The Past Tense of 'Forecast' Is Easy — the Numbers in the News Report Are Where You Lose Points

You're doing a dictation listening exercise on a weather bulletin. The announcer reads it straight through, you write down "Rain is forecasted for Thursday, with a high of thirteen", and the answer key marks two spots in red. The actual sentence is "Rain is forecast for Thursday, with a high of thirty". One mistake is that you added an -ed ending yourself; the other is that you misheard the number. Quick answer first: the simple past of forecast is forecast, and the past participle is also forecast. All three forms are written exactly the same.

But the real difficulty of forecast isn't like other verbs in its family. It's a word that almost always shows up next to a number, and the number is where you actually lose points. Weather bulletins and financial news are the two types of content read fastest in spoken English, because the reader has to cram a lot of data into a short time slot. In that stream of speech, thirteen and thirty, sixteen and sixty, and even the phrase "is forecast to" all pile on top of each other into a string of sound that's very hard to pick apart.

This article works through that whole string: the form table for forecast and why it doesn't change, the fact that forecasted is alive and well in finance circles even though it's still not the safe choice, where forecast differs from predict and estimate, listening practice with numbers read at bulletin speed, fixed phrases in weather and in reports, and the most repeated mistakes.

• The form table for forecast, and why it inherits the way cast is conjugated
• What tense forecast is in, and how it differs from predict and estimate
• Listening to forecast and the numbers in fast-read bulletins
• Common phrases with forecast in weather and in reports
• Mistakes Vietnamese speakers commonly make with forecast
• Quick exercises
• Frequently asked questions

The form table for forecast, and why it inherits the way cast is conjugated

Five forms, and three of them are the same string of letters. The phonetic transcription reflects American pronunciation, with British pronunciation noted where the two diverge.

forecast is a compound word: fore, meaning before, plus cast, whose original meaning is to throw. Put together it means to throw forward, that is, to fling a judgment out toward the future. In English, a compound word is conjugated according to the verb sitting at its end, with no meaningful exceptions. cast doesn't change form, so forecast doesn't change form. The same mechanism applies to overcast, recast, typecast, and to a different group too, like understand conjugating according to stand or overtake conjugating according to take.

The group of verbs that don't change form also includes put, cut, hit, let, set, shut, cost, hurt, burst, split, spread, quit and read. The shared trait is visible right away: most of them already end in the sound /t/ or /d/, and English avoids stacking another /t/ on top of that.

Now here's where forecast splits off from its relatives. forecasted is far more common than casted, and it's common in one very specific place: financial writing, corporate reports, statistical documents. You'll find "forecasted revenue", "the forecasted growth rate", "we forecasted a decline" on the slides of a great many large companies. Part of the reason is that in that field, forecast is used as a noun so often that writers need a form that clearly reads as a verb, and -ed gives them that. Major dictionaries do list forecasted as a variant.

Being listed doesn't mean it's safe. In exams, in weather bulletins, in carefully edited writing, the un-suffixed form forecast is still the one nobody can fault. The practical rule is the same as with broadcast: recognize forecasted when you encounter it, and write forecast when you're writing it yourself. Two close relatives worth looking at at the same time, since each leans a different way: the past tense of broadcast has the same debate, but it flares up in streaming contexts rather than finance; and the past tense of cast is the root verb of the whole family, and there the form casted is still considered flat-out wrong. A third relative worth looking at is the past tense of cost, since cost also doesn't change form and also lives thick in sentences full of numbers. The article on English grammar sorts tenses and verb groups into their proper places, which is useful when you want to review the whole system.

What tense forecast is in, and how it differs from predict and estimate

The simplest principle: when all three forms are identical, the tense of the sentence sits in the word before forecast, not in forecast itself. And for this particular word, the structure you'll meet most is not active but passive: is forecast, was forecast, has been forecast, is forecast to.

The last row is the one you should learn as a single chunk. "be forecast to" plus a bare infinitive is how financial news talks about anything about to happen: are forecast to rise, is forecast to fall, are forecast to slow. Hearing that whole chunk as one unit is much faster than parsing it word by word.

The second part of this section is about meaning. Vietnamese lumps forecast, predict, project, estimate, expect and anticipate together around the words "dự báo" and "dự đoán", so when you write, you often pick the wrong one. The six lines below pull them apart.

The most important gap to remember in the table is between forecast and estimate. forecast always points forward in time. estimate doesn't: you estimate the cost of something currently underway, you estimate the number of people in a room, both in the present. Mixing up these two makes your sentence talk about the wrong point in time, not just the wrong shade of meaning.

One more detail that's often overlooked: forecast as a noun shows up more often than forecast as a verb. "the weather forecast", "the sales forecast", "a gloomy forecast". When it's a noun, the stress falls squarely on the first syllable and the whole phrase tightens up; when it's a verb, the two syllables are more even, and some speakers even push the stress onto the second syllable. Catching that shift is the fastest way to tell whether you're hearing the noun or the verb.

