MacAloney Hydro Managers Conference 2004

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National Weather Service Flood Flash Flood
Verification Programs
Brenton MacAloney II Meteorologist Office of
Climate, Water, and Weather Services Performance
and Awareness Division December 8th, 2004
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National Weather Service Verification Program
Presentation Outline

• flash flood warning verification
• history
• creation of verification statistics (matching
  of warnings and events)
• stats on demand
• verification examples
• future projects impacting FFW verification
• flood warning verification
• status report

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National Weather Service Verification Program
History

• 1979 Severe local storm warning verification
  begins at the
• National Severe Storms Forecast Center
  (NSSFC)
• 1995 Warning verification program is
  transferred from NSSFC
• to National Weather Service Headquarters
  (WSH)
• -- Two contractors are hired at WSH
  to migrate the program
• 1996 Modernized warning verification program
  is
• implemented with real-time quality control of
  warning and event import
• 1998 Stats on Demand is created for
  tornado, flash flood,
• and severe thunderstorm warnings

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National Weather Service Verification Program
Collection of Flash Flood Warnings
Flash Flood Warnings are disseminated from the
WFOs via several methods including the AWIPS
network and are collected on our data servers in
Kansas City, MO. Warnings are downloaded to WSH
and we immediately attempt to import them subject
to quality control created based on National
Weather Service Policy Directives written on
warning formatting. Warnings not meeting the
import criteria are rejected. Events occurring
during the valid time of these erroneous warnings
will be counted as unwarned unless a properly
issued warning correction is issued. The
Performance Branch offers an alert service which
can notify you via e-mail or the AWIPS
workstation if a warning was not formatted
properly.
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National Weather Service Verification Program
Collection of Flash Flood Events

• All 123 WFOs are responsible for
• recording every verifiable flash
• flood event in their CWA
• Events are logged in the StormDat
• program which creates a database
• called storm data
• Storm data is sent to WSH up to 60
• days after the end of each month
• WSH uses storm data entries as
• the verifying events in its
• verification program.

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National Weather Service Verification Program
Matching of Warnings and Events

• Matching of events and warnings is done on the
  first business
• day of every month.
• The matching process takes approximately 5-7
  hours

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National Weather Service Verification Program
Flash Flood Warning and Event Collection Overview
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National Weather Service Verification Program
Stats on Demand

• Overview
• Web based program
• Designed for customized verification
• requests on demand
• Data available
• FLASH FLOOD 1986 2004
• TORNADO 1986 2004
• SEVERE TSTM 1986 2004
• SPECIAL MARINE 2001 2004
• Reports available
• Report Summary
• Report by Forecast Office
• Report by County/Zone
• Detailed Report (broken out by
• every event and warning)

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National Weather Service Verification Program
Stats on Demand Output Example
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National Weather Service Verification Program
Stats on Demand Output Example
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National Weather Service Verification Program
Flash Flood Verification Example 1
300am
900am
Warning 1
500am
800am
Flash Flood Event
WARNING SCORES 1 warning, verified EVENT
SCORES 1 event, warned, with a 120 minute
lead time
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National Weather Service Verification Program
Flash Flood Verification Example 2
100pm
300pm
Warning 1
500pm
Warning 2
200pm
400pm
Flash Flood Event
WARNING SCORES 2 warnings, both verified EVENT
SCORES 1 event, warned, with a 60 minute
lead time
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National Weather Service Verification Program
Flash Flood Verification Example 3
1015am
300pm
Warning 1
1000am
200pm
Flash Flood Event
WARNING SCORES 1 warning, verified EVENT
SCORES 1 event, warned, with a 0 minute
lead time
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National Weather Service Verification Program
Future Flash Flood Verification Projects

• Polygon warning verification
• (see graphic to the right)
• Comma delimited data output
• from Stats on Demand
• Graphical data output from
• Stats on Demand

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National Weather Service Verification Program
Flood Warning Verification Status Report

• requirements have been submitted to the
  Verification
• Unit for the development of a Flood Warning
  (FLW)
• verification program
• the requirements call for verification of areal
  flood
• warnings and river point flood warnings
• development is being held up by VTEC
• once all FLW products are issued with VTEC, we
  can
• start collection of events and warnings while
  
• development is taking place

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National Weather Service Verification Program
Contact Information
Brenton W. MacAloney II Phone [phone]
x135 E-mail Brent.MacAloney_at_noaa.gov
Please feel free to grab a business card from me
if you would like more information on the
National Weather Service Verification Program.