Air Quality Alert Through 6 AM Thursday

Air quality has once again deteriorated across the state behind a front that has stalled out across portions of Minnesota as wildfire smoke filters in. This smoke has made it down to the ground, and air quality levels in north-central reached hazardous levels Tuesday. An Air Quality Alert is now in place across a good portion of Minnesota through 6 AM Thursday, including the Twin Cities, Rochester, Duluth, International Falls, and Bemidji. You can read more from the Minnesota Pollution Control Agency by clicking here.

_______________________________________________

Wednesday Weather Outlook

The haze continues across the sky as we continue into Wednesday due to the wildfire smoke filtering through the region. Otherwise, partly sunny skies can be expected. I don't think we can rule out an isolated shower or thunderstorm in the afternoon, but chances would be better in northern Minnesota. Highs will top off in the mid to upper 80s.

The best chance of showers and thunderstorms on Wednesday will be across northern Minnesota with a system passing through, but in the vicinity of a stalled boundary across central/southern Minnesota a random shower or storm could be possible. Otherwise, hazy and partly sunny skies are expected with highs ranging from the 60s along the North Shore to the 90s in western Minnesota.

_______________________________________________

Hot Weather Continues

The heat will continue to bake the region as we head through the end of the week into the weekend, with highs mainly in the 90s expected.

Dew points will also be on the rise later in the week, with max dew point values up near 70F by Friday and Saturday. That will lead to heat index values climbing into the upper 90s, which may spark some Heat Advisories.

_______________________________________________

Best Upcoming Rain Chance: Late Friday/Friday Night

After we get past a rain chance Tuesday night in the Twin Cities, the next best chance will be late Friday into early Saturday as an area of low pressure moves through the upper Midwest. However, the best chances of this rain still appear to be across northern Minnesota into portions of Wisconsin - particularly north of the I-94 corridor.

_______________________________________________

No End To Drought In Sight

Unfortunately, it does not appear there is an end to our drought conditions in sight. In fact, the latest Seasonal Drought Outlook issued by the Climate Prediction Center on July 15th shows drought persisting across much of the state through the end of October.

This graphic, also courtesy of the Climate Prediction Center, shows how much rain would be needed in the next four weeks to essentially bring an end to the drought. The least amount of rain would be needed in southeastern Minnesota where only 3-6" of rain would be necessary. Across portions of central and north-central Minnesota, 9-12" of rain is required.

_______________________________________________

Tornado Warning Drought

We are not only going through a moisture drought but another drought that we are a little happier about: a tornado drought. The Twin Cities office (shown in the first image) has only issued 11 Tornado Warnings so far in 2021. Only nine times since 1986 has the Twin Cities office issued fewer than 11 Tornado Warnings through approximately July 20th, the most recent being in 2018. Statewide, only 11 Tornado Warnings issued so far this year, the fewest since 2013. There have only been four other years since 1986 that 11 or fewer Tornado Warnings have been issued statewide through mid-July. Graphics above courtesy of the Iowa Environmental Mesonet.

_______________________________________________

Setting Weather and Climate Expectations
By Paul Douglas

We expect perfection in an imperfect world. That applies to increasingly extreme weather and climate events. Meteorologists in Germany are under fire for not predicting the 2 month's of rain that fell in 2 days. Recently meteorologists gave nearly a week's notice that historic heat would grip the Pacific Northwest. Wildfires, like the LA-size blaze making its own weather in Oregon? Like a bear in the woods - they go where they want to go.

In general: 10 minute lead time for tornadoes, 1-3 hours for flash flooding, 1-3 days for river flooding and as much as 2-4 days for reliable hurricane track forecasts, but predicting hurricane intensity is still very tricky in a warming world.

Speaking of warming, low to mid 90s will be the rule into next week. This latest heat wave will be washed down with wildfire smoke, but any thunderstorms along the leading edge of simmering heat will be few and far between. No widespread soakings.

ECMWF predicts 100-degree heat at MSP next Tuesday and Wednesday. Even hotter than June.

_______________________________________________

Paul's Extended Twin Cities Forecast

WEDNESDAY: Smoky sunlight. Wake up 68. High 88. Chance of precipitation 20%. Wind SE 7-12 mph.

THURSDAY: Hot sunshine. Wake up 72. High 91. Chance of precipitation 10%. Wind S 10-20 mph.

FRIDAY: Sunny, hot and sweaty. Wake up 74. High 95. Chance of precipitation 10%. Wind S 10-20 mph.

SATURDAY: Early T-storm, then clearing. Windy. Wake up 72. High 93. Chance of precipitation 40%. Wind NW 10-20 mph.

