scott prosise tim holley

Scott Prosise Tim Holley

2012 Hurricane Season

Ocean Prediction Center

OPC Support for NHC…extratropical guidance

• OPC will provide a forecast for location, maximum sustained winds and maximum extent of these winds in each quadrant for overwater extratropical cyclones N of 25N.

• Provide estimated time of full transition from tropical cyclone to extratropical.

• Provide a brief discussion, via email of forecast reasoning for the above forecast

• Radius of 12 ft seas north of 31N

Tropical Systems in 2012

• Tropical Storm Alberto

• Tropical Storm Beryl• Hurricane Chris• Tropical Storm Debby• Hurricane Gordon• Hurricane Kirk

OPC provided extratropical/post-tropical guidance for 12 of 19 tropical cyclones

• Hurricane Leslie• Hurricane Michael• Hurricane Nadine• Hurricane Rafael• Hurricane Sandy• Tropical Storm Tony

Forecast Issued

YEAR NUMBER OF TROPICAL CYCLONES

2012 176 Advisories

467 Extratropical forecast points

( 113 or 24% for Nadine )

2011 185 Extratropical forecast points

2003 2004 2005 2006 2007 2008 2009 2010 2011 20120

20

40

60

80

100

120

miles

24 Hour Forecast Error

48 Hour Forecast Error

2003 2004 2005 2006 2007 2008 2009 2010 2011 20120

20

40

60

80

100

120

140

160

180

200

Miles

72 Hour Forecast Error

2003 2004 2005 2006 2007 2008 2009 2010 2011 20120

50

100

150

200

250

300

Miles

96 Hour Forecast Error

2003 2004 2005 2006 2007 2008 2009 2010 2011 20120

50

100

150

200

250

300

350

Miles

120 Hour Forecast Error

2003 2004 2005 2006 2007 2008 2009 2010 2011 20120

100

200

300

400

500

600

Miles

OPC VERIFICATION

• Still done manually. Slow and labor intensive.

• Intensity forecast…– Slightly under forecast (< 5 kt) 24 and 48

hours– Slightly over forecast (< 5 kt) 96 and 120

hours– 27 forecast were exact (zero error)

Sep 8 - 500 MB analysis and 96 hr forecast

Leslie

Leslie – Verification killer! 120 hour forecast error = 1209 NM

Extratropical Life

• Longest life: Chris - 4.25 days • Shortest life: Kirk – Instant dissipate• Landfall:

– Leslie – Iceland– Rafael – Portugal– Sandy - USA

T.S Alberto

T.S. Beryl

T.S. Beryl

Hurricane Chris

Hurricane Chris

T.S. Debby

T.S. Debby

Hurricane Gordon

Hurricane Gordon

Hurricane Kirk

Hurricane Kirk

Hurricane Leslie

Hurricane Leslie

Hurricane Michael

Hurricane Michael

Hurricane Nadine

Hurricane Nadine

Hurricane Rafael

Hurricane Rafael

POST-TROPICAL RAFAEL OCT 18 03Z

Hurricane Sandy

Hurricane Sandy

Hurricane Sandy

47 ft seas 21Z - 10/29/12

Hurricane Sandy

NPP VIIRS Day – Night Band 10/29/12

Hurricane Tony

Hurricane Tony

2012 Extratropical Post-Tropical Track Composite

Problems?

• No significant problems noted in 2012• Work flow i.e. extratropical forecast

responsibility more divided.• Three desks, Atlantic Regional, High Seas

and Outlook desk all issue tropical forecast

The End Thank You

Scott Prosise

Ocean Prediction Center

2013 NOAA Hurricane Conference