Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data...

38
Rip Currents--Killer Currents Jim Lushine

Transcript of Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data...

Page 1: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Rip Currents--Killer Currents Jim Lushine

Page 2: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Outline of Presentation•Rip Current Fatalities

•Data

•Forecasting

•Verification

•NWS Products

•Future Work

Page 3: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Rip Current Fatalities

Page 4: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Southeast Florida Rip Current Fatalities

0

5

10

15

20

25

1979-2003

Page 5: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Florida Rip Current Fatalities

0

10

20

30

40

1989-2003

Page 6: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Florida Weather-related Fatalities1989-2003

278

134

63

24

0

50

100

150

200

250

300

Rip Current Lightning Tornado Hurricane

Dea

ths

Page 7: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

United States Rip Current Fatalities

50

41 43

0

10

20

30

40

50

Fatalities

2001 2002 2003

Years

Storm Data

Page 8: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Weather-related Formation Factors1. Local Gradient Wind2. Swell

Page 9: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Non-Weather-related Formation Factors•Time of Low Tide*

•Persistence•Tidal Currents

•Deep Water Currents (e.g. Gulf Stream)

•Seismological Factors

•*SE Florida Coast

Page 10: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Data

Page 11: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Florida Marine Observations

Page 12: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Four Factors in Forecasting Rip Currents

Page 13: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Wind Factor

Page 14: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Gradient Wind vs Rip Current Fatalities along SE Florida Coast

05

101520253035404550

% of Time

11 12 13 14 15 16

Average Wind Speed

northeasteast northeasteasteast southeastsoutheastsouth southeast

Page 15: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Gradient Wind vs Non-Rip Current Fatalities along SE

Florida Coast

0

5

10

15

20

25

30

% of TIme

4 5 6 7 8 9 10 11

Avg Wind Speed

NNEESESSWWNW

Page 16: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Sea Breeze Effect

Page 17: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Convective Wind Initiation

Page 18: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Swell Factor

Page 19: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Swell Height* vs Rip Currents

• <2 Feet---No effect on rip currents

• 2-7 Feet---Mdt Risk of rip currents

• >7 Feet---High Risk of rip currents

• *Swell Period also important

Page 20: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Tidal Factor

Page 21: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Faster Rip Current near Low Tide

Page 22: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.
Page 23: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Tidal Variation of Fatalities

02468

10121416

No. of Fatalities

Hito1

1to2

2to3

3to4

4to5

5toLo

Loto1

1to2

2to3

3to4

4to5

5toHi

Tidal Times

1979-1988

Page 24: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Weaker Swimmers Can go Farther Offshore?

Page 25: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

PersistenceFactor

Page 26: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Days Between Initiation of Rip Currents and the First Fatality

6

19

31

37 3943

48

05

101520253035404550

Cumulative No. of

Drownings

1 2 3 4 5 6 7

Days

Page 27: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Gradient Winds vs Residual Rip Current Fatalities in SE Florida

0

10

20

30

40

50

60

% of Time

7 8 9 10

Avg Wind Speed

NNEESESSWWNW

Page 28: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Beach Patrol Rescue Reports

Page 29: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Daily Rip Current Risk1=Low2=Moderate3=High

Page 30: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Verification

0.92

0.570.62

0.58

0.370.32

0

0.10.2

0.30.4

0.50.6

0.70.8

0.91

POD FAR CSI

Rip CurrentSevere Weather

Page 31: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

NWS Rip Current-Related Products

• Surf Forecast

• Hazardous Weather Outlook

• Marine Weather Statement

• Zone Forecasts (Headlines)

Page 32: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Decision to Include in ZFP

• Weekday vs Weekend/Holiday

• Improving Weather from yesterday

• Change in surf conditions from yesterday

• Low Tide in the afternoon

Page 33: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Future Work

Page 34: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Tidal Variation of Fatalities= Hourly Rip Current Risk?

02468

101214

Fatalities

Hito1

1to2

2to3

3to4

4to5

5toLo

Loto1

1to2

2to3

3to4

4to5

5toHi

Tidal Times

1994-2003

Page 35: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Beach Geomorphology

• Renourishment

• Type of Sand

• Persistence of Rip Channels

Page 36: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Upcoming Rip Current Events

• Technical Workshop (April 6-7, 2004)

• NWS Media Event (May 24, 2004)

• FACVB meeting (June 10, 2004)

• COMET Module (Summer 2004)

Page 37: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

Florida’s Uniform Flag Warning System

Page 38: Rip Currents--Killer Currents Jim Lushine. Outline of Presentation Rip Current Fatalities Data Forecasting Verification NWS Products Future Work.

The End