AMBER/FFMP Overview COMET Basin Customization August 2002 Robert S. Davis, Pittsburgh NWSWFO

AWIPS Flash Flood Monitoring and Prediction (FFMP) AWIPS build (Early 2002) the AMBER implementation of FFMP using DHR. Requires NSSL CD of ArcView defined watersheds and WSR-88D bin assignments. Provides graphic display of ABR and ABR–FFG for time periods of 30,60,90,120,180,360 minutes. Provides line graph of ABR,ABR Rate, and FFG for the same time periods. 1 level of streams supported FFMP small subset of AMBERGIS functionality.

FFMP Graphics County display of CWA-maximum ABR for any stream in county displayed. Left click on Fips code to get “stream display”. Stream display for a county- ABR for time period selected displayed for each basin. right click on stream ID to get “line graph”. Line graph of ABR + ABR Rate + FFG

Worthville, PA Flash Flood 05 June 2002 Jefferson County, PA

FFMP Text Data on AWIPS Where is your WSR-88D ID

FFMP file archiving ABR file is archived to hard disk on AWIPS for current GMT day and previous day only. + yyyymmdd.index for a GMT day Index file holds the time for each volume scan. Date file holds the ABR data for each stream (integer*2 data with a record length equal to 2 times the number of FFMP watersheds).

FFMP Basin Attributes /basinToCounty.dat /binToBasin.dat Radar bins are numbered consecutively from 0 to starting with radial 0.5 degrees. Bin 0 = 0.5 degrees at 0.5 km, bin 230 = 1.5 degrees at 0.5km, etc.

basinList.dat First line in file is number of basins (5609) Basin ID number in FFMP display is position in this file basin id =0 (2 nd line), 1 (3 rd line), 2 (4 th line), 3 (5 th line), etc. Pfafstetter ID Latitude/longitude of basin centroid Name of creek

binToBasin.dat First line is number of basins Second line is data for watershed id=0 1 st element (number of bins assigned) Bin number for each assigned bin follows, if 3 bins assigned to this stream, 3 bin numbers will be listed. Last element: area of bin summation (km 2 )

basinToCounty.dat Number of counties on first line Two letter state County name County Fips code Number of streams assigned to this county List of Basin Ids assigned to this county County assigned by MDL lat/lon of centroid

Stream Basin Definitions

National Basin Delineation 30Sep1999 – NWS agrees to fund the AMBER National Basin Delineation project by NSSL for all of the continental United States. ArcInfo used to define the watershed boundaries. USGS 1 arc second (30 m) DEM data supplied by EROS Data Center. Continental U.S. completed June 2002.

229.5 km Range ring NSSL Basins 18,488 Aggregated 12,784 Aggregate: Clip all basins beyond 230 km Eliminate all segments < 2 mi 2

FFMP Basins 5,608 NSSL CD FFMP

Purpose of the Basin Customization Course To describe the content of the NSSL dataset (ArcView shapefiles and data attributes). To provide tools that allow the local forecast office to modify, correct, or enhance the NSSL set of defined basins. To demonstrate why modifications or additions may enhance the application of FFMP to the flash flood warning process.

Choices: Customization Options No Customization (used delivered cd) Minor Customization (add stream names, make minor adjustments to basins to correct errors) Must still run localization. Major Customization (add new streams, divided existing streams) Paul’s procedure for hydrologic connectivity, allows use of Paul’s tools.

Choices: Display options at WFO Display FFMP graphics as delivered Run Paul Jendrowski’s AMBER for more stream layers, 7 AWIPS radar graphic products including ABR rate + 6 user selected time periods, AMBER browser, and line graph of past 6 hours. Use ArcView as display for geographic information.

Areal Mean Basin Estimated Rainfall ( AMBER) All watersheds in county warning area are defined to a Minimum Basin Area (MBA) of 2 mi 2 to show spatial rainfall distribution. The WSR-88D polar grid (1 o by 1 km) is mapped to the defined watersheds. Average Basin Rainfall (ABR) is computed for each watershed every volume scan. An hourly ABR rate is determined from the single volume scan (5-6 min.) of ABR.

AMBERGIS (2000 – 2002) Paul Jendrowski creation using ArcView. ABR data computed and archived (5 min). AWIPS ABR Rate display of radar umbrella. AWIPS ABR graphic display of radar umbrella for 6 user selected time periods. Line graph of ABR, ABR Rate, and FFG for each defined stream and rain gage. Nine layers of streams or rain gages supported. Alert for 3 user selected levels of ABR - FFG.

Graphical Radar Rainfall OHP – One hour rainfall STP – Storm total rainfall THP – Three hour rainfall

Storm Total Rainfall 19 May1999 Grid 1 o x 2km

AMBER/FFMP Digital Rainfall AMBER/FFMP computes 5 minute rainfall using WSR-88D precipitation algorithm with Digital Hybrid Scan Reflectivity (DHR) product as input.

Digital Hybrid Scan Reflectivity (DHR) Time interval (5-6 minutes) Grid size (1 degree x 1 km) Reflectivity to the nearest 0.5 dBZ

DHR Grid Area (km 2 ) vs. Radar Range (km)

DHR Digital Rainfall Estimate 2130 – 2135 UTC Rainfall (in) Grid size 1 o x 1km

DHR Digital Rainfall Estimate 2130 – 2135 UTC Rainfall (mm) Watershed Boundary…compute ABR

Average Basin Rainfall = – 2135 UTC ABR (in).29 Copy ABR back into DHR grid for FFMP or AMBERGIS graphics

Average Basin Rainfall = – 2135 UTC ABR (in) Divide watershed into segments??

