Scattered showers/t-storms tonight, a few storms could be strong to severe, heavy rain and some flooding possible in parts of the Northland) Nicer weather returns Saturday; Scattered t-storms possible Sunday

/Issued 4:58 PM CDT, Friday, August 31, 2018/


Large scale forcing appears to be increasing in the Northland late this afternoon but there are still some negatives in place for thunderstorm development, so will just have to wait and see how things shake out during the next few hours, if thunderstorms do develop, they could become severe with favorable amounts of instability and wind shear over the area.

Note:  Yellow outlined area on map is where I’m watching for the potential of strong to severe thunderstorms this evening.

…Flash Flood Watch remains in effect from this evening through early Saturday morning for parts of northeast Minnesota and all of northwest Wisconsin, including the Twin Ports, North Shore and South Shore…

September Climate Normals for Duluth, Minnesota

Temperature:  55.6 degrees
Precipitation:  4.1″
Snowfall:  0.1″

Warmest September on record:  62.6 degrees set in 1897
Coldest September on record:  47.8 degrees set in 1974

Normal high on the 1st:  71 degrees
Normal high on the 30th:  59 degrees

Normal low on the 1st:  52 degrees
Normal low on the 30th:  40 degrees

Wettest September on record:  11.52″ set in 1881
Driest September on record:  0.19″ set in 1952

Snowiest September on record:  2.4″ set in 1991

Average number of days with a high temp of at least 80 F:  2; Record is 10 days set in September 1908.

Average number of days with a low temp of 32 F or lower:  1; Record is 7 days set in 1974.

Astronomical Data

Sunrise on September 1:  6:28 AM CDT
Sunrise on September 30:  7:05 AM CDT

Sunset on September 1:  7:48 PM CDT
Sunset on September 30:  6:49 PM CDT

Note:  The first official day of fall is September 22, but Meteorological fall begins on September 1, or the 3-month period from September 1 to November 30.

Meteorological fall Climate Normals for Duluth, Minnesota
Period:  Sep 1 to Nov 30

Temperature:  42.5 degrees
Precipitation:  9.05″
Snowfall:  16.1″

Normal High on September 1:  71 degrees
Normal High on November 30:  28 degrees

Normal Low on September 1:  52 degrees
Normal Low on November 30:  14 degrees

Sunrise on September 1:  6:28 AM CDT
Sunrise on November 30:  7:31 AM CST

Sunset on September 1:  7:48 PM CDT
Sunset on November 30:  4:22 PM CST

Note:  Daylight Saving Time ends on November 4 at 2 AM.  We fall back an hour on the 4th.

Meteorological fall 2017 climate stats for Duluth, Minnesota

Average temperature:  43.3 degrees
Departure:  +0.8 degrees above normal

Precipitation:  8.26″
Departure:  -0.79″ below normal

Snowfall:  21.6″
Departure:  +5.5″ above normal

Local Storm Reports for August 31, 2018

•3:40 PM CDT:  Hail — 0.25 inch.  1 NW Loman, MN (Koochiching County)

•3:56 AM CDT:  Hail — 1.00 inch.  2 NE Mercer, WI (Iron County)  Quarter sized hail.

Weather Synopsis

A mild, muggy but rather gloomy day as we end the month of August.  The Northland saw plenty of clouds today with warm southerly winds, highs were mainly in the 70s with dew points in the mid to upper 60s!  An area of thunderstorms affected a small part of far northern Minnesota this afternoon, otherwise it’s been mainly dry with just a few areas of drizzle or showers.

Late afternoon RAP model analysis showed SW flow aloft covering the upper Midwest with an elevated mixed layer resulting in very steep mid level rates from 8.0 to 9.0 c/km! The air is capped, however, over most of the Northland late this afternoon with CIN to 100 J/kg except in western/far northern portions of the area where the cap is much weaker.


Still have some doubts on how things will play out tonight, but with a cold front and trough approaching from the west combined with the already unstable airmass over the area, the potential remains for scattered strong to severe thunderstorms over northeast Minnesota and northwest Wisconsin — Large scale forcing tied with the cold front and trough will need to be strong enough to erode the cap, if that doesn’t happen, then we probably won’t see much in the way of thunderstorm activity tonight.


