Penn State Weather Camps

Basic Weather Forecasting Guidelines

Know what to expect! = Climo.

And the Heavens cried …. rain!whilst the lightning bolts cameDeluge Part Dos (2014)!Deluge Part Uno (2013)!

WelcomeTo Penn State!

Basic Forecast GuidelinesWhat 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 GuidelinesWhat 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!

Basic Forecast GuidelinesClimatology Forecast = averages for today

Persistence Forecast = yesterday’s values

Extrapolation/trend Forecast = Look upstream to see what the wind’s bringing in !◦ Satellite IR - Satellite VIS - Radar - sfc. map 1 - sfc. map 2

Thunderstorms/Moist Convection◦Triggers ?◦Fuel

LI Cape

Basic Forecast GuidelinesThe “Models”

◦Simulate future state of atmosphere◦Higher resolution / lower resolution

The “Models” ◦Lower Res. (GFS)◦Higher Res. (NAM)◦Higher Res. (HRRR)

Your competition !!!

◦The National Weather Service

◦The Weather Channel

◦Accuweather

◦The guy or gal to your left and right