Rapid Refresh (RAP)High-Resolution Rapid Refresh (HRRR) model, which is also updated hourly and covering a smaller geographic domain.
- RAPv1 - implemented 1 May 2012 at NCEP (replacing the Rapid Update Cycle - RUC )
- RAPv2 - implemented 25 Feb 2014 at NCEP
- RAPv3 - scheduled for 23 Aug 2016 at NCEP,running in real-time demo at ESRL and in real-time parallel at NCEP.
NCEP RAPv3/HRRRv2 parallel evaluation has started
The NCEP RAP version three/HRRR version two (RAPv3/HRRRv2) parallel 30-day evaluation has started as of 12 UTC 14 July 2016. Forecast grids are being produced from a parallel configuration of the RAPv3/HRRRv2 running on the NCEP computer system. These NCEP GRIB2 forecast grids are being produced and made available in real-time for all 24 runs per day. This NCEP RAPv3/HRRRv2 parallel configuration is not yet officially operational and will remain in a parallel status throughout this 30-day evaluation period. The estimated current date for the operational implementation of the RAPv3/HRRRv2 is 12 UTC 23 August 2016, although this date is still subject to change. We encourage users of the operational and/or experimental RAP and HRRR data to begin evaluation and use of these NCEP RAPv3/HRRRv2 parallel grids at your earliest convenience.
(1) GRIDS: The NCEP RAPv3/HRRRv2 parallel GRIB2 grids are available at:
(2) WEB GRAPHICS: The NCEP RAPv3/HRRRv2 parallel web graphics are available at:
Additional web graphics produced from ESRL (not 24/7 availability) for the NCEP RAPv3/HRRRv2 are available from:
(3) INFORMATION: The technical information notice (TIN) related to the underlying science and output changes between the operational RAPv2 and the parallel RAPv3 along with the operational HRRRv1 and the parallel HRRRv2 are contained in the document:
Experimental HRRRv2/RAPv3 implemented at ESRL 1 Jan 2015.
- significant further improvement for summer/winter storm environment
- advanced physics with WRFv3.6, assimilation, improved initial conditions for HRRR.
- More information in graphic summary, changes shaded red. and in HRRR/RAP July 2015 presentation to NCEP.
- Complete RAP (v1-v3) description in Benjamin et al. 2016, A North American Hourly Assimilation and Model Forecast Cycle: The Rapid Refresh. Mon. Wea. Rev., 144, 1669-1694.
Recent RAP/HRRR presentations
- HRRR/RAP July 2015 presentation to NCEP
- Experimental 2014-very-early-version-RAPv3 implementation at ESRL completed on 10 April 2014 - improved storm environment, assimilation. Preliminary ESRL RAPv3/HRRRv2 info here.
- From NWS RAPv2 webinar - Feb 2014 .
- Additional information on the RAPv2 implementation at NCEP is in this NWS Technical Implementation Note (TIN, amended 15 Jan 2013). .
The NCEP Rapid Refresh (currently RAPv2) uses
a RAP-specific configuration of the WRF model with ARW core
with this physics suite (as of RAPv2): Grell-G3 convection,
Thompson/NCAR microphysics, RRTM longwave radiation, Goddard
shortwave radiation, MYNN-Olson turbulent mixing, RUC-Smirnova
- a RAP-configuration of the Gridpoint Statistical Interpolation (GSI) analysis system. (with cloud/hydrometeor analysis added, similar to RUC)
- 13-km horizontal resolution, 50 vertical levels, ptop=10hPa, sigma vertical coordinate
- rotated lat-lon projection grid (change from previous Lambert conformal grid in July-Oct 2010) with a 759x567 mass-point domain (Arakawa C grid) More domain info here.
- Uses 1/12-deg NCEP sea-surface temperatures
- Output grids to be available from NCEP (including those exactly matching grids currently available from RUC.
- Rapid Refresh (RAPv3, running at ESRL in real-time demo in early 2015)
uses the following options. Some key differences from RAPv2
are identified below and in this
graphic summary, changes shaded red.
- Model core: WRFv3.6.1+ instead of WRFv3.4.1+ (WRFv3.2.1 used in RAPv1)
- Model physics: MYNN-Olson boundary-layer scheme, aerosol-aware Thompson cloud microphysics (v3.6) improved v3.6 RUC/Smirnova land-surface model (9-level)
- Surface fields: MODIS land-surface data including fractional coverage
- Numerics: 5th-order vertical advection, w-damping upper boundary condition.
- Data assimilation: Ensemble/hybrid/GSI data assimilation (using GFS assimilation ensemble and GSI)
- Observations assimilated: GOES cloud building, lightning (proxy for radar reflectivity), pseudo-PBL temp/moisture obs from 2m temp/dewpoint obs, soil moisture adjustment within data assimilation, improved radar assimilation.
- The ESRL RAP contributes to initialize the 3km High-Resolution Rapid Refresh (HRRR), providing a background for a HRRR-internal 1-h assimilation cycle with 15-min radar and 3-km GSI before the HRRR is initialized.
High-Resolution Rapid Refresh (HRRR)
- A experimental 3-km hourly updated nest inside of the 13km Rapid Refresh
(using the 13km RAP as parent model followed by 3-km data assimilation).
- HRRR home page / info
- Real-time products from 3km HRRR
- 25 Feb 2014. NCEP implementation of RAP version 2 to replace RAPv1 occurred as planned at 12z 25 Feb 2014. Summary on upcoming RAPv2 implementation to NWS Regions - 18 Feb 2014 . -- NWS Technical Implementation Note (TIN). .
- 8 Apr 2013. Major upgrade to ESRL RAP (and HRRR) over Jan-April 2013 period, details here.
1 May 2012.
RAP implementation occurred
at 12z that day. The last RUC run was at 11z that day
See latest NWS TIN bulletin on RAP implementation at
- 15 Mar 2012.Updated briefing on Rapid Refresh.
- high-frequency updated (every 1h) short-range weather model forecasts (out to 18h) in support of aviation, severe weather, energy, and other mesoscale weather forecast users
high-frequency (every 1h) 3-d objective analyses
over all of North America,
assimilating the following types of observations:
- Commercial aircraft (including moisture data from WVSS-II sensors)
- 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
- Radar reflectivity (3-d)
- Surface reporting stations and buoys (including cloud, visibility, current weather)
- Mesonet (defer to RAP version 2)
- AMSU-A/B satellite radiances
- GOES satellite radiances (defer to RAP version 2)
- GPS total precipitable water estimates
- GOES cloud-top data (pressure and temperature)
- GOES high-density visible and IR cloud drift winds
- Lightning - defer to RAPv2 (used in ESRL RAP since Jan 2012)
- Special wind-energy observations - defer to RAPv2 (used in ESRL RAP)
The key features of the Rapid Refresh include:
Access to real-time and archive RAP grids