Cold front exits to the east by daybreak as high pressure builds into the upper Midwest for Saturday.  Mostly cloudy skies during the morning should give way to some sunshine by the afternoon with highs in the 70s.


Another cold front moves through the Northland during the afternoon-evening time frame.  If we can build up enough instability and keep enough moisture around, then isolated to scattered showers and thunderstorms will be possible Sunday into Sunday evening.  Highs Sunday will be in the 70s.

Duluth, Minnesota Climate Normals for September 1

High:  71
Low:   52

Sunrise Saturday:  6:28 AM CDT
Sunset Saturday:   7:48 PM CDT


Flash Flood Watch in effect for parts of the Northland this evening/overnight; Potential for strong to severe t-storms this afternoon-evening. Stay Weather Aware!

/Issued 7:22 AM CDT, Friday, August 31, 2018/

…Flash Flood Watch in effect for parts of northeast Minnesota and northwest Wisconsin from this evening into Saturday morning, this flash flood watch does include the cities of Duluth and Superior.

Note:  A flash flood watch means that flash flooding is possible in or close to the watch area.


09z RAP model


12z HRRR model

Radar forecast valid from 1 PM today to 4 AM Saturday.

This model shows scattered thunderstorms developing by mid or late afternoon over north central/western areas of Minnesota, storms would then move generally toward the east this evening.

Weather Synopsis

Scattered showers and thunderstorms have been occurring early this morning mainly in northwest Wisconsin into far eastern Minnesota, heavy downpours and some lightning have been the main threats from these storms.  A warm advection pattern has been the main driving force behind this early morning convection.

We’re looking at a muggy final day of August across the Northland with dew points today in the 60s, possibly up around 70 degrees this afternoon in southern portions of the area. 

Surface map at 8 AM had a cold front draped from far northwest Minnesota to central South Dakota with a SW mid/upper level flow covering the northern Plains and upper Midwest as energy digs E/SE out of the northern Rockies.

An area of higher instability is already in place across the upper Midwest this morning, and this area of instability will remain over the area through this evening with CAPE from 1000 to around 3000 J/kg along with very steep mid level lapse rates from 7.0 to around 8.5 c/km.  Mid and upper level winds and the amount of wind shear combined with the strong instability and the approach of a cold front and any possible disturbance moving into our area will provide the necessary lift for thunderstorm development with a few strong to severe thunderstorms possible from mid or late afternoon and through the evening hours.

Damaging winds and large hail will be the main threats if severe storms develop later today.

Heavy rain is also possible with PWATS in the 1.50 to 1.90 inch range late this afternoon/evening.  If storms start to move over the same location for a few hours, that would increase the potential for flash flooding.

Otherwise for today we can expect mostly cloudy skies, although some breaks in the clouds are certainly possible at times, highs will range from the upper 60s to upper 70s.

Note:  Saturday is looking like a nicer day around here with some sun especially by the afternoon, highs are forecast to be in the 70s, not bad at all for the first day of September!


Northland weather: Fair and cool tonight; Southerly breezes, highs in the 70s for Thursday; Shower/t-storm chances increase Thursday night-Friday

/Issued 5:53 PM CDT, Wednesday, August 29, 2018/



12z European model 8-29-2018


18z 3km NAM

Radar Forecast valid from 7 PM Thursday to 7 AM Friday — Scattered showers and thunderstorms develop over west central Minnesota Thursday evening, then spread E-NE late Thursday night-early Friday morning.  Heavy downpours and lightning will occur with these storms with hail possible in the strongest storms.

Note:  I think will stay dry in Duluth Thursday evening followed by increasing chances for showers and thunderstorms early Friday morning the way it looks now.


12z GEFS model 8-29-2018

Precipitation Anomaly Forecast valid through September 14, 2018 — Little change in the overall weather pattern through possibly mid September.  More frequent rainfalls expected in northeast Minnesota and northwest Wisconsin resulting in above average rainfall totals over the next 2 weeks or so.

Note:  Green colors on map represent above average rainfall totals.

…Climate Data for August 29, 2018…

International Falls, Minnesota

4th coldest low temperature on record for August 29 with a low Wednesday morning of 37 degrees.  The record low for August 29 is 33 degrees set in 1911 and tied in 1917.

