| GLFFC Run Times
Daily 18 UTC Grid Update
The daily 18 UTC grid update is run at 18:30 UTC for the given day. This time is used to ensure all gridded products are available for proper analysis of the 18 UTC observations. Grids change at 18:30 UTC as well on the Maps overlays. A browser refresh may be required to see these changes depending on the features used. It is possible for the observations to be out of sync with the grid map overlays. In fact, most values will differ because the gridded products used for the final observation for the day at 18 UTC are reanalysis products and do not always reflect the exact observed values for each station. This is a known limitation of gridded products.
Grid 1 and 2 Day Forecast Updates
The 1 and 2 day grid forecasts are run 4 times a day for the target hours of 03 UTC, 09 UTC, 15 UTC, 21 UTC. The below table shows when each is run:
* 03 UTC model run for 18 UTC day 1 and day 2 forecasts: Run at 03:57 UTC
* 09 UTC model run for 18 UTC day 1 and day 2 forecasts: Run at 09:57 UTC
* 15 UTC model run for 18 UTC day 1 and day 2 forecasts: Run at 15:57 UTC for the next 2 days (not including current day)
* 21 UTC model run for 18 UTC day 1 and day 2 forecasts: Run at 21:57 UTC for the next 2 days (not including current day)
All map dates, station updates, and model grid updates are sensitive to the model runs and the final station observation runs for the final 18 UTC observation for the day. It takes several minutes for all observations and gridded data products to become available, so there are latencies of 30 to 90 minutes after 18 UTC for the final values to complete.
Station Observations and Forecasts
18 UTC CFFDRS - Daily, OBS on DAY0: 18:30 UTC DAY0, 19:30 UTC DAY0, 20:30 UTC DAY0, 0:30 UTC DAY1, 4:30 UTC DAY1
CFFDRS - Hourly, OBS run at :16 every hour (that is a bit odd, because 18:16-18:30 there could be an hourly value, but not the daily value.)
* 18 UTC CFFDRS - Daily, FCST on DAY1 without observed precip using 15 UTC DAY0 model run: 18:30 UTC DAY0, 19:30 UTC DAY0, 20:30 UTC DAY0
* 18 UTC CFFDRS - Daily, FCST on DAY1 with 6 hrs observed precip using 21 UTC DAY0 model run: 0:32 UTC DAY1, 1:32 UTC DAY1, 2:32 UTC DAY1
* 18 UTC CFFDRS - Daily, FCST on DAY1 with 12 hrs observed precip using 03 UTC DAY1 model run: 6:32 UTC DAY1, 7:32 UTC DAY1
(the 3rd run was removed here because it was always hanging)
* 18 UTC CFFDRS - Daily, FCST on DAY1 with 18 hrs observed precip using 09 UTC DAY1 model run: 12:32 UTC DAY1, 13:32 UTC DAY1, 14:32 UTC DAY1
18 UTC CFFDRS - Daily, FCST on DAY2 at same times as for FCST on DAY1. FCST on DAY1 must be available.