diff --git a/modules/data.atmosphere/DESCRIPTION b/modules/data.atmosphere/DESCRIPTION
index fceb2f2d7f..2adaaea92b 100644
--- a/modules/data.atmosphere/DESCRIPTION
+++ b/modules/data.atmosphere/DESCRIPTION
@@ -2,17 +2,21 @@ Package: PEcAn.data.atmosphere
 Type: Package
 Title: PEcAn Functions Used for Managing Climate Driver Data
 Version: 1.8.0.9000
-Authors@R: c(person("Mike", "Dietze", role = c("aut"),
-                     email = "dietze@bu.edu"),
-             person("David", "LeBauer", role = c("aut", "cre"),
-                     email = "dlebauer@email.arizona.edu"),
-             person("Carl", "Davidson", role = c("aut"),
-                     email = "davids14@illinois.edu"),
-             person("Rob", "Kooper", role = c("aut"),
-                     email = "kooper@illinois.edu"),
-             person("Deepak", "Jaiswal", role = c("aut"),
-                     email = "djaiswal@djaiswal.edu"),
-             person("University of Illinois, NCSA", role = c("cph")))
+Authors@R: c(
+    person("Mike", "Dietze", role = c("aut"),
+        email = "dietze@bu.edu"),
+    person("David", "LeBauer", role = c("aut", "cre"),
+        email = "dlebauer@email.arizona.edu"),
+    person("Carl", "Davidson", role = c("aut"),
+        email = "davids14@illinois.edu"),
+    person("Rob", "Kooper", role = c("aut"),
+        email = "kooper@illinois.edu"),
+    person("Deepak", "Jaiswal", role = c("aut"),
+        email = "djaiswal@djaiswal.edu"),
+    person("Chris", "Black", role = c("ctb"),
+        email = "chris@ckblack.org",
+        comment = c(ORCID="https://orcid.org/0000-0001-8382-298X")),
+ person("University of Illinois, NCSA", role = c("cph")))
 Description: The Predictive Ecosystem Carbon Analyzer (PEcAn) is a scientific
     workflow management tool that is designed to simplify the management of
     model parameterization, execution, and analysis. The PECAn.data.atmosphere
diff --git a/modules/data.atmosphere/NEWS.md b/modules/data.atmosphere/NEWS.md
index 13ca4a1b68..fcfc775bcf 100644
--- a/modules/data.atmosphere/NEWS.md
+++ b/modules/data.atmosphere/NEWS.md
@@ -3,6 +3,12 @@
 ## Fixed
 
 * `download.AmerifluxLBL` no longer wrongly re-fetches raw zipfiles when `overwrite = FALSE`
+* `download.NOAA_GEFS` is updated to work again with GEFS v12.3,
+	the current release as of this writing in July 2024 (#3349).
+
+## Changed
+* Removed `sitename` and `username` from the formal arguments of `download.NOAA_GEFS`.
+	Before they were silently ignored, now they're treated as part of `...` (which is also ignored!).
 
 # PEcAn.data.atmosphere 1.8.0
 
diff --git a/modules/data.atmosphere/R/GEFS_helper_functions.R b/modules/data.atmosphere/R/GEFS_helper_functions.R
index 754580ae0d..99d3783df4 100644
--- a/modules/data.atmosphere/R/GEFS_helper_functions.R
+++ b/modules/data.atmosphere/R/GEFS_helper_functions.R
@@ -17,21 +17,11 @@ noaa_grid_download <- function(lat_list, lon_list, forecast_time, forecast_date,
   
   
   download_grid <- function(ens_index, location, directory, hours_char, cycle, base_filename1, vars,working_directory){
-    #for(j in 1:31){
-    if(ens_index == 1){
-      base_filename2 <- paste0("gec00",".t",cycle,"z.pgrb2a.0p50.f")
-      curr_hours <- hours_char[hours <= 384]
-    }else{
-      if((ens_index-1) < 10){
-        ens_name <- paste0("0",ens_index - 1)
-      }else{
-        ens_name <- as.character(ens_index -1)
-      }
-      base_filename2 <- paste0("gep",ens_name,".t",cycle,"z.pgrb2a.0p50.f")
-      curr_hours <- hours_char
-    }
-    
-    
+    member_type <- if (ens_index == 1) { "gec" } else { "gep" } # "_c_ontrol", "_p_erturbed"
+    ens_idxname <- stringr::str_pad(ens_index - 1, width = 2, pad = "0")
+    base_filename2 <- paste0(member_type,ens_idxname,".t",cycle,"z.pgrb2a.0p50.f")
+    curr_hours <- hours_char
+
     for(i in 1:length(curr_hours)){
       file_name <- paste0(base_filename2, curr_hours[i])
       