…Climate Data for August 28, 2018…

Hibbing, Minnesota

Record cold high temperature set for August 28 with a high on Tuesday of 55 degrees, this breaks the previous record cold high of 58 degrees which was set on August 28, 1946.

International Falls, Minnesota

Tied for coldest high temperature on record for August 28 with a high on Tuesday of 58 degrees, this ties with August 28, 1976 and August 28, 1988 for coldest high temperature on record for August 28.

Ashland, Wisconsin

Tied for 3rd coldest high temperature on record for August 28 with a high on Tuesday of 62 degrees.  Record cold high for August 28 is 60 degrees set in 1946.

Brainerd, Minnesota

Tied for 5th coldest high temperature on record for August 28 with a high on Tuesday of 62 degrees.  Record cold high for August 28 is 57 degrees set in 1935.

Duluth, Minnesota

Tied for 5th coldest high temperature on record for August 28 with a high on Tuesday of 59 degrees.  Record cold high for August 28 is 54 degrees set in 1885 and tied in 1931.

Weather Tidbits for Duluth, Minnesota

•High temperature of 59 degrees on Tuesday, August 28 was the coldest high temperature since June 24, high of 58 degrees.

•Summer of 2018 should go into the books as a warmer than average summer. 
The average temperature from June 1 to August 28 was 66.3 degrees (+2.8 degrees above normal) There are only 3 days left of Meteorological summer (the period from June 1 to August 31) and its unlikely that our average temperature would drop below average with just a few days left to go before the end of meteorological summer.

•As for rainfall — 11.08 inches of rain has fallen so far this summer (thru Aug 29) which is -0.45 inches below normal.  Rainfall for the summer could tilt above average depending on how much rain we get Thursday night/Friday.

Weather Synopsis

A much more pleasant day compared to Tuesday’s weather around here.  We saw a mix of sun and clouds across the Northland today with highs in the mid 60s to around 70 degrees, about 5 degrees cooler than normal for late August.

Surface map late this afternoon had an area of high pressure over southwest Minnesota/northern Iowa. 

Upper level analysis per RAP model showed W-NW flow covering the upper Midwest this afternoon while the next dip in the jet stream heads into the Pacific northwest, and this will be the next system that will affect the upper Midwest by Friday. 

A plume of steep mid level lapse rates over 9.0 c/km associated with the elevated mixed layer covered the Rockies and western High Plains this afternoon, and as the energy now over the northwest U.S. moves farther east it will help turn mid/upper level winds more to the southwest which will advect higher lapse rates and instability into the upper Midwest Thursday night into Friday.


Clear to partly cloudy skies with pleasantly cool conditions, lows will be in the 40s to lower 50s, but a few of the typical cold spots could drop into the 30s once again.


Southerly winds increase to 10 to 25 mph with mostly sunny to partly cloudy skies expected during the day, highs will mainly be in the 70s except cooler along the North Shore of Lake Superior.  Elevated instability, steeper mid level lapse rates and moisture advecting NE into our area Thursday night will probably lead to the development of a few to scattered coverage showers and thunderstorms later Thursday night or early Friday morning.


Scattered showers and thunderstorms are possible as a low pressure system with its warm front and cold front move into the upper Midwest.  There is some uncertainty on how things setup Friday, but the potential is there for a rather unstable airmass to develop over some parts of the Northland, this combined with stronger winds aloft and favorable wind shear could cause a few strong to severe thunderstorms in parts of the Northland Friday afternoon or Friday evening.

…Looking ahead…

Saturday, mainly dry with highs in the 70s the way it looks now.  Sunday and Labor Day could see a few showers and thunderstorms returning to the Northland, but it doesn’t look like either day would be a complete washout.

Duluth, Minnesota Climate Normals for August 30

High:  71
Low:   52

Sunrise Thursday:  6:26 AM CDT
Sunset Thursday:   7:52 PM CDT


Cool tonight (30s in northern Minn) Clouds, patchy drizzle, some clearing late. Little nicer Wed with some sun

/Issued 6:09 PM CDT, Tuesday, August 28, 2018/


Source for rainfall totals




Goes-16 one minute meso-scale Infrared Satellite loop from Tuesday, August 28, 2018

Loop time: 4:15 PM to 5:32 PM.

