1. John Lewis, Senior Forecaster National Weather Service
2016 So Far/
A Look Ahead
John Lewis, Senior Forecaster
National Weather Service
Little Rock, Arkansas

2. In this Saga…
Across the United States, 2016 has been the year of the flood and also the year of the drought.
Ditto for Arkansas, with flooding in March and August followed by a developing drought in the fall. It has been warm as well.
The official forecast calls for dry/mild conditions to continue this winter based on a weak La Niña, but local climate suggests otherwise.

3. Precipitation in 2016
Through November

4. Precipitation in 2016 Through November Departure from average, with
plus values in the southeast
and minus values in the northwest.

5. Precipitation in 2016 Through November Month Amount Departure Rank Jan
2.07
-1.97
24th Dry
Feb
2.49
-1.23
31st Dry
Mar
9.86
+5.09
3rd Wet
Apr
5.99
+0.95
31st Wet
May
4.64
-0.51
55th Dry
Jun
3.14
-0.94
39th Dry
Jul
4.89
+1.18
28th Wet
Aug
7.59
+4.21
Sep
1.80
-1.79
20th Dry
Oct
1.65
-1.81
Nov
3.25
-1.04
46th Dry
Total
47.37
+2.13
41st Wet

6. Temperatures in 2016
Through November

7. Temperatures in 2016 Through November Month Amount Departure Rank Jan
39.5
+0.2
59th Cool
Feb
46.9
+3.8
24th Warm
Mar
55.5
+4.2
18th Warm
Apr
62.6
+2.1
32nd Warm
May
67.1
-1.6
30th Cool
Jun
79.0
+2.5
15th Warm
Jul
82.0
+1.7
20th Warm
Aug
80.0
+0.6
49th Cool
Sep
75.8
+2.9
16th Warm
Oct
67.0
+5.2
4th Warm
Nov
55.6
+5.7
5th Warm
Total
64.6

8. Thought For the Day
“There are three kinds of people…those who can count and those who can’t.”

9. Drought Monitor
December 6, 2016

10. Wet Pattern
March, 2016

11. Wet Pattern
March, 2016

12. Hot Summer

13. Hot Pattern
July 21, 2016

14. Heat Index Forecast
July 21, 2016

15. Actual Heat Index
July 22, 2016

16. Big Time Rain
June 22-28, 2016

17. Wet Pattern
August, 2016

18. Wet Pattern
August, 2016

19. Wet Pattern
August, 2016

20. The Tropics
Tropical systems struggle to form over the Atlantic basin given El Niño. The opposite is true with La Niña.

21. The Tropics
There were only four named storms (one hurricane) through July. There were eleven named storms thereafter.

22. The Tropics
Normal: 11
Matthew, Oct. 6
Normal: 6
Normal: 3

23. The Tropics

24. Dry Pattern
October, 2016

25. Relief Coming
November, 2016

26. Relief Coming
November, 2016

27. Relief Coming
November, 2016

28. Relief Coming
November, 2016

29. Relief Coming
November, 2016

30. A Dwindling El Niño
February 10, 2016

31. A Dwindling El Niño
April 27, 2016

32. Drought in South America
Because of El Niño
Drought in South America
From Reuters…
Problem: “Home to the world's largest fresh water supply, Brazil has not previously had much reason for conservation.”

33. Drought in South America
Because of El Niño
Drought in South America
From isciences…

34. ENSO
2016/Early 2017
El Niño
La Niña

35. Winter Temperature
Dec, 2016 – Feb, 2017

36. Winter Precipitation
Dec, 2016 – Feb, 2017

37. Dec/Jan/Feb Temperature
Transition Winter
Dec/Jan/Feb Temperature
Year
Average Temp
Departure
1959/1960
40.7°
-0.6°
1966/1967
40.9°
-0.4°
1983/1984
36.5°
-4.8°
1992/1993
2005/2006
42.8°
+1.5°
Total
40.4°
-0.9°

38. Dec/Jan/Feb Precipitation
Transition Winter
Dec/Jan/Feb Precipitation
Year
Amount
Departure
1959/1960
12.73
+0.61
1966/1967
7.83
-4.29
1983/1984
12.66
+0.54
1992/1993
12.57
+0.45
2005/2006
7.86
-4.26
Total
10.73
-1.39

39. Arctic Oscillation (AO)
Negative Phase

40. Arctic Oscillation (AO)
Negative Phase

41. Arctic Oscillation (AO)
Negative Phase

42. The Upcoming Winter? A Look Back to February 9, 2011
Big snow and ice storms have hit in La Niña years.

43. The Upcoming Winter?
In addition to snow/ice, the focus usually turns to severe weather. Severe storms are most active when La Niña is present (such as 1999, 2008, and 2011).

44. The Upcoming Winter?
Not only is there more severe weather, it starts early (January or February). One of the most violent tornadoes in recent memory was spawned on Super Tuesday (February 5th) in 2008.

45. The Bottom Line
While climate records indicate a chance of below average temperatures this winter, most guidance suggests a mild period.
There is some hope for appreciable precipitation this winter, not dry throughout.
If the AO goes negative, or we actually have a La Niña, that could mean more cold than expected or more severe weather than expected.

46. On the Web

47. The End
Thanks for coming!