Communicating Societal Impacts An Objective Methodology WDTB Winter Weather Workshop October 9, 2002

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CommunicatingSocietal Impacts--- An Objective
MethodologyWDTB Winter Weather
WorkshopOctober 9, 2002
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The Challenge

• Do Similar Storms Produce Different Impacts on
  the Public?
• Can We Develop a Set of Criteria so the
  Forecasters Can Objectively Evaluate Potential
  Impacts?
• How Can We Communicate the Potential Impacts to
  the Public?

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Winter Storm Event C
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(No Transcript)
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Buffalos Greatest 24-hour Snowfalls

• Dec 9-10, 1995 37.9 inches
• Jan 10-11, 1982 25.3 inches
• Nov 20, 2000 24.9 inches
• Dec 15-16, 1945 24.3 inches
• Nov 30/Dec 1, 79 20.1 inches

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Monday 4AM Forecast

• NYZ010-011-201635-ERIE-GENESEE-INCLUDING THE
  CITIES OF...BATAVIA...BUFFALO435 AM EST MON NOV
  20 2000
• ...LAKE EFFECT SNOW WARNING THIS AFTERNOON AND
  TONIGHT...
• .TODAY...SNOW DEVELOPING THIS MORNING...THEN A
  BAND OF HEAVIER LAKE EFFECT SNOW WILL MOVE SOUTH
  INTO THE AREA LATER THIS AFTERNOON. ACCUMULATION
  OF 2 TO 4 INCHES LIKELY BY RUSH HOUR ACROSS
  NORTHERN ERIE AND GENESEE COUNTIES. HIGH ABOUT
  35. SOUTH WINDS 10 TO 15 MPH BECOMING SOUTHWEST
  15 TO 25 MPH.
• .TONIGHT...BLUSTERY WITH LAKE EFFECT SNOW
  PRODUCING TOTAL ACCUMULATION OF 6 TO 8 INCHES
  BEFORE MOVING SOUTH OF THE REGION BY MORNING.
  LOW IN THE MID 20S. SOUTHWEST WINDS 20 TO 30 MPH
  CAUSING BLOWING AND DRIFTING SNOW. CHANCE OF
  SNOW 100 PERCENT.
• .TUESDAY...CONTINUED BLUSTERY WITH SNOW LIKELY.
  HIGH NEAR 30. CHANCE OF SNOW 80 PERCENT.

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Effects of Chestnut Storm

• Buffalo Airport Closed 24 Hours
• All Roads Closed Including NY Thruway
• Thousands stranded.. Including over 2500 school
  children
• Power Outages Affecting 10,000

• Activation of 200 National Guard
• Gov Pataki Declares State of Emergency
• 43.5 Million in Overall Damage in West NY (20M
  Erie Co)
• Postponement of Sabres/Flyers Games

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Are All Major Lake Effect Storms Alike?
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Similarities Between Gary and Chestnut

• States of Emergency Declared
• Buffalo International Airport Closed Down
• New York State Thruway Closed
• Buffalo Sabres Games Postponed

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Theres More to a Warning Than The Amount
Total Snowfall
Clean up Costs (in Millions)
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Theres More to a Warning Than The Amount
Total Snowfall
Days of Cleanup
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Theres More to a Warning Than The Amount
Total Snowfall
Number Stranded Schoolchildren
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Gary Occurred During a WEEKEND
Chestnut Occurred on the FIRST DAY of the
WORKWEEK at Rush Hour.

• Timing of this storm was CRITICAL !!!

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Chestnut Struck With Perfect Timing
Rush hour
Hourly Snowfall
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Major Winter Storms Have to be Handled
Individually

• One 24 Snowstorm May Be Totally Different From
  Another 24 event
• Must be Able to Highlight IMPACT POTENTIAL
• The Forecaster Must Assess Societal Impacts

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Assessing Societal ImpactsAn Objective Approach

• Timing of the Storm
  (Day of Week / Time of day)
• Seasonality
• Type of Snow
• Post Storm Conditions

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Assessing Societal Impacts

• Timing of the Storm
  (Day of Week / Time of day)
• Seasonality
• Type of Snow
• Post Storm Conditions

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Time of Day / Day of Week
Weekend 7 AM to 4 PM Some activity, church,
shopping, events (2) 4 AM to 7 AM Very little
activity (1) Weekday 9 PM to 5 AM Little
activity, removal crews good progress (1) 5 AM
to 7 AM Decisions made by officials, increased
traffic (4) 7 AM to 9 AM Rush hour (5) 9 AM
to Noon Reduced Activity. School dismissal
decisions? (3) Noon to 4 PM Work / School
Dismissal Decisions (4) 4 PM to 6 PM Evening
Rush Hour (5) 6 PM to 9 PM Evening
activities, sports, restaurants, etc (2 to 4)
Monday Prior To 5 PM (3)
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Communicating Societal Impacts

