Site-Specific and Regional PMP Studies Current HMRs Completed - - PDF document
Site-Specific and Regional Probable Maximum Precipitation (PMP) Studies Ed Tomlinson, PhD 2009 Western Regional Dam Safety Forum San Francisco, California January 15, 2009 PO Box 680 Monument, Co 80132 (719) 488-9117 e-mail:
2009 Western Regional Dam Safety Forum San Francisco, California January 15, 2009
PO Box 680 Monument, Co 80132 (719) 488-9117 e-mail: awaadmin@comcast.net www.appliedweatherassociates.com
– Generalized (Hydrometeorological Reports, HMRs) – Site-Specific
EPRI Wisconsin/Michigan PMP Study 1993 Nebraska Statewide PMP Study 2008 Arizona Statewide PMP Study Begin Feb 2009
Approved Colorado Ohio New Jersey Nebraska New York Potential new studies Oregon California Virginia Pennsylvania
– Evaluate the use of HMR procedures for each storm type
– Moisture depletion by upwind mountain barriers – Precipitation enhancement/decrease – Effects on storm center location
– Identify inconsistent assumptions
– Select storms for each region – Transposition
same region
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
68 67 69 69 72 75 75 74 75 73 70 69 68 65 66 65 65 65 67 66
74
– Upwind moisture barrier defined – Sea surface temperatures used
Southeastern Inflow Barrier - South Arm to Sugarloaf Mountain Average Barrier Height - 830 Meters / 2725 Feet
100 200 300 400 500 600 700 800 900 1000 1100 1200 1300 1400 1 51 101 151 201 251 301 351 401 451 501 551 601 651 701 751 801 851 901 951 1001 1051
Cell Number Barrier Elevation (Meters)
Southeast M oisture Inflow Barrier - The G reen, Berkshire, and Taconic M ountains Average Barrier H eight M inus 100 Feet: 2040 Feet
50 0 1 00 0 1 50 0 2 00 0 2 50 0 3 00 0 3 50 0 4 00 0 20 4 0 6 0 8 0 10 0 12 0 1 40 16 0 B arrier W idth in M iles Barrier Height in Feet
Average Barrier H eight Average Barrier H eight M inus 100 Feet Barrier Terrain H eight
Northeast Moisture Inflow Barriers: Tuxedo Lake Drainage Basin Effective Barrier Height: 1400 feet
500 1000 1500 2000 2500 3000 Barrier 1 Average Elevation Barrier 2 Average Elevation Northeast Inflow Barrier 2 Northeast Inflow Barrier 1 Effective Barrier Height Northeast Inflow Barrier 1 Average Elevation: 1,461 feet Length: 66 miles Northeast Inflow Barrier 2 Average Elevation: 1,230 feet Length: 85 miles
Temporal Transposition Date 17-Aug Lat Long SSE@ 75 miles Stormcenter location 36.23 N 96.57 W 1,300 feet StormRepdewpoint location 35.23 N 96.06 W Storm E levation 930 feet Transposition dewpointlocation 40.20 N 95.88 W 1,300 feet Basin location 41.25 N 96.66 W 76.0 F with total precipitable water above sea level of 2.99 inches. 79.0 F with total precipitable water above sea level of 3.44 inches. 80.0 F with total precipitable water above sea level of 3.60 inches. 