Weather Forecasting

How do you make sense of this???

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

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

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

Warm Front Colder 45 Temperatures Warm Front 38 55 Warmer Temperatures 62 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.

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.

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)

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

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.

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.

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

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

How many fronts can you identify on this map?

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

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

Which state has high pressure?

How many “Lows” are on this map?

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

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

Pressure Gradient Force

Practicing Drawing & Recognizing Fronts