CBRFC WFO Call June16 - PowerPoint PPT Presentation

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CBRFC WFO Call June16

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Title: CBRFC WFO Call June16


1
CBRFC WFO CallJune16
2
Outline
  • Survey Results (Kevin 5 min)
  • CBRFC Summer Development Plan (Michelle 10 min)
  • CHPS update (Andy, John 10 min)
  • ET project update (Mike 10 min?)
  • June 5-10 event post-mortem (Various 30 min)
  • Other topics?

3
SH/MIC Survey Results
  • N6 (offices participating Las Vegas, Flagstaff,
    Tucson, Grand Junction, and Boulder)
  • Rating of CBRFC products and services
  • All offices value flood forecasts, flash flood
    support, and daily forecasts
  • Northern offices valued water supply, peak flow
    forecasts
  • Drought information and recreation forecasts less
    valuable
  • Key comments
  • Request QPF on par with CNRFCs QPF (Las Vegas)
  • Improved FFG (Grand Junction, Boulder)
  • Ability to specify duration for precipitation
    analysis (Grand Junction)
  • Mixed comments on quality of streamflow
    forecasts positive feedback on flooding event
    support and forecast quality (Flagstaff). Room
    for improvement on forecasts during spring melt
    (Grand Junction) and data sparse basins (Meadow
    Valley Wash and Muddy River in Vegas HSA)

4
CBRFC Development Plan
  • Improve daily operations
  • plot previous forecasts
  • revisit shifts to allow for forecasts to be
    issued quicker
  • Post-mortem study on June 2010 event
  • Water Supply
  • peak flow re-analysis
  • Improvements to weekly ESP web display
  • Study to relate snow and runoff for small basins
  • Revamp pub
  • Documentation (stick diagrams, IFPcompanion basin
    information)
  • Distributed Model
  • Work with WFO TWC over summer to evaluate FSR
    (FFG)

5
CBRFC Development plan - cont
  • Dam failure program
  • integrate EAPs into dam failure web site
  • training.
  • Outreach
  • Open house (Aug 18)
  • Utah User Engagement workshop (Aug 2)
  • visit WFO Riverton (July)
  • Arizona Hydrologic Symposium booth (September)

6
CBRFC Development plan - cont
  • Improve web services
  • Web speed
  • QC web page
  • Web services USU and CLDSS
  • Precipitation display (more flexibility to choose
    dates to accumulate over, etc.)
  • Improve products and services for USBR
  • CHPS
  • HEFS evaluation
  • Revisit CPC consolidation forecast
  • Begin systematic daily runs of CHPS over
    sub-area
  • Calibrations

7
CHPS (John L, Andy W)
  • CHPS Community Hydrologic Prediction System
  • The whole system, ie data collection, quality
    control, future forcing creation
  • Includes FEWS
  • FEWS Flood Early Warning System
  • The hydrologic modelling software
  • Within CHPS
  • Replaces NWSRFS

8
Current IFP interface with NWSRFS
9
New IFD interface for FEWS
  • Highlights of new features
  • More logging of system
  • Easier navigation of model plots
  • Better integration of segment information
  • Ability to view all data in system

10
Gridded data into FEWS QPF example
11
Gridded Temperatures and Freezing Levels will be
imported too
12
Other things to come with CHPS
  • Ability to provide Stand Alone systems.
  • Ability to add new models to the system.
  • Facilitate collaborations with academia, and
    research-to-operations implementations.
  • International hydrologic community.

13
Forecasting ETrc across NWS Western Region (Mike
Hobbins)
14
ET evapotranspiration Ep potential
evaporation ETrc reference crop
evapotranspiration
ET-related work in NWS WFOs, RFCs, WR-SSD, ABRFC
  • Calls for standardized ET, Ep, or ETrc output on
    www from forecasters, RFCs, extension agents, and
    within WR
  • Colorado Basin RFC
  • goal to improve RFC simulations and forecasts.
  • WFOs goals are often to provide ET grids to
    satisfy AG users
  • Great Falls WFO (MT) experimenting with Penman
    Ep.
  • Pendleton WFO (ne OR) publishing Kimberly
    Penman ETrc,
  • Hanford WFO (SJ valley, CA) publishing
    Penman-Monteith ETrc.
  • Sacramento WFO (int. n CA) publishing
    Penman-Monteith ETrc,
  • working with UC Davis and California DWR.
  • Arizona WFOs All AZ MICs agreed to host ET
    forecasts on their www
  • Western Region
  • regionwide team from various WFOs to create
    standardized ET webpage, primarily for ag users,
  • wants ET knowledge-base in-house,
  • MSD wants standardized procedure by spring 2010,
  • WR wants to coordinate their efforts with CBRFC
    ET work and goals.