• Timing of the Storm
  (Day of Week / Time of day)
• Seasonality
• Type of Snow
• Post Storm Conditions

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Seasonality

• First major snow of the season (5)
• First storm after a long thaw (4)
• Mid season storm during a period of sub freezing
  weather and daily light snows (2)
• Late season, fast melting, warm ground (2 or 3)

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Communicating Societal Impacts

• Timing of the Storm
  (Day of Week / Time of day)
• Seasonality
• Type of Snow
• Post Storm Conditions

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Type of Snow

• Wet (3 to 5) difficult in driving and removing
  but easier to treat chemically due to temps roof
  collapses heart attack snow
• Fluffy (1 to 3) ease in removal more difficult
  to treat greasy driving
• Windy (3,4) drifting visibility problems,
  (especially with dry fluffy snow)

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Communicating Societal Impacts

• Timing of the Storm
  (Day of Week / Time of day)
• Seasonality
• Type of Snow
• Post Storm Conditions

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Post Storm Conditions

• Sub freezing, wintry Snow to hang around and
  pile up (4-5 early-mid winter, 3 late)
• Mild, above freezing long term Snow will melt
  off or diminish in a few days (2)
• Mild, short term Snow to change to
  rain (1 or 2) but (3-4 if changing to IP/ZR)

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Actual Warning - Generic
Urgent - Winter Weather Message National Weather
Service Buffalo NY 445 AM EST Mon Nov 20 2000
...Plowable Snowfall Expected for Parts of
Western New York Today... .A Compact Low
Pressure System near Lake Huron this Morning Will
Track Just to the North of the Region Tonight and
Tuesday and this Will Result in a Widespread
Snowfall with Bands of Lake Effect Snow
Developing Downwind of Lakes Erie and Ontario.
As the Storm System Approaches the Region this
Morning a General Snowfall Will Develop over the
Far Western Counties. The Snowfall Will Become
Lake Enhanced over Parts of the Niagara Frontier
by Midday While Light Snow Will Spread Across the
Finger Lakes and over Sites East of Lake Ontario.
Most Areas Will Receive a Couple Inches of Snow
by Nightfall...With as Much as 6 Inches of Snow
Possible over Parts of the Niagara Frontier.
Tonight...
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Value Added Information
URGENT - WINTER WEATHER MESSAGE NATIONAL WEATHER
SERVICE BUFFALO NY 445 AM EST MON NOV 20 2000
...Plowable Snowfall Expected for Parts of
Western New York Today... .A Compact Low
Pressure System near Lake Huron this Morning Will
Track Just to the North of the Region Tonight and
Tuesday and this Will Result in a Widespread
Snowfall with Bands of Lake Effect Snow
Developing Downwind of Lakes Erie and Ontario.
As the Storm System Approaches the Region this
Morning...a General Snowfall Will Develop over
the Far Western Counties. The snowfall will
Become Lake Enhanced over Parts of the Niagara
Frontier by Midday While Light Snow Will Spread
Across the Finger Lakes and over Sites East of
Lake Ontario. By mid afternoon a band of heavy
lake effect snow will develop over the northern
suburbs of Buffalo. This band of heavy snow will
shift south through the metropolitan area later
this afternoon and evening...which will greatly
impact this evenings rush hour.
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NYZ010-011-201623- ERIE NY-GENESEE NY- INCLUDING
THE CITIES OF...BUFFALO NY...BATAVIA NY ...Lake
Effect Snow Warning For This Afternoon And
Tonight... A General Snowfall Will Develop This
Morning And Produce Accumulations of 2 to 3
Inches By Nightfall. This Snowfall Will Be
Accompanied by a Band of Heavier Lake Effect Snow
That Will Develop to The North of Buffalo Early
This The Afternoon. This Band of Heavy Lake
Effect Snow Is Expected to Slowly Drift to The
South Across Genesee And North Central Erie
County Later This Afternoon And Evening...Where
Accumulations of up to 6 Inches Are Possible by
Nightfall. The Steadiest And Heaviest Snow For
The Buffalo Metropolitan Area Is Expected to Fall
Between 2 and 6 PM. Commuters During This
Evenings Rush Hour Will Likely Experience Very
Difficult Driving Conditions. Snowfall Rates of
an Inch or Two an Hour, Combined with a Heavy
Volume of Traffic, Could Clog Many of the Major
Arteries Around The Metropolitan Area. Motorists
Should Be Prepared For a Slow and Difficult
Evening Commute.
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Addressing Societal Impacts

• If any of the impact criteria are ranked at a
  category 4 or 5 by the consensus forecast
• Then include a specific impact statement within
  the watch/warning.
• Will allow officials to delineate between typical
  and high-impact storms.

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Communicating Societal Impacts

• Alerts Planning Officials To Critical Situations
• Give School/Town Officials Time to Plan
• Highlight Storms That Could Produce Emergency
  Situations From Those That Wont