Synoptic Weather: Precipitation, Air Masses & Fronts

1. Synoptic weather Precipitation & Air Masses & Fronts

2. High Pressure Pressures of 1000 mb and above. Symbolized with an H Clock-wise winds and outwards Winds sink at the center. Nice weather – clear. Low Pressure Pressures of 900-1000 mb Symbolized with an L Counter-clockwise winds and inwards Winds rise at the center. Hurricane LOUSY weather Air pressure

3. How did this happen? • Workers clean these with steam and didn’t open anyvalves to release pressure…OUTCOME:no job!

4. What is precipitation? • Water that falls from the atmosphere. • Can be in any phase of water based on the air temperature. • Above 32oF (0oC) = Rain • Below 32oF (0oC) = Snow

5. Types of Precipitation • Rain • Liquid precipitation • Snow • Frozen precipitation • Hail • Snow that melted then refroze • Sleet/Freezing Rain • Rain that either freezes on the surface or just before.

6. Air Masses • What is an air mass? • Air that has formed into large bodies of uniform temperature and moisture. • Named for where it comes from. • MUST have both moisture and temperature in its name… • m = Maritime (wet) • c = continental (dry) • T = tropical (hot), A = Artic (very cold) P = Polar (cold)

7. c = Continental (dry) P = Polar (cold) cP cT cA m= Maritime (wet) T = Tropical (warm) mP mT Air Masses

8. MAP

9. Weather Fronts • These are boundaries between air masses and pressures, where most weather events occur. • Three types: • Warm Front • Cold Front • Occluded • Hmmm what kind of air is coming with a cold front?

10. Cold Front (DRAW) • Notice how sharply the air rises? • Where do the clouds form? • Cloud Type?

11. Warm front (DRAW) • Notice warm air rising, slowly… • Where do clouds form? • Cloud Type?

12. Occluded (not moving) • Notice how the air rises? • Where are the clouds? • Type of clouds?