Cool start, then March turns quite mild

Cool start, then March turns quite mild:

After starting the month with cooler than normal temperatures (many subzero mornings in the north over the 1st and 2nd), March produced quite a series of warm days this week. Most climate stations have reported daytime highs in the 40s F for the middle and end of this week, and over 60 climate observers have reported readings of 50°F or greater. In many areas nighttime temperatures were kept well above normal for this time of year because of the formation of fog, which took a while to burn off each morning.

After a dry start to the month, forecasts continue to favor chances for rain on Friday, and some rain/snow early Saturday, as temperatures cool down a bit. It will also be breezy over the weekend. Then a dramatic warm up on Monday and Tuesday when many areas may see 50°F temperatures again, may be even a few 60°F temperatures. Then a more pronounced cool down for later next week, some cooler than normal days with chances for rain/snow, but no return to subzero readings.

The early spring precipitation indicated in the forecast for the coming week will be welcome, especially in areas of north-central, northeastern, and southwestern Minnesota where Moderate Drought is in place. The landscape is beginning to thaw with the warm temperatures, along with the lack of snow cover, and will take in the precipitation to recharge soil moisture. In fact, snow cover, is absent over the southernmost 60 percent of the land surface now.

We must remember that rollercoaster temperature patterns in March are not uncommon, as the statewide extremes illustrate with 88°F high temperatures in 1910 and 2007, and -50°F low temperatures in 1897!

Weekly Weather Potpourri:

On Thursday this week, the BBC Weather Center reported that many central and southeastern climate stations in the United Kingdom were reporting their highest temperatures of the year so far. There were many reports of afternoon temperatures between 63°F and 66°F. The early season warmth has brought an early flush of pollen from some trees, especially Alder, Hazel, Cypress, and Elm. The UK Met Office has reported research that show the season release of pollen by Cypress trees is now on average about 10 days early than decades ago. This is driven by measured climate change.

A recent paper in the journal Science Advances documents that wildfires in northern boreal forests may be releasing more carbon dioxide back into the atmosphere than previously thought. Both satellite based measurements as well as field based measurements of emissions suggest that more carbon release may be coming from the burning of peat soils underlying the boreal tree canopies. This study may help climate researchers derive new scales of emission measurements for climate modeling.

An article in this week’s AGU-EOS Bulletin describes the huge loss of ice in Antarctica over the past 30 years. Most of this loss has occurred in West Antarctica, the Antarctic Peninsula, and portions of southern East Antarctica, amounting to roughly 5000 square miles of ice.

MPR listener question:

How many minutes of daylight are gained during the month of March and how much does the sun angle change?

Answer:

Locally, for the Twin Cities, we gain over 1.5 hours in daylength during March. The sun's maximum daily elevation angle above the horizon changes by roughly 11 degrees, from 38 degrees above the horizon at midday on the 1st to 49 degrees above the horizon at midday on the 31st. Don’t forget to advance your clock by one hour this Saturday night (March 7) when we switch over to Daylight Savings Time.

Twin Cities Almanac for March 6th:

The average MSP high temperature for this date is 37 degrees F (plus or minus 11 degrees F standard deviation), while the average low is 21 degrees F (plus or minus 12 degrees F standard deviation).

MSP Local Records for March 6th:

MSP records for this date: highest daily maximum temperature of 69 degrees F in 2000; lowest daily maximum temperature of 6 degrees F in 1932; lowest daily minimum temperature of -16 degrees F in 1890; highest daily minimum temperature of 44 degrees F in 1983, and record precipitation of 0.97 inches in 1983. Record snowfall for this date is 7.0 inches also in 1900.

Average dew point for March 6th is 15°F; the maximum dew point on this date is 55°F in 2017 and the minimum dew point on this date is -18 degrees F in 1955.

All-time state records for March 6th:

The state record high temperature for this date is 77 degrees F at Marshall (Lyon County) in 2000. The state record low temperature for this date is -41 degrees F at Embarrass (St Louis County) in 1996. The statewide record for precipitation on this date is 2.50 inches at Austin (Mower County) in 2006. A record 18.8 inches of snow fell at Collegeville (Stearns County) on this date in 1908.

Past Weather:

With 20 to 30 inches of snow cover across much of the state, an Arctic high pressure system brought record cold temperatures to many communities on March 6 of 1955. Subzero readings dominated over most counties. Morning lows of -30°F or colder were common across northern counties. Thief River Falls (Pennington County) only reached a daytime high of -7°F.

A winter storm brought heavy snowfall to southeastern Minnesota over March 5-6 of 1959. Many climate stations reported 8 to 16 inches of snow winds blew the snow into huge drifts. Many areas schools were closed on Thursday and Friday of that week. Spring Grove in Houston County reported nearly 18 inches of snow.

Spring fever was in the air on March 6 of 2000. There was little or no snow on the ground, bright sunshine, and south winds that brought record-setting high temperatures to most areas of the state. Many climate stations reported temperatures in the 60s F, while weather observers in 40 counties reported readings of 70°F or greater. Some farmers were seen tilling soils.

Outlook:

A breezy weekend is coming up, with cooler temperatures and perhaps some lingering rain or snow showers on Saturday morning. Warmer in the southern areas of the state on Sunday and Monday, then Tuesday will bring a transition to cloudy conditions with chances for rain/snow continuing into Wednesday. Temperatures will be much cooler for Thursday and Friday of next week with chances for rain/snow in some areas.