930 which subtracts 0.24 inches of precipitable water at 76.0 F 930 which subtracts 0.27 inches of precipitable water at 79.0 F 1,300 which subtracts 0.38 inches of precipitable water at 80.0 F 1,300 which subtracts 0.38 inches of precipitable water at 80.0 F 1.15 1.02 1.00 1.17 6Hours 12Hours 18 Hours 24Hours 30 Hours 36Hours 48 Hours 60Hours 72 Hours 18.4 23.4 23.6 23.6 23.6 23.6 0.0 0.0 0.0 14.7 19.2 19.4 19.6 19.7 19.8 0.0 0.0 0.0 12.5 17.6 17.8 18.0 18.1 18.3 0.0 0.0 0.0 9.7 15.4 15.6 15.7 15.8 16.2 0.0 0.0 0.0 7.9 13.3 13.4 13.6 13.7 14.1 0.0 0.0 0.0 4.3 7.3 7.4 7.5 7.7 7.8 0.0 0.0 0.0 3.0 5.3 5.4 5.5 5.6 5.7 0.0 0.0 0.0 2.0 3.9 4.1 4.2 4.3 4.4 0.0 0.0 0.0 6Hours 12Hours 18 Hours 24Hours 30 Hours 36Hours 48 Hours 60Hours 72 Hours 21.5 27.4 27.6 27.6 27.6 27.6 0.0 0.0 0.0 17.2 22.5 22.7 22.9 23.1 23.2 0.0 0.0 0.0 14.6 20.6 20.8 21.1 21.2 21.4 0.0 0.0 0.0 11.4 18.0 18.3 18.4 18.5 19.0 0.0 0.0 0.0 9.3 15.6 15.7 15.9 16.0 16.5 0.0 0.0 0.0 5.0 8.5 8.7 8.8 9.0 9.1 0.0 0.0 0.0 3.5 6.2 6.3 6.4 6.6 6.7 0.0 0.0 0.0 2.3 4.6 4.8 4.9 5.0 5.2 0.0 0.0 0.0 Stormor StormCenter Name Hallett, OK StormDate(s) 2-Sep-1940 StormType MCC StormLocation 36.23 N 96.57 W StormCenter Elevation 930 Precipitation Total & Duration 24.00 Inches 12-hours USACE StormStudies SW 2-18 StormRepresentative Dewpoint 76.0F 12hr average StormRepresentative Dewpoint Location 35.23 N 96.06 W MaximumDewpoint 79.0F Moisture Inflow Vector SSE@ 75Miles In-place Maximization Factor 1.15 Temporal Transposition (Date) 17-Aug Transposition Dewpoint Location 40.20 N 95.88 W Transposition Max imumDewpoint 80.0F Basin Elevation 1,300 Transposition to Basin Adjustment Factor 1.02 Higherof Basin Elevation - Inflow Barrier Height 1,300 Elevation Adjustment Factor 1.00 Total Adjustment Factor 1.17 200 sq miles 500 sq miles 10 sq miles 100 sq miles The barrieradjustment factor is The total adjustment factor is The inflow barrier/basin elevation height is The transposition/elevation to basin factor is Hallett, OK StormName: StormDate: AWA Analysis Date: 5/10/2007 02-Sep-1940 1000 sq miles 5000 sq miles 1000 sq miles 10000 sq miles 20000 sq miles 10 sq miles 5000 sq miles 10000 sq miles 20000 sq miles
Storm Adjustment for Wanahoo, NE
AdjustedStorm Depth-Area-Duration Observ edStormDepth-Area-Duration 100 sq miles 200 sq miles 500 sq miles The in-place stormmaximization factor is The in-place stormelevation is The transposition basin elevation at Moisture InflowDirection: Basin E levation E ffective Barrier Height Notes:DAD values taken fromUSACEStorm Studies SW 2-18 The stormrepresentative dew point is The in-place maximumdew point is The transpositioned maximumdew point is The in-place stormelevation is
Stormor StormCenter Name Hallett, OK StormDate(s) 2-Sep-1940 StormType MCC StormLocation 36.23N 96.57 W StormCenter Elevation 930 Precipitation Total & Duration 24.00Inches 12-hours USACE StormStudies SW 2-18 StormRepresentative Dewpoint 76.0F 12hr average StormRepresentative Dewpoint Location 35.23N 96.06 W MaximumDewpoint 79.0F Moisture Inflow Vector SSE@ 75Miles In-place Max imization Factor 1.15 Temporal Transposition (Date) 17-Aug Transposition Dewpoint Location 40.20N 95.88 W Transposition MaximumDewpoint 80.0F Basin Elevation 1,300 Transposition to Basin Adjustment Factor 1.02 Higher of Basin Elevation - Inflow Barrier Height 1,300 Elevation Adjustment Factor 1.00 Total Adjustment Factor 1.17
