Updraft® - Minnesota Weather News

Smoky sunrise; pleasant weekend

Minnesota Pollution Control Agency

The eastern sky had a red-orange display at sunrise Friday morning.

The colorful sunrise was caused by smoke from wildfires in Canada and the western United States.

A shift in wind patterns is expected to reduce the smoke over Minnesota this weekend.

Minnesota air quality

As of 9 a.m. Friday, the Minnesota Pollution Control Agency showed moderate air quality over much of Minnesota, including the Twin Cities metro area.

Parts of southwestern Minnesota were in either the "unhealthy" or "unhealthy for sensitive groups" category:

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Minnesota Polution Control Agency

Air quality readings will change at times, so you might want to check back for MPCA air quality updates.

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Update for air quality alert from MPCA

The Minnesota Pollution Control Agency has issued an air quality alert that is in effect from today until 6. a.m. Saturday for parts of southwestern, west-central and central Minnesota:

The Minnesota Pollution Control Agency (MPCA) is issuing an air quality alert for southwest, western and central Minnesota, effective Friday, Sept. 1 beginning at 9 a.m. through 6 a.m. Saturday, Sept. 2.

The affected area includes residents of Alexandria, Brainerd, Marshall, Ortonville, St. Cloud and Worthington. Also impacted are the Tribal Nations of Mille Lacs and Upper Sioux.

Canadian wildfire smoke continues across much of southern, western and central Minnesota. Air pollution monitors are showing an increase in fine particles as thicker smoke moves north from northwest Iowa into the southwestern portion of Minnesota.

Smoke will continue to persist and move northward as southerly winds develop across western Minnesota.

During this time, fine particle pollution is expected to remain at, or above, a level that is considered unhealthy for sensitive groups. Showers and thunderstorms will approach western and northwestern Minnesota this evening helping to disperse smoke in some areas.

Southwest and central Minnesota will continue with higher fine particle levels through the overnight hours until precipitation arrives. By Saturday morning, most areas of smoke will be pushed south and dissipated.

People whose health is affected by unhealthy air quality:  There are people who are more likely to be affected when fine particle pollution reaches an unhealthy level.

  • People who have asthma or other breathing conditions like chronic obstructive pulmonary disease (COPD).

  • People who have heart disease or high blood pressure.

  • Children and older adults.

  • People of all ages who are doing extended or heavy, physical activity like playing sports or working outdoors.

Health effects: Air pollution can aggravate heart and cardiovascular disease as well as lung diseases like asthma and COPD. When the air quality is unhealthy, people with these conditions may experience symptoms like chest pain, shortness of breath, wheezing, coughing or fatigue. If you are experiencing any of these symptoms, use your inhalers as directed and contact your health care provider.

Here's a map of counties that are included in the MPCA air quality alert, courtesy of the National Weather Service:

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NWS Twin Cities

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Drought update

The latest update from U.S. Drought Monitor indicates that the worst drought conditions in the U.S. are in Montana and western sections of North and South Dakota:

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U.S. Drought Monitor/USDA/NOAA/University of Nebraska-Lincoln

Parts of northwestern Minnesota remain in moderate drought:

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U.S. Drought Monitor/USDA/NOAA/University of Nebraska-Lincoln

The yellow shaded areas are abnormally dry but not in drought, according to the U.S. Drought Monitor.

Rain chances

We could see scattered showers and an isolated thunderstorm in western Minnesota later Friday afternoon into Friday evening.

Eastern Minnesota and the Twin Cities metro area could see scattered showers/an isolated thunderstorm Friday night into Saturday morning.

The National Oceanic and Atmospheric Administration's North American Mesoscale forecast model shows the potential rain pattern from Friday afternoon through Saturday morning:

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NOAA NAM simulated radar from noon Friday to noon Saturday, via tropicaltidbits

It could rain in some spots that look dry on the simulated radar loop, but the loop shows the general rain pattern that's expected.

The color chart to the right of the loop refers to the strength of the signal that returns to the radar, not to the amount of rain.

Sunday and Labor Day look mostly dry over Minnesota.

Temperature trends

Many spots will reach the lower 70s Friday afternoon, but most of northeastern Minnesota will see highs in the 60s.

Saturday highs will also be mostly in the 70s:

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A few spots in the southwest could touch 80.

On Sunday, much of Minnesota will see 80s, with 70s northeast:

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I wouldn't be surprised to see some spots in the Twin Cities reach the mid 80s on Sunday.

Labor Day will feature 70s central and south, with 60s north:

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By Sept. 4 (Labor Day), our average high in the Twin Cities metro area drops to 76 degrees.

Hurricane Irma

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NOAA Hurricane Irma infrared loop

Hurricane Irma has strengthened to a Category 3 hurricane over the eastern Atlantic Ocean, and has maximum sustained winds of 115 mph.

Here's the latest on Hurricane Irma, from the National Hurricane Center:

BULLETIN

Hurricane Irma Advisory Number 8

NWS National Hurricane Center Miami FL AL112017

500 AM AST Fri Sep 01 2017

...IRMA HOLDING STEADY WITH 115-MPH WINDS...

 

SUMMARY OF 500 AM AST...0900 UTC...INFORMATION

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LOCATION...18.2N 36.5W

ABOUT 840 MI...1350 KM WNW OF THE CABO VERDE ISLANDS

ABOUT 1665 MI...2680 KM E OF THE LEEWARD ISLANDS

MAXIMUM SUSTAINED WINDS...115 MPH...185 KM/H

PRESENT MOVEMENT...WNW OR 300 DEGREES AT 12 MPH...19 KM/H

MINIMUM CENTRAL PRESSURE...967 MB...28.56 INCHES

 

WATCHES AND WARNINGS

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There are no coastal watches or warnings in effect.

 

DISCUSSION AND 48-HOUR OUTLOOK

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At 500 AM AST (0900 UTC), the center of Hurricane Irma was located

near latitude 18.2 North, longitude 36.5 West. Irma is moving

toward the west-northwest near 12 mph (19 km/h). A turn toward the

west is expected by tonight, followed by a turn toward the

west-southwest on Saturday.

Maximum sustained winds remain near 115 mph (185 km/h) with higher

gusts. Irma is a category 3 hurricane on the Saffir-Simpson

Hurricane Wind Scale. Fluctuations in strength, up or down, are

possible during the next few days, but Irma is expected to

remain a powerful hurricane through the weekend.

Hurricane-force winds extend outward up to 15 miles (30 km) from the

center, and tropical-storm-force winds extend outward up to 90 miles

(150 km).

The estimated minimum central pressure is 967 mb (28.56 inches).

 

HAZARDS AFFECTING LAND

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None

 

NEXT ADVISORY

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Next complete advisory at 1100 AM AST.

Hurricane Irma is expected to move westward this weekend:

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National Hurricane Center

Irma could be close to the Lesser Antilles of the Caribbean by next Wednesday.

Some forecast models show Irma heading toward Florida or the Gulf of Mexico later next week, while others show a track that veers away from the east coast of the U.S.:

Irma will be watched closely.

Programming note

You can hear my live weather updates on Minnesota Public Radio at 7:49 a.m. Thursdays and Fridays, and at 7:35 a.m., 9:35 a.m. and 4:35 p.m. each Saturday and Sunday.