1. Jason Runyen
Senior Forecaster
NWS Corpus Christi
Looking Beyond the Category

2. Tropical Cyclone Hazards
Hazards Differ from Storm to Storm
Storm Surge Flooding Tornadoes
Flooding RainsDamaging Winds

3. Category 1-min. Sustained Winds
(mph)
Storm Examples Wind Impacts
Tropical
Depression
Less than 39 mph Relatively minor
Tropical
Storm
Between 39 and 73 Allison Can be significant
1 74 - 95 Jerry 1989 Very dangerous; will produce
Claudette 2003 some damage
Humberto 2007
2 96 - 110 Georges 1998
Ike 2008
Extremely dangerous; will
produce extensive damage
3 111 - 130 Alicia 1983 Devastating damage
Katrina 2005
Rita 2005
4 131 - 155 1900 - Galveston Catastrophic damage
Carla 1961
5 > 156 Andrew 1992 Catastrophic damage
Camille 1969
Saffir-Simpson Hurricane Wind Scale

4. • The maximum sustained wind in the storm
• A measure of the degree of damage
possible in areas that experience the
maximum wind (typically the eyewall)
• Link with outline of wind impacts expected
with each rating:
http://www.nhc.noaa.gov/aboutsshws.php
What the SSHWS Indicates

5. What the SSHWS Does Not Indicate
• The size of the wind field/the area impacted
• The magnitude of the storm surge; scale is
related but other factors are important
• The amount of rain that will fall and the
associated flood threat
• Whether the storm will be big tornado
producer
NOT an overall indicator of the severity of the storm
(although often interpreted that way)
What the SSHWS Does NOT Indicates

6. Storm Surge
Damaging
Winds
Tornadoes Inland
Flooding

7. Hurricane Categories
Saffir-Simpson Hurricane Wind Scale

8. Rapid Intensification before landfall – Winds 125 with gusts to 175 at landfall
Hurricane Celia – Category 3

9. Celia Wind Impacts

10. Celia Wind Impacts

11. LARGE - FLOYD, 1999 SMALL - ANDREW, 1992
...but both were at the same intensity of 140 kt!
Variability in Hurricane Size

12. Sustained winds of 160 mph at landfall – with gusts to 200 mph
Hurricane Andrew – Category 5

13. Andrew Wind Impacts

14. Cat 5 SmallCat 2 Large
Moderate Damage and Power Loss
over a Large Area
Catastrophic Damage over a Small Area

15. Hurricane Carla - 1961

16. Tropical
Storm Force
Winds
Hurr
Force
Winds

17. Tropical Storm Hermine

19. Robstown

20. Bishop

21. Bishop

22. Storm Surge
Damaging
Winds
Tornadoes Inland
Flooding

23. Historically the most deadly hazard associated with hurricanes
Storm Surge

24. Bringing it all Together – Total Water

25. Surge Dependence on Size: All runs
simulate a cat 4 but with different size

26. Debunking the Category Myth
Cat . 4
Charley: 7 ft
Cat . 3
Katrina: 27 ft
Cat . 2
Ike:14 to 18 ft
Cat . 1
Sandy: 13 ft

27. Sandy
Katrina
940 miles
415 miles
Size Comparison

28. Ike (2008) / Humberto (2007) Comparison
An Extreme Size Difference

29. Historical Storm Surge
Events for Texas
Carla - 1961
Texas Record
22.8 Feet

30. Historical Storm Surge
Events for Texas
Hurricane Ike - 2008
15-20 Feet

31. Historical Storm Surge
Events for Texas
Galveston - 1900
15 Feet

32. Historical Storm Surge
Events for Texas
Corpus Christi - 1919
16 Feet

33. Storm Surge
Damaging
Winds
Tornadoes Inland
Flooding

34. 34
1921
Hurricane
36”
Hurricane
Alice 1954
35”
Hurricane
Beulah 1967
30”
T.S. Amelia
1978
48”
Flood
1998
30”
T.S. Claudette
1979
43”
T.S. Allison
2001
40”
T.S.
Charlie 1998
18”
Hurricane
Alex 2010
20+”
Flood
2002
30”
Historical Texas Floods from Tropical Systems