Temporal Transposition Date 17-Aug Lat Long SSE@ 75 miles Stormcenter location 36.23 N 96.57 W 1,300 feet StormRepdewpoint location 35.23 N 96.06 W Storm E levation 930 feet Transposition dewpoint location 40.20 N 95.88 W 1,300 feet Basin location 41.25 N 96.66 W 76.0 F with total precipitable water above sea level of 2.99 inches. 79.0 F with total precipitable water above sea level of 3.44 inches. 80.0 F with total precipitable water above sea level of 3.60 inches. 930 which subtracts 0.24 inches of precipitable water at 76.0 F 930 which subtracts 0.27 inches of precipitable water at 79.0 F 1,300 which subtracts 0.38 inches of precipitable water at 80.0 F 1,300 which subtracts 0.38 inches of precipitable water at 80.0 F 1.15 1.02 1.00 1.17 The barrier adjustment factor is The total adjustment factor is The inflow barrier/basin elevation height is The transposition/elevation to basin factor is Hallett, OK StormName: StormDate: AWA Analysis Date: 5/10/2007 02-Sep-1940
Storm Adjustment for Wanahoo, NE
The in-place stormmaximization factor is The in-place stormelevation is The transposition basin elevation at Moisture InflowDirection: Basin E levation Effective Barrier Height Notes: DAD values taken fromUSACEStorm Studies SW 2-18 The stormrepresentative dew point is The in-place maximumdew point is The transpositioned maximumdew point is The in-place stormelevation is
6Hours 12Hours 18 Hours 24Hours 30 Hours 36Hours 48 Hours 60Hours 72 Hours 18.4 23.4 23.6 23.6 23.6 23.6 0.0 0.0 0.0 14.7 19.2 19.4 19.6 19.7 19.8 0.0 0.0 0.0 12.5 17.6 17.8 18.0 18.1 18.3 0.0 0.0 0.0 9.7 15.4 15.6 15.7 15.8 16.2 0.0 0.0 0.0 7.9 13.3 13.4 13.6 13.7 14.1 0.0 0.0 0.0 4.3 7.3 7.4 7.5 7.7 7.8 0.0 0.0 0.0 3.0 5.3 5.4 5.5 5.6 5.7 0.0 0.0 0.0 2.0 3.9 4.1 4.2 4.3 4.4 0.0 0.0 0.0 6Hours 12Hours 18 Hours 24Hours 30 Hours 36Hours 48 Hours 60Hours 72 Hours 21.5 27.4 27.6 27.6 27.6 27.6 0.0 0.0 0.0 17.2 22.5 22.7 22.9 23.1 23.2 0.0 0.0 0.0 14.6 20.6 20.8 21.1 21.2 21.4 0.0 0.0 0.0 11.4 18.0 18.3 18.4 18.5 19.0 0.0 0.0 0.0 9.3 15.6 15.7 15.9 16.0 16.5 0.0 0.0 0.0 5.0 8.5 8.7 8.8 9.0 9.1 0.0 0.0 0.0 3.5 6.2 6.3 6.4 6.6 6.7 0.0 0.0 0.0 2.3 4.6 4.8 4.9 5.0 5.2 0.0 0.0 0.0 200 sq miles 500 sq miles 10 sq miles 100 sq miles 1000 sq miles 5000 sq miles 1000 sq miles 10000 sq miles 20000 sq miles 10 sq miles 5000 sq miles 10000 sq miles 20000 sq miles AdjustedStorm Depth-Area-Duration Observed StormDepth-Area-Duration 100 sq miles 200 sq miles 500 sq miles
Twenty-Four-Hour Depth-Area Curves for Maximized and Transpositioned Storm Events In the Great Sacandaga Lake Drainage Basin
1 10 100 1000 10000 100000 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Rainfall Depth in Inches Storm Area in Square Miles
Westfield, Massachusetts Easton, Maryland Buck, Connecticut Zerbe, Pennsylvania Paterson, New Jersey York, Pennsylvania Peekamoose, New York Gorham, Maine Hector, New York Near Bolton, Canada Ripogenus Dam, Maine Canton, Connecticut
Newark, New Jersey Hartford, Ct Enveloping Curve HMR 51
– Pat Diederich
– Mark Anderson, PhD
– Barry Keim, PhD
– Identify historic extreme rainfall events – Analyze the storm Depth-Area-Duration (DAD) rainfall amounts
– Maximize the storm rainfall “in-place”
produced if more moisture were available?