@@ -73,37 +63,12 @@ noaa_grid_download <- function(lat_list, lon_list, forecast_time, forecast_date,
   
   model_dir <- file.path(output_directory, model_name_raw)
   
+  #Availability: most recent 4 days
   curr_time <- lubridate::with_tz(Sys.time(), tzone = "UTC")
   curr_date <- lubridate::as_date(curr_time)
-  
-  noaa_page <- readLines('https://nomads.ncep.noaa.gov/pub/data/nccf/com/gens/prod/')
-  
-  potential_dates <- NULL
-  for(i in 1:length(noaa_page)){
-    if(stringr::str_detect(noaa_page[i], ">gefs.")){
-      end <- stringr::str_locate(noaa_page[i], ">gefs.")[2]
-      dates <- stringr::str_sub(noaa_page[i], start = end+1, end = end+8)
-      potential_dates <- c(potential_dates, dates)
-    }
-  }
-  
-  
-  last_cycle_page <- readLines(paste0('https://nomads.ncep.noaa.gov/pub/data/nccf/com/gens/prod/gefs.', dplyr::last(potential_dates)))
-  
-  potential_cycle <- NULL
-  for(i in 1:length(last_cycle_page)){
-    if(stringr::str_detect(last_cycle_page[i], 'href=\"')){
-      end <- stringr::str_locate(last_cycle_page[i], 'href=\"')[2]
-      cycles <- stringr::str_sub(last_cycle_page[i], start = end+1, end = end+2)
-      if(cycles %in% c("00","06", "12", "18")){
-        potential_cycle <- c(potential_cycle, cycles)
-      }
-    }
-  }
-  
-  potential_dates <- lubridate::as_date(potential_dates)
-  
-  potential_dates = potential_dates[which(potential_dates == forecast_date)]
+  potential_dates <- curr_date - lubridate::days(3:0)
+
+  potential_dates <- potential_dates[which(potential_dates == forecast_date)]
   
   if(length(potential_dates) == 0){PEcAn.logger::logger.error("Forecast Date not available")}
   
@@ -118,7 +83,10 @@ noaa_grid_download <- function(lat_list, lon_list, forecast_time, forecast_date,
                      floor(min(lat_list)))
   
   base_filename1 <- "https://nomads.ncep.noaa.gov/cgi-bin/filter_gefs_atmos_0p50a.pl?file="
-  vars <- "&lev_10_m_above_ground=on&lev_2_m_above_ground=on&lev_surface=on&lev_entire_atmosphere=on&var_APCP=on&var_DLWRF=on&var_DSWRF=on&var_PRES=on&var_RH=on&var_TMP=on&var_UGRD=on&var_VGRD=on&var_TCDC=on"
+  vars <- paste0(
+    "&lev_10_m_above_ground=on&lev_2_m_above_ground=on&lev_surface=on&lev_entire_atmosphere=on",
+    "&var_APCP=on&var_DLWRF=on&var_DSWRF=on&var_PRES=on&var_RH=on&var_TMP=on",
+    "&var_UGRD=on&var_VGRD=on&var_TCDC=on")
   
   for(i in 1:length(potential_dates)){
     
@@ -143,11 +111,11 @@ noaa_grid_download <- function(lat_list, lon_list, forecast_time, forecast_date,
         print(paste("Downloading", forecast_date, cycle))
         
         if(cycle == "00"){
-          hours <- c(seq(0, 240, 3),seq(246, 384, 6))
-          hours <- hours[hours<=end_hr]
+          hours <- c(seq(0, 240, 3),seq(246, 840, 6))
         }else{
-          hours <- c(seq(0, 240, 3),seq(246, min(end_hr, 840) , 6))
+          hours <- c(seq(0, 240, 3),seq(246, 384 , 6))
         }
+        hours <- hours[hours<=end_hr]
         hours_char <- hours
         hours_char[which(hours < 100)] <- paste0("0",hours[which(hours < 100)])
         hours_char[which(hours < 10)] <- paste0("0",hours_char[which(hours < 10)])
@@ -163,12 +131,12 @@ noaa_grid_download <- function(lat_list, lon_list, forecast_time, forecast_date,
         