Stunning satellite loop showing the powerful clusters of torrential downpours and strong to severe thunderstorms this afternoon from Iowa to Wisconsin to Michigan.


Widespread heavy rain and strong to severe thunderstorms continue to affect parts of southeast Minnesota, and southern, central and eastern Wisconsin this afternoon, radar loop through 4:35 PM Tuesday, August 28, 2018.


Weather Prediction Center doesn’t issued high risks for flash flooding very often, but they have issued one for the rest of today into tonight for parts of southern Wisconsin — Potentially dangerous and life threatening flooding through tonight!


Temperatures were running 10 to around 20 degrees colder this afternoon compared to Monday afternoon in northeast Minnesota and northwest Wisconsin.



Temperature Departure map for the Midwest for the week of August 19, 2018.


Precipitation Departure map for the Midwest for the week of August 19, 2018.

Temperature and Precipitation report for Duluth, Minnesota

August 19 through 25, 2018

High Temperatures/Departure from Normal

8/19:  81 F/+7 degrees above normal
8/20:  71 F/-3 degrees below normal
8/21:  74 F/Normal
8/22:  80 F/+7 degrees above normal
8/23:  79 F/+6 degrees above normal
8/24:  68 F/-5 degrees below normal
8/25:  75 F/+2 degrees above normal

Low Temperatures/Departure from Normal

8/19:  60 F/+6 degrees above normal
8/20:  61 F/+7 degrees above normal
8/21:  55 F/+1 degree above normal
8/22:  50 F/-4 degrees below normal
8/23:  54 F/Normal
8/24:  63 F/+10 degrees above normal
8/25:  60 F/+7 degrees above normal

Note:  Average Temperature for the week of August 19:  66.5 degrees (+2.9 degrees above normal)  Source:

Total Precipitation:  0.53 inches
Normal:  0.86″
Departure:  -0.33 inches below normal

State Average for Minnesota for the week of August 19, 2018

Temperature:  66.5 degrees
Departure:  -0.5 degrees below normal

Precipitation:  1.09 inches
Departure:  +0.29 inches above normal

Weather Synopsis

A true taste of fall weather across the Northland today with widespread clouds, mist/drizzle and patchy fog.  Highs today were mainly in the 50s, although Brainerd and Hayward had to be show-offs with both locations in the lower 60s late this afternoon. 

A strong baroclinic zone (Temperature gradient) was in place this afternoon with 850mb temps ranging from +4C in northern Minnesota to +20C in far southern Wisconsin — Cold front separating the cool to warm air stretched from eastern Ontario Province to southern Wisconsin to central Kansas.


Mostly cloudy skies with patchy drizzle lingering in the Northland with some clearing expected during the night.  Lows will be in the 40s, slightly warmer near Lake Superior while some locations in northern Minnesota dip into the 30s if skies clear out soon enough, and there could even be a little patchy frost in a few spots up north Wednesday morning if skies clear early enough.


Looks like will have somewhat nicer weather for Wednesday compared to Tuesday’s weather.  Partly to mostly sunny skies are expected with highs in the 60s to around 70 degrees.


Our next system will begin to affect us starting Thursday as southerly winds develop ahead of low pressure to our west.  A warm/moist advection pattern will begin, and this combined with an increase in elevated instability will probably be enough to kick off a few showers and thunderstorms in parts of the Northland especially Thursday night the way it looks now.  Highs Thursday will mainly be in the 70s, cooler along the North Shore of Lake Superior.

…Looking ahead to Friday…

A complex weather system consisting of a warm front, cold front and trough will be moving through the upper Midwest.  Looks like will get some rain and thunderstorms in the Northland, but how much rain is uncertain as the computer models disagree a bit with the 12z Euro much wetter while the 12z and 18z NAM keeps the heavier rainfall much farther to the south with only scattered showers in the Northland.

Duluth, Minnesota Climate Normals for August 29

High:  72
Low:   52

Sunrise Wednesday:  6:25 AM CDT
Sunset Wednesday:   7:54 PM CDT


Reports of 2-5" of rain and wind damage from Monday afternoon storms which hit parts of the Northland. Flash Flooding occurring in Hayward, WI and Sandstone, MN this evening. Fall feel Tuesday, patchy frost Wed AM in parts of northern Minn. Warmer and stormier weather could return late week

/Issued 7:47 PM CDT, Monday, August 27, 2018/

Flash Flood Warning statement from the National Weather Service in Duluth, Minnesota


Radar loop ending at 8:10 PM CDT, Monday, August 27, 2018 — Rain and thunderstorms continue to move northeast through northeast Minnesota and northwest Wisconsin, but the rain is ending from SW-NE, and should move out of our area by around 10 PM.


