High Impact Weather Events – A Challenge for Hazard Mitigation and Flood Response Plans

StoepherSession: F-4

830AM-1000AM Thursday, May 19, 2011

John F. Henz, C.C.M & Mat Mampara, P.E.

Dewberry – Denver CO Dewberry – Fairfax VA

John Henz

Family medical emergency I apologize for my abscence

What is high impact weather?

Low-impact – minor inconvenience, small and local economic losses, etc.

Moderate-impact – minor damage, some social disruption, etc.

High-impact – damage, risks to health, broad economic impact, etc.

Extreme-impact – Catastrophic losses, deaths, injuries, major social disruption, etc.

DEFINING THE IMPACT OF WEATHER, Patrick McCarthy , http://ams.confex.com/ams/22WAF18NWP/techprogram/program_414.htm

What is high impact weather?

Low-impact – minor inconvenience, small and local economic losses, etc.

Moderate-impact – minor damage, some social disruption, etc.

High-impact – damage, risks to health, broad economic impact, etc.

Extreme-impact – Catastrophic losses, deaths, injuries, major social disruption, etc.

DEFINING THE IMPACT OF WEATHER, Patrick McCarthy , http://ams.confex.com/ams/22WAF18NWP/techprogram/program_414.htm

What is being impacted?

1) People – individuals, families, workers, personal property, their work, lifestyles, health, etc.

2) Society – communities, healthcare, infrastructure, emergency response, etc.

3) Economy – transportation, recreation, tourism, agriculture, aviation, etc.

4) Environment – air, water, land

April 27/28, 2011 Tornado Outbreak

Deaths1. Tri-State Tornado Outbreak:

747+2. Tupelo/Gainsville Outbreak: 4363. Super Outbreak II: 341

Tuscaloosa, Alabama

Before and after

April 27 tornado outbreak storm rotation tracks – Nat.

Severe Storms Lab

Killer tornado tracks

April 27/28, 2011 NWS Severe t-storm, Flood and Tornado Warnings

While severe weather got the headlines another insidious threat lurked near

Early snow melt and rains over northern plains drove a head of flooding down the Mississippi.

Heavy rainfall preceded the tornado outbreak in the three days before April 27

During the tornado outbreak, numerous flash floods blocked roads, required evacuations and strained emergency services. Some examples:

April 26, 2011: 6-12in+ rains and flooding before tornadoes

April 27, 2011– Memphis NWS WSR-88D: many areas with > 6 inch rains

April 27, 2011: Little Rock NWS WSR-88D: many areas with > 6 inch rains

April 22-29, 2011 rainfall totals

May 8, 2011 flooding > 12 states

…….. and 2011 is not over yet …….

1974 vs. 2011 Climate similarities: Record snows in upper plains, Mid-

West and Eastern seaboard followed by rains & floods.

Record tornado outbreak in April.

Third high likelihood: a hurricane strike along the Gulf Coast in August or September?

Hurricanes: average: 2.2 land-fall/yr

1974 hurricanes: note Carmen (#6)

…….. and 2011 is not over yet …….

Lessons to be learned:

Plan for concurrent severe weather events especially severe weather, tornadoes and flooding in the same 24-72 hour window.

Expect lingering economic and utility impacts including diminished electrical and water utility services.

What are the other impacts?

Impact to our population

1) Death/injury/stress/etc. 2) Property damage/destruction 3) Increased expenditures, changing

plans 4) Inconvenience 5) Hazardous travel

Morss, R.E., 2006: Defining “high-impact weather forecasts” in North America: Some ideas for discussion. Presentation, Workshop on North American THORPEX societal & economic research & applications, Boulder, CO.

Impact to society

1) Loss of power, water, sewers, roadways, etc.

2) reduced emergency response 3) Compromising performance/access of

hospitals, family services, etc. 4) Reduced access to necessities (food,

fuel, pharmacies, etc.) 5) Closures of schools, daycares, transit,

churches, etc. Morss, R.E., 2006: Defining “high-impact weather forecasts” in North America: Some ideas for discussion. Presentation, Workshop on North American THORPEX societal & economic research & applications, Boulder, CO.

Impact to economy

1) Reduced quality of product 2) Reduced quality of service 3) Delays 4) Increased costs 5) Loss of customers

Morss, R.E., 2006: Defining “high-impact weather forecasts” in North America: Some ideas for discussion. Presentation, Workshop on North American THORPEX societal & economic research & applications, Boulder, CO.

2011 –Setting records: a wake-up call

FEMA: Multi-hazard Mitigation Plans (2010) – what is normal? Complying with or exceeding NFIP floodplain management

regulations.

Enforcing stringent building codes, flood-proofing requirements, seismic design standards and wind-bracing requirements for new construction or repairing existing buildings.

Adopting zoning ordinances that steer development away from areas subject to flooding, storm surge or coastal erosion.

Retrofitting public buildings to withstand hurricane-strength winds or ground shaking.

Acquiring damaged homes or businesses in flood-prone areas, relocating the structures, and returning the property to open space, wetlands or recreational uses.

Building community shelters and tornado safe rooms to help protect people in their homes, public buildings and schools in hurricane- and tornado-prone areas.

FEMA: Multi-hazard Mitigation Plans (2010) – normal process

FEMA: Multi-hazard Mitigation Plans (2010) – High Impact Weather

FEMA: Multi-hazard Mitigation Plans (2010) Complying with or exceeding NFIP floodplain management

regulations.

Enforcing stringent building codes, flood-proofing requirements, seismic design standards and wind-bracing requirements for new construction or repairing existing buildings.

Adopting zoning ordinances that steer development away from areas subject to flooding, storm surge or coastal erosion.

Retrofitting public buildings to withstand hurricane-strength winds or ground shaking.

Acquiring damaged homes or businesses in flood-prone areas, relocating the structures, and returning the property to open space, wetlands or recreational uses.

Building community shelters and tornado safe rooms to help protect people in their homes, public buildings and schools in hurricane- and tornado-prone areas.

Is it enough or should we think “outside the box”?

Multi-hazard Mitigation Plans “outside the box”

Include planning for the occurrence of several sequential or concurrent high impact events: snow melt, heavy rains, winds, flooding, severe weather, hurricanes, tornadoes.

Consider all the impacts: people, services, economy, utilities’ disruption, etc.

Expect the unexpected.

Like an onion, multi-hazard plans need many layers

John F. Henz, CCM

jhenz@dewberry.comDenver CO

DewberryInnovative Solutions for

Science and Engineering

"Climate is what you expect;

weather is what you get”- Robert A. Heinlein

?Mat Mampara, PEmampara@dewberry.com

Fairfax VA

for