         parallel::mclapply(X = ens_index,
                            FUN = download_grid,
-                           location,
-                           directory,
-                           hours_char,
-                           cycle,
-                           base_filename1,
-                           vars,
+                           location = location,
+                           directory = directory,
+                           hours_char = hours_char,
+                           cycle = cycle,
+                           base_filename1 = base_filename1,
+                           vars = vars,
                            working_directory = model_date_hour_dir,
                            mc.cores = 1)
       }else{
@@ -177,6 +145,9 @@ noaa_grid_download <- function(lat_list, lon_list, forecast_time, forecast_date,
     }
   }
 }
+
+
+
 #' Extract and temporally downscale points from downloaded grid files
 #'
 #' @param lat_list lat for site
@@ -222,23 +193,13 @@ process_gridded_noaa_download <- function(lat_list,
     dlwrfsfc <- array(NA, dim = c(site_length, length(hours_char)))
     dswrfsfc <- array(NA, dim = c(site_length, length(hours_char)))
     
-    if(ens_index == 1){
-      base_filename2 <- paste0("gec00",".t",cycle,"z.pgrb2a.0p50.f")
-    }else{
-      if(ens_index-1 < 10){
-        ens_name <- paste0("0",ens_index-1)
-      }else{
-        ens_name <- as.character(ens_index-1)
-      }
-      base_filename2 <- paste0("gep",ens_name,".t",cycle,"z.pgrb2a.0p50.f")
-    }
+    member_type <- if (ens_index == 1) { "gec" } else { "gep" } # "_c_ontrol", "_p_erturbed"
+    ens_idxname <- stringr::str_pad(ens_index - 1, width = 2, pad = "0")
+    base_filename2 <- paste0(member_type,ens_idxname,".t",cycle,"z.pgrb2a.0p50.f")
     
     lats <- round(lat_list/.5)*.5
     lons <- round(lon_list/.5)*.5
     
-    if(lons < 0){
-      lons <- 360 + lons
-    }
     curr_hours <- hours_char
     
     for(hr in 1:length(curr_hours)){
@@ -263,8 +224,13 @@ process_gridded_noaa_download <- function(lat_list,
           vgrd10m[s, hr]  <- grib_data_df$`10[m] HTGL=Specified height level above ground; v-component of wind [m/s]`[index]
           
           if(curr_hours[hr] != "000"){
-            apcpsfc[s, hr]  <- grib_data_df$`SFC=Ground or water surface; 03 hr Total precipitation [kg/(m^2)]`[index]
-            tcdcclm[s, hr]  <- grib_data_df$`RESERVED(10) (Reserved); Total cloud cover [%]`[index]
+            # total precip alternates being named as 3 or 6 hr total
+            # TODO: not sure if the contents actually differ or if this is a labeling bug in the grib files
+            precip_hr <- if ((as.numeric(curr_hours[hr]) %% 2) == 1) { "03" } else { "06" }
+            precip_name <- paste("SFC=Ground or water surface;", precip_hr, "hr Total precipitation [kg/(m^2)]")
+            apcpsfc[s, hr]  <- grib_data_df[[precip_name]][index]
+
+            tcdcclm[s, hr]  <- grib_data_df$`EATM=Entire Atmosphere; Total cloud cover [%]`[index]
             dswrfsfc[s, hr] <- grib_data_df$`SFC=Ground or water surface; Downward Short-Wave Rad. Flux [W/(m^2)]`[index]
             dlwrfsfc[s, hr] <- grib_data_df$`SFC=Ground or water surface; Downward Long-Wave Rad. Flux [W/(m^2)]`[index]
           }
@@ -301,17 +267,15 @@ process_gridded_noaa_download <- function(lat_list,
   
   
   
