North American Regional Reanalysis (NARR) Revised: 31 May 2023 ________________________________________________________________________________ The NARR archive may be accessed by a ftp client or by a web browser: 1) If you want to use a ftp client, Windows PC users may use WinSCP, FileZilla, etc. that support passive mode. MacOS and Linux users may use the ftp command. Connect your ftp client to ftp.arl.noaa.gov using anonymous and your email address for the username and password, respectively and change directory to /archives/narr. Note if you are using multiple ftp connections, limit the number of concurrent connections equal to or less than two. Otherwise, your access to our ftp server may be blocked off. 2) If you are using a web browser, point it to https://www.ready.noaa.gov/data/archives/narr. It may take a few minutes or longer for the webpage to display. ________________________________________________________________________________ This directory contains NARR (North American Regional Reanalysis) meteorological data from 1979 to 2019. The data is available on a 3 hourly, 32 km grid. The NARR project is an extension of the NCEP Global Reanalysis which is run over the North American Region. The NARR model uses the very high resolution NCEP Eta Model (32km/45 layer) together with the Regional Data Assimilation System (RDAS) which, significantly, assimilates precipitation along with other variables. The improvements in the model/assimilation have resulted in a dataset with substantial improvements in the accuracy of temperature, winds and precipitation compared to the NCEP-DOE Global Reanalysis 2. ARL PROCESSING: 3 hourly, 32 km data on pressure surfaces, in GRIB1 format, were downloaded from NOAA's National Operational Model Archive & Distribution System (ftp://nomads.ncdc.noaa.gov/NARR/) and converted to ARL format. The processed files were aggregated into monthly files with the following naming convention: NARRyyyymm, where yyyy is the year (e.g. 1987) and mm is the month (e.g. 12). Following is the description of the data grid and the meteorological variables Vert. Coordinate 2 Pole Lat. 90.00 Pole Lon. 0.00 Ref. Lat. 50.00 Ref. Lon. -107.00 Ref. Grid 32.46 Orientation 0.00 Cone Angle 50.00 Sync X 1.00 Sync Y 1.00 Sync Lat. 6.98 Sync Lon. -143.76 Special 0.00 Numb. Lat. 309 Numb. Lon. 237 Numb. Vertical layers 24 Surface variables 0.0000 11 TPP3 DSWF HPBL LHTF PRSS MSLP SHTF TCLD T02M U10M V10M level 1 1000.0 7 UWND VWND HGTS TEMP WWND SPHU TKEN level 2 975.0 7 UWND VWND HGTS TEMP WWND SPHU TKEN level 3 950.0 7 UWND VWND HGTS TEMP WWND SPHU TKEN level 4 925.0 7 UWND VWND HGTS TEMP WWND SPHU TKEN level 5 900.0 7 UWND VWND HGTS TEMP WWND SPHU TKEN level 6 875.0 7 UWND VWND HGTS TEMP WWND SPHU TKEN level 7 850.0 7 UWND VWND HGTS TEMP WWND SPHU TKEN level 8 825.0 7 UWND VWND HGTS TEMP WWND SPHU TKEN level 9 800.0 7 UWND VWND HGTS TEMP WWND SPHU TKEN level 10 775.0 7 UWND VWND HGTS TEMP WWND SPHU TKEN level 11 750.0 7 UWND VWND HGTS TEMP WWND SPHU TKEN level 12 725.0 7 UWND VWND HGTS TEMP WWND SPHU TKEN level 13 700.0 7 UWND VWND HGTS TEMP WWND SPHU TKEN level 14 650.0 7 UWND VWND HGTS TEMP WWND SPHU TKEN level 15 600.0 7 UWND VWND HGTS TEMP WWND SPHU TKEN level 16 550.0 6 UWND VWND HGTS TEMP WWND SPHU level 17 500.0 6 UWND VWND HGTS TEMP WWND SPHU level 18 450.0 6 UWND VWND HGTS TEMP WWND SPHU level 19 400.0 6 UWND VWND HGTS TEMP WWND SPHU level 20 350.0 6 UWND VWND HGTS TEMP WWND SPHU level 21 300.0 6 UWND VWND HGTS TEMP WWND SPHU level 22 200.0 6 UWND VWND HGTS TEMP WWND SPHU level 23 100.0 6 UWND VWND HGTS TEMP WWND SPHU Field Units Label Accumulated precipitation (3 h accumulation) m TPP3 Downward short wave radiation flux W/m2 DSWF PBL height m HPBL Latent heat net flux at surface W/m2 LHTF Pressure at surface hPa PRSS Pressure reduced to mean sea level hPa MSLP Sensible heat net flux at surface W/m2 SHTF Total cloud cover % TCLD Temperature at 2m AGL K TO2M U-component of wind at 10 m AGL m/s U10M V-component of wind at 10 m AGL m/s V10M U-component of wind with respect to grid m/s UWND V-component of wind with respect to grid m/s VWND Geopotential height gpm* HGTS Temperature K TEMP Pressure vertical velocity hPa/s WWND Specific humidity g/Kg SPHU Turbulent kinetic energy Joul TKEN * geopotential meters Reference: National Centers for Environmental Prediction/National Weather Service/NOAA/U.S. Department of Commerce, 2015: NCEP North American Regional Reanalysis (NARR). Research Data Archive at the National Center for Atmospheric Research, Computational and Information Systems Laboratory, Boulder, CO. [Available online at http://rda.ucar.edu/datasets/ds608.0/.]