36. • 25-30” Rainfall
• Record Flooding in Live Oak
County
• Nueces River Crested Three
Rivers 49.21 ft Calallen 16
ft.
• Cat 4 at landfall
• $200 Million Damage
• 10 Killed
Hurricane Beulah - 1967

37. Tropical Storm Allison Path
in Texas

38. 38
Houston, TX
T.S. Allison 2001
$5.5 Billion, 41 Fatalities
Tropical Storm Allison - 2001

39. Tropical Storm Allison
June 2001

40. Hurricane Alex - 2010

41. Storm Surge
Damaging
Winds
Tornadoes Inland
Flooding

42. • North and Northeast moving hurricanes
produce most tornadoes.
• Nearly 30% develop before the tropical
cyclone center reaches the coastline
• 70% occur over land.
• More than 90% of tornadoes occur in the
right front quadrant (relative to the storm
motion) of a tropical cyclone
• Small and low-topped
• Usually during the daytime
Tornado Characteristics in Tropical Cyclones

43. Rank Name Year Tornadoes Waterspouts
1 Hurricane Ivan 2004 127 4
2 Hurricane Beulah 1967 115
3 Hurricane Frances 2004 106
4 Hurricane Rita 2005 92
5 Hurricane Andrew 1992 61 2
6 Hurricane Katrina 2005 58 3
7 Tropical Storm Fay 2008 49
8 Hurricane Georges 1998 48 9
9 Hurricane Gilbert 1988 47
10 Hurricane Cindy 2005 44
11 Hurricane Jeanne 2004 42 1
12 Hurricane Danny 1985 39
13 Tropical Storm Beryl 1994 37
14 tie Hurricane David (tie) 1979 34
14 tie Tropical Storm Bill (tie) 2003 34
16 Hurricane Ike 2008 33
17 tie Hurricane Agnes 1972 32
17 tie Hurricane Isaac 2012 32
19 Hurricane Opal 1995 31
20 tie Hurricane Allen 1980 29
20 tie Tropical Storm Lee 2011 29 1
22 Hurricane Gustav 2008 28
23 Tropical Storm Allison 2001 28 3
24 Tropical Storm Josephine 1996 27 1
25 Hurricane Lili 2002 27
26 Tropical Storm Debby 2012 25 3
27 Hurricane Charley 2004 24 1
28 Hurricane Alicia 1983 22
29 Hurricane Audrey 1957 21
30 tie Hurricane Carla (tie) 1961 20
30 tie Hurricane Gaston (tie) 2004 20 1
Tropical Cyclone
Rankings for Number
of Tornadoes
Produced
McCaul, Grazulis
http://www.tornadoproject.com/alltorns/tophurricanes.htm

45. • Greatest Number of
Tornadoes occurred in
the Northeast Quadrant
over the Coastal Bend
Region.
Held Record 115
Tornadoes until
Hurricane Ivan
Hurricane Beulah - 1967

46. Photo: Washington Times
Record 127
Tornadoes!
Hurricane Ivan - 2004

47.  Storm produced 35
tornadoes
 10 significant (F2>)
Located 150-250 miles
from storm center
Hurricane Allen - 1980

48.  Total of 41 tornadoes
 Occurred at distances of
230-470 miles from the
storm center that was
near Monterrey, Mexico
 F2 tornadoes in Del Rio
and San Antonio
Hurricane Gilbert -1988

49. Tropical Cyclone Hazard Impacts
Dependence on Category of Storm (Saffir Simpson Hurricane Wind Scale)
Storm Surge Flooding Tornadoes
Flooding RainsDamaging Winds
Not RelatedOnly Somewhat Related
Not RelatedRelated although not whole story
~

50. Error Cone ~ Cone of Uncertainty
What Does the Cone Tell Us
• NHC Forecast of where the CENTER
of the storm will be in 12, 24, 36,
48, 72, 96, 120 hours
• 5 Year NHC Forecast error (2/3rds
of tropical cyclone center forecasts
remain in cone)

51. Error Cone ~ Cone of Uncertainty
What Does the Cone NOT Tell Us
• How far out the tropical storm/hurricane force winds will
extend
• Timing of the onset of tropical storm/hurricane force
winds
• How high the storm surge will be
• How far out the storm surge will extend
• Onset of when flooding from storm surge will begin
• How much rainfall is expected
• Where and how far out flooding rain is expected
• When the rain will begin and end
• Where tornadoes are expected
• When the tornado threat may begin
• 1/3rd of the time the NHC forecast goes OUT of the cone
• Forecast CONFIDENCE
• Range of scenarios
Error Cone like the SSHWS
does NOT tell the whole story!

