Updraft® - Minnesota Weather News

Rain chances increase on Friday; Coolest State Fair

The start of our Minnesota State Fair is here!

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Minnesota State Fair

If you like cool weather, you'll like the next several days, with highs mostly in the 70s at the Fair.

It's been cooler than this at State Fair time.

According to the Minnesota State Climatology Office :

The coolest Minnesota State Fair was during the six-day run of the Fair from September 5-10 1898 with an average maximum temperature of 64.2 degrees. The coldest maximum temperature for the Fair is 52 degrees on September 7, 1911, and the coldest minimum temperature is 33 degrees on September 13, 1890. The coolest Fair morning in recent years was a chilly 36 degrees on September 1, 1974.

Temperature trends

Northeastern and north-central Minnesota will see highs in the 60s this Thursday through Sunday, with mostly lower 70s elsewhere.

Here's a detailed look at Saturday's highs:

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Sunday looks like this:

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Our next shot at hitting 80 degrees in the Twin Cities metro area will be next Tuesday.

 Rain chances

Some very scattered showers are possible in southern Minnesota Thursday afternoon, but most spots will stay dry.

There is a chance of occasional scattered showers and thunderstorms across much of Minnesota on Friday.

The National Oceanic and Atmospheric Administration's North American Mesoscale forecast model shows the potential rain pattern:

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NOAA NAM simulated radar Friday and Friday evening, via tropicaltidbits

There will be a higher chance of some showers and thunderstorms on Saturday, then a chance of a shower or thunderstorm on Sunday.

Drought update

The latest update from U.S. Drought Monitor shows that the worst drought conditions are over eastern Montana and much of North and South Dakota:

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

Parts of northwestern Minnesota and north-central Minnesota remain in moderate drought:

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

The areas that are shaded yellow are abnormally dry, but not in drought.

Tropical Storm Harvey

Tropical Storm Harvey is spinning over the Gulf of Mexico, with max sustained winds of 60 mph Thursday morning:

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NOAA visible satellite loop, via College of DuPage

Harvey is expected to strengthen as it moves toward the Texas coast over the next 24-36 hours, and could become a hurricane on Friday.

Tropical Storms become hurricanes when their sustained winds reach 74 mph or greater.

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

BULLETIN

Tropical Storm Harvey Intermediate Advisory Number 15A

NWS National Hurricane Center Miami FL AL092017

700 AM CDT Thu Aug 24 2017

...AIR FORCE HURRICANE HUNTER PLANE FINDS HARVEY STRENGTHENING...

 

SUMMARY OF 700 AM CDT...1200 UTC...INFORMATION

----------------------------------------------

LOCATION...23.8N 93.0W

ABOUT 380 MI...615 KM SE OF PORT OCONNOR TEXAS

ABOUT 335 MI...540 KM SE OF PORT MANSFIELD TEXAS

MAXIMUM SUSTAINED WINDS...60 MPH...95 KM/H

PRESENT MOVEMENT...NNW OR 345 DEGREES AT 10 MPH...17 KM/H

MINIMUM CENTRAL PRESSURE...986 MB...29.12 INCHES

 

WATCHES AND WARNINGS

--------------------

CHANGES WITH THIS ADVISORY:

None.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Storm Surge Warning is in effect for...

* Port Mansfield to San Luis Pass Texas

A Storm Surge Watch is in effect for...

* South of Port Mansfield Texas to the Mouth of the Rio Grande

* North of San Luis Pass to High Island Texas

A Hurricane Warning is in effect for...

* Port Mansfield to Matagorda Texas

A Tropical Storm Warning is in effect for...

* North of Matagorda to High Island Texas

* South of Port Mansfield Texas to the Mouth of the Rio Grande

A Hurricane Watch is in effect for...

* South of Port Mansfield Texas to the Mouth of the Rio Grande

A Tropical Storm Watch is effect for...

