The verb “forecast” is widely used in English, especially when talking about weather, finance, and predictions. However, its past tense forms can be confusing, even for native speakers. Is it forecast or forecasted? Both appear in writing, but which one is correct, and when should each be used?
Understanding the correct past tense of “forecast” is essential for clear and accurate communication in academic essays, business reports, journalism, and everyday conversations. Since irregular verbs like “forecast” sometimes have multiple acceptable past forms, learners often feel uncertain about which form sounds natural and correct.
Mastering this topic will boost your grammatical accuracy and confidence, helping you sound more professional and fluent. This comprehensive guide is designed for English learners, teachers, editors, writers, and exam candidates who want a thorough understanding of the past tense of “forecast.”
In this article, you will find detailed explanations, grammar tables, abundant examples, rules, common mistakes, practice exercises with answers, and advanced insights. Let’s dive deep and clarify everything about using “forecast” in the past tense.
Table of Contents
- 3. Definition Section
- 4. Structural Breakdown
- 5. Types or Categories
- 6. Examples Section
- 7. Usage Rules
- 8. Common Mistakes
- 9. Practice Exercises
- 10. Advanced Topics
- 11. FAQ Section
- 12. Conclusion
3. Definition Section
3.1 What Does “Forecast” Mean?
The word forecast functions both as a verb and a noun.
- As a verb, it means to predict or estimate a future event or condition.
- As a noun, it refers to the actual prediction or report.
Examples:
- Verb: The meteorologists forecast heavy rain for tomorrow.
- Noun: The weather forecast predicts sunshine next week.
- Noun: The economic forecast suggests growth will slow down.
3.2 Grammatical Classification
Forecast is classified as an irregular verb. Unlike regular verbs, which form the past tense by simply adding -ed (e.g., work → worked), irregular verbs can have unpredictable forms.
Some irregular verbs, like cut, put, broadcast, have identical base, past, and past participle forms. “Forecast” typically follows this pattern, but it also allows a regularized form: forecasted.
3.3 The Concept of Past Tense in English
English expresses the past using four main tenses:
- Simple Past: Completed actions in the past. (e.g., She forecast rain.)
- Past Continuous: Ongoing past actions. (e.g., They were forecasting storms.)
- Past Perfect: Actions completed before another past action. (e.g., They had forecast snow before it fell.)
- Past Perfect Continuous: Actions ongoing before another past event. (e.g., They had been forecasting rain all week.)
This article focuses mainly on the simple past tense form of “forecast.”
3.4 Past Tense of “Forecast”: Overview
Unlike many verbs, “forecast” has two acceptable past tense forms:
- forecast (unchanged from base form)
- forecasted (regular -ed ending)
Both are widely recognized, but there are stylistic, regional, and contextual preferences, which we will explore in detail.
4. Structural Breakdown
4.1 The Base Form: forecast
The base form is used for the infinitive, present simple (except third person singular), and imperative.
Examples:
- They forecast rain for tomorrow.
- Analysts forecast growth next year.
- Please forecast the expected demand.
4.2 Past Tense Forms
| Tense/Aspect | Base Form | Past Simple | Past Participle | Present Participle | 3rd Person Singular |
|---|---|---|---|---|---|
| Example | forecast | forecast / forecasted | forecast / forecasted | forecasting | forecasts |
Note: Both forecast and forecasted can serve as past simple and past participle forms.
Corpus evidence (such as COCA and BNC) indicates that forecast is significantly more common as the past form, especially in professional and academic writing.
4.3 How to Form the Simple Past of “Forecast”
- Using “forecast” (unchanged form):
- This follows the “zero change” irregular pattern like put, cut, broadcast.
- Preferred in formal, traditional styles.
- Using “forecasted” (-ed form):
- Formed by adding the regular past tense suffix -ed.
- Sometimes preferred in American English or technical contexts.
- Considered acceptable but more informal or modern.
4.4 Pronunciation Notes
- “Forecast” (base and past): /ˈfɔːrkæst/ (US) or /ˈfɔːkɑːst/ (UK)
- “Forecasted”: /ˈfɔːrkæstɪd/ (US) or /ˈfɔːkɑːstɪd/ (UK)
The pronunciation of forecast remains the same whether present or past. For forecasted, pronounce the -ed as a separate syllable: -id.
5. Types or Categories
5.1 Using “forecast” as an Irregular Verb
When using forecast unchanged for the past tense, it follows the pattern of other “zero change” irregular verbs.
Examples:
- The meteorologist forecast a storm last night.
