Slight Severe Storm Risk

A line of strong storms is developing west of the Twin Cities. This band of strong to potentially severe storms should strengthen through the dinner hours, passing just south of St. Cloud, reaching the metro area between 5:30 and 7:30 pm. Small hail and isolated wind damage is possible, along with a very slight chance of a tornado. Conditions are marginal for tornadoes, but in this kind of a pattern we can't entirely rule out the possibility. Stay alert and check in often for severe weather updates and possible damage reports.



According to SPC, the Storm Prediction Center, much of southeastern and southcentral MN, including the Twin Cities. A few isolated storms may produce 1-1.5" hail and violent winds. An isolated tornado can't be ruled out either. Check in often with mnweathercenter.org/weather and MinnPost.com for updates throughout the afternoon hours. We'll keep you up to date on the risk.


According to SPC, the Storm Prediction Center, much of southeastern MN and southwestern WI is under a "slight" risk of severe storms later today. A few isolated storms, especially south/east of the Twin Cities, may produce 1-1.5" hail and violent winds. An isolated tornado can't be ruled out either. Check in often with mnweathercenter.org/weather and MinnPost.com for updates throughout the afternoon hours. We'll keep you up to date on the risk.


(Thanks to the Minnesota State Climatology Office for providing a wealth of information about weather on Minnesota's most important - unofficial - holiday. If nothing else it will give you something to talk about after you run out of Ole and Lena jokes).

Minnesota's Fishing Opener weather is typified by partly cloudy to cloudy skies, morning temperatures in the low 40's, and afternoon temperatures climbing to near 70. Three out of four years are free of measurable precipitation. A trace of snow has been reported in northern Minnesota on at least four of the last 56 fishing openers. On at least three occasions, some lakes were still frozen for the opener. Generally there is enough wind to be felt on the face, maybe enough to 'fly' a flag. Weather on Minnesota fishing opener dates is highly variable. 56 years of fishing opener weather data are summarized here to offer a glimpse of what is 'typical' and what is 'extreme'.

Opening day temperatures have started as low as 24 degrees at International Falls (1996,2004), with freezing temperatures possible even in Minneapolis (31 degrees in 1979). On the warm side, St. Cloud saw 92 degrees in 1987, Minneapolis reported 91 in 1987, and International Falls reached 88 in 1977. The average early morning temperature varies from the high 30's in the northeast to the high 40's along the southern border. The average afternoon temperature generally ranges from the mid 60's along the northern border, to the low 70's in the extreme south. Along the shore of Lake Superior, highs are held in the mid 50's.

Three quarters of past opening days have been free of measurable precipitation. Two thirds of the fishing openers have been free of any precipitation, measurable or not. On those days with measurable rain, the amounts averaged close to a half-inch in the south and a quarter inch in the north. No amounts over one inch were recorded at either St. Cloud or International Falls, while Minneapolis experienced 1.15 in 1962 and 1.64 in 1965. Snowfall has generally has been limited to traces. Traces of snow were officially recorded in 1963 and 1993 at International Falls, and in 1968 at St. Cloud. A tenth (.1) of an inch fell at International Falls in 2000.

Statewide, less than one year in five offers totally clear skies. The average amount of cloudiness lies near that fuzzy boundary between 'partly cloudy' and 'cloudy', but over half of the dates were classified as cloudy.

Average daily wind speeds generally range between 8 and 15 miles per hour. This range can is described as 'wind felt on face ...' to '... wind extends light flag'. The predominant wind direction is split fairly evenly between blowing from the northwest, south, and east.

Fog has been reported on the fishing opener, occurring about one year in ten in the south, about one year in six in the north. By early to mid May, Minnesota is entering its thunderstorm season. The possibility of thunderstorms is greatest in the south (about one in seven), less in the north (about one in eleven). The weather should be monitored carefully if the skies appear threatening.

Weather Headlines

* Slight severe storm risk over southeastern MN, including the Twin Cities: potential for 1-1.5" hail, damaging winds, even an isolated tornado - best chance between 5 and 7 pm.

* A few Tuesday T-storms turn severe east of the Twin Cities metro with hail up to 1" in diameter (nickel size) reported in Washington County. Severe storm warnings were posted for western Wisconsin for hail and damaging winds.

* 72 degree high in the Twin Cities Tuesday, .20" of rain falls. Nearly .50" soaks the Duluth area from today's frontal passage.

* Wednesday: last lukewarm day this week, low 70s likely.

* 1 in 3 chance of bumping into a late-day shower or T-storm Wednesday afternoon.

* Cooling into the upper 50s to near 60 later this week.

* Sunday now appears to be the drier, brighter day of the weekend.

* We seem to be entering a wetter pattern in general: more frequent showers, many farms/lawns pick up .50 to 1" of rain in the next 7-10 days.

* 70s may return by the middle of next week.

