California Weather

Climate vs. Weather

Climate:

Long term average conditions

Weather:

The conditions day to day

Climate vs. Weather

Climate:

Weather:

Water Year

Water Year

Hydrologic Water YearCalifornia:

October 1 – September 30

Precipitation

•Northern Sierra 8 Station Index Mt. Shasta City

Shasta Dam

Mineral

Brush Creek

Quincy

Sierraville

Pacific House

Blue Canyon

•San Joaquin 5-Station Index

Calaveras Big Trees

Hetch Hetchy

Yosemite Headquarters

North Fork

Huntington

Precipitation

PRISM (Parameter-elevation Regressions on Independent Slopes Model)

Winter Summer

SUN

More Heating Less Heating

SameSolar

Energy

200 MB

500 MB

700 MB

850 MB

1013 MB

0 +10 +20-10-20-30-40-50-60Degrees Centigrade

5,000 Feet

Sea Level

10,000 Feet

18,000 Feet

39,000 Feet

0 +10 +20-10-20-30-40-50-60

Troposphere; lowest layer

Temperature:Pressure:

Jet Stream

Jet Stream

Winter vs. Summer in California

Winter: Jet points toward CA

COLD From NW, Alaska

Winter Jet toward CA

Winter: Jet points toward CA

COLD From NW, Alaska

Winter Jet toward CA

Winter: Jet points toward CA

COLD From NW, Alaska

Winter Jet toward CA

Winter Jet toward CA

WARM: From West or SW “Pineapple Express” (Atmospheric Rivers)

Winter Jet toward CA

WARM: From West or SW “Pineapple Express” (Atmospheric Rivers)

DRY Summers: Jet points toward Washington, Canada

Summer Jet Stream

DRY Summers: Jet points toward Washington, Canada

Summer Jet Stream

DRY Summers: Jet points toward Washington, Canada

Summer Jet Stream

LWARM

COLD

Boundary between 2 air masses

Front

LWARM

COLD

Boundary between 2 air masses

Front

Air in motion caused High a Low Pressure

Wind

Air in motion caused High a Low Pressure

Speed measured with an anemometer

Wind

Air in motion caused High a Low Pressure

Speed measured with an anemometer

Direction described from which it is blowing

Wind

TemperatureHumidityPressureWind SpeedWind Direction

Radiosonde ; Weather Balloon

National Weather Service Launches twice daily 12 UTC (4 AM PST) and 00 UTC (4 PM PST)

H HLL

Weather Map

Demonstration-

Explaining

AIR PRESSURE!

CloudyRainy orWorsening

Surface Low Pressure

L cyclonic (counter- clockwise) convergence

H

anticyclonic (clockwise) divergence

Improving or clearing skies

Surface High Pressure

Moisture + Lift = Precipitation

Orographic Precipitation

Orographic Precipitation

Numerical Weather Prediction

Summary

Varying amounts of Sunlight create the jet stream and weather

A few storms per year determine most of State’s water supply