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Rapid Refresh (RAP)

A 3-D animation of RAP forecast data valid from 0000 UTC through 1800 UTC on July 11, 2012

An animated 3-D plot of RAP forecast data valid from 0000 UTC through 1800 UTC on July 11, 2012. This forecast loop shows simulated composite radar reflectivity on the surface and a 25 m/s isosurface of wind speeds aloft. Stretching from Hudson's Bay to the Atlantic is a vertical profile of relative humidity, red showing high relative humidity and blue showing drier air. This image was generated with Unidata's Integrated Data Viewer (IDV).

The Rapid Refresh (RAP) numerical weather model took the place of the Rapid Update Cycle (RUC) on May 1, 2012. Run by the National Centers for Environmental Prediction (NCEP), RAP runs with two versions. The first generates weather data on a 13-km (8-mile) resolution horizontal grid and the second, the High-Resolution Rapid Refresh (HRRR), generates data down to a 3-km (2-mile) resolution grid for smaller regions of interest. RAP forecasts are generated every hour with forecast lengths going out 18 hours. Multiple data sources go into the generation of RAP forecasts: commercial aircraft weather data, balloon data, radar data, surface observations, and satellite data. More information on the RAP and HRRR are available at the RAP home page. RAP data, but not HRRR data, are available for download through the National Model Archive and Distribution System (NOMADS).

Product Types

RAP Analysis

Model	Grid/Scale	Period of Record	Model Cycle	Output Timestep	Data Access Links
RAP	130 (13km) - Domain	01May2012–Present	24/day: 00, 01, 02,... 23UTC	+000 and +001 hours	HTTPS TDS AIRS
RAP	252 (20km) - Domain	01May2012–Present	24/day: 00, 01, 02,... 23UTC	+000 and +001 hours	HTTPS TDS AIRS
RUC	130 (13km) - Domain	01Jan2005–01May2012	24/day: 00, 01, 02,... 23UTC	+000 and +001 hours	TDS AIRS
RUC	252 (20km) - Domain	01Jan2005–01May2012	24/day: 00, 01, 02,... 23UTC	+000 and +001 hours	TDS AIRS

RAP Forecasts

Model	Grid/Scale	Period of Record	Model Cycle	Output Timestep	Data Access Links
RAP	130 (13km) - Domain	01May2012–Present (approx. one year to present online)	24/day: 00, 01, 02,... 23UTC	Hourly, +000 to +018 hours	HTTPS TDS AIRS
RAP	252 (20km) - Domain	01May2012–Present (approx. one year to present online)	24/day: 00, 01, 02,... 23UTC	Hourly, +000 to +018 hours	HTTPS TDS AIRS
RUC	130 (13km) - Domain	01Jan2005–01May2012	24/day: 00, 01, 02,... 23UTC	Hourly, +000 to +012 hours	AIRS
RUC	252 (20km) - Domain	12Feb2008–01May2012 (GRIB2)	24/day: 00, 01, 02,... 23UTC	Hourly, +000 to +012 hours	AIRS
RUC	252 (20km) - Domain	01Jan2005–21Feb2008 (GRIB1)	24/day: 00, 01, 02,... 23UTC	Hourly, +000 to +012 hours	AIRS
RUC	236 (40km) - Domain	01May2002–05Jul2005	24/day: 00, 01, 02,... 23UTC	Hourly, +000 to +012 hours	HTTPS
RUC	211 (81km) - Domain	01May2002–05Jul2005	24/day: 00, 01, 02,... 23UTC	3-hourly, +000 to +012 hours	HTTPS

Data Usage Notes

April 2003: RUC Grid 211 Forecast Hour 02 Labeled as Analysis Field

Messages for RUC2 will contain multiple records and one of the records will contain data from a forecast hour. The messages below belong to the RUC2 grid 236 2200UTC model runs on April 5th and April 6th of 2003. In the headers below, octet 4 indicates the forecast hour. The letter "A" indicates the 00 hour analysis, but according to wgrib the messages contain records with a 2-hr forecast.

YUWA98_KWBG_20030405_2200

1:21:d=03040522:UGRD:10 m above gnd:anl:NAve=0

2:19332:d=03040522:USTM:sfc:anl:NAve=0

3:38643:d=03040522:USTM:sfc:2hr fcst:NAve=0

YVWA98_KWBG_20030405_2200

1:21:d=03040522:VGRD:10 m above gnd:anl:NAve=0

2:19332:d=03040522:VSTM:sfc:anl:NAve=0

3:38643:d=03040522:VSTM:sfc:2hr fcst:NAve=0

YWWA98_KWBG_20030405_2200

1:21:d=03040522:CAPE:sfc:anl:NAve=0

2:27864:d=03040522:var180:sfc:anl:NAve=0

3:38643:d=03040522:var180:sfc:2hr fcst:NAve=0

March 2003: All RUC Grid 211 Analysis Fields Labeled as GFS-AVN

Messages from the RUC model grid 211 analysis fields have WMO headers that indicate they are from the GFS-AVN model. All the RUC grid 211 forecast hour 00 messages are missing because they are stored with the GFS-AVN grid 211 forecast hour 00 data. In the example below the "KWBC" in the WMO header indicates the GFS-AVN model, but the process id "86" indicates the RUC model.

nomads3.ncdc.noaa.gov 51: wgrib -V YVQA99_KWBC_20030801_0000

rec 1:21:date 2003080100 VGRD kpds5=34 kpds6=100 kpds7=1000 levels=(3,232)

grid=211 1000 mb anl: bitmap: 1713 undef

VGRD=v wind [m/s]

timerange 0 P1 0 P2 0 TimeU 1 nx 93 ny 65 GDS grid 3 num_in_ave 0 missing 0

center 7 subcenter 0 process 86 Table 2

Lambert Conf: Lat1 12.190000 Lon1 -133.459000 Lov -95.000000

Latin1 25.000000 Latin2 25.000000 LatSP 0.000000 LonSP 0.000000

North Pole (93 x 65) Dx 81.271000 Dy 81.271000 scan 64 mode 8

min/max data -11.6 9.8 num bits 8 BDS_Ref -116 DecScale 1 BinScale 0