Winter 2016-17 SWOP Conference Call SWOP... · 2016-12-12 · Blue color in the Equatorial Pacific...
Transcript of Winter 2016-17 SWOP Conference Call SWOP... · 2016-12-12 · Blue color in the Equatorial Pacific...
![Page 1: Winter 2016-17 SWOP Conference Call SWOP... · 2016-12-12 · Blue color in the Equatorial Pacific shows water temps 1-2 degrees Celsius below normal since mid-August . La Nina Winter](https://reader034.fdocuments.net/reader034/viewer/2022050103/5f4263866e8d8d0758738077/html5/thumbnails/1.jpg)
Winter 2016-17
SWOP Conference Call
Matt Barnes
Scott Baker
![Page 2: Winter 2016-17 SWOP Conference Call SWOP... · 2016-12-12 · Blue color in the Equatorial Pacific shows water temps 1-2 degrees Celsius below normal since mid-August . La Nina Winter](https://reader034.fdocuments.net/reader034/viewer/2022050103/5f4263866e8d8d0758738077/html5/thumbnails/2.jpg)
Winter 2016-17 Outlook
Updated: November 17
No
clear
temp
trend
![Page 3: Winter 2016-17 SWOP Conference Call SWOP... · 2016-12-12 · Blue color in the Equatorial Pacific shows water temps 1-2 degrees Celsius below normal since mid-August . La Nina Winter](https://reader034.fdocuments.net/reader034/viewer/2022050103/5f4263866e8d8d0758738077/html5/thumbnails/3.jpg)
Winter 2016-17 Outlook
Updated: November 17
Slight
trend
toward
above
normal precip
![Page 4: Winter 2016-17 SWOP Conference Call SWOP... · 2016-12-12 · Blue color in the Equatorial Pacific shows water temps 1-2 degrees Celsius below normal since mid-August . La Nina Winter](https://reader034.fdocuments.net/reader034/viewer/2022050103/5f4263866e8d8d0758738077/html5/thumbnails/4.jpg)
Science Behind the Outlook
• El Nino Southern Oscillation (ENSO) sea surface temperature anomalies in the equatorial Pacific off the coast of Peru/Ecuador
Warmer than normal water: El Nino phase
Cooler than normal water: La Nina phase
• Arctic Oscillation pressure difference between the Arctic and 45N latitude
• North Atlantic Oscillation pressure difference across the north Atlantic between Iceland and the Azores
![Page 5: Winter 2016-17 SWOP Conference Call SWOP... · 2016-12-12 · Blue color in the Equatorial Pacific shows water temps 1-2 degrees Celsius below normal since mid-August . La Nina Winter](https://reader034.fdocuments.net/reader034/viewer/2022050103/5f4263866e8d8d0758738077/html5/thumbnails/5.jpg)
ENSO Neutral Conditions
![Page 6: Winter 2016-17 SWOP Conference Call SWOP... · 2016-12-12 · Blue color in the Equatorial Pacific shows water temps 1-2 degrees Celsius below normal since mid-August . La Nina Winter](https://reader034.fdocuments.net/reader034/viewer/2022050103/5f4263866e8d8d0758738077/html5/thumbnails/6.jpg)
La Nina Phase
H L
Strong upwelling brings cold deep ocean water to the surface
![Page 7: Winter 2016-17 SWOP Conference Call SWOP... · 2016-12-12 · Blue color in the Equatorial Pacific shows water temps 1-2 degrees Celsius below normal since mid-August . La Nina Winter](https://reader034.fdocuments.net/reader034/viewer/2022050103/5f4263866e8d8d0758738077/html5/thumbnails/7.jpg)
Current La Nina Conditions
Blue color in the Equatorial Pacific shows water temps
1-2 degrees Celsius below normal since mid-August
![Page 8: Winter 2016-17 SWOP Conference Call SWOP... · 2016-12-12 · Blue color in the Equatorial Pacific shows water temps 1-2 degrees Celsius below normal since mid-August . La Nina Winter](https://reader034.fdocuments.net/reader034/viewer/2022050103/5f4263866e8d8d0758738077/html5/thumbnails/8.jpg)
La Nina Winter Pattern
No Strong Temp/Precip Correlation for Central Illinois
![Page 9: Winter 2016-17 SWOP Conference Call SWOP... · 2016-12-12 · Blue color in the Equatorial Pacific shows water temps 1-2 degrees Celsius below normal since mid-August . La Nina Winter](https://reader034.fdocuments.net/reader034/viewer/2022050103/5f4263866e8d8d0758738077/html5/thumbnails/9.jpg)
Better Indicators for Illinois
Arctic Oscillation (AO) and North
Atlantic Oscillation (NAO)
• Good for short-term forecasting, but
predictability decreases after 1-2
weeks
• Key factor in the CPC 6-10 day
outlooks
![Page 10: Winter 2016-17 SWOP Conference Call SWOP... · 2016-12-12 · Blue color in the Equatorial Pacific shows water temps 1-2 degrees Celsius below normal since mid-August . La Nina Winter](https://reader034.fdocuments.net/reader034/viewer/2022050103/5f4263866e8d8d0758738077/html5/thumbnails/10.jpg)
Arctic Oscillation
Mean pressure difference between the
Arctic and 45N latitude
• Negative phase: Higher pressure in
the Arctic
• Positive phase: Lower pressure in the
Arctic
![Page 11: Winter 2016-17 SWOP Conference Call SWOP... · 2016-12-12 · Blue color in the Equatorial Pacific shows water temps 1-2 degrees Celsius below normal since mid-August . La Nina Winter](https://reader034.fdocuments.net/reader034/viewer/2022050103/5f4263866e8d8d0758738077/html5/thumbnails/11.jpg)