- They forecast high inflation in 2020.
- The report forecast a sharp decline in profits.
This form is traditionally preferred, especially in formal writing.
5.2 Using “forecasted” as a Regular Verb
Adding -ed to form forecasted follows regular conjugation rules. It is accepted, mainly in American English and some technical fields.
Examples:
- They forecasted a drop in demand.
- Scientists forecasted warmer winters.
- The team forecasted growth by 5%.
5.3 Regional and Stylistic Variations
Preferences vary:
- British English: Strongly prefers forecast.
- American English: Accepts both, with forecasted more common than in the UK.
- Formal contexts: Favor forecast.
- Technical writing (e.g., meteorology, finance): Sometimes uses forecasted.
5.4 Past Participle in Perfect Tenses
Both forms can serve as the past participle in perfect tenses:
- They have forecast rain.
- They have forecasted rain.
- Scientists had forecast an earthquake.
- Scientists had forecasted an earthquake.
6. Examples Section
6.1 Basic Past Simple Examples
- The meteorologist forecast a hurricane last week.
- They forecasted a drop in sales last quarter.
- Experts forecast warmer temperatures yesterday.
- The company forecasted strong earnings last year.
- The agency forecast snow for Saturday.
- Economists forecasted a slowdown in growth.
- The report forecast increased unemployment.
- Investors forecasted market volatility.
6.2 Examples in Past Perfect and Present Perfect
- By morning, the scientists had forecast an earthquake.
- Economists have forecasted a recession this year.
- The meteorologists had forecast rain before it started.
- Financial experts have forecasted inflation.
- They had forecast problems before launch.
- Analysts have forecasted a recovery.
6.3 Examples with Both Forms Side-by-Side
- Economists forecast / forecasted slower growth in 2020.
- The company forecast / forecasted record sales last quarter.
- The team has forecast / forecasted increased demand.
- They had forecast / forecasted the downturn months ago.
6.4 Formal vs. Informal Context Examples
- Formal: The panel forecast a decline in GDP.
- Informal: They forecasted rain, but it was sunny.
- Formal: The committee forecast a budget deficit.
- Informal: The weather app forecasted thunderstorms.
6.5 Industry-Specific Examples
- Weather: The agency forecasted snow overnight.
- Finance: Analysts forecast profits to rise.
- Technology: Experts forecasted increased AI adoption.
- Energy: The department forecast higher demand for electricity.
6.6 Passive Voice Examples
- A storm was forecast for the weekend.
- A storm was forecasted for the weekend.
- Heavy rain was forecast by meteorologists.
- Economic growth was forecasted by the IMF.
6.7 Tables of Examples
| Table 2: Examples with “forecast” (unchanged past) |
|---|
| The experts forecast a mild winter. |
| They forecast a budget surplus. |
| The report forecast higher taxes. |
| The agency forecast snow tomorrow. |
| Economists forecast a slow recovery. |
| Table 3: Examples with “forecasted” |
|---|
| They forecasted a sharp decline in sales. |
| The company forecasted supply shortages. |
| Experts forecasted traffic congestion. |
| The scientists forecasted an earthquake. |
| Analysts forecasted a market crash. |
| Table 4: Simple Past vs. Perfect Tense |
|---|
| She forecast rain yesterday. (Simple Past) |
| She has forecast rain all week. (Present Perfect) |
| They forecasted a shortage last year. (Simple Past) |
| They had forecasted a shortage before it happened. (Past Perfect) |
| Table 5: Regional Preferences |
|---|
| UK: The BBC forecast heavy snow. |
| US: The weather service forecasted thunderstorms. |
| UK: Economists forecast growth to slow. |
| US: Analysts forecasted market volatility. |
7. Usage Rules
7.1 Acceptability of Both Forms
Both “forecast” and “forecasted” are grammatically correct past tense and past participle forms.
However, “forecast” is generally more widely accepted and traditional, especially in formal and British English.
7.2 Formality and Registers
- Formal and academic writing: prefer forecast.
- Conversational, American English, technical fields: may accept or prefer forecasted.
7.3 Consistency in Usage
Within a document or conversation, choose one form and stick to it to avoid inconsistency and confusion.
Example:
- Consistent: They forecast rain and then snow.
- Inconsistent: They forecasted rain and then they forecast sunshine. (Avoid)
7.4 Use in Perfect and Passive Constructions
Both forms can be used as past participles in perfect and passive structures.
- They have forecast / forecasted a recession.
- A storm was forecast / forecasted by meteorologists.