-  cycle <-forecast_time
+  cycle <- forecast_time
   curr_forecast_time <- forecast_date + lubridate::hours(cycle)
-  if(cycle < 10) cycle <- paste0("0",cycle)
-  if(cycle == "00"){
-    hours <- c(seq(0, 240, 3),seq(246, 840 , 6))
-  }else{
-    hours <- c(seq(0, 240, 3),seq(246, 384 , 6))
+  cycle <- stringr::str_pad(cycle, width = 2, pad = "0")
+  if (cycle == "00") {
+    hours <- c(seq(0, 240, 3),seq(246, 840, 6))
+  } else {
+    hours <- c(seq(0, 240, 3),seq(246, 384, 6))
   }
-  hours_char <- hours
-  hours_char[which(hours < 100)] <- paste0("0",hours[which(hours < 100)])
-  hours_char[which(hours < 10)] <- paste0("0",hours_char[which(hours < 10)])
+  hours_char <- stringr::str_pad(hours, width = 3, pad = "0") # 3->"003", 384->"384"
   
   raw_files <- list.files(file.path(model_name_raw_dir,forecast_date,cycle))
   hours_present <- as.numeric(stringr::str_sub(raw_files, start = 25, end = 27))
@@ -341,19 +305,21 @@ process_gridded_noaa_download <- function(lat_list,
                                  FUN = extract_sites,
                                  hours_char = hours_char,
                                  hours = hours,
-                                 cycle,
-                                 site_id,
-                                 lat_list,
-                                 lon_list,
+                                 cycle = cycle,
+                                 site_id = site_id,
+                                 lat_list = lat_list,
+                                 lon_list = lon_list,
                                  working_directory = file.path(model_name_raw_dir,forecast_date,cycle),
                                  mc.cores = 1)
     
     
-    forecast_times <- lubridate::as_datetime(forecast_date) + lubridate::hours(as.numeric(cycle)) + lubridate::hours(as.numeric(hours_char))
+    forecast_times <- lubridate::as_datetime(forecast_date) +
+      lubridate::hours(as.numeric(cycle)) +
+      lubridate::hours(as.numeric(hours_char))
     
     
     
-    #Convert negetive longitudes to degrees east
+    #Convert negative longitudes to degrees east
     if(lon_list < 0){
       lon_east <- 360 + lon_list
     }else{
@@ -425,17 +391,18 @@ process_gridded_noaa_download <- function(lat_list,
     #Calculate wind speed from east and north components
     wind_speed <- sqrt(noaa_data$eastward_wind$value^2 + noaa_data$northward_wind$value^2)
     
-    forecast_noaa <- tibble::tibble(time = noaa_data$air_temperature$forecast.date,
-                                    NOAA.member = noaa_data$air_temperature$ensembles,
-                                    air_temperature = noaa_data$air_temperature$value,
-                                    air_pressure= noaa_data$air_pressure$value,
-                                    relative_humidity = noaa_data$relative_humidity$value,
-                                    surface_downwelling_longwave_flux_in_air = noaa_data$surface_downwelling_longwave_flux_in_air$value,
-                                    surface_downwelling_shortwave_flux_in_air = noaa_data$surface_downwelling_shortwave_flux_in_air$value,
-                                    precipitation_flux = noaa_data$precipitation_flux$value,
-                                    specific_humidity = specific_humidity,
-                                    cloud_area_fraction = noaa_data$cloud_area_fraction$value,
-                                    wind_speed = wind_speed)
+    forecast_noaa <- tibble::tibble(
+      time = noaa_data$air_temperature$forecast.date,
+      NOAA.member = noaa_data$air_temperature$ensembles,
+      air_temperature = noaa_data$air_temperature$value,
+      air_pressure= noaa_data$air_pressure$value,
+      relative_humidity = noaa_data$relative_humidity$value,
+      surface_downwelling_longwave_flux_in_air = noaa_data$surface_downwelling_longwave_flux_in_air$value,
+      surface_downwelling_shortwave_flux_in_air = noaa_data$surface_downwelling_shortwave_flux_in_air$value,
+      precipitation_flux = noaa_data$precipitation_flux$value,
+      specific_humidity = specific_humidity,
+      cloud_area_fraction = noaa_data$cloud_area_fraction$value,
+      wind_speed = wind_speed)
     
     forecast_noaa$cloud_area_fraction <- forecast_noaa$cloud_area_fraction / 100 #Convert from % to proportion
     
@@ -455,14 +422,10 @@ process_gridded_noaa_download <- function(lat_list,
     for (ens in 1:31) { # i is the ensemble number
       