* South of the Mouth of the Rio Grande to Boca de Catan Mexico

A Storm Surge Warning means there is a danger of life-threatening

inundation, from rising water moving inland from the coastline,

during the next 36 hours in the indicated locations. For a

depiction of areas at risk, please see the National Weather

Service Storm Surge Watch/Warning Graphic, available at

hurricanes.gov. This is a life-threatening situation. Persons

located within these areas should take all necessary actions to

protect life and property from rising water and the potential for

other dangerous conditions. Promptly follow evacuation and other

instructions from local officials.

A Hurricane Warning means that hurricane conditions are expected

somewhere within the warning area. A warning is typically issued

36 hours before the anticipated first occurrence of tropical-storm-

force winds, conditions that make outside preparations difficult or

dangerous. Preparations to protect life and property should be

rushed to completion.

A Tropical Storm Warning means that tropical storm conditions are

expected somewhere within the warning area within 36 hours.

A Storm Surge Watch means there is a possibility of life-

threatening inundation, from rising water moving inland from the

coastline, in the indicated locations during the next 48 hours.

A Hurricane Watch means that hurricane conditions are possible

within the watch area.

A Tropical Storm Watch means that tropical storm conditions are

possible within the watch area.

In addition, interests in southwestern Louisiana should continue to

monitor the progress of this system.

For storm information specific to your area in the United

States, including possible inland watches and warnings, please

monitor products issued by your local National Weather Service

forecast office. For storm information specific to your area outside

the United States, please monitor products issued by your national

meteorological service.

 

DISCUSSION AND 48-HOUR OUTLOOK

------------------------------

At 700 AM CDT (1200 UTC), the center of Tropical Storm Harvey was

located by a reconnaissance plane near latitude 23.8 North,

longitude 93.0 West. Harvey is moving toward the north-northwest

near 10 mph (17 km/h). A track toward the northwest or

north-northwest at a faster forward speed is expected for the next

48 hours. On the forecast track, Harvey will approach the southern

Texas coast on Friday.

An Air Force Reserve aircraft reports that the maximum sustained

winds have increased to near 60 mph (95 km/h) with higher gusts.

Additional strengthening is forecast during the next 48 hours, and

Harvey is expected to become a hurricane by Friday.

Tropical-storm-force winds extend outward up to 115 miles (185 km)

from the center.

The minimum central pressure based on data from the Air Force

Hurricane Hunter aircraft is 986 mb (29.12 inches).

 

HAZARDS AFFECTING LAND

----------------------

RAINFALL: Harvey is expected to produce total rain accumulations of

10 to 15 inches with isolated maximum amounts of 25 inches over the

Texas coast through next Wednesday. During the same time period

Harvey is expected to produce total rain accumulations of 3 to 9

inches along its outer radius including parts of south, central, and

eastern Texas and the lower Mississippi Valley. Rainfall from Harvey

may cause life-threatening flooding.

STORM SURGE: The combination of a dangerous storm surge and the

tide will cause normally dry areas near the coast to be flooded by

rising waters moving inland from the shoreline. The water is

expected to reach the following heights above ground if the peak

surge occurs at the time of high tide...

Port Mansfield to San Luis Pass...5 to 7 ft

San Luis Pass to High Island...2 to 4 ft

Mouth of the Rio Grande to Port Mansfield...2 to 4 ft

The deepest water will occur along the immediate coast near and to

the northeast of the landfall location, where the surge will be

accompanied by large and destructive waves. Surge-related flooding

depends on the relative timing of the surge and the tidal cycle, and

can vary greatly over short distances. For information specific to

your area, please see products issued by your local National Weather

Service forecast office.

WIND: Hurricane conditions are likely within the hurricane warning

area late Friday or Friday night, with tropical storm conditions

expected to first reach the coast in the hurricane warning area

Friday.

SURF: Swells generated by Harvey are likely to affect the Texas,

Louisiana, and northeast Mexico coasts by Friday. These swells are

likely to cause life-threatening surf and rip current conditions.

Please consult products from your local weather office.

Here's Harvey's projected path:

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National Hurricane Center

Harvey could dump 15 inches or more of rain in parts of south Texas:

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National Hurricane Center

The National Hurricane Center will update their Harvey forecast every few hours.

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.