Minnesotans must have payed it forward in a big way lately. Our incredible run of good weather karma is about to get even better. Fire up the hiking boots, boat, bicycle, golf clubs and backyard grill. The weather stars are aligning one more time for another glorious Minnesota weekend. Leaf peepers rejoice.

Fall color on lake Minnetonka. Paul Huttner/MPR News

Indian summer: A period, in mid- or late autumn, of abnormally warm weather, generally clear skies, sunny but hazy days, and cool nights.

In New England, at least one killing frost and preferably a substantial period of normally cool weather must precede this warm spell in order for it to be considered a true “Indian summer.” It does not occur every year, and in some years there may be two or three Indian summers.

The term is most often heard in the northeastern United States, but its usage extends throughout English- speaking countries. It dates back at least to 1778, but its origin is not certain; the most probable suggestions relate it to the way that the American Indians availed themselves of this extra opportunity to increase their winter stores.

The comparable period in Europe is termed the Old Wives’ summer, and, poetically, may be referred to as halcyon days. In England, dependent upon dates of occurrence, such a period may be called St. Martin’s summer, St. Luke’s summer, and formerly All-hallown summer.

Yes, this weekend probably fits the American Meteorological Society definition of Indian Summer around most of Minnesota. We’ve avoided a frost inside the metro core, but many metro suburbs have already reported the first frost. And since meteorological summer began September 1st, we’r definitely into mid-autumn by now.

It’s been an incredible run of amazing weekend weather across Minnesota. By my count this will be the 7th weekend in a row with abundant sunshine, little rain and warm or pleasant temperatures.

We are leading charmed weather lives these days in Minnesota.

National Weather Service Chanhassen, MN Weather Story Graphic

First a little much-needed rainfall. Our next weather-maker is a moderate low pressure system, a Category 2 on a hypothetical scale of 1 to 5.  The low drags shower bands through Minnesota as it rolls through Wednesday night into Thursday.

Loop of the short range forecasts

Skies start sunny Wednesday. Here’s a more detailed breakdown of expected shower timing for the metro. Wednesday night after dark into Thursday morning is the most likely window for showers. Some sun should return by Friday afternoon.

Weatherspark – NOAA GFS data

Indian Summer weekend

The maps don’t get much better than this for mid-October. Considering the average date of the first metro frost is October 7th, 80 degrees on October 11th is remarkable. Yes, I gave it a 75% chance that our last 80 was on September 27th. Note to self: Don’t bet against the Ultra Glorious Summer (and fall) of 2015.

Here’s the weekend breakdown. I think these numbers are a few degrees too conservative Sunday. 80 degrees looks likely Sunday afternoon in the metro. The average high Sunday in the metro? 61 degrees.

Weatherspark – NOAA GFS data

Longer than average growing season

The 30-year average length of the growing season at MSP Airport is 167 days according to the Minnesota Climate Working Group.


This year our last 32 degree temp at MSP Airport was recorded on April 23rd when we bottomed out at 29 degrees. The first frost looks to be at least October 16th this year. That’s likely at least 175 days between freezing temps at MSP.

NOAA GFS data via IPS Meteostar

The trend of longer growing seasons is clear in the Midwest.

As forecast models continue to grapple for consensus on the eventual track of Hurricane Joaquin, there is a growing trend. Most of the models seem to be coming more into agreement with the ECMWF model’s notion of an easterly track that keeps the powerful and dangerous hurricane out to sea and away from the US coastline. It’s still too early to be sure the US will avoid a direct hit from Joaquin, but a distinct shift in that direction has occurred. Read more