Tobler said: "There is also the chance of some thundery downpours in eastern areas on Wednesday and Thursday, although they will be pretty few and far between".
"A good place to keep the brolly handy will be across northern England, down to Lincolnshire and Yorkshire in the east, where there could be some thundery downpours.
Although the prediction is "odds-on for a barbecue summer" according to the forecasters, the UK can still expect some heavy downpours.
It said that heavy, slow-moving and thundery showers were expected to develop on Monday afternoon, bringing the risk of some torrential downpours, particularly across northern areas.
"Not everywhere within the warning area will see thunderstorms, and indeed some spells of warm sunshine are expected at times, but where thunderstorms do form, some torrential downpours are likely with frequent lightning, large hail and locally strong gusts.
Tim Morrin, a meteorologist with the weather service's Brookhaven office, said two to three more hours of rain was expected, with some heavy downpours, adding as much as a half-inch to accumulations.
Throw in some heavy downpours and a lot of symbolism and it could feel like the beauty of, well, the flowers, is slightly drowned out - literally, in the case of the rain.
Some are cascading downpours, others trickles that wind their way to the sea below.
"Given similar initial weather conditions, we don't know why some storms produce downpours while others contain just as much water vapor but make very little or no rain," Dr. Weisman said.