– Transposition the storm to Nebraska
maximum rainfall produced?
– Complete a storm search to identify the most significant storms that could have potentially occurred over various locations in Nebraska
– A review of characteristics associated each storm type will be provided
for new storms and re-evaluated for old storms
– Perform storm maximization and transpositioning of the most extreme storms various regions in Nebraska – 6-hour, 12-hour and 24-hour average maximum dewpoint values were used for storm maximization and transpositioning – New 6-hour, 12-hour and 24-hour average maximum dewpoint climatologies were computed
where possible
it may not possible to explain the source of the differences between site-specific PMP values and the generalized HMR 51 PMP values
– Create a grid covering Nebraska and portions of surrounding states – Perform storm maximization and transpositioning of the most extreme storms to each of the grid point locations – 6-hour, 12-hour and 24-hour maximum average dewpoint values will be used for storm maximization and transpositioning – DAD curves for the largest transpositioned and maximized storms will be plotted at each grid point
– Search the National Climatic Data Center (NCDC) hourly and daily rainfall records – Identify maximum 6-hr, 24-hr/1-day, and 72-hr/3- day rainfall amounts within a the search box
– Additional data mining was done using the National Weather Service (NWS), National Oceanic and Atmospheric Administration (NOAA), and NCDC web services, various American Meteorological Society (AMS) journals, and Google internet storm searches
Storm Search Box With Storm event locations for the maximum 6-hr rainfall storm search
area-duration (DAD) analysis system
Information Systems (GISs)
National Weather Bureau
mid-50’s
after they occur
Engineers completed detailed storm analyses for storms that occurred from the 1880’s through the 1950’s
selected storms have been analyzed (e.g. Hurricanes Camille 1969 and Agnes 1972)
storm analyses
validation greatly benefit from accurate and detailed storm analyses
compared favorably to previously analyzed storms, including:
1955
June 7, 1953
SPAS Sq-Miles 6-hour 12-hour 24-hour 36-hour 48-hour 60-hour Total 10 7.96 11.48 16.40 19.10 19.11 19.47 19.70 100 7.22 10.72 15.20 17.77 17.76 18.23 18.47 200 6.99 10.27 14.28 16.91 16.84 17.39 17.54 1000 5.97 9.06 12.55 14.97 15.08 15.40 15.95 5000 4.14 6.45 9.25 11.70 12.02 12.35 13.05 10000 3.23 5.46 7.63 9.60 9.91 10.26 10.86 20000 2.24 4.03 5.91 7.66 7.97 8.22 8.77 Weather Bureau Sq-Miles 6-hour 12-hour 24-hour 36-hour 48-hour 60-hour Total 10 7.80 11.10 16.40 18.90 19.40 19.40 19.40 100 7.60 10.50 14.60 18.10 18.80 19.00 19.00 200 7.40 10.20 14.20 17.60 18.20 18.40 18.40 1000 6.20 9.20 12.40 15.90 16.20 16.40 16.40 5000 4.00 6.30 9.50 12.10 12.60 13.00 13.00 10000 3.10 5.00 8.00 10.00 10.60 10.80 10.80 20000 2.10 3.60 6.30 7.90 8.30 8.50 8.50 Percent Difference Sq-Miles 6-hour 12-hour 24-hour 36-hour 48-hour 60-hour Total 10 2.1% 3.4% 0.0% 1.1%
0.4% 1.5% 100
2.1% 4.1%
200
0.7% 0.6%
1000
1.2%
5000 3.5% 2.4%
0.4% 10000 4.2% 9.2%
0.6% 20000 6.7% 11.9%
3.2%
Generally within +/- 5% !!
hourly grids/maps.