Average Basin Rainfall =.29 in 2130 – 2135 UTC ABR (in) Large variation of ABR in short distances!!

Flash Flood Index (FF) FF = ABR - FFG Determining the Flash Flood Threat

Flash Flood Guidance (FFG) ABR in a specific time period (1, 3 hours) to initiate flooding on streams. Assumes stream at low flow level. Assumes no rainfall since data cutoff FFG is the amount of ABR needed to produce threshold runoff (climatic average runoff needed to start flooding of streams)

Flash Flood Guidance (FFG) FFG = TR + SM, where TR is the threshold runoff and SM is the amount of ABR needed to initiate runoff based on soil moisture content. Threshold runoff is constant for all watersheds 1.00” in three hours for most of eastern U.S (0.75” for western PA + WV). Ask your servicing RFC for your TR!!!

FF Index = ABR - FFG ABR and FFG in inches FF0 ABR = FFG FF1 ABR = FFG inches FF2 ABR = FFG inches FF3 ABR = FFG inches FF4 ABR = FFG inches FF5 ABR = FFG inches, etc

Noble County, OH Almost a flash flood. ABR-FFG = June UTC 1-Hour FFG = 1.70

FFMP Graphic Products vs. AMBERGIS Graphics

FFMP FFG

AMBER ABR-Rate AMBER 90-min ABR AMBER 120-min ABR

AMBER 60-min ABR

Change FFG Curve

Little Pine Creek Flash Flood 30 May 1986 ABR-FFG=5.0

Pine Creek Watershed 68 mi 2 ID Name Area 1000 L Pine Cr L Pine Cr Gourdhead Run Crouse Run Willow Run Montour Run NF Pine Cr Headwaters 13.9 Allegheny River Pine Creek Flash Flood Bucket Survey (inches) 30 May

Little Pine Creek 30 May 1986 Area: 6.2 mi 2 Little Pine Creek 30 May 1986 Area: 6.2 mi 2 Time (UTC)

Zion National Park Flash Flood 27 July 1998

3.30 1:30 1: :45 End of Trail Start of Trail Estimated hiking Time in hours. Deep Creek Kolob Creek Goose Creek Corral Hollow Orderville Canyon North Fork Virgin River The Narrows Hiking Trail Zion National Park, Utah Adapted from National Geographic Trails Illustrated “The Narrows” No safe high ground

Hiking in the “Narrows”

Washington County Kane County Iron County Orderville Canyon North Fork of the Virgin River Deep Creek The Narrows Kolob Creek EPA RF3 Data

Orderville Canyon Mouth into the Narrows

Deep Creek mi 2 NF Virgin River 70.3 mi 2 Orderville Canyon 41.5 mi 2 Kolob Creek 30.1 mi 2 Goose Cr 4.7 mi 2 Corral Hollow 2.2 mi 2 Imlay Canyon 3.8 mi 2 NF Virgin River above the Narrows 285 mi 2 The Narrows 4.1 mi 2 ABR (in) UTC 27 July km KICX WSR-88D 1-hour FFG 0.50

KICX WSR-88D 010km Deep Creek mi 2 NF Virgin River 70.3 mi 2 Orderville Canyon 41.5 mi 2 Kolob Creek 30.1 mi 2 NF Virgin River above the Narrows 285 mi 2 ABR (in) UTC 27 July hour FFG 0.50

1004 Goose Creek Corral Hollow Imlay Canyon North Fork of the Virgin River Orderville Canyon Deep Creek Kolob Creek North Fork of the Virgin River above the Narrows xx.x = miles above trail head The Narrows

Deep Creek (5) # July mi 2

Maximum Bin 176 o at 20 km 27July1998 Maximum rainfall on Storm Total Product 3.14 in.

Washington County Kane County mi mi mi mi mi 2 North Fork of the Virgin River above the Narrows 70.3 mi ABR (in) 27 July UTC “The Narrows” NF Virgin River (1-5) 3.14

NF Virgin River (2) # July mi 2

Washington County, UT Kane County, UT NF Virgin River Subdivisions Straight Canyon(1-3) NF Virgin River(2-4) 5006 Willow Canyon 5007 Hay Canyon 5008 Simon Gulch 5009 NF Virgin River(1) 5010 Rosy Canyon 5011 Stevens Canyon 5012 Ashdown Canyon ABR 27 July UTC 3.14

NF Virgin River(2) # July mi 2

NF Virgin River(3) # July mi 2

NF Virgin River(4) # July mi 2

Willow Canyon # July mi 2

Straight Canyon(2) # July mi 2

ABR Rates NF Virgin River 27July1998

AMBER Summary ABR provides basin specific rainfall to determine flash flood risk (ABR-FFG) ABR rate focuses forecaster attention on critical streams before flooding occurs. History (6-72 hours) of ABR helpful in adjusting FFG for multiple rainfall events. Basin specific ABR allows forecaster to mention “threat area” in warning text.

AMBER Data Sources ArcView and the spatial analyst extension. USGS Data (3 arc second DEM data) edcwww.cr.usgs.gov EPA Data (RF3 data files)

AMBER Case Studies buff.ppt 13Jul96 epgh99.ppt 18May99 pitcairn.ppt 01Jul97 zion.ppt 27Jul98 ohio98.ppt 26Jun98 redbank.ppt 19Jul96 dallas95.ppt 05May95 ftc97.ppt 28Jul97 kc1998.ppt 05Oct98 Buffalo Creek, CO Pittsburgh, PA Cedar City, UT Eastern Ohio Brookville, PA* Dallas, TX* Fort Collins, CO* Kansas City, MO* * Tropical Z/R Cases