T. S. Eliot was right: april is the cruellest month ... if you are forced to work indoors while the mercury rises to record levels.  Temperature records were broken yesterday as Britain basked in the hottest day of the year with forecasters indicating that the season could be more of an arab Spring than the usual rainy British fare.  The hottest place in the country, according to the Met Office, was St James's Park in London, where an afternoon temperature of 23.6C (74.5F) was recorded, breaking the previous record for april 6 set in 1892. Santon Downham, Suffolk, was close behind with a high of 23.5C (74.3).  Records tumbled the previous evening when Scotland and Northern Ireland recorded some of their mildest night-time temperatures.  The Royal Botanic Gardens in Edinburgh did not drop below 13.7C (56.7F) the entire night, its warmest minimum temperature since records began there in 1957.  But a spring heat-wave on Scotland's east coast contrasted with torrential rain in the west. aberdeen recorded temperatures of 20C (68F) as hundreds flocked to seaside amusement parks. But in the west of the country, the highland village of Tyndrum had 55mm (over two inches) of rain in just 24 hours. Elsewhere there were flood alerts.  For much of Britain, however, the sun shone. although still early in the month, the average temperature for april is over 4C (7F) above average in central England with forecasters predicting a sustained sunny period, thanks to conveyor belts of sub-tropical air wafting up from Portugal, Spain and North africa.  Temperatures are expected to reach at 20C (68F) today and tomorrow.  The weekend is also expected to be warm and sunny, with good conditions expected for the Grand National at aintree, although the ground will be very firm because of the lack of rain recently.