       #Turn the ensemble number into a string
-      if(ens-1< 10){
-        ens_name <- paste0("0",ens-1)
-      }else{
-        ens_name <- ens - 1
-      }
+      ens_name <- stringr::str_pad(ens - 1, width = 2, pad = "0")
       
       forecast_noaa_ens <- forecast_noaa %>%
-        dplyr::filter(NOAA.member == ens) %>%
+        dplyr::filter(.data$NOAA.member == ens) %>%
         dplyr::filter(!is.na(.data$air_temperature))
       
       end_date <- forecast_noaa_ens %>%
@@ -525,6 +488,15 @@ process_gridded_noaa_download <- function(lat_list,
   return(results_list)
 } #process_gridded_noaa_download
 
+
+
+
+
+
+
+
+
+
 #' @title Downscale NOAA GEFS from 6hr to 1hr
 #' @return None
 #'
@@ -645,6 +617,14 @@ temporal_downscale <- function(input_file, output_file, overwrite = TRUE, hr = 1
 
 
 
+
+
+
+
+
+
+
+
 ##' @title Write NOAA GEFS netCDF
 ##' @name write_noaa_gefs_netcdf
 ##' @param df data frame of meterological variables to be written to netcdf.  Columns
@@ -711,4 +691,4 @@ write_noaa_gefs_netcdf <- function(df, ens = NA, lat, lon, cf_units, output_file
     
     ncdf4::nc_close(nc_flptr)  #Write to the disk/storage
   }
-}
\ No newline at end of file
+}
diff --git a/modules/data.atmosphere/R/download.NOAA_GEFS.R b/modules/data.atmosphere/R/download.NOAA_GEFS.R
index e68bc7d166..f8f9631ae6 100644
--- a/modules/data.atmosphere/R/download.NOAA_GEFS.R
+++ b/modules/data.atmosphere/R/download.NOAA_GEFS.R
@@ -6,36 +6,43 @@
 ##' @references https://www.ncdc.noaa.gov/crn/measurements.html
 ##' 
 ##' @section NOAA_GEFS General Information:
-##' This function downloads NOAA GEFS weather data.  GEFS is an ensemble of 21 different weather forecast models.  
-##' A 16 day forecast is avaliable every 6 hours.  Each forecast includes information on a total of 8 variables.  
-##' These are transformed from the NOAA standard to the internal PEcAn
-##' standard.
-##' 
-##' @section Data Avaliability:
-##' NOAA GEFS weather data is avaliable on a rolling 12 day basis; dates provided in "start_date" must be within this range. The end date can be any point after
-##' that, but if the end date is beyond 16 days, only 16 days worth of forecast are recorded.  Times are rounded down to the previous 6 hour forecast.  NOAA
-##' GEFS weather data isn't always posted immediately, and to compensate, this function adjusts requests made in the last two hours
-##' back two hours (approximately the amount of time it takes to post the data) to make sure the most current forecast is used.
+##' This function downloads NOAA GEFS weather data.  GEFS is an ensemble of 31 different weather forecast models.
+##' A 16 day forecast is available every 6 hours and a 35 day forecast is available every 24 hours.
+##' Both are at 3-hour frequency for the first 10 days of the forecast and 6-hour frequency beyond that.
+##' Each forecast includes information on a total of 8 variables.
+##' These are transformed from the NOAA standard to the internal PEcAn standard.
 ##' 
+##' @section Data Availability:
+##' NOAA GEFS weather data is available on a rolling 4 day basis.
+##' Dates provided in "start_date" must be within this range.
+##' The end date can be any point after that, but if the end date is beyond 16 days
+##' (35 days for the midnight UTC forecast), only 16 (35) days worth of forecast are retrieved.
+##' Times are rounded down to the previous 6 hour forecast.
+##'
+##' NOAA GEFS weather data isn't always posted immediately. Each 16-day forecast takes
+##' approximately three hours to run, and the once-a-day forecasts for days 17-35 are
+##' posted much later (up to 21 hours) than the forecasts for days 0 to 16.
+##' See the [GEFS v12 release announcement](https://www.weather.gov/media/notification/pdf2/scn20-75gefs_v12_changes.pdf)
+##' for details.
+##'
 ##' @section Data Save Format:
-##' Data is saved in the netcdf format to the specified directory.  File names reflect the precision of the data to the given range of days.
+##' Data is saved in the netcdf format to the specified directory.
+##'   File names reflect the precision of the data to the given range of days.
 ##' NOAA.GEFS.willow creek.3.2018-06-08T06:00.2018-06-24T06:00.nc specifies the forecast, using ensemble number 3 at willow creek on
 ##' June 6th, 2018 at 6:00 a.m. to June 24th, 2018 at 6:00 a.m.
 ##' 
 ##' @return A list of data frames is returned containing information about the data file that can be used to locate it later.  Each
 ##' data frame contains information about one file.
 ##'
-##' @param outfolder Directory where results should be written
-##' @param start_date, Range of dates/times to be downloaded (default assumed to be time that function is run) 
-##' @param end_date, end date for range of dates to be downloaded (default 16 days from start_date)
+##' @param site_id The unique ID given to each site. This is used as part of the file name.
 ##' @param lat.in site latitude in decimal degrees
 ##' @param lon.in site longitude in decimal degrees
-##' @param site_id The unique ID given to each site. This is used as part of the file name.
-##' @param sitename Site name 
-##' @param username username from pecan workflow 
+##' @param outfolder Directory where results should be written
+##' @param start_date Range of dates/times to be downloaded (default assumed to be time that function is run) 
+##' @param end_date end date for range of dates to be downloaded (default 16 days from start_date)
+##' @param downscale logical, assumed True. Indicates whether data should be downscaled to hourly
 ##' @param overwrite logical. Download a fresh version even if a local file with the same name already exists?
-##' @param downscale logical, assumed True. Indicated whether data should be downscaled to hourly
-##' @param ...  Additional optional parameters
+##' @param ...  Additional optional parameters, currently ignored
 ##'
 ##' @export
 ##' 
@@ -50,8 +57,6 @@
 ##' @author Quinn Thomas, modified by K Zarada 
 ##' 
 download.NOAA_GEFS <- function(site_id,
-                               sitename = NULL,
-                               username = 'pecan',
                                lat.in,
                                lon.in,
                                outfolder,
diff --git a/modules/data.atmosphere/R/half_hour_downscale.R b/modules/data.atmosphere/R/half_hour_downscale.R
index bb14748412..9b2efbb08b 100644
--- a/modules/data.atmosphere/R/half_hour_downscale.R
+++ b/modules/data.atmosphere/R/half_hour_downscale.R
@@ -223,8 +223,16 @@ downscale_ShortWave_to_half_hrly <- function(df,lat, lon, hr = 0.5){
   