52. Hurricane Isaac (min cat 1)
6 to 12 feet of Storm Surge; levees
topped, extensive flooding
Up to 20 inches of rain
Case Examples & Testimonials

55. Parish President: “Worse
than Katrina” (Katrina Cat 3
at landfall, Isaac barely a
category 1)

56. Hurricane Isaac Makes Landfall in Louisiana – NYTimes.com
August 28, 2012
Federal officials warned again and again that the storm, which killed
29 people in Haiti and the Dominican Republic, would generate high
seas, intense rain and serious flooding in coastal and inland areas for
days.
But residents toughened by Hurricane Katrina, which tossed floating
casinos across the highway, saw Isaac as more a curiosity and a
nuisance than a major threat. “If it’s a 1 or a 2, most people don’t flip
out,” said Claire Parker, 23.
• Overreliance on category and comparison with
previous storm (Katrina)
• Many times people focus and make decisions
based on the category alone, without digging
into the details!

57. Hurricane/Superstorm Sandy:
HurricaneHybrid; Another very
large low category (1) storm with
huge impact

58. Officials fear many won't evacuate for Hurricane Sandy
USA Today, October 28th 2012
The problem is, some people in the storm's path evacuated for
Hurricane Irene last year only to be met by more punishing winds
and floods further inland. This year, many of them are staying put.
"There are a lot of folks out there who feel if it's not a Category 3
or higher, they tend to dismiss it," says Julia Jarema of the North
Carolina Division of Emergency Management. "Hurricane Sandy is
a huge storm. We want them to take it seriously."
• Overreliance on category and comparison with
previous storm (Irene)

59. Approximately 2/3 of fatalities due
to Surge and 1/3 Due to Winds
Hurricane Sandy - 2012

60. Hurricane Ike: Large Category 2 Storm

61. Quotes from “Storm Surge
and Certain Death: Interviews
with Texas Coastal Residents
Following Hurricane Ike,”
Weather Climate and Society
Morss and Hayden (2010)
1
2
3

62. Conveying All Threats – Not the Category
• Hurricane Local Statements
• Tropical Cyclone Potential Impact Graphics
• Email Briefings & Social Media Posts
• Storm Surge Warnings – Possibly 2014
• Better Inundation Graphics - 2015

63. Alternative to SSHWS
Hurricane Local Statements from Weather Forecast
Offices
• Detailed forecast for each hazard (wind, rain,
storm surge flooding, wind) spelled out for
each county
• Forecast uncertainty described
• Attempt to put new and the most important
information at the top of the product (no
more burying the lead)
• This text product can be long