SUNDAY: Plenty of sunshine, lake-worthy. Wake up 68. High 92. Chance of precipitation 10%. Wind SW 8-13 mph.

MONDAY: Sticky sun, stray T-storm. Wake up 72. High 91. Chance of precipitation 30%. Wind SE 8-13 mph.

TUESDAY: Sunny, heat spike possible. Wake up 75. High 100. Chance of precipitation 10%. Wind SW 10-20 mph.

_______________________________________________

Minneapolis Weather Almanac And Sun Data
July 21st

*Length Of Day: 15 hours, 4 minutes and 29 seconds
*Daylight LOST Since Yesterday: 1 minute and 56 seconds

*When Do We Drop Below 15 Hours Of Daylight? July 24th (14 hours, 58 minutes, and 22 seconds)
*When Is The Sunrise At/After 6 AM?: August 2nd (6:00 AM)
*When Is The Sunset At/Before 8:30 PM?: August 7th (8:30 PM)

_______________________________________________

This Day in Weather History
July 21st

2002: Dew points reach 84 degrees at Madison, Morris, and Olivia. This ties the all time highest dew point reading in Minnesota, as recorded by the State Climatology Office.

1934: Extreme heat hits western Minnesota, and the temperature topped out at 113 at Milan.

_______________________________________________

National Weather Forecast

On Wednesday, a frontal boundary snaking from the Northeast to the Northern Plains will help produce at least scattered showers and thunderstorms. Another frontal boundary across the Southeast and Gulf Coast with an area of low pressure attached will produce storms there as well. Monsoonal storms will be possible in the Four Corners region.

The heaviest rain the next few days will be along the Gulf Coast and in the Southeast, where some 1-3" tallies will be possible.

_______________________________________________

Extreme heat bakes Northwest and northern Rockies amid high fire danger

More from the Washington Post: "For the fourth time in the past month and a half, a strong heat wave is roasting parts of the western U.S., as wildfires run amok. High-temperature records could fall in parts of the northern Rockies on Monday, where the most exceptional lobe of warmth is concentrated. There are signs that the seemingly unrelenting heat that has proved a staple of summer 2021 won't be going anywhere anytime soon, with prolonged hot, dry conditions likely for weeks over large areas of the western Lower 48. The heat is contributing to increased wildfire danger as dozens of blazes rage across 12 states in the West, including in south-central Oregon, where the Bootleg Fire already has charred more than 300,000 aces. Six additional wildfires have already swollen to 50,000 acres in size or larger — and roughly two months remain until the peak of wildfire season."

Today's Wildfires Are Taking Us into Uncharted Territory

More from Scientific American: "When smoke from blazing forests in the West tinted skies ochre across much of the U.S. last year, we asked, "How much worse can fire seasons get?" Fire paleoecologist Philip Higuera has spent his career trying to determine the answer by looking at history. "If we're all wondering what happens when our forests warm up," he says, "let's see what happened in the past when they warmed up." The central Rocky Mountains' subalpine forests grow in cool, wet conditions and burn less readily than their lowland counterparts. To find how frequently these tough woodlands still caught fire through the ages, Higuera and his colleagues combined records from modern satellite-observed fires, fire scars in tree rings from the 1600s onward and flecks of charcoal that settled in lakes over thousands of years. The study found that from 2010 to 2020, the forests burned 22 percent faster than they did during an unusual warming period that started in A.D. 770 and saw the area's highest temperatures before the 21st century. Most of this burn rate increase was caused by the 2020 fire season alone. And 72 percent of the total area burned between 1986 and 2020 resulted from fires in just the latter year."

uOttawa study first to investigate newly introduced butterfly, which could become widespread in Canada

More from the University of Ottawa: "This summer, if you see a butterfly with wings that are blue on top with orange spots underneath, you may have crossed paths with a male European Common Blue (or Polyommatus icarus), a newly introduced species in Canada. Could it be a fluke? Probably not, according to a group of researchers from the University of Ottawa who have taken a close look at this captivating blue creature. They are in fact the first to study its ecology. "The results of our study suggest that the Polyommatus icarus (P. icarus) could become widespread in the future since it prefers urban areas," said uOttawa PhD student Stephanie Rivest, who is the first author of the article "Anthropogenic disturbance promotes the abundance of a newly introduced butterfly, the European common blue (Polyommatus icarus; Lepidoptera: Lycaenidae), in Canada" published in the Canadian Journal of Zoology."

_______________________________________________

Thanks for checking in and have a great day! Don't forget to follow me on Twitter (@dkayserwx) and like me on Facebook (Meteorologist D.J. Kayser).

- D.J. Kayser