good, optimistic
gloomy, pessimistic
conservative
accurate, correct
detailed
revised
annual
early
long-range, long-term
a long-range weather forecast

short-term
a short-term forecast of the economy

local
official
economic, financial, market, shipping (BrE) (shipping news in AmE), weather
cash-flow (esp. BrE), earnings, growth, inflation, profit, revenue, sales

prepare, produce
give, issue, make, provide
The government has issued a pessimistic economic forecast.

revise, update
lower, raise
This week the company is expected to raise its revenue forecast.

rely on
check
Check the weather forecast before you set out.

be in line with
The interest rate is in line with the forecast.

call for sth (AmE), predict sth, say sth, suggest sth
This morning's weather forecast called for snow.
Some forecasts suggest that the increase in heart disease will continue for some time.

assume sth
be based on sth
forecasts based on a complicated procedure

forecast about
Forecasts about the economy are often misleading.

forecast for
forecasts for earnings in 2015

forecast of
forecasts of population growth

accurately, correctly
originally, previously
higher costs than those originally forecast

be difficult to, be hard to

Forecast is used with these nouns as the object:
demand, future, rain, return, weather