Spring officially arrives on Tuesday, but the first 50-degree days of the season may not wait for the calendar.

Temperatures will flirt with 50 degrees over the weekend in the Twin Cities, the National Weather Service said, just in time for one of the biggest party days of the spring: St. Patrick's Day.

Officially, the weather service is forecasting 47 degrees and sun-drenched skies on Saturday, allowing those heading to the St. Paul St. Patrick's Day parade at noon to bask in the warmth of what would be the warmest day of the year. Things may be just a tad cooler — but still mild — by the time the Minneapolis St. Patrick's Day parade starts at 6:30 p.m. on the newly-renovated Nicollet Mall.

The mercury hit 47 degrees two other times this year, on Jan. 26 and Feb. 27, distant memories in what otherwise has been a frigid winter. That mark should be surpassed on Sunday as the weather service is forecasting a high of 49 degrees and optimistic bank thermometers could be blinking 50 degrees or warmer.

Two straight days of temperatures in the upper 40s will do a number on the remaining snowpack, which as of Wednesday had shrunk to a measly 2 inches in the Twin Cities, according to the Minnesota Climatology Office.

A Friday high of 41 degrees will melt more snow away, allowing more bare ground to emerge.

Winter finally waning

Winter looks to be losing its grip after a frigid February that saw temperatures run 5 to 7 degrees cooler than normal. Minnesota reported the coldest temperature in the nation seven times during February — the most of any state in the country — in what was 28th coolest February in 145 years of recordkeeping, said climatologist and meteorologist Mark Seeley.

Despite the cold and snowy winter, surprisingly, one of the first signs of spring actually appeared last week: The first red-winged blackbirds of the season were heard singing last Thursday. That was six days earlier than the median date of March 14, the climatology office said.

And for those ready to bid winter adieu, there is even more good news. Spring's arrival is about a week ahead of average for 2018, according to the National Phenology Network. The network studies plant and animal life cycle events that are influenced by environmental changes, especially seasonal variations in temperature and precipitation driven by weather and climate.

In case you are wondering, no big state tournament basketball tournament snowstorms are on the horizon. A rain and snow mix is possible on Monday and Tuesday nights, the weather service said. After a drop from a high of 41 degrees Monday to a high of 36 degrees Tuesday, it's back to the 40s and dry by the middle of next week, the weather service said.

Tim Harlow • 612-673-7768