1. Weather Forecasting

2. How do you make sense of this???

3. Weather Patterns
AIR MASSES- huge body of air that has similar temperature, pressure, and humidity throughout
4 types
FRONT: The area where air masses meet and do not mix

4. FORE FRONT There are 4 types of air fronts: Warm Cold Stationary
Occluded

5. Warm Front Where WARM/ MOIST air replaces COLD/DRY air
Associated with good weather. If precipitation is present it will be ahead of the front

6. Warm Front Colder 45 Temperatures Warm Front 38 55 Warmer Temperatures62
Warm Front: A transition zone where warm, moist air replaces cold, dry air. Typically, warm fronts only travel at half the speed than that of cold fronts (because of the density principle). These fronts are depicted as the red line with semicircles pointing towards the direction of movement.

7. Warm Front (Vertical Profile)
air
Cold air
Since warm air is less dense than cold air, this air mass can be best referred to as a shallow wedge of air, which struggles to lift the heavier/denser cold air. A good analogy can be a weightlifter trying to push a large dump truck…this individual will have trouble pushing the vehicle. Warm fronts do not slope in the vertical as much as cold fronts do. The result will be the warm air gently overriding the cooler, less dense air, thus only light to moderate showers will form at best. The rain/snow will fall ahead of the warm front.
Light to moderate showers and a few thunderstorms will be possible on the north side of the warm front. This is due to the gentleness of the slope of this kind of air mass.

8. Cold Front
Where COLD/DRY and stable air replaces WARM/MOIST unstable air.
Associated with bad weather (thunderstorms, snow, etc.) due to the collision of two front systems (typically warm and cold)

9. Cold Front Colder 27 Temperatures 54 33 Warmer Temperatures 62
Typically, bad weather (thunderstorms) is associated with cold fronts. This threat peaks especially when cold fronts intersect warm fronts near low pressure systems. 62

10. Cold Front (Vertical Profile)
Advancing
Cold air
Rising Warm
air
Because cold air is denser than warm air, it can be best referred to as a deep dome of air, capable of easily lifting the warmer, less dense air, forming showers and thunderstorms through the collision and coalescence process.

11. Stationary Front
Boundary that has no movement but separates warm, moist air from cold, dry air.
Associated with good or bad weather. If bad weather, widespread showers or thunderstorms can happen on both sides.

12. Stationary Front Cold Air Warm Air
Stationary Front: A boundary that has essentially no movement, but separates warm, moist air from cold, dry air. It is depicted by an alternating red and blue line containing blue triangles and red semicircles. The triangles point towards the warmer air, while the semicircles point towards the cooler air.
Here, showers and thunderstorms can be more widespread/numerous on both sides of this front, as this precipitation continues to move parallel to this boundary over the same areas. This scenario can result in extensive flooding given the right conditions.
Warm
Air

13. Occluded Fronts Cold front overtakes a warm front
Usually associated with a storm dying down

15. How many fronts can you identify on this map?

16. Different Temperatures - Different Pressures
Less
Dense
Pressure
Cool
Air
Denser
More
Pressure
Warm
Air

17. Pressure Gradient
Pressure can be shown on a map as well to indicate weather.
Low pressure brings overcast/stormy weather. Wind flows in a COUNTER CLOCKWISE direction
High pressure brings clear/ sunny weather. Wind flows out and CLOCKWISE

18. Which state has high pressure?

19. How many “Lows” are on this map?

20. ISOBARS Isobars: lines that connect points of equal air pressure
Form enclosed circle to represent areas of high or low pressure.

21. Pressure Gradient
Difference in pressure over a given distance---between isobars
Close together = steep pressure gradient
STRONG winds
Far apart = gentle pressure gradient
Light winds
Just like contour lines

22. Pressure Gradient Force

24. Practicing Drawing & Recognizing Fronts