Arctic Oscillation (AO)
H
L
Negative phase: cold air comes southward
![Page 12: Winter 2016-17 SWOP Conference Call SWOP... · 2016-12-12 · Blue color in the Equatorial Pacific shows water temps 1-2 degrees Celsius below normal since mid-August . La Nina Winter](https://reader034.fdocuments.net/reader034/viewer/2022050103/5f4263866e8d8d0758738077/html5/thumbnails/12.jpg)
Arctic Oscillation (AO)
H
L
Positive phase: cold air suppressed northward
![Page 13: Winter 2016-17 SWOP Conference Call SWOP... · 2016-12-12 · Blue color in the Equatorial Pacific shows water temps 1-2 degrees Celsius below normal since mid-August . La Nina Winter](https://reader034.fdocuments.net/reader034/viewer/2022050103/5f4263866e8d8d0758738077/html5/thumbnails/13.jpg)
North Atlantic Oscillation
Mean pressure difference across the
North Atlantic Ocean between Iceland
and the Azores
• Negative phase: Weaker Icelandic
low and weaker Azores high
• Positive phase: Stronger Icelandic low
and stronger Azores high
![Page 14: Winter 2016-17 SWOP Conference Call SWOP... · 2016-12-12 · Blue color in the Equatorial Pacific shows water temps 1-2 degrees Celsius below normal since mid-August . La Nina Winter](https://reader034.fdocuments.net/reader034/viewer/2022050103/5f4263866e8d8d0758738077/html5/thumbnails/14.jpg)
North Atlantic Oscillation (NAO)
Negative phase: cold air drops due south into U.S.
Weaker Icelandic low…
more “amplified” pattern
Jet Stream
L
![Page 15: Winter 2016-17 SWOP Conference Call SWOP... · 2016-12-12 · Blue color in the Equatorial Pacific shows water temps 1-2 degrees Celsius below normal since mid-August . La Nina Winter](https://reader034.fdocuments.net/reader034/viewer/2022050103/5f4263866e8d8d0758738077/html5/thumbnails/15.jpg)
North Atlantic Oscillation (NAO)
Positive phase: cold air drops into SE Canada
Stronger Icelandic low…
less “amplified” pattern
Jet Stream
L
![Page 16: Winter 2016-17 SWOP Conference Call SWOP... · 2016-12-12 · Blue color in the Equatorial Pacific shows water temps 1-2 degrees Celsius below normal since mid-August . La Nina Winter](https://reader034.fdocuments.net/reader034/viewer/2022050103/5f4263866e8d8d0758738077/html5/thumbnails/16.jpg)
Negative AO and NAO can lead to cross-polar
flow from Siberia…Cold Outbreak for Illinois
![Page 17: Winter 2016-17 SWOP Conference Call SWOP... · 2016-12-12 · Blue color in the Equatorial Pacific shows water temps 1-2 degrees Celsius below normal since mid-August . La Nina Winter](https://reader034.fdocuments.net/reader034/viewer/2022050103/5f4263866e8d8d0758738077/html5/thumbnails/17.jpg)
What Phases are We In Now?
Arctic Oscillation (AO) is currently neutral
and is forecast to become positive
![Page 18: Winter 2016-17 SWOP Conference Call SWOP... · 2016-12-12 · Blue color in the Equatorial Pacific shows water temps 1-2 degrees Celsius below normal since mid-August . La Nina Winter](https://reader034.fdocuments.net/reader034/viewer/2022050103/5f4263866e8d8d0758738077/html5/thumbnails/18.jpg)
What Phases are We In Now?
North Atlantic Oscillation (NAO) is currently
negative and is forecast to remain negative
![Page 19: Winter 2016-17 SWOP Conference Call SWOP... · 2016-12-12 · Blue color in the Equatorial Pacific shows water temps 1-2 degrees Celsius below normal since mid-August . La Nina Winter](https://reader034.fdocuments.net/reader034/viewer/2022050103/5f4263866e8d8d0758738077/html5/thumbnails/19.jpg)
What Can We Expect?
• Below normal temperatures for the next
couple of weeks
• Bouts of cold/snow from early January
through February
• NOTE: La Nina pattern with negative AO
and NAO could lead to an Arctic outbreak
as far south as central Florida at some
point this winter
![Page 20: Winter 2016-17 SWOP Conference Call SWOP... · 2016-12-12 · Blue color in the Equatorial Pacific shows water temps 1-2 degrees Celsius below normal since mid-August . La Nina Winter](https://reader034.fdocuments.net/reader034/viewer/2022050103/5f4263866e8d8d0758738077/html5/thumbnails/20.jpg)
Average December-February Snowfall
Effingham: 13.0”
Springfield: 17.5”
Peoria: 20.2”
![Page 21: Winter 2016-17 SWOP Conference Call SWOP... · 2016-12-12 · Blue color in the Equatorial Pacific shows water temps 1-2 degrees Celsius below normal since mid-August . La Nina Winter](https://reader034.fdocuments.net/reader034/viewer/2022050103/5f4263866e8d8d0758738077/html5/thumbnails/21.jpg)
Chances of a White Christmas
26-40%
11-25%
![Page 22: Winter 2016-17 SWOP Conference Call SWOP... · 2016-12-12 · Blue color in the Equatorial Pacific shows water temps 1-2 degrees Celsius below normal since mid-August . La Nina Winter](https://reader034.fdocuments.net/reader034/viewer/2022050103/5f4263866e8d8d0758738077/html5/thumbnails/22.jpg)
Questions?