15
RTMA Real-Time Mesoscale Analysis
ETrc across Western Region RTMA-driven
Penman-Monteith ETrc
  • in Penman-Monteith, ETrc is a specific case of ET
    calculated for specific biological and physical
    conditions (reference crop)
  • hypothetical, well-watered crop of height h
    0.12 m, rs 70 sec/m, a 0.23,
  • Uz, T, and ea data from 2-m height,
  • ra implicitly specified as 208/U2 sec/m.
  • international standard (FAO-56).
  • very commonly used in agricultural community.

24hrs from 12Z 5/3/2010
16
ETrc across Western Region RTMA-driven Kimberly
Penman ETrc
  • adjusts Penman Ep to model seasonality in vapor
    transfer process through aKP and bKP
  • seasonal functions of day of year,
  • calibrated in Kimberly, ID.

24hrs from 12Z 5/3/2010
17
ETrc across Western Region RTMA-driven ETrc
difference Kimberly Penman Penman-Monteith
24hrs from 12Z 5/3/2010
18
Radiative parameterization
Shortwave radiation balance, SWn
Longwave radiation balance, Ln
Net available energy, Qn
LWd
LWu
aSWd
SWd
ET
H
B
Ad
?W ?t
G
Ground heat flux
19
Western Region ETrc forecast goals
  • Forecast
  • operations
  • real-time
  • daily/weekly
  • Climatology
  • Jan 1980 Dec 2009
  • high resolution
  • unbiased wrt forecasts
  • Project goals
  • provide end-users with web-disseminated,
    fine-resolution, accurate, daily-to-weekly
    forecasts of ETrc across the NWS Western Region
    domain,
  • add value to the ETrc forecasts by generating and
    comparing to a 30-year climatology.

ETrc(t)
verification
ETrc(forecast)
statistical analysis
Value-added ETrc(forecast)
ETrc(climo)
experimental www publication
feedback from users
www publication
20
NLDAS North American Land Data Assimilation
Scheme NARR North American Regional
Reanalysis NDFD National Digital Forecast
Database RTMA Real-Time Mesoscale Analysis AEC
Areal Extent of Cloud
Data sets Climatology and forecasts
Present
Aug 06
Dec 09
1 day
7 days
Jan 79
biased wrt NDFD?
climatology
climatology
forecast
verifies NDFD
21
  • Unresolved issues
  • What products do the users want and/or expect?
  • forecast periods,
  • spatial resolution,
  • how often updated?
  • What do we tell the users we can offer?
  • Climatology
  • accessing RTMA history SKY
  • generating unbiased RTMA/NLDAS climatology
  • low-res NLDAS climo in experimental period,
    replacing with high-res RTMA/NLDAS unbiased climo
    later?
  • time-step for climatology statistics daily?
    multi-day? weekly?
  • if weekly moving average (365 surfaces)? static
    weeks (52)?
  • Verification
  • ETrc vs. Epan to check radiative
    parameterization?
  • anomaly behavior,
  • synthetic or observed Epan?
  • how do we check our forecast skill?

22
Post-Mortem for June 6-10 flooding
  • Forecasts generally poor and under simulated for
    peak flows that occurred June 6-10, 2010 in
    northern Utah and western Colorado
  • General conditions leading into event
  • Very cool May
  • Warm, moist air mass beginning June 5
  • Temperature forecasts generally good
  • SNOTEL sites in flooding catchments near average
    for this time of year
  • Streamflow forecasts were almost uniformly too
    low
  • Ongoing study to understand why
  • Preliminary results focus on Little Cottonwood
    Creek
  • What happened in the real world?
  • What happened in the model world?