Total storm (Hurricane Floyd) precipitation, New Jersey, September 14-18, 1999.
precipitation grids serve as the basis for much of the output statistics Hourly precipitation ending at 4 PM EST September 16, 1999 associated with
Hurricane Floyd.
the least square fit of the the Z-R equation to the available hourly rainfall observations
covered by the NEXRAD
– For each hour of the storm – At a spatial resolution of approximately 1 square kilometer
Storm 1033 - Ogallala, NE July 6 (300 Z) - July 7 (600 Z), 2002
MAXIMUM AVERAGE DEPTH OF PRECIPITATION (INCHES)
Duration (hours) Area (mi2) 1 2 3 4 5 6 12 18 24 28 total 1 5.18 6.51 8.45 10.06 11.61 13.19 14.77 14.78 14.92 14.92 14.92 10 3.90 5.40 7.95 9.53 11.04 12.54 14.39 14.41 14.53 14.57 14.57 20 3.52 5.23 7.65 9.17 10.66 12.12 14.00 14.01 14.12 14.16 14.16 30 3.28 5.12 7.47 8.93 10.38 11.79 13.57 13.60 13.74 13.74 13.74 40 3.10 4.96 7.30 8.69 10.08 11.47 13.22 13.25 13.36 13.39 13.39 50 2.95 4.86 7.14 8.50 9.85 11.18 12.90 12.93 13.05 13.08 13.08 60 2.83 4.75 7.00 8.29 9.57 10.90 12.61 12.63 12.77 12.78 12.78 70 2.71 4.64 6.85 8.13 9.41 10.65 12.34 12.36 12.50 12.51 12.51 100 2.39 4.37 6.46 7.67 8.88 10.06 11.66 11.69 11.84 11.84 11.84 200 2.09 3.72 5.49 6.69 7.78 8.79 10.22 10.30 10.46 10.46 10.46 500 1.65 2.89 4.09 5.07 6.04 6.70 8.14 8.34 8.50 8.51 8.51 1,000 1.19 2.21 3.06 3.82 4.54 5.11 6.24 6.59 6.75 6.76 6.76 5,000 0.41 0.84 1.11 1.40 1.72 2.00 2.68 3.09 3.23 3.25 3.25
Six-Hour Depth-Area Curves for Maximized and Transpositioned Storm Events In the Lake Wanahoo Drainage Basin
1 10 100 1000 10000 100000 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
Rainfall Depth in Inches Storm Area in Square Miles
Big Rapids, MI Bonaparte, IA Boyden, IA Collinsville, IL Cooper, MI Council Grove, KS Edgerton, MO Grant Township, NE Greeley, NE Ida Grove, IA Hayward, WI HMR 51 Hallett, OK Ironwood, MI Lambert, MN Medford, WI Meeker, OK Minneapolis, MN Paris Waterworks, IN Ritter, IA Stanton, NE Tomah, WI Warner, OK Cole Camp, MO Beaulieu, MN Enid, OK Forest City, MN Hale, CO Holly, CO Ogallala, NE Pawnee Creek, CO Savageton, WY Springbrook, MT
Seventy-Two-Hour Depth-Area Curves for Maximized and Transpositioned Storm Events In the Lake Wanahoo Drainage Basin
1 10 100 1000 10000 100000 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40
Rainfall Depth in Inches Storm Area in Square Miles
Beaulieu, MN Big Rapids, MI Boyden, IA Collinsville, IL Council Grove, KS Edgerton, MO Hayward, WI Ironwood, MI Lambert, MN Medford, WI Meeker, OK Stanton, NE Warner, OK HMR 51 Cole Camp, MO Enid, OK Forest City, MN Pawnee Creek, CO Savageton, WY Springbrook, MT David City, NE Prague, NE Envelop