   for (k in 1:nrow(data.hrly)) {
     if(is.na(data.hrly$surface_downwelling_shortwave_flux_in_air[k])){
-      SWflux <- as.matrix(subset(df, .data$day == data.hrly$day[k] & .data$hour == data.hrly$hour[k], data.hrly$surface_downwelling_shortwave_flux_in_air[k]))
-      data.hrly$surface_downwelling_shortwave_flux_in_air[k] <- ifelse(data.hrly$rpotHM[k] > 0, as.numeric(SWflux[1])*(data.hrly$rpotH[k]/data.hrly$rpotHM[k]),0)
+      SWflux <- as.matrix(
+        df$surface_downwelling_shortwave_flux_in_air[
+          df$day == data.hrly$day[k] & df$hour == data.hrly$hour[k]
+        ]
+      )
+      data.hrly$surface_downwelling_shortwave_flux_in_air[k] <- ifelse(
+        data.hrly$rpotHM[k] > 0,
+        as.numeric(SWflux[1]) * (data.hrly$rpotH[k] / data.hrly$rpotHM[k]),
+        0
+      )
     }
   }
   
@@ -287,8 +295,6 @@ downscale_repeat_6hr_to_half_hrly <- function(df, varName, hr = 0.5){
   for(k in 1:dim(df)[1]){
     if (is.na(df$lead_var[k])) {
       df$lead_var[k] <- df$lead_var[k-1]
-    }else{
-      df$lead_var[k] <- df$lead_var[k]
     }
   }
   
diff --git a/modules/data.atmosphere/man/download.NOAA_GEFS.Rd b/modules/data.atmosphere/man/download.NOAA_GEFS.Rd
index 05aa332be4..47dd834cc5 100644
--- a/modules/data.atmosphere/man/download.NOAA_GEFS.Rd
+++ b/modules/data.atmosphere/man/download.NOAA_GEFS.Rd
@@ -6,8 +6,6 @@
 \usage{
 download.NOAA_GEFS(
   site_id,
-  sitename = NULL,
-  username = "pecan",
   lat.in,
   lon.in,
   outfolder,
@@ -21,25 +19,21 @@ download.NOAA_GEFS(
 \arguments{
 \item{site_id}{The unique ID given to each site. This is used as part of the file name.}
 
