Forecast for Hoosier Legally and Physically Available Yield

Summary

Details

1. Forecast Yield for 2024 is 9,600 acre-feet, which is 74.5% of average actual yield (12,892) from 1988-2022

This forecast was made on March 24, 2024
Data sources:

• from WEAP model Favorite called "Hoosier L&P Actual and Forecast Yield"


2. Forecasts made this year by SEI and WEAP (download CSV)



Forecast Date	Forecast
2/4/2024	8,965 AF
2/11/2024	9,187 AF
2/18/2024	9,121 AF
2/25/2024	8,757 AF
3/3/2024	9,641 AF
3/10/2024	9,939 AF
3/17/2024	9,863 AF
3/24/2024	9,600 AF



3. Unconstrained Yields prior to 2024, with current forecast

(CSV)

Data sources:

• Historical Unconstrained Yields for 1988-2022 from: BlueYields.xlsx:'Unconstrained Yield'!A4:B37


4. Snow Water Equivalent (SWE)

Observed Hoosier SWE on March 24, 2024: 16.3 inches, which is 118% of March 24 average SWE (13.8 in) from 1981-2022

Modeled and forecasted SWE ("Snow Depth (MWE)") compared to Hoosier SNOTEL site ("Snow Gauge")

(CSV)


(CSV) (CSV)
Data sources:

• Historical SWE from SNOTEL website (SNOTEL Site 531: Hoosier Pass, CO)
• Modeled/forecasted SWE
From WEAP model favorite: "Snow Accumulation vs. Gauge Hoosier 3000 to 3500")


5. Streamflow at Shoshone

(CSV)
Data sources:

• from WEAP model favorite: "Shoshone Gauge Comparison"



6. Streamflow near Cameo

(CSV)
Data sources:

• from WEAP model favorite: "Cameo Gauge Comparison"



7. Precipitation for the Water Year (Oct 1 to Sep 30)

(CSV) (CSV)
Data sources:

• from WEAP model favorite: "Precipitation Upper Blue"



8. Cumulative WY-to-date precipitation (Oct 1 to Mar 24)

Cumulative precipitation from Current Water Year start (Oct 1) to date of forecast (Mar 24); also compared to historical years
(CSV) (CSV)
Data sources:

• from WEAP model favorite: "Precipitation Upper Blue", summed over weeks from Oct 1 to Mar 24



9. Cumulative precipitation from forecast date to end of WY (Mar 24 to Sep 30)

(CSV) (CSV)
Data sources:

• from WEAP model favorite: "Precipitation Upper Blue", summed over weeks from Mar 24 to Sep 30

Methods

1. Use of GridMET climate products
Climate data from GridMET: https://www.climatologylab.org/gridmet.html

Direct download and processing into WEAP of:
• Historical daily climate (1979 through 2023)
• Year to date daily climate (Jan 1, 2024 through yesterday)
• Seasonal daily forecast: Available first of each month for 7 months ahead


2. How the climate datasets are assembled



3. How the WEAP model is run
• Forecast to be made on Feb 8 (let's say)
• Use the WEAP interface to update climate datasets, both year to date and seasonal forecast
• Run the model for WY 1980 through WY 2025
• Extract results for Hoosier L&P
• Sum the results from Apr 1 through Nov 30, 2024

WEAP Model

References and Links

1. Previous Hoosier L&P Forecasts: http://csu.weap21.org/Forecast
2. Forecast streamflows by USDA Natural Resources Conservation Service (NRCS)
• Colorado Forecast Streamflow Point Map
• How NRCS forecasts are made
3. Snowpack Map
4. Gridmet Seasonal Forecast Maps
5. Observed SWE from SNOTEL site 531