7.5 Common Exceptions or Less Preferred Forms
- Some style guides discourage forecasted as less traditional.
- Historically, forecasted is a later development, regularizing the verb to fit standard -ed patterns.
7.6 Special Cases: Forecast as a Noun
Remember, noun forms don’t have tense.
Examples:
- Correct: Yesterday’s forecast was inaccurate.
- Incorrect: The forecasted was wrong.
8. Common Mistakes
8.1 Using Only “forecasted” When “forecast” Is Preferred
Incorrect: In very formal writing: They forecasted rain.
Correct: They forecast rain.
8.2 Inconsistent Tense Forms
Incorrect: They forecasted rain and then they forecast sunshine.
Correct: They forecasted rain and then sunshine. OR They forecast rain and then sunshine.
8.3 Mispronunciation
- “Forecasted” should be pronounced forecast-id, not fore-cas-tid.
- “Forecast” pronunciation remains the same in all tenses.
8.4 Confusing noun and verb forms
Incorrect: The forecasted was wrong.
Correct: The forecast was wrong.
8.5 Overregularization of the Past Tense
Assuming all verbs take -ed, some overuse forecasted.
Correction: Learn which verbs are irregular and their accepted forms.
8.6 Examples Table
| Incorrect | Correct | Explanation |
|---|---|---|
| They forecasted rain last night. (formal) | They forecast rain last night. | Prefer “forecast” in formal writing. |
| He forecasted and then forecast snow. | He forecasted rain and then snow. | Maintain tense consistency. |
| The forecasted was wrong. | The forecast was wrong. | “Forecast” is a noun here; no -ed. |
| They has forecasted snow. | They have forecasted snow. | Correct auxiliary verb. |
| It was forecasteded to rain. | It was forecasted to rain. | Remove extra suffix. |
9. Practice Exercises
9.1 Fill-in-the-Blank
| Question |
|---|
| 1. The company ______ (forecast) record profits last year. |
| 2. The weather agency ______ (forecast) a storm for the weekend. |
| 3. Analysts have ______ (forecast) a slowdown in growth. |
| 4. They ______ (forecast) rain yesterday. |
| 5. Economists had ______ (forecast) a recession before it started. |
| 6. The experts ______ (forecast) severe flooding. |
| 7. The scientists ______ (forecast) warmer winters decades ago. |
| 8. Investors ______ (forecast) market volatility last month. |
| 9. They have ______ (forecast) higher taxes. |
| 10. The meteorologists ______ (forecast) snow by Monday. |
9.2 Identify the Correct Form
| Question |
|---|
| 1. Scientists ___________ a heatwave last week. a) forecast b) forecasted c) forecasts |
| 2. The news agency ___________ rain tomorrow. a) forecasted b) forecast c) forecasting |
| 3. They have ___________ a decline in profits. a) forecast b) forecasted c) forecasts |
| 4. The team ___________ growth last quarter. a) forecast b) forecasted c) forecasts |
| 5. Economists ___________ inflation this year. a) forecast b) forecasted c) forecasting |
9.3 Error Correction
- They has forecasted snow.
- The forecasted was inaccurate.
- Scientists forecasted and then forecast rain.
- They forecasted rain yesterday in the report formal.
- Investors has forecast growth.
9.4 Sentence Construction
- Write a formal sentence in the past tense using forecast.
- Write an informal sentence in the past tense using forecasted.
- Create a sentence using have forecast.
- Create a passive voice sentence with was forecast.
- Construct a sentence with had forecasted.
9.5 Mixed Tense Application
- By the time the event started, experts ___________ (already, forecast) rain.
- They ___________ (forecast) a recession last year.
- Analysts ___________ (have, forecast) an increase in demand.
- A storm ___________ (be, forecast) for Saturday.
- They ___________ (forecast) snow for last weekend.
9.6 Answer Key
9.1 Fill-in-the-Blank Answers
- forecast / forecasted
- forecast / forecasted
- forecast / forecasted
- forecast / forecasted
- forecast / forecasted
- forecast / forecasted
- forecast / forecasted
- forecast / forecasted
- forecast / forecasted
- forecast / forecasted
9.2 Identify the Correct Form
- a) forecast or b) forecasted
- a) forecasted or b) forecast
- a) forecast or b) forecasted
- a) forecast or b) forecasted
- a) forecast or b) forecasted
9.3 Error Correction
- They have forecasted snow.
- The forecast was inaccurate.
- Scientists forecasted rain and then sunshine. (Consistency)
- They forecast rain yesterday in the formal report.