23
Recent local Temperatures
  • May was generally cool, delayed melt
  • First week in June was warm
  • From
  • NOAA CPC

A cool May
A warm week
24
Little Cottonwood at Crestwood Parkflow
forecasts under-simulated
flood
bankfull
observed
forecasts
simulated
weekend
25
WFO Watches and warnings for Little Cottonwood
(Cottonwood, Crestwood Park hydrograph shown)
Flood Warning 543 PM MDT SUN JUN 6
Flood Watch 1132 AM MDT SUN JUN 6
Hydrologic Outlook (ESF) 330 PM MST SAT JUN
5 FLOODING IS NOT ANTICIPATED
weekend
26
Little Cottonwood snow year
  • Snowmelt rate extraordinarily large? (no)
  • Snowmelt extraordinarily late? (no)

2010
avg
27
Little Cottonwood at Crestwood Park Temp.
forecasts
Averaged over all elevation zones not bad!
observed
forecasts
weekend
28
Snotels in Cottonwoods
  • Mill-D North (8960, southwest face)
  • middle
  • Brighton (8750, southeast face)
  • middle
  • Snowbird (9640, northeast face)
  • high

Mill-D North
Brighton
Snowbird
29
SWE in Cottonwoods2010 compared to 2006
2006
Nearly identical melt!
2010
30
SWE melt comparison
  • Compared to 2005 and 2006 2010 had less SWE,
    but melt was more synchronized

2005
2006
2010
Lower vs upper meltout
30 days
20 days
5 days
31
SWE/Snotel Comparison
  • June Snowmelt at Snowbird in 2006 2010 were
    similar, but in 2006, snow at lower elevations
    was gone in 2010 there was synchronized, rapid
    melt at both elevations.
  • What about May 2006, when both zones were also
    melting? Melt rates were lower, particularly in
    upper zone (and flow response was smaller).

2010
2006
1.5 in/day
2.5 to 3 in/day
2 in/day
1.8 in/day
32
Snow Distribution corroborates presence of
lower elevation snow in 2010 at start of event
2010 June 1
2006 Snowbird SNOTEL trace almost identical to
2010 trace from June 1-10 However, NOHRSC
indicates south facing slopes had already melted
out in 2006
2006 June 1, for comparison
33
Streamflow Year Comparisons
  • Both 2005 and 2006 had bigger snowpacks
  • Flow peaks in prior years occurred after lower
    snow was gone
  • In 2005 and 2006, imagine combining the two melt
    pulses into one youd get a flood!

2010
Rainfall
2005
2006
34
What did the model think?
  • Model SWE at time of runoff was sufficient, and
    melt rates were close to observed rates
  • Overall shape of seasonal snowpack was good
    (compare to 38 peak at Snowbird)

Jun 3-8
2.8 in/day
2.6 in/day
35
What did the model think?
  • Model soil was on pretty dry in upper and middle
    levels entering event, and stored water

Jun 3-8
3-4 days melt soaked up
lower
upper
Deficits in model soil filling
middle
36
Was the model right about soil moisture?
  • Partly right 2010 was relatively dry
  • Partly wrong throughout winter, SM steadily
    moved upward toward normal levels
  • In model, this recovery started late and didnt
    get as far
  • 3-4 days of melt went by before model really
    started generating runoff

37
Preliminary Conclusions
  • The snowmelt that drove the flooding was
  • More rapid than normal (by about an inch per day)
  • From more area than normal (both middle and high
    elevations)
  • The cool May 2010
  • Delayed the melt of snow into June, holding lower
    elevation snow
  • Atmospheric moisture effects contributed little
    during the event, but prior month of cool,
    relatively moist conditions may have helped it
    ripen
  • CBRFC models under-simulated the streamflow
    response
  • The snow model performed well, simulating proper
    amounts and melt rates (with adjustment by
    forecasters)
  • SNOTEL soil moisture confirms that 2010 SM was
    relatively dry, but
  • The Sacramento hydrologic model soils may have
    been too dry, storing enough snowmelt during the
    event to buffer the flow response

38
SWE related mods? LCTU1 (Cottonwood _at_ SLC)only
melt factor was used
MFC 0.69
MFC 1.70
CFS
MFC 1.80 deleted 6/7
MFC 2.35 deleted 6/8, 6/10
MFC 1.47 deleted 6/9
Note, appears we did only one soil water mod
during May-June
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