Fishing Opener Update

I know the weather flip-flop is annoying. It makes us crazy too, believe me. Not to blame "the pattern" but the jet stream is howling overhead (one reason why the winds at the surface have been so persistent in recent days). This also means rapid weather changes, which makes the concept of a 7-Day Outlook even more problematic than usual. The latest computer run hints at just enough instability for a few hours of showers on Saturday. I still don't think it will be an all-day washout, but you would be well advised to a). take a jacket, and b). make it waterproof, while you're at it. Sunrise temperatures start in the low 40s with "high" ranging from near 50 at Leech Lake to 54 at the Whitefish Chain, Gull, Pelican and North Long Lake, closer to 56 at Mille Lacs, and if the sun stays out for a few hours (likely) the mercury may brush 60 on Lake Minnetonka and White Bear Lake, where Gov. Pawlenty will be trying his hand at a trophy walleye. We've seen worse, true, but don't count on a picture-postcard-perfect Fishing Opener. Hey, why should this year be any different?

Paul's Column

O.K. Paul. Level with me. Tell me the truth. Put your remote control down, step away from the Doppler and come clean. Why. WHY?? does it always tend to rain on weekends, especially holiday weekends? Is it my imagination? I swear I'm more likely to get soaked on a weekend, when I'm mowing the lawn or loitering up at the cabin, than on a Monday or Tuesday, when I'm stuck in my dark, little cubicle. What the heck is going on here?

Great question: keep in mind that on the weekend more of us wander outside, more of us are outdoors, at the mercy of the elements, more "weather-sensitive" than we might be during the work week, when the weather floating overhead is often ignored, usually irrelevant (unless you're trying to schedule after-school ball games!) That's one reason why it SEEMS like weekends tend to be wetter than weekdays. However, there may be a shred of scientific evidence that rain is more likely to fall on a weekend than Monday through Friday. It turns out pollutants from daily commutes, millions and millions of them, can "seed" clouds with fine particles of dust, necessary for raindrops to form, increasing the probability of showers and thunderstorms, especially during the spring, summer and fall months. The theory isn't foolproof, and this "man-made cloud seeding" effect seems to be more prominent in the data the farther east you live in the USA, so it's a bit of a hand-waving argument to say this is why it seems to rain more on weekends here in Minnesota. Yes, it is possible nudge Mother Nature in one direction or another, we are impacting weather on a local and global scale, without even realizing it.

The atmosphere in May is usually quite unstable, warming rapidly near the ground and still plenty cold thousands of miles above the surface of the earth. This imbalance (cold air wants to sink, warm air wants to rise) leaves the atmosphere irritable, unstable, capable of turning a thermal of warm, rising air into a towering thunderhead when enough moisture is present. Yesterday conditions for storms were marginal: most of the T-storms blossomed over the south and east metro, storms spitting 1" hail in Washington county, east of St. Paul. Warnings had to be issued near Duluth and west central Wisconsin for nickel-size hail. Today may be a carbon-copy of yesterday with morning sun, clouds sprouting in the afternoon, and a few hit-or-miss thunderstorms flaring up after 3 or 4 pm. Most of Wednesday looks dry, in all probability the last shirt-sleeve day this week with highs topping 70.

A northwesterly wind kicks in later in the week, cooling us down to jacket levels Thursday and Friday. Showers will linger over northern Minnesota (especially Thursday) but Friday looks fairly dry, statewide, so getting off to your favorite lake should come up without any atmospheric drama. Saturday's on-again, off-again shower risk seems to be on-again, unfortunately. A lingering whirlpool of chilly air several miles above Minnesota will create a damp brew capable of a few hours of showers Saturday, especially midday and afternoon hours, but I don't think we'll be subjected to an all-day rain. That said, lug along something warm and waterproof. Sunrise temperatures start out near 40 up north, with highs stuck in the upper 40s near Thief River and Leech Lake. Minnesota's most popular fishing lakes (Gull, Whitefish Chain, Mille Lacs) will see highs in the low to mid 50s with a light breeze (under 15 mph). Expect a healthy walleye chop and a steady barometer, conditions that won't hurt your odds of catching fish. It won't be the most comfortable Fishing Opener we've seen in recent years, but it could be worse. I remember some years with ice pellets, horizontal rain and severe wind chill. Nothing quite that extreme this time around.

The news is good for farmers and anyone with a backyard garden (or lawn you're trying to keep green). We are definitely in a wetter pattern, the boundary separating hot air to the south and chilled Canadian air to our north setting up directly over Minnesota. That should mean frequent showers and storms, with 2-3 days of rain on tap for next week. After a cool weekend temperatures recover a bit next week - more 70s possible by the middle of next week.

So there you have it: a possible explanation why it may, in fact, rain a little more on weekends than weekdays, a so-so Fishing Opener, news of of a jacket rerun this weekend, and a significant puddle potential lasting into all of next week. We'll keep tweaking (is that a real word?) the all-important Fishing Opener Outlook. Hopefully the news will get better as the week goes on.