64. ...WINDS...
AS TROPICAL STORM ISAAC APPROACHES...SUSTAINED TROPICAL STORM
FORCE WINDS ARE EXPECTED TO BEGIN THIS MORNING. HURRICANE FORCE WINDS
WILL BE POSSIBLE TONIGHT. MAXIMUM WINDS ARE FORECAST TO BE IN THE
60 TO 80 MPH RANGE WITH GUSTS TO 95 MPH.
...STORM SURGE AND STORM TIDE...
AS TROPICAL STORM ISAAC APPROACHES THE COAST...THERE IS AN
INCREASING CHANCE FOR COMBINED STORM SURGE AND ASTRONOMICAL TIDE
WATERS UP TO 12 FEET ABOVE MEAN SEA LEVEL WITHIN AREAS CLOSER TO
THE COAST...RESULTING IN WORST CASE FLOOD INUNDATION OF 10 TO 12 FEET
ABOVE GROUND LEVEL MAINLY IN AREAS OUTSIDE HURRICANE PROTECTION
LEVEES ESPECIALLY IN ST BERNARD PARISH. STORM SURGE FLOODING SHOULD
BEGIN EARLY TUESDAY MORNING AND CONTINUE THROUGHOUT TUESDAY AND
TUESDAY NIGHT.
...INLAND FLOODING...
A FLASH FLOOD WATCH IS IN EFFECT FOR THE ENTIRE AREA. SEE LATEST
FORECAST FOR LATEST INFORMATION. LISTEN FOR POSSIBLE FLOOD
WARNINGS FOR YOUR LOCATION...AND BE READY TO ACT IF FLOODING
RAINS OCCUR. EXPECT STORM TOTAL RAINFALL OF 8 TO 12 INCHES OF
WITH LOCALLY HIGHER AMOUNTS POSSIBLE.
...TORNADOES...
ISOLATED TORNADOES WILL BE POSSIBLE AS RAIN BANDS ASSOCIATED WITH
TROPICAL STORM ISAAC MOVE ACROSS THE AREA TODAY AND WEDNESDAY.
Hurricane Local Statement 5 am August 28th, NWS New Orleans
Wind timing and
magnitude
Storm tide
referenced to
height above sea
level AND height
above ground level
Rainfall information
and flood threat
described
Tornado threat
described

65. Alternative to SSHWS
Tropical Cyclone Potential Impact Graphics
• Graphical depiction of potential threat for each
tropical cyclone hazard
• Threat rated none, low, moderate, high, extreme
with each term defined in a legend
• Issued whenever watches or warnings are out for
an area (48 hours prior to arrival of TS force
winds)
• Starting point for these graphics is derived from a
set of tools that translate existing forecast
guidance

66. http://www.weather.gov/tcig
http://w1.weather.gov/tcig

69. WFO New Orleans Coastal Flooding
Impact Graphics Definitions (Storm
Surge)

70. Can Create KML Images/Google Earth

71. Can Create KML Images/Google Earth

73. Slow Moving TS, >20 inches of rain in
some spots!

74. FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE TALLAHASSEE FL
1016 PM EDT MON JUN 25 2012
FLC037-077-129-260315-
/O.CON.KTAE.FF.W.0016.000000T0000Z-120626T0315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
LIBERTY FL-WAKULLA FL-FRANKLIN FL-
1016 PM EDT MON JUN 25 2012
...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1115 PM EDT FOR
NORTHEASTERN FRANKLIN...WAKULLA AND SOUTHEASTERN LIBERTY COUNTIES...
...A FLASH FLOOD EMERGENCY CONTINUES FOR WAKULLA COUNTY...
AT 1007 PM EDT...EXTREME FLASH FLOODING CONTINUES ACROSS WAKULLA
COUNTY...PARTICULARLY ALONG THE SOPCHOPPY RIVER INCLUDING THE TOWN
OF SOPCHOPPY. WATER HAS ALREADY ENTERED HOMES IN SOPCHOPPY AND THE
SOPCHOPPY RIVER IS EXPECTED TO CREST FAR ABOVE ITS PREVIOUS RECORD
CREST.
THIS IS A LIFE THREATENING SITUATION AND MANY AREAS THAT HAVE NOT
FLOODED IN RECENT MEMORY WILL FLOOD TONIGHT.
&&

76. Conclusions
• Need to dig deeper than the Saffir-Simpson Hurricane
Wind Scale if we are to anticipate hurricane threats
• Public education is a challenge
• NWS Forecast Offices make detailed forecasts of each
hazard in their Hurricane Local Statements
• Tropical Cyclone Potential Impact Graphics are intended to
take probability into account, represent potential
outcomes that require preparation.
• Hurricane Center Public Advisories are a great source of
information on the larger scale
• Storm surge warning coming down the pike also intended
to alert people to risk of surge

77. Jason Runyen
Jason.Runyen@noaa.gov
361-289-0959
Senior Forecaster - NWS Corpus Christi
Thank You!
Have a Safe 2013 Hurricane Season