Basic Forecast Guidelines

Penn State Weather Camps Sat I Sat I - Sat II - NWS - Radar - RadarSat II NWSRadar sfc. map 1 sfc. map 1 - sfc. map 2 – sfc map 3sfc. map 2sfc map 3 -> IR emission PROP to ? -> Temp and Height ?

Know what to expect! = Climo. JUNE 22

Basic Forecast Guidelines Climatology Forecast = averages for today Persistence Forecast = yesterday’s valuesyesterday’s values Modified Persistence -> Yesterday = First Guess -> Modify based on changes Conceptual Models

Basic Forecast Guidelines Modifying Persistence ◦What causes temperature to change?  Cloud cover: ◦ Day Vs. Night  Precipitation: ◦ When it rains T’s tend to be higher/lower? Why?  Wind and Fronts: ◦ Direction  N vs. S ◦ Speed  Day Vs. Night

Basic Forecast Guidelines L L

11z TUES -> 70,65,60 Isodrosotherms -> Low, Cold & Warm Fronts L

Basic Forecast Guidelines

What causes rain? ◦Need clouds!  Will any ole cloud do? ◦Moisture supply  Bodies of water – Moisture content of air ◦Upward motion:  How does this affect clouds/precip.?  Mechanisms for “lift” ◦ Fronts – Topography – Low Pressure – Jet stream dist. ◦(In) stability:  Warm down low … cold up high!