messaging mesoscale snowbands and expressing uncertainty during winter weather

Maintaining Situational Awareness and

Communicating Uncertainty Associated

with Banded Snowfall

Matthew A. Dux*

Philip N. Schumacher*

Ray Wolf+

* National Weather Service – Sioux Falls, SD

+ National Weather Service – Quad Cities, IA/IL

October 21, 2015, National Weather Association

October 27, 2016 Comments or Questions: @matthewdux

Mesoscale Heavy Snow Bands

Meteorological Challenges:

- High Snowfall Gradients

- Significant Snowfall Rates

- Rapid and Unpredictable Development

- Model Ingredient Variance

NAM – 24 Hour Forecast

Actual Snowfall


Mesoscale Heavy Snow Bands

Impact Challenges

- Rapid Development of Impact

- Significant Impact to Infrastructure

- Less Planning Time by Partners

- Lack of Situational Awareness

Messaging Challenges

- Raising Awareness of Threat

- Educating on the Impact

- Prompting Action


How Do We Lower the “Surprise” Factor?

Blizzard – January 2015

Light Snow

&

50 mph winds

…Turns into This


Our Science Has Moved Forward

Ensemble Forecasting

New Smart Tools

High-Resolution Modeling

Can We Effectively

Communicate:

Potential Risk

Uncertainty

Actual Impact


Forms of Communications in 2000

Communication

methods have

grown

exponentially

over the past 16

years

2016

NWR

Text

Products

Phone/TV

Teletype


Creating a New Communication Concept

Prediction and Forecast of Heavy Mesoscale Banded Snow

Can Be Similar to That of Summer-Time Convection

Similarities:

- Conceptually Modeled Days in Advance

- Highly Depend on Mesoscale Details

- Rapidly Evolve as Event Approaches

- Share a Localized High-Impact Potential

Why Not Model the Forecast and Messaging

Process in Similar Fashions?


Proposed Communication Model

12 to 24+ Hours Ahead12 to 36+ Hours Ahead

- Focus on Potential

- Highlight Broad Area

- Preparedness Info (plant the seed)

Outlook Stage

6 to 12 Hours Ahead- Highlight Potentials

- Trend Towards Certainty

- Have Talking Points

Alert Stage

0 to 6 Hours Ahead- Prompt Action

- Mesoscale Projections

- Message IS Certain

Watch

Stage

Event Ongoing- Provide Warnings

- Continual Information

- “Now-Cast” Theme

- Show Impacts

Warning

Stage

Increased

Accuracy

&

Certainty

General

Specific

Post Event Stage

After Event-Summarize Info (partners)

-Talking Points (staff)


Experimental Probabilistic Snow Products

1-2 in. 2-4 in. 4-6 in.

Expected snowfall

6-10 in. 10-15+ in.

Observed snowfall

Mitchell 6” Less than 1”

Sioux Falls 10” 3”

Spencer, IA 2” 10”

Worthington 8” 1”

Yankton 1” 5”

Probabilistic Snowfall Provides Us A Way To Communicate This Uncertainty.

Current Forecast If the Forecast is 25 Miles Off


“Setting the Ceiling & the Floor”

3.) While popular with EMs and DOTs, some

in the public felt this graphic was a “dodge”

to avoid committing to any snowfall amount.

1.) Combo of WFO Forecast and

Ensemble Spreads

2.) Provides information on the

“worst case scenario”.


“Focus on the Baseline & Leave Room”

Uses similar and risk

levels to words already

associated with severe

weather.

Can focus more on

critical snowfall

thresholds.

Sets a floor for snowfall

rather than a ceiling.

We believe this may

reduce hype as well by

avoiding talk of

extreme snowfall

amounts.Graphics created from Probability of Exceedance grids using

the SAC Grid Image Maker. WFO SLC provided the code.


Example Case

Typical Mid-Winter Snow

Event for Northern Plains

Expectations of

Widespread Light Snow

3” or Less

Arrival of Snow Late

Afternoon/Evening

Models Showing Signs of

Banded Precipitation36 Hour Snow Forecast

Timeline: 36 Hours in Advance


Outlook Stage Timeline: 12 to 36 Hours Prior

Forecast Awareness

- Be Aware of Model

Trends

- Address Concerns in

the AFD

- WWA in Effect?

Event Messaging

- Focus on Potential

- Highlight Broad Area

- Address Uncertainty

Slight

Slight


Outlook Stage Timeline: 12 to 36 Hours Prior


Alert Stage Timeline: 6 to 12 Hours Prior

Forecast Awareness- In Depth Examination

of Environment

- Use Probabilities to

Inspect Heavy Snow

Potential

- Change in Headlines

Needed?

- Adjust Staffing?

Event Messaging- Narrow Down Risk of

Heavy Snow Area

- Begin to Stress

Potential Impacts

- Address Uncertainty

Slight

Slight

Slight



Messaging Plan

- Future Radars

- Impact Potentials

-Event Timing

Other Thoughts:- Invite Media In

- Dedicated

Communicator?

- Skype Interviews

- 30 Sec Updates


Watch Stage Timeline: 0 to 6 Hours Prior

Forecast Awareness- Heavy Focus on

Observations

- Begin Mesoscale

Interrogation

- Write a Mesoscale

Discussion in AFD

- Headline/Staffing

Changes?

Event Messaging- Narrow Risk of

Heavy Snow Area

- Begin to Stress

Potential Impacts

- Change Tone of

Message


Watch Stage Timeline: 0 to 6 Hours Prior

Messaging Plan

- Hazard Education

- Prompt Action Plans

- Show Potential

Other Thoughts:- Change Tone of

Message

- Communicator in

Place

- WWOP Active?


Warning Stage Timeline: Event Ongoing

Forecast Awareness

- Focusing on Incoming

Information

- Gather Reports

- Continual Weather

Watch and Forecast

Adjustments

- Warning Already

Issued

- Staffing Adjusted

Strong Emphasis on

Social Media and

Communications


Warning Stage Timeline: Event Ongoing

What Types of Messages:

- Live Traffic Cameras

- 30 Second Human Video Updates

- Animated Radar GIFS to Show Motion

- Showing Impacts/Snow Data

Event Messaging

- Heavy Focus on Impacts

- Continual Flow of Information

- Express Certainty in the Message

- Provide Outlooks into the Night


Post Event Stage Timeline: Event Ongoing

Messaging Plan

- Continual Information

- Web Page Summary

- Show Impacts

-Provide Support for

RecoveryOther Thoughts:

- Key Event Points for all

Staff Members

- Control Message

- PIO/Communicator


What Tools Have Helped Us…

A Robust Set of Graphics Templates

Specialized Communications Training For

All Staff Members

-expressing probabilities

-briefing on impacts

Keep the Key Messages Visible

To All Staff Members


What Are Our Limitations?

Various skillset levels in graphics and

communications

Lack of time or human resources available

Forecaster-to-forecaster and event-to-

event inconsistency


Important Questions for the Future

How Do We Advertise the Worst Case Snow Scenario? Can We?

How Do You Message Extreme Events Without Leading to “Forecast Hype”?

Does “One-Size-Fits-All” Messaging Work? Does Message Need to Vary by

User (Public/Schools/Emergency Management/DOT)?

Contact: [email protected]

@MatthewDux