National Weather Service. Harold H. Opitz Hydrologist in Charge

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1 National Weather Service Harold H. Opitz Hydrologist in Charge

2 Goals Organization Role of the River Forecast Center Describe Forecast System & Tools Other Details

3 NWS River Forecast Centers Northwest River Forecast Center 13 NWS River Forecast Centers

Responsibility 2 Canadian Provinces Elevation Range: 10-14110 ft msl 3 4300 m msl Variable

4 Northwest River Forecast Center: Geography/Topography Forecast Responsibilities for the Columbia River Basin & Tributaries 326,225 mi 2 (844,922 km 2 ) 6-state Area of Responsibility 2 Canadian Provinces Elevation Range: ft msl m msl Variable Orographic Relief Highly Variable Precip/Snow Seasonal Operational Workload Economies driven by Water Supply

5 Columbia River Power System 15 th longest river in North America 6 th largest volume of Runoff 137 million acre-feet annually 1.69x10 11 m 3 82 major federal reservoirs Numerous privately owned projects

Northwest River Forecast Center: Regulation Projects Operated for flood control, navigation, irrigation, municipal and industrial water supply, recreation, fish and wildlife and

6 Northwest River Forecast Center: Regulation Projects Operated for flood control, navigation, irrigation, municipal and industrial water supply, recreation, fish and wildlife and power production Market Power from 31 Federal Dams (21 COE, 10 BOR) 80% of power marketed by BPA is hydropower Canada only 18% of basin in size, but accounts for 37% of annual runoff

7 Forecast Regulation Interagency Collaboration and Coordination Manage Water Resources Power Biological Species Management Water Quality Projections Render Outflow Projections

8 Northwest River Forecast Center: Activities Continuous data assimilation, modeling, and forecast preparation. Technical support to and interaction with WFOs and other Federal users. Technical support to and interaction with outside water management agencies and users. Operational procedure development.

9 River Forecast Centers: Services Mission Flood NWSForecasts Project Inflow Forecasts Recreational Forecasts Commerce & Navigation Water Supply Volumetric & Peak Flow Forecasts Drought Bulletins Statistical and Probabilistic Products

10 River Forecast Centers: Services Water Supply Program Official Volumetric Forecasts Used by decision agencies managing Columbia Basin Water resources International Treaty Obligations (Canada) RFC considered unbiased Forecast

Northwest River Forecast Center: Key Partnerships & Customers WFOs

Re-Calibration Project NRCS Water Supply Collaboration USGS

Forecast/Gaging Gage Support NMFS ESA/fish/Water Supply Bureau Of

11 Northwest River Forecast Center: Key Partnerships & Customers WFOs COE BPA Outreach Forecasts Regulation ESP and STP services Re-Calibration Project NRCS Water Supply Collaboration USGS Gaging/Rating Tables Port of Portland NOS Navigation Forecast/Gaging Gage Support NMFS ESA/fish/Water Supply Bureau Of Reclamation Regulation BCHydro (Canada) Treaty/Water Supply NCEP/HPC QPS Services Verification

12 Elevation Relief of Projects Snow very important (about 75% of our runoff) Typing precipitation is critical Feet above Sea Level 4,000ft 3,500ft 3,000ft 2,500ft 2,000ft 1,500ft 1,000ft 500ft Sea Level OCEAN United States Canada Treaty and Columbia River Base System Projects The Dalles Chief Joseph Grand Coulee Wells Chelan Rocky Reach Wanapum Rock Island McNary Priest Rapids Columbia River Treaty Project Dam in Canada Base System Federal Project Base System Non-Federal Project NOTE: FOR ILLUSTRATIVE PURPOSES; NOT ALL PROJECTS ARE SHOWN John Day Bonneville Arrow Lakes Mica Duncan Lake Kootenay Lake River Kootenay Thompson Falls Noxon Rapids Cabinet Gorge Albeni Falls Libby Box Canyon Pend Orielle River Miles from River Mouth Hungry Horse Clark Fork River Kerr Ice Harbor Spokane River So. Fork Flathead River Flathead River Coeur d Alene Lake Brownlee Oxbow Snake River

14 RFC Operations Modeling & Services Flow Short Term 10-Day Med Term >10Day <3 Month Long Term > 3 Month Time

15 Balancing Timeliness and Accuracy Forecast Value Timeliness Accuracy Forecast Lead Time

17 What is NWSRFS? National Weather Service River Forecast System A collection of interrelated software and data repositories capable of performing a wide variety of hydrologic/hydraulic models or operations Composed of 4 major functional systems that use the same hydrologic/hydraulic models or operations

18 NWSRFS Functional Structure Calibration Calibration System System Ensemble Streamflow Prediction Historical Data Historical Data Analysis Areal Time Series Model Calibration Parameters Hydrologic/ Hydraulic Models flow window now time Real-time Data Observed & Projected Hydromet Analysis Observed & Predicted Values Operational System Hydrologic/Hydraulic Models Short Term Forecast Current States Deterministic Products Verification Software Verification Data/Graphics Probabalistic Products Archived Data Observed and Forecast Verification System

19 Two of the Most Widely Used Models by Most RFCs SNOW-17 Model Simple Inputs Precipitation/Temperature Requires Calibration Sacramento Soil Moisture Accounting Model (SACSMA) Conceptual Model Requires Calibration

21 Operational River Forecast Process

22 Forecasting: What goes into the forecast? Flow Soil Moisture Precip/Temp Temperature Precipitation Present Conditions Future Conditions

23 Precipitation Data Quality Control Precipitation Interactive Process 6/24 hour data Climatological normalization Threshold comparisons Spatial comparisons Systematic estimation Manual forcing and over-rides rides Output qualified for model use

Air Temperature Data Quality Control Data analysis for 24-hour observed period Pre-defined station networks with similar domains Lapse to mean observational elevation.

