1. MADISON’S CURRENT WEATHER
Madison Weather at 1000 AM CDT
TUE AUG Updated twice an hour at :05 and :25
Sky/Weather: SUNNY Temperature: 85 F (29 C) Dew Point: 76 F (24 C) Relative Humidity: 74% Wind: VRB7 MPH Barometer: 30.13F

2. Surface Weather Map from Today with Isobars & Fronts

3. Current Temperatures (oF) & Isotherms

4. Current Dewpoints (oF)

5. Current Winds Aloft at 34,000 Ft.

6. Tomorrow’s 7AM Forecast

7. ATM OCN 100 - Spring 2002 LECTURE 25 (con’t.)
MID-LATITUDE WEATHER SYSTEMS: PART II: THE EXTRATROPICAL CYCLONE
Introduction
The Norwegian Model of Extratropical Cyclones
Observed Weather Features surrounding Extratropical Cyclones
Life Cycle of an Extratropical Cyclone

8. Life Cycle of an Extratropical Cyclone See Fig. 11
Life Cycle of an Extratropical Cyclone See Fig Moran & Morgan (1997)

9. Incipient Cyclone Stage in the Life Cycle of an Extratropical Cyclone See Fig. 11.9A Moran & Morgan (1997)

10. The Surface Low & the Jet

11. Linkage between surface weather systems & winds aloft See Fig. 10
Linkage between surface weather systems & winds aloft See Fig Moran & Morgan (1997)

12. Wave Cyclone Stage in the Life Cycle of an Extratropical Cyclone See Fig. 11.9B Moran & Morgan (1997)

13. Occluding Stage in the Life Cycle of an Extratropical Cyclone See Fig
Occluding Stage in the Life Cycle of an Extratropical Cyclone See Fig. 11.9C Moran & Morgan (1997)

14. Bent-Back Occlusion Stage in the Life Cycle of an Extratropical Cyclone See Fig. 11.9D Moran & Morgan (1997)

15. Cyclone Families from TIROS

16. Occluded Cyclone over British Isles

17. E. MOVEMENTS OF EXTRATROPICAL WAVE CYCLONES
General Movements
Steering winds aloft

18. Zonal Circulation Regime Figure 10.10 Moran & Morgan (1997)

19. Meridional Circulation Regime Figure 10.10 Moran & Morgan (1997)

20. Stagnant Circulation Regime with Cut-off Lows & Blocking Highs Figure 10.13 Moran & Morgan (1997)

21. E. MOVEMENTS OF EXTRATROPICAL WAVE CYCLONES (con’t.)
General Movements
Regions of Cyclogenesis
Lee-side of mountains
Along east coasts of continents

22. Lee-slope Cyclogenesis See Fig.1 pg. 275, Moran & Morgan (1997)

23. E. MOVEMENTS OF EXTRATROPICAL WAVE CYCLONES (con’t.)
General Movements
Regions of Cyclogenesis
Lee-side of mountains
Along east coasts of continents
Principal Cyclone Tracks over North America

24. Storm Tracks see Fig. 11.16 of Moran & Morgan (1997)

25. E. MOVEMENTS OF EXTRATROPICAL WAVE CYCLONES (con’t.)
General Movements
Regions of Cyclogenesis
Principal Cyclone Tracks over North America
Time Sequences of Weather Events Single Point Forecasting

26. Weather along Storm Tracks (A) Warm Side vs. (B) Cold side see Fig. 11
Weather along Storm Tracks (A) Warm Side vs. (B) Cold side see Fig of Moran & Morgan (1997)

27. Windy, warm & rainy in Madison
Weather on Warm Side
Windy, warm & rainy in Madison

33. Weather on Cold Side
Development of a 5 inch snow storm in Madison (with temperatures in the teens)

37. Incipient Cyclone Stage in the Life Cycle of an Extratropical Cyclone See Fig. 11.9A Moran & Morgan (1997)

38. Wave Cyclone Stage in the Life Cycle of an Extratropical Cyclone See Fig. 11.9B Moran & Morgan (1997)

39. Occluding Stage in the Life Cycle of an Extratropical Cyclone See Fig
Occluding Stage in the Life Cycle of an Extratropical Cyclone See Fig. 11.9C Moran & Morgan (1997)

40. Bent-Back Occlusion Stage in the Life Cycle of an Extratropical Cyclone See Fig. 11.9D Moran & Morgan (1997)

41. Winter Weather Conditions
G. WINTER STORMS
Definitions
Winter Weather Conditions
Hazards of Winter Storms
HEAVY SNOW
ICE STORMS
STRONG WINDS
Ingredients of a Winter Storm
COLD AIR
MOISTURE
LIFT

42. See Figure 11.14 Moran & Morgan (1997)

43. Winter weather condition lasting 3 hours or more with:
WINTER STORMS (con’t.)
Blizzards
Winter weather condition lasting 3 hours or more with:
Strong winds (35 mph or more);
Snow & blowing snow with visibility less than 1/4 mile.

44. WINTER STORMS (con’t.)
Public Information Dissemination & Public Safety Precautions
Blizzard warnings;
Winter storm watches & warnings;
Ice storm warnings;
High wind warnings;
Wind chill warnings.

45. Cyclones along the Polar Front

46. Cross Section thru a cyclone

47. An extratropical cyclone

48. Typical cyclone tracks