Listening to forecast and the numbers in fast-read bulletins

This is a section unique to forecast, and no other page on verb conjugation has it. Weather bulletins and financial news are read faster than ordinary conversation because the reader has to pack a lot of data into a fixed time slot. In that flow, the word forecast itself gets compressed, and the numbers standing next to it get compressed even harder.

The final /st/ cluster drops the /t/ sound before a consonant. "forecast for Thursday" comes out as "forecas' fer Thursday". "forecast rain" comes out as "forecas' rain". When the /t/ sound disappears, forecast and forecasts sound almost the same, because the /sts/ cluster gets reduced the exact same way.

The phrase be forecast to compresses into a single three-syllable block. "are forecast to rise" comes out as "er forecas-tuh rise". The word are is reduced to just an /r/ sound, to is reduced to just a schwa, and the final /t/ of forecast links straight into it. Transcribing this word by word here is a guaranteed miss.

teen and ty are the pair that costs the most points in number-heavy bulletins. thirteen has the stress on the second syllable and ends in the /n/ sound. thirty has the stress on the first syllable and ends in a vowel, with the /t/ in the middle usually turning into a tap that sounds close to /d/, coming out as "thur-dy". When the sentence runs fast, stress is a more reliable clue than the final consonant.

Ordinal numbers and cardinal numbers stick together at the tail end. "the twenty-eighth" and "twenty-eight" differ by only one very light /θ/ sound, and that sound is often swallowed before a consonant. "on the twenty-eighth, temperatures" comes out as one continuous run with no clear place to cut it.

The units that follow a number get reduced almost to the point of vanishing. degrees comes out as "degreez" with a soft /d/, percent comes out as "present" or "prsent", millimetres in a British accent comes out fused into one block, "millimeeters". You catch the number but lose the unit, and the sentence you transcribe ends up with a completely wrong meaning.

forecasting shortens its -ing ending to -in. "They are forecasting a mild winter" comes out as "they're forecastin a mild winter". When both are and the -ing ending shrink, the continuous tense ends up sounding a lot like the simple past.

Below are sample sentences, along with the actual sound and the common mistranscription. The middle column isn't standard phonetic spelling — that's the sentence's real-world sound.

Looking at the third column, the mistakes split into three types. Line one and line three are grammar-reflex errors: the ear doesn't hear any ending at all, but the hand tacks on -ed or -ing anyway because your mind is trying to force a tense onto the sentence. Line two and line five are number-stress errors: you hear all the sounds just fine but put the stress in the wrong place, and with the teen versus ty pair, the stress is the entire piece of information. Line four and line six are function-word errors: has been and the get swallowed, so the whole sentence structure changes. These three types call for three different fixes, and knowing which type you're dealing with matters more than getting one single sentence right.

In a dictation session on WELE, this sequence plays out very concretely with sentences that contain numbers. You transcribe the sentence exactly as you heard it, the scoring flags precisely the word that's off, and with forecast, what gets marked wrong is very often a number, not the verb. That's a piece of information that reading a verb conjugation table will never give you: you hear the whole sentence, you understand the whole sentence, but the one number carrying the actual information is the one you get wrong.

The correction loop that follows is very short, and very different from relearning grammar. You listen to that same sentence again, this time paying attention only to where the stress falls in the number rather than to the final consonant. Weather bulletins are the best kind of content for practicing this because they're tightly framed: there's always a forecasting verb, a date, a number and a unit. Once the pattern repeats often enough, your ear starts to anticipate where a number is about to come, and anticipating it is half of hearing it correctly.

These sounds don't disappear because your listening is weak, and the article on connected speech explains the mechanism of sound-dropping and linking across whole sentences. The real sentences live in the podcast library, with transcripts included for you to check against.

Common collocations with forecast in weather and reports

forecast doesn't produce phrasal verbs. There's no forecast up, no forecast out. What it does produce are fixed collocations, and they split into two clear groups: the weather group and the business-figures group. The thirteen lines below are written in the past or participle form so you get used to seeing them that way.

There's a detail worth noting in the line "as forecast". It's a reduced clause, in full "as it was forecast", and precisely because it's reduced, it ends up as just two syllables stuck onto the end of the sentence. In a bulletin, this phrase falls right where the voice is dropping, which is the easiest spot to miss. Miss it, and you lose the whole point that the thing had been announced ahead of time.

One more detail about tense. "Rain was forecast for Thursday" talks about a forecast that was issued in the past, and implicitly suggests that either Thursday has already passed or the forecast is old. "Rain has been forecast for Thursday" talks about a forecast that's still valid right now, and Thursday hasn't come yet. Because forecast doesn't change form, the only thing that tells the two sentences apart is the has been sitting in front of it — which happens to be exactly the part most likely to get lost in fast speech.

