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Weather Lab 6-8 / Week 12 / Wednesday
3/6
Week 12 · Forecast and Design

Wednesday

Station Lab: Forecast Day
// Your own forecast, and a weather-ready plan for home
⏱ about 20 min

Wednesday: Station Lab: Forecast Day

Raven pins two blank forecast cards to the Station Rooftop board. One says CREW. One says OFFICIAL.

"We fill ours first," she says. "No peeking at the official one until ours is done."

Rocket reads the log aloud: pressure steady, wind from the west, clouds scattered and puffy.

"Upper 60s," he decides. "Partly cloudy. Breezy from the west. Twenty percent chance of rain."

"What do you notice that makes you say twenty and not fifty?" Raven asks.

"Steady pressure," Rocket says. "And no thickening clouds."

Nova lights the OFFICIAL card. "Now compare," she says. "Then wait a day. The sky gets the final vote."

Rocket grins. "I like this kind of test."

Your mission

You will write a one-day forecast from your station log. Then you compare it with the official National Weather Service forecast and check both tomorrow.

A forecast is only as good as its check. Tomorrow you record what really happened.

  • Your station log with the last three days of readings
  • Two index cards or two boxes drawn on paper, labelled CREW and OFFICIAL
  • A pencil
  • A grown-up who can read the official forecast for your area aloud from weather.gov
  • Your rain gauge, wind flag and cloud log for tomorrow's check
Safety first
Take readings only in calm weather. Never go outside during a thunderstorm, flood or high wind to check a forecast.
Your station stays on the ground, a railing or a windowsill. A grown-up handles anything on a roof or ladder.
Never look at the Sun while checking the sky.
  1. Read the last three days in your log. Write down the pressure trend, wind direction, cloud type and any rain.
  2. Decide tomorrow's high as a range word, such as mid 60s. Write it on the CREW card.
  3. Decide the sky word from the eighths table. Write it on the CREW card.
  4. Decide the wind direction and speed word. Write them on the CREW card.
  5. Choose a chance of rain as a percent and its matching word. Write them on the CREW card.
  6. Now ask your grown-up to read the official forecast for tomorrow for your area. Copy the same four items onto the OFFICIAL card.
  7. Circle every item where the two cards agree. Note each disagreement in the table.
  8. Tomorrow, record what actually happened in the last row: high temperature, sky, wind and whether the gauge caught at least 0.01 inch.
ItemCREW forecastOFFICIAL forecastWhat actually happened
High temperature
Sky
Wind
Chance of rain
PREDICT BEFORE YOU COMPARE
  • Read the question.
  • Tap your answer.
Your log shows steady pressure and scattered puffy clouds. Which chance of rain fits best?
Tomorrow your gauge shows 0.02 inch. Did measurable rain happen?

Checking a forecast

A forecast is not finished until you check it against what happened. The crew calls this the sky's final vote.

A 20 percent chance of rain that ends in rain is not wrong. Twenty percent means rain happens one time in five.

What matters is the pattern over many forecasts. Keep forecasting for a week and see how your percents hold up.

Notice where the official forecast and yours differed. Which one did the sky agree with?

What the lab showsTrue or false?
You should write your own forecast before reading the official one.?
A 20 percent chance of rain means rain is impossible.?
A forecast should be checked against what actually happened.?
A gauge reading of 0.01 inch counts as measurable rain.?
WHY THIS EXERCISEChecking forecasts against the real sky is how forecasters, and you, get better.
The two cards in this lab are labelled CREW and ____.
A 20 percent chance of rain means rain about one time in ____. Type a number.
FORECAST DAY, IN ORDER
  • Tap a card.
  • Then tap its spot.
1First
2Second
3Third
4Last
Try it
Keep forecasting every evening this week. Add a new pair of cards each day and keep score of which card the sky agreed with.
On paper, draw tomorrow's sky as you forecast it. Show the eighths of cloud, a wind arrow and a label for the high temperature.

A real forecast, made and checked. Tomorrow you read data on heat, shade and buildings.

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