24 Air Temperature Data Quality Control Data analysis for 24-hour observed period Pre-defined station networks with similar domains Lapse to mean observational elevation. Compute mean and standard deviation. Identify and estimate outliers and missing observations. Post validated observations and estimates for outliers and missing observations.

25 River and Reservoir Data (RRS) Observed Forecast Quality controlled in the context of simulated streamflow. Automated quality control is limited Bad Data

26 Forecast Forcings Precipitation & Temperature Grids Precipitation 10 days - 6 hr steps 10-days forcings 6-hour time step 2.5 km 604x644= grid cells Temp(mx) 10.5 days - 6 hr steps Point data Precip Temp (max/min) Freeze Levels Mean Areal Precip (phase 2) Mean Areal Temp (phase 2)

27 Precipitation Forecasts Points Grids MAPs Climatological Normalization and Distance Weighting Integration within Basin Boundaries

28 Forecasting Improvements Improvements in River Forecasting Require Improvements In the Meteorological Inputs

30 Hydrologic Operations River Forecasting

31 Models are not Perfect! Forecaster Experience Is Important Pattern recognition - historical case studies Gain familiarity with topography and gage network Hydrologist needs to Understand the Model

32 Processing Interactive Forecast Program (IFP) Forecast Groups Segments

33 Processing Interactive Forecast Display Rain + Melt Effective runoff Observed/Simulated Forecast Simulation

34 Forecasting & Regulation Collaboration and Coordination Headwater Reservoir Inflow 3-Components Inflow Storage Outflow Projected outflow Headwater Routing Reaches Local Watershed

35 Forecasting & Regulation: Collaboration and Coordination Projected Outflow Observed & Simulated Inflow Forecast Inflow

36 Forecasting & Regulation: Collaboration and Coordination

37 Run-time Modifications Interaction between the Forecaster and Model is needed because: Models used to simulate water movements are not perfect Calibration parameters are not perfect Rainfall, streamflow, and other input data are not perfect

38 Soil Moisture Accounting Example of Soil Moisture In Each Tank RUNOFF INTERFLOW BASEFLOW Generalized Sacramento Soil Moisture Accounting Model

39 Snow Modeling Observations & Model States Snow Water Equivalent Snow Ripeness Areal Extent of Cover

40 Runtime Modifications Adjusting the Model in Real-Time

41 Run Time Modifications to the Snow Model (2) Hydrologist Made a Run-Time modification to the Snow Model and Increased the snow Melt Correction Factor Observed and Simulated (1) Not Tracking (3) Result: Observed and Simulated is now on track

NWSRFS ESP - Ensemble Streamflow Prediction Calibration Calibration System System Ensemble Streamflow Prediction Historical Data Historical Data Analysis Areal Time Series Model Calibration

43 NWSRFS ESP - Ensemble Streamflow Prediction Calibration Calibration System System Ensemble Streamflow Prediction Historical Data Historical Data Analysis Areal Time Series Model Calibration Parameters Hydrologic/ Hydraulic Models flow window now time Real-time Data Observed & Projected Hydromet Analysis Observed & Predicted Values Operational System Hydrologic/Hydraulic Models Short Term Forecast Current States Deterministic Products Verification Software Verification Data/Graphics Probabalistic Products Archived Data Observed and Forecast Verification System

44 NWSRFS ESP Ensemble Generation Historical Data Forecast Ensemble of Precipitation Temperature Time Series Current Conditions: Soil Snow Reservoir Levels Streamflow NWSRFS Hydrologic Models

45 ESP Uses Long range seasonal water supply (months). Spring volume forecasts (weeks). Spring snowmelt peaks. Minimum flows for navigation, irrigation, environmental, recreation, etc.

46 Ensemble Streamflow Predicition NWSRFS Model States Trace Generation Statistical Analysis NWSRFS Model Parameters Probabilistic Forecast Historical Temp/Precip Analysis Window

47 ESP - Trace Ensemble Plot Each trace represents model output after using Precip data from a different year

48 Probability Interval Histogram

49 Official Regression Water Supply Forecasts ESP Forecast Information

50 Thank You!

Operational Hydrologic Ensemble Forecasting. Rob Hartman Hydrologist in Charge NWS / California-Nevada River Forecast Center

Operational Hydrologic Ensemble Forecasting Rob Hartman Hydrologist in Charge NWS / California-Nevada River Forecast Center Mission of NWS Hydrologic Services Program Provide river and flood forecasts