Mistakes Vietnamese learners commonly make with forecast

forecasted in exams and in bulletins. This is the most common mistake, and it has a solid reason behind it: you see forecasted in company slides, in reports, in financial writing, so you assume it's the standard form. In that context, it gets by. In exams, in weather bulletins, in carefully edited writing, the ending-less form forecast is the safe one. Write forecast.

is forecasting instead of is forecast. After is, was, are, were, been, what follows must be a participle. "Rain is forecast for Thursday" is correct. "Rain is forecasting for Thursday" is wrong, because that sentence says the rain itself is out there doing the forecasting. This mistake shows up when you want to stress that something is happening right now and you reach for the -ing ending.

Using forecast for a guess with no data behind it. forecast implies there's a model, there are figures, there's a basis for it. When you're just guessing at random or going on a hunch, the right word is predict or guess. "I forecast that he will be late" sounds very odd; the natural sentence is "I bet he will be late" or "I predict he will be late".

Confusing forecast with estimate. forecast points toward the future; estimate approximates a current figure that hasn't been measured precisely yet. "We estimated the damage at two billion" talks about damage that has already happened. "We forecast damage of two billion" talks about damage that hasn't happened yet. Pick the wrong one and your sentence gets the timing wrong too.

Dropping the article before forecast when it's a noun. It's "the weather forecast" or "a forecast," rarely bare forecast. The sentence "Forecast says it will rain" sounds incomplete; the natural sentence is "The forecast says it will rain." This is a mistake that's easy to spot on a re-read but hard to catch yourself while speaking.

Transcribing forecasts as forecast when listening. The /sts/ cluster at the end of forecasts gets reduced so much that it barely creates a new sound at broadcast speed. The only clue is the subject and the time context: "The model forecasts a mild winter" is simple present with a singular subject, so it must have the s. This is an error of the ear, not of grammar memory, and the fix has to be relistening too.

Quick exercise

Eight sentences, fill in forecast, forecasts or forecasting. Check against the answers below only after you've finished all of them.

1. Heavy rain is ______ for the central provinces tomorrow.
2. The model ______ a mild winter every year, and it is usually right.
3. They ______ a storm three days before it arrived.
4. Snow has been ______ for the weekend, so pack a coat.
5. Did the agency ______ anything about wind?
6. Analysts are ______ a slow first quarter.
7. Prices are ______ to rise by about four percent.
8. The typhoon reached the coast on Tuesday, as ______.

Answers: 1. forecast. 2. forecasts. 3. forecast. 4. forecast. 5. forecast. 6. forecasting. 7. forecast. 8. forecast.

Sentences 2 and 7 are the two worth pausing on. Sentence 2 is simple present with a singular subject, so it needs the s, and if you filled in forecast it's usually not because you forgot the rule, but because your ear is used to the /sts/ cluster being swallowed in speech. Sentence 7 is the phrase be forecast to, a fixed chunk you should remember whole rather than piece together, because in broadcasts it always comes out in one breath. If you got these two wrong, the section above is worth reading again.

Frequently asked questions

What is the past tense of forecast?

The simple past of forecast is forecast, and the past participle is also forecast. All three forms are written identically because forecast is a compound of fore and cast, and cast doesn't change form.

Is forecasted wrong?

Not exactly wrong, but not the one to choose. forecasted shows up a lot in financial texts and corporate reports, and major dictionaries do list it as a variant. In exams, in broadcasts and in carefully edited writing, the ending-less form forecast is still the safer choice.

How is forecast different from predict?

forecast implies there's data and a model behind it, and it usually comes with a figure and a timeframe. predict is just guessing a result in advance, which can be based on experience or a hunch, with no need for a computational basis. A weather station forecasts, while someone sitting and watching a football match predicts.

Why do people often mishear numbers in weather broadcasts?

Because the teen/ty pair differs only in where the stress falls, and broadcasts are read faster than ordinary conversation. thirteen is stressed on the second syllable, thirty is stressed on the first syllable and has the middle /t/ turn into a tongue tap. When the sentence runs fast, stress is a more reliable clue than the final consonant.

Is forecast a noun or a verb?

Both, and in practice it functions as a noun more often. As a noun it takes an article or a preceding noun: the weather forecast, a sales forecast. As a verb it doesn't change form in the past, and it often appears in the passive: is forecast, was forecast, is forecast to.

How long does it take to learn forecast well enough to understand weather broadcasts?

You can master the rule part in ten minutes, since the three forms are identical. The ear part depends on your current listening level, and what you need to practice isn't the verb itself but the numbers and units standing next to it. After a few weeks, what you can compare against is your result on the listening level test.

You can read through the forecast forms table in fifteen seconds because the three lines are written the same way, and that's the easiest part of this page. The rest — the fact that thirteen and thirty differ by only one stress placement and the whole sentence changes meaning because of it — only really sinks into your ear once you miss it in transcription and see the number you got wrong. Pick a short weather bulletin and try dictation listening practice on a few sentences with is forecast, then go back to the table at the top of the article and see if it still looks obvious.