-\item{sitename}{Site name}
-
-\item{username}{username from pecan workflow}
-
 \item{lat.in}{site latitude in decimal degrees}
 
 \item{lon.in}{site longitude in decimal degrees}
 
 \item{outfolder}{Directory where results should be written}
 
-\item{start_date, }{Range of dates/times to be downloaded (default assumed to be time that function is run)}
+\item{start_date}{Range of dates/times to be downloaded (default assumed to be time that function is run)}
 
-\item{end_date, }{end date for range of dates to be downloaded (default 16 days from start_date)}
+\item{end_date}{end date for range of dates to be downloaded (default 16 days from start_date)}
 
-\item{downscale}{logical, assumed True. Indicated whether data should be downscaled to hourly}
+\item{downscale}{logical, assumed True. Indicates whether data should be downscaled to hourly}
 
 \item{overwrite}{logical. Download a fresh version even if a local file with the same name already exists?}
 
-\item{...}{Additional optional parameters}
+\item{...}{Additional optional parameters, currently ignored}
 }
 \value{
 A list of data frames is returned containing information about the data file that can be used to locate it later.  Each
@@ -56,23 +50,32 @@ but is converted at the station and downloaded in Kelvin.
 
 \section{NOAA_GEFS General Information}{
 
-This function downloads NOAA GEFS weather data.  GEFS is an ensemble of 21 different weather forecast models.  
-A 16 day forecast is avaliable every 6 hours.  Each forecast includes information on a total of 8 variables.  
-These are transformed from the NOAA standard to the internal PEcAn
-standard.
+This function downloads NOAA GEFS weather data.  GEFS is an ensemble of 31 different weather forecast models.
+A 16 day forecast is available every 6 hours and a 35 day forecast is available every 24 hours.
+Both are at 3-hour frequency for the first 10 days of the forecast and 6-hour frequency beyond that.
+Each forecast includes information on a total of 8 variables.
+These are transformed from the NOAA standard to the internal PEcAn standard.
 }
 
-\section{Data Avaliability}{
+\section{Data Availability}{
+
+NOAA GEFS weather data is available on a rolling 4 day basis.
+Dates provided in "start_date" must be within this range.
+The end date can be any point after that, but if the end date is beyond 16 days
+(35 days for the midnight UTC forecast), only 16 (35) days worth of forecast are retrieved.
+Times are rounded down to the previous 6 hour forecast.
 
-NOAA GEFS weather data is avaliable on a rolling 12 day basis; dates provided in "start_date" must be within this range. The end date can be any point after
-that, but if the end date is beyond 16 days, only 16 days worth of forecast are recorded.  Times are rounded down to the previous 6 hour forecast.  NOAA
-GEFS weather data isn't always posted immediately, and to compensate, this function adjusts requests made in the last two hours
-back two hours (approximately the amount of time it takes to post the data) to make sure the most current forecast is used.
+NOAA GEFS weather data isn't always posted immediately. Each 16-day forecast takes
+approximately three hours to run, and the once-a-day forecasts for days 17-35 are
+posted much later (up to 21 hours) than the forecasts for days 0 to 16.
+See the [GEFS v12 release announcement](https://www.weather.gov/media/notification/pdf2/scn20-75gefs_v12_changes.pdf)
+for details.
 }
 
 \section{Data Save Format}{
 
-Data is saved in the netcdf format to the specified directory.  File names reflect the precision of the data to the given range of days.
+Data is saved in the netcdf format to the specified directory.
+  File names reflect the precision of the data to the given range of days.
 NOAA.GEFS.willow creek.3.2018-06-08T06:00.2018-06-24T06:00.nc specifies the forecast, using ensemble number 3 at willow creek on
 June 6th, 2018 at 6:00 a.m. to June 24th, 2018 at 6:00 a.m.
 }