- Investors have forecast growth.
9.4 Sentence Construction (sample answers)
- The committee forecast a decline in revenue.
- They forecasted rain, but it never came.
- Experts have forecast a rapid recovery.
- Heavy snow was forecast by the agency.
- They had forecasted strong winds before the storm hit.
9.5 Mixed Tense Application
- had already forecast / forecasted
- forecast / forecasted
- have forecast / forecasted
- was forecast / forecasted
- forecast / forecasted
10. Advanced Topics
10.1 Corpus Data and Frequency Analysis
Corpus studies show that forecast (unchanged) is much more common than forecasted.
| Corpus | forecast (past) | forecasted |
|---|---|---|
| COCA (American English) | approx. 85% | approx. 15% |
| BNC (British English) | approx. 95% | approx. 5% |
This pattern indicates forecast is preferred overall, but forecasted appears more often in US English.
10.2 Historical Development of “Forecasted”
“Forecast” originated as a compound of “fore-” (before) and “cast” (throw, project). Historically, it was zero-change in past tense like “broadcast.”
“Forecasted” arose later as a back-formation from the regular tense pattern, becoming increasingly accepted, especially in North America.
10.3 Register, Style, and Genre Considerations
- Journalism and academic writing: Prefer forecast.
- Scientific and technical writing: May use either, sometimes leaning toward forecasted.
- Business reports: Usually prefer forecast.
- Casual speech: Both are common; forecasted may sound more natural to some speakers.
10.4 Comparison with Similar Irregular Verbs
| Verb | Base | Past Simple | Past Participle |
|---|---|---|---|
| forecast | forecast / forecasted | forecast / forecasted | forecast / forecasted |
| broadcast | broadcast | broadcast | broadcast |
| cast | cast | cast | cast |
| cost | cost | cost | cost |
Note how these verbs typically do not take an -ed ending.
10.5 British vs. American English: Stylistic Preferences
British English overwhelmingly favors forecast.
American English is more permissive, allowing both but still favoring forecast.
Charts from COCA and BNC support these tendencies.
10.6 Nuances in Meaning or Emphasis
Is there a meaning difference?
Generally, no. Both forms mean the same.
However, some perceive forecasted as:
- More informal or conversational.
- More technical or modern.
- Less traditional.
In most cases, the choice is stylistic, not semantic.
11. FAQ Section
1. Is “forecasted” grammatically correct?
Yes, “forecasted” is grammatically correct as the past tense and past participle of “forecast.”
2. Which is more common: “forecast” or “forecasted”?
“Forecast” is more common and traditional, especially in formal writing. “Forecasted” appears less frequently.
3. Can both forms be used interchangeably?
Yes, both are accepted, but choose one for consistency in a given context.
4. Is there a difference in British and American English preferences?
Yes. British English prefers “forecast,” while American English accepts both but still tends to prefer “forecast.”
5. Is “forecasted” considered informal or incorrect?
It is not incorrect, but some view it as less formal or less traditional.
6. How should I choose which form to use in my writing?
Consider your audience, formality, and regional norms. When in doubt, use “forecast.”
7. Are both forms accepted in academic or professional contexts?
Yes, though “forecast” is usually preferred for formality.
8. Does the tense form change in passive voice sentences?
No, both forms can be used: A storm was forecast / forecasted.
9. Is the pronunciation different between the two forms?
Yes. “Forecast” sounds the same in all tenses. “Forecasted” adds an extra syllable: /-ɪd/.
10. What are some other irregular verbs similar to “forecast”?
Examples include broadcast, cast, cost, cut, put, set, shut.
11. Can I use “forecasted” in perfect tenses?
Yes. Example: They have forecasted rain.
12. Has the usage of “forecasted” increased over time?
Yes, especially in American English and technical fields, but “forecast” remains dominant.
12. Conclusion
To summarize, both “forecast” and “forecasted” are accepted past tense and past participle forms of the verb “forecast.” However, “forecast” is more widely preferred and traditional, especially in formal and British English contexts.
Be consistent in your usage, and consider audience, context, and register when choosing which form to use. Awareness of irregular verb patterns will strengthen your grasp of English grammar and improve your communication skills.
Practice regularly using the tables, examples, and exercises provided in this article. Consult style guides or trusted resources when writing professionally or academically.
Mastering the past tense of “forecast” will help you express predictions clearly and accurately, enhancing your confidence and fluency in English.
Keep learning, keep practicing, and soon, choosing the right form will come naturally!