13 since Feb07 and now in backup RUC13 as now. An example of the effect of radar reflectivity assimilation in available here
- 28 June 2005 --
13km RUC operational implementation at NCEP --
-- Higher resolution, additional observation types assimilated (GPS PW, METAR cloud/vis, RASS, improved use of GOES cloud-top), improved moisture analysis, improved cloud/precip physics. -
RUC journal articles available in Feb 2004 Monthly Weather Review.
Mesoscale Weather Prediction with the RUC Hybrid Isentropic Terrain-Following Coordinate Model. pages 473-494. [GSD PDF version]
An Hourly Assimilation-Forecast Cycle: The RUC. pages 495-518. [GSD PDF version]
- high-frequency (every 1h) short-range weather model forecasts (out to 12+ h) in support of aviation and other mesoscale weather forecast users
-
high-frequency (every 1h) 3-d objective analyses
over much of North America,
including the contiguous United States and
adjacent areas of Canada and Mexico, assimilating the following types of observations:
- Commercial aircraft, including regional aircraft data with moisture (TAMDAR)
- Radar reflectivity (3-d)
- Profiler related
- Wind profilers (404 and boundary-layer 915 MHz)
- VAD (velocity-azimuth display) winds from NWS WSR-88D radars
- RASS (Radio Acoustic Sounding System)
- Rawinsondes and special dropwinsondes
- Surface
- Surface reporting stations and buoys (including cloud, visibility, current weather)
- Mesonet
- Satellite
- GPS total precipitable water estimates
- GOES cloud-top data (pressure and temperature)
- GOES total precipitable water estimates
- SSM/I total precipitable water estimates
- GOES high-density visible and IR cloud drift winds
- Experimental
- Lightning - experimental
- NASA Langley cloud products including water/ice path
- a hybrid isentropic-sigma vertical coordinate.
The key features of the RUC include:
Other RUC Information, Real-Time and Archived Data
Real-time RUC gridded data available from
- NCEP ftp site including 13km output resolution grids available in GRIB2 since summer 2007, see ftp://ftpprd.ncep.noaa.gov/pub/data/nccf/com/ruc/prod/
- More info - NOAA/NCEP - Real-time operational RUC grids
- NOAA/NWS/TG server NOAA/NWS/TG (Telecommunications Gateway) - real-time RUC grids
Archived RUC gridded data available from:
- Background on RUC data from DOE/ARM Program DOE/ARM web page on RUC gridded data
- NOMADS/NCDC/NOAA
- NASA Langley archived RUC soundings
- NCAR/UCAR - Access to archived GSD/FSL RUC/MAPS data for UCAR registered users (use search for 'MAPS')
Information on gridded data
- RUC grid files - Information on contents
-
RUC13 GRIB table-updated 17 Nov 2008
with RUC upgrade
(see RUC20 table for GRIB document links) - Previous RUC13 GRIB table as of Sept 2005
- RUC20 GRIB table with GRIB document links
- RUC analysis obs and background error specifications
Model fixed fields - topography, etc.
-
Download RUC fixed fields (ASCII) and software
- 13km topography, mini-topography, lat/lon, land-use, roughness length, soil type
- 5km RTMA topography (used for RUC-RTMA downscaling)
- 20-km, 40-km and 60-km topography or latitude/longitude
- 20km land-use, look-up table for roughness length, albedo, emissivity
- software to convert from RUC native coordinates/variables to isobaric coordinates/variables
- 13-km RUC terrain elevation map
- 20-km RUC (pre June05) topography map
- NCEP daily sea-surface temperature file currently used in RUC
- Lightning coverage - Env Canada
Snow/ice data from RUC, NOAA-NESDIS, NOAA-NOHRSC, Environment Canada
-
Snow cover / depth analyses for comparison with RUC cycled snow cover/water equivalent
- NESDIS daily snow cover (obs only, updated daily, NESDIS-NOAA snow analyses via Env Canada snow depth analysis
- NOHRSC-NOAA snow analyses
- RUC snow cover (operational - NCEP) (cycled using RUC land-surface model, updated hourly)
- RUC snow cover (development - ESRL)
Other sites to obtain real-time RUC-based weather graphics
- RUC Meteograms from NCEP/EMC
- NCEP/NCO web page w/RUC fields.
- NCEP/Manikin web page w/ RUC output for convective forecasting.
- Storm Prediction Center Composite Map (CompMap) using RUC data -- can overlay different fields in a Java script
- Comprehensive RUC Graphics from NCAR/RAP/Greg Thompson, including cloud depictions
- Aviation grids of winds, icing, and turbulence using RUC (0-12h) from ADDS at Aviation Weather Center
Stan.Benjamin@noaa.gov (303)497-6387