Transcript Modeling Fundamentals

CNRFC
Operational Flood Forecasting
Pete Fickenscher
Hydrologist
California-Nevada River Forecast Center
National Weather Service
October 18, 2006
CNRFC Operations
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11 Weather offices
220 Basins modeled
87 Flood Forecast Points
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50 Reservoir Inflow Points
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Partners: Calif. DWR
Season: Oct. 15 – Apr. 15
Partners: COE & BUREC
Season: year-round
50 Water Supply Points
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Season: Jan.1 – Jul. 1
CNRFC Staff
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Hydrologist in Charge (HIC)
Development and Operations Hydrologist
(DOH)
4 Senior Hydrologists
3 Hydrologists
1 Senior HAS Forecasters
2 HAS Forecasters
Administrative Assistant
CNRFC Hydrologic Products
Short Range … … … … … … Long Range
Flash Flood Guidance
Flood Forecast Guidance
Reservoir Inflow Forecasts
Spring Snow Melt Forecasts
Water Supply Volume
Flood Forecasting Operations
QPF
River Forecasts
Operational Hydrologic Models
NWSRFS Structure
Operational
Forecast System
ESP
Calibration
System
Primary NWSRFS Models
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Rain-Snow Elevation
Snow-17
Sacramento Soil Moisture Accounting (SAC-SMA)
Unit Hydrograph
Reservoir Models
River Routing Models
NWSRFS Models
Rain-Snow Elevation
Snowfall
Rainfall
NWSRFS Models
SNOW-17
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Conceptual Model of Physical Processes
Models a Column of Snow
- Accumulation of Snow Cover
- Surface Energy Exchange
- Snow Cover ‘Ripening’
- Ground Heat Exchange
- Transmission of Liquid Water
Input = Air Temperature & Precip.
Output = Rain + Melt, SWE, & Areal Extent of Snow
NWSRFS Models
SNOW-17
WY 1986
SJ River
NWSRFS Models
SAC-SMA
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Conceptual Model of the Land Phase of the
Hydrologic Cycle
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Input = Rain + Melt, Evapotranspiration, Areal
Snow Cover
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Output = Inflow to the channel system
SAC-SMA
NWSRFS Models
SAC-SMA
WY 1986
SJ River
NWSRFS Models
Actual Inflow (FOLC1)
Observed (w): hourly data
Simulated (p): 6-hourly
(with reservoir outflows)
NWSRFS Models
River Routing Example
NWSRFS Models
Reservoir Model Example (Yolo Bypass)
NWSRFS Models
Tidal Example (Rio Vista)
Operational Hydrologic Models
NWSRFS Structure
Operational
Forecast System
ESP
Calibration
System
Operational Flood Forecasting
Hydrologist
hydrologic
expertise
H
QPF
A
Rain/Snow
Elevations
S
Forecast
Temp
River
Forecast
System
precip/temp/flow
Data
Systems
River Forecast
Guidance
Soil, snow & routing
parameters
Model
Calibration
Operational Flood Forecasting
Hydrologist
River Forecast
Guidance
Data
Systems
Model
Calibration
Precipitation Data Quality Control
Precipitation Data Quality Control
Gage Catch Issues
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Wind
Snow
Instrumentation (double tipping)
Gage location (vegetation, topography…)
Vandalism
River and Reservoir Data QC
Hourly
Stage & Streamflow
Reservoir Inflow
Outflow and Storage
Anticipated
Reservoir Outflow
Automated Filtering
&
Manual QC
Real-time Forecasting
NF American River
Observed Data
Simulated Flow
Real-time Forecasting
Folsom Inflow
Real-time Forecasting
San Joaquin River at Newman
Observed Flow Data
Simulated Flow
Operational Flood Forecasting
Operational Flood Forecasting
Hydrologist
River Forecast
Guidance
Data
Systems
Model
Calibration
Interactive Forecast Program
River Model
IFP Runtime Modifications
Operational Flood Forecasting
Hydrologist
Graphical RVF
hydrologic
expertise
H
QPF
A
Rain/Snow
Elevations
S
Forecast
Temp
River
Forecast
System
precip/temp/flow
Data
Systems
Soil, snow & routing
parameters
Model
Calibration
Graphical River Forecast Guidance
Merced River Pohono Bridge
Graphical RVF Availability
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87 official flood
forecast points.
Routine updates.
twice per day.
 morning/afternoon.
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Updates during floods.
8am/2pm/8pm/2am.
 as needed.
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Visible to everyone.
Graphical River Forecast Guidance
Benefits
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Visual image of meteorological and
hydrological situation.
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More information is presented than in a
text product.
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Longer range guidance for emergency
managers.
Forecasting
Balancing Timeliness and Accuracy
Timeliness
Accuracy
Forecast Lead Time
Graphical River Forecast Guidance
Guidance period information
has higher uncertainty.
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Timing and amount of rainfall
forecast.
Rain/snow level forecast.
Unanticipated reservoir
regulation will affect
downstream forecasts and
guidance.
New Website
http://www.cnrfc.noaa.
gov/
Graphical
RVF
New Website
http://www.cnrfc.noaa.
gov/
Other River
Guidance
Review of 2006 Flood Event
Folsom Inflow Forecasts
Graphs
Operational Hydrologic Models
NWSRFS Structure
Operational
Forecast System
ESP
Calibration
System
ESP Products
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Reservoir inflows
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Unregulated
rivers
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Extended
forecasts
AHPS – Relevant Products
ESP Custom Product Generation
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CNRFC
implemented
AHPS locations
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Started in WY2005
on 70 points
ESP Traces
AHPS – Relevant Products
ESP Custom Product Generation
CNRFC Development Areas
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Flood Forecasting
Dam Break Support
Flash Flood Support
Water Supply Forecasting
Hourly Hydrologic Modeling
Website
http://www.cnrfc.noaa.gov/
California-Nevada
River Forecast Center
Thank You