Slow motion autumn, peak color, rivers react to climate change

Fall color peak

This is as good as it gets for fall color in the metro. The fleeting 'fall color peak' decorates the Twin Cities this week.

Here's the latest map from the Minnesota DNR.

Edge of frost

Clear skies and light winds are the perfect combination for scattered frost Thursday and Friday morning. The inner metro core may once again hover just above 32 degrees, but frost and even freezing temps will be widespread in the outer suburbs and most of Minnesota. Cover up those last blooms to keep them through the weekend.

Weekend warming trend

Cool Canadian high pressure settles in over Minnesota Thursday. By Friday winds turn south once again. The weekend looks milder, and sunny.

Football weather

Bright late October sun. Crisp mornings and milder afternoons. Still vibrant fall colors on the landscape. This could be the 'last best' weekend of fall.  Highs should make the low 60s in the Twin Cities this weekend.

Slow motion Autumn

Our slow motion descent into fall lingers through at least Monday. The upper air map shows a ridge of mild high pressure lingering early next week.

The Euro hits at another shot of rain by Tuesday and Wednesday of next week.

East coast heat October wave

This week's Midwest record heat wave has shifted east. It's been a long, hot summer for places like Washington, D.C. and New York City.

Minnesota rivers reacting to climate shifts

Earlier this year I had the pleasure to speak with Phyllis Messenger of Open Rivers. We talked about how climate changes in Minnesota are changing the nature of precipitation patterns. The increased volatility in precipitation across Minnesota now often pushes rivers to previously unseen territory.

You can check out more of my conversation here in Open Rivers.

[OR] How does living near the Mississippi River shape you today?

[PH] Our rivers and lakes are a barometer of climate change. We’re seeing much higher volatility in our river systems and our hydrologic cycle. It’s well documented that it’s not raining as often in Minnesota, but when it does, it’s raining harder. That fits with the shift in climate. You increase the vapor in the atmosphere by roughly four or five percent, and you get exponential increases in rainfall when it does rain. I’ll give you an example. In 2013 the Mississippi River level at St. Cloud went from the seventh highest reading to the third lowest reading in just over two months. So we’ve seen this trend toward wetter springs and early summers in Minnesota, toward an increase in early warm season precipitation. And then it shuts off later in the summer. So we’re getting a trend toward these high variabilities in our river levels, where we’re getting record floods in early spring and summer, and then a record drop to low water levels in late summer and early fall. That doesn’t happen every year, but we’re seeing a trend. There is higher volatility in our river systems, and the Mississippi is part of that.

[OR] So that causes some challenges for cities and urban planning and so forth, doesn’t it?

[PH] Indeed it does. City managers around the state are scrambling to deal with that. Our urban infrastructure was built around a certain set of climate assumptions from more than a hundred years ago. Those climate assumptions are no longer valid, especially when it comes to precipitation intensity. The 2012 Duluth flood is a great example of a city being overwhelmed by the kind of extreme weather we’ve been having. We have had four major 1000-year rainfall eventsin Minnesota since 2007. Three of them were in southern Minnesota, one in the Duluth area. That was a $100 million infrastructure damage event in Duluth. Cities all around the area are dealing with these higher water events, where places like Mound, near Lake Minnetonka, were overwhelmed by high water levels. It’s interesting to watch, as climate shifts, even when it seems like our national policy makers are slow to react, our local cities policy makers are well aware of this. They’re on the front lines of climate change and they’re dealing with it every year.