While it's still technically winter, temperatures in parts of B.C.'s Lower Mainland reached 20 C Monday.

Following the first relatively warm weekend of the year, even warmer weather led to broken records in some areas.

White Rock was one of the warmest of the record-breaking communities, reaching a high of 20.3 C Monday afternoon. The previous record for March 12 was a full two degrees cooler and set in 1965.

In Pitt Meadows, the mercury reached 19.5 C, breaking a record set 77 years ago by a tenth of a degree. West Vancouver also saw its warmest March 12 on record with a high of 17.6 C, up from 15.9 three years ago.

Outside of the Lower Mainland, temperature records were also broken in Bella Bella (16 C, compared to 13 in 2005) and in Dease Lake (9 C, compared to 8.3 in 1965).

The warmth is welcome after an unusually cold February. It was between 1.5 and two degrees colder than normal in Metro Vancouver last month, Environment Canada said, making it the 15th coldest February on record.

January was warmer than usual, but the province's South Coast was dampened by more precipitation than normal.

Monday's heat will be short lived, however, because rain and cooler temperatures are in the forecast on Tuesday and Wednesday. Environment Canada forecasts another warm weekend, with estimated highs of between 10 and 12 C and a mix of sun and cloud.

While sunbathers embraced the warm temperatures and sunny skies at the start of the work week, the weather has forecasters worried about rising water levels.

"The high snow packs within the South Interior are the highest concern at this point," said the head of the BC River Forecast Centre, Dave Campbell.

"Typically, when we get over 120 per cent of normal snow at this time of year, we get more concerned. And we're up at 135 per cent."

If temperatures consistently hit the mid-20s through April, the melt and any new rain could mean flooding downhill. With spring arriving next week, it's a possibility.

"That ridge of high pressure over the Pacific is intensifying… That's usually an indication that we'll get into more spring-like weather," Environment Canada's Cindy Yu said.

With a report from CTV Vancouver's Breanna Karstens-Smith