what is the weather forecast at this time what is the weather forecast
- Before examining why longer-term forecasts are less accurate than current forecasts, timeanddate.com looks at basic definitions on the types of weather forecasts made in relation to time: 1  A short-range forecast is a weather forecast made for a time period up to 48 hours. Extended forecasts are for a period extending beyond three or more days (eg. a three to five-day period) from the day of issuance. Medium range forecasts are for a period extending from about three days to seven days in advance.