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Be A Citizen Weather Reporter

Could you help save lives with your homemade weather instruments? 

Maybe so!

The National Weather Service Cooperative Observer Program is a network of 

more than 11,000 volunteers who report weather observations from farms, 

urban and suburban areas, National Parks, seashores, and mountaintops. Data 

from volunteer weather observers are used to defi ne the climate of the United 

States and to help measure long-term climate changes, as well as to provide 

real-time information to support forecasts, warnings, and other public service 

programs of the National Weather Service.

The Cooperative Observer Program was offi cially created in 1890, but the history 

of volunteer weather observers is even older. John Campanius Holm recorded the 

earliest known weather observations in the United States in 1644-45. George 

Washington, Thomas Jeff erson, and Benjamin Franklin were also serious weather 

observers. Thomas Jeff erson maintained an almost unbroken record of weather 

observations between 1776 and 1816, and George Washington took his last 

observation just a few days before he died.

An essential part of any weather observing station is a system for keeping accurate records of observations. Here’s how to set up a Weather Journal, and some 

tips for making weather forecasts from your observations!

A young volunteer in Granger, Utah (around 1930) operates a cooperative 

weather station where he observes temperature, precipitation, sky conditions, etc. Courtesy NWS.

What You Will Do

Set up a Weather Journal and record 

regular measurements from the 

instruments in your Weather Station

“The whole point is that person is helping out their neighbors 

by sharing that information”. 

Chad Gimmestad - NWS Senior Meteorologist

From minute 12:18 of episode 1 of 

The Crowd & The Cloud: http://crowdandcloud.org/watch-the-episodes/episode-one
National Oceanic and Atmospheric Administration (NOAA) 71

Science | SERVICE | Stewardship Understand the Eart

What You Will Need

Copies of “Weather Journal Data Form”

How to Do It

At least once each day, record the measurements 

from each of the instruments in your weather 

station. Notice that there are two columns for 

“Barometric Pressure” and “Humidity.” Record 

the readings from your instruments in the “Instrument” columns. The “NWS” column is where 

you can record measurements from your local 

weather office. Comparing the two columns gives 

you a way to convert your instruments readings 

to approximately the same scale used for official 

weather measurements. 

Over time, you should begin to see patterns in 

your data. When the weather changes (it gets 

windy, starts raining, etc.), check your records 

for a day or two before. Was there a change in 

temperature, humidity, or barometric pressure? 

Did the wind direction shift? These kinds of 

changes can give clues about what kind of weather is coming. See “Tips for Amateur Forecasters” 

for more information about these clues.

Tips for Amateur Forecasters

from the National Weather Service

Below is a general summary of wind and barometer indications in the United States. The amateur forecaster should 

modify the table as needed, based on his or her own observations. Barometric pressures in this table are in inches of 

mercury at sea level. If you use local weather reports to calibrate your instruments, you don’t have to worry about this 

because official measurements are converted to sea level before they are reported to the public. A general rule of thumb 

is that atmospheric pressure decreases by one inch of mercury for every 1,000 feet of elevation.

If the Wind is Blowing from and the Barometer is the Probable Weather is

Southwest to Northwest 30.10 to 30.20 and steady Fair with slight temperature change for one to two 

 days

Southwest to Northwest 30.10 to 30.20 and rising rapidly Fair, followed by rain within two days

Southwest to Northwest 30.20 and above and steady Continued fair, with little temperature change

Southwest to Northwest 30.20 and above and falling slowly Slowly rising temperature and fair for two days

South to Southeast 30.10 to 30.20 and falling slowly Rain within 24 hours

South to Southeast 30.10 to 30.20 and falling rapidly Wind increasing in force, rain within 12 to 24 hours

Southeast to Northeast 30.10 to 30.20 and falling slowly Rain in 12 to 18 hours

Southeast to Northeast 30.10 to 30.20 and falling rapidly Increasing wind, and rain within 12 hours

East to Northeast 30.10 and above and falling slowly In summer: rain may not fall for several days

In winter: rain within 24 hours

East to Northeast 30.10 and above and falling rapidly In summer: rain likely within 12 to 24 hours

In winter: rain or snow, with increasing winds

Southeast to Northeast 30.00 or below and falling slowly Rain will continue one to two days

Southeast to Northeast 30.00 or below and falling rapidly Rain, with high wind, followed by clearing within 36 

hours, and by colder temperatures in winter 

South to Southwest 30.00 or below and rising slowly Clearing within a few hours, and fair for several 

 days

South to East 29.80 or below and falling rapidly Severe storm soon, followed by clearing within 24 

hours, and by colder temperatures in winter 

East to North 29.80 or below and falling rapidly Severe northeast gale and heavy precipitation

In winter: heavy snow, followed by a cold wave

Changing to West 29.80 or below and rising rapidly Clearing and colder
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Want to Do More?

Are you interested in becoming a volunteer 

weather observer? SKYWARN is a volunteer 

program established by NOAA’s National Weather Service and partner groups to identify and 

describe severe local storms. Since the program 

started in the 1970s, information provided 

Weather Journal Data Form

Date Time Temperature Barometric Pressure Humidity Precipitation Wind

 Instrument NWS Instrument NWS Type Amount Speed Direction

by SKYWARN Spotters has helped the National Weather Service to issue more timely and 

accurate warnings for tornadoes, severe thunderstorms, and flash floods. In some areas, 

Spotters also are trained on warning signs for 

earthquakes, landslides, avalanches, volcanic 

ashfall, and coastal hazards such as tsunamis, 

water spouts, and rip currents. See https://www.

weather.gov/skywarn/ for more information.