CASM Update and Snow Data Products - May 2023
CASM Stakeholders
While the snowmelt season is in full swing, there is still a huge amount of high-elevation snow across the state. ASO, Inc., M3 Works, and NCAR are publishing regular datasets and reports on snow depth, snow water equivalent, and streamflow forecasts.
Below are some of the detailed data from this record-setting snow year. As a reminder, all data can be downloaded by accessing the ASO, Inc. data portal here (requires a free account): https://data.airbornesnowobservatories.com/
You can also explore the measured snow depths from ASO flights and related SWE data:
WRF Hydro
NCAR has developed an initial set of streamflow forecasts using its WRF-Hydro model that ingests ASO data to inform and improve those forecasts. In the report below, the seasonal water supply forecast values presented are the median (Q50) forecasts for April-July. The Dolores, Rio Grande, and Conejos basins also have Apr-Sep forecast values provided. We are working on processes to provide the full set (90%, 75%, 50%, 25%, 10%) of exceedance probability forecasted flow values in a tabular format for future reports and hope to have that available soon.
WRF-Hydro runs and reports are now being released on a weekly cadence:
5/22/2023 WRF-Hydro ASO-Informed Streamflow Forecast (PDF)
5/11/2023 WRF-Hydro ASO-Informed Streamflow Forecast (PDF)
M3Works iSnobal Model Results
In addition to WRF-Hydro, M3 Works is publishing regular updates to their physically based iSnobal snowpack model. Once the first ASO snow survey of the season is available, the iSnobal model tracks the snowpack quite closely. This document contains a detailed description of how iSnobal integrates ASO data and models snowpack conditions.
This week M3 Works produced another round of ASO-informed snowpack reports for all basins that were the subject of airborne snow surveys this year. These reports show the modeled snowpack within each major ASO basin with the last updated date is shown. All of these reports include the ingestion of ASO snow depth data and snow density analysis to inform and correct the model results. Reports are all downloadable here:
Upper Colorado: Blue River (5/16), Roaring Fork River and Fryingpan Headwaters (5/16), Windy Gap/Fraser (5/16)
South Platte: Clear Creek (5/16), Boulder Creek (5/16), Big Thompson (5/21), Little Thompson (5/21), St. Vrain Creek (5/21), Poudre River (5/22)
Gunnison: East River (5/23), Taylor River (5/23), Lottis Creek (5/23)
Southwest: Dolores River (5/25)
Rio Grande: Conejos River (5/16)
Summary of ASO activities in CASM Basins for 2023
Dillon Reservoir (Blue River)
4/16/2023 Survey - Completed, data available on ASO data portal
5/29/2023 - Snow survey flight completed; data processing now
Colorado River at Windy Gap and Fraser River
4/16/2023 Survey - Completed, data available on ASO data portal
5/27/2023 Survey - Snow survey flight completed, data processing now
East and Taylor Rivers
4/1/2023 Survey - Completed, data available on ASO data portal
5/23/2023 Survey - Completed, data available on ASO data portal
Dolores River
4/6/2023 Survey - Completed, data available on ASO data portal
5/25/2023 Survey - Completed, data available on ASO data portal
Conejos River
5/5/2023 Survey - Completed, data available on ASO data portal
Front Range, Clear Creek through Poudre River
5/9, 21-22/2023 Survey - Completed, data available on ASO data portal
Early June Survey - Waiting for more snowmelt before flying
South Platte Above 285
4/16/2023 Survey - Completed, data available on ASO data portal
5/26/2023 Survey - Snow survey flight completed, data processing now
Roaring Fork River
4/11-12/2023 Survey - Completed, data available on ASO data portal
5/28/2023 Survey - Snow survey flight completed, data processing now
Thanks
CASM Team