Here’s the Goes-16 Infrared satellite loop from Monday, August 27, 2018 — This shows the temperature of the clouds with orange and red colors representing cloud top temps of -60 to -70C! Wow!

Loop time:  1:07 PM to 7:22 PM.



RTMA model


18z NAM model

Local Storm Reports for August 27, 2018

7:30 PM:  Heavy Rain — 3.00 inch.  Hawthorne, WI (Douglas County)

7:30 PM:  Flash Flood — Hayward, WI (Sawyer County)  Water covering Highway 63 in Hayward and Railroad street.

7:05 PM:  Thunderstorm Wind Damage — Poplar, WI (Douglas County)  Trees knocked down.

7:03 PM:  Thunderstorm Wind Damage — 7 NNW Spooner, WI (Washburn County)  6 inch diameter tree downed partially blocking Big Bass Lake road.

7:00 PM:  Heavy Rain — 1.12 inch.  1 W Washburn, WI (Bayfield County)

6:15 PM:  Heavy Rain — 5.60 inch.  2 SW Hinckley, MN (Pine County)  Rainfall of 3.3 inch from 2:50 PM to 3:20 PM.  Rainfall of 2.3 inch from 5:30 PM to 6:10 PM.

6:00 PM:  Heavy Rain — 3.50 inch.  4 W Hinckley, MN (Pine County)  The duration of the heavy rain event was 30 minutes.

5:55 PM:  Thunderstorm Wind Damage — 1 WNW Hurley, WI (Iron County)  A few trees knocked down into business parking lots along 10th avenue north.

5:50 PM:  Flash Flood — Sandstone, MN (Pine County)  Water covering a few roadways.

5:50 PM:  Thunderstorm Wind Damage — Montreal, WI (Iron County)  Several trees knocked down along Highway 77 in Montreal.

5:45 PM:  Thunderstorm Wind Damage — Sandstone, MN (Pine County)  Tree knocked down.

5:15 PM:  Heavy Rain — 2.30 inch.  Maple, WI (Douglas County)

5:00 PM:  Heavy Rain — 2.78 inch.  5 NNE Brule, WI (Bayfield County)  Total rainfall accumulation over the past hour.

4:43 PM:  Thunderstorm Wind Damage — Drummond, WI (Bayfield County)  A few trees downed.

4:42 PM:  Thunderstorm Wind Damage — 4 NNW Iron River, WI (Bayfield County)  Few trees knocked down in Oulu.

4:38 PM:  Thunderstorm Wind Damage — 4 SSE Iron River, WI (Bayfield County)  6 inch diameter live tree limb knocked down from winds.

4:25 PM:  Thunderstorm Wind Damage — 12 W Drummond, WI (Bayfield County)  A few trees knocked down in Barnes, WI.

4:20 PM:  Thunderstorm Wind Damage — 4 ENE Webb Lake, WI (Washburn County)  Power lines knocked down on State Highway 77 along the border of Washburn and Burnett Counties.

4:04 PM:  Thunderstorm Wind Damage — Solon Springs, WI (Douglas County)  Tree knocked down along County road A in Solon Springs.

3:30 PM:  Heavy Rain — 3.30 inch.  4 E Cloverdale, MN (Pine County)

3:20 PM:  Heavy Rain — 3.30 inch.  2 SW Hinckley, MN (Pine County)  Rainfall fell in a span of 30 minutes.

3:15 AM:  Hail — 0.25 inch.  3 NW Gheen, MN (St. Louis County)

1:35 AM:  Thunderstorm Wind Damage — 1 WSW International Falls, MN (Koochiching County)  Multiple large trees uprooted.

1:35 AM:  Thunderstorm Wind Gust — 55 mph.  International Falls, MN (Koochiching County)

Rainfall Reports for August 26-27, 2018

Note:  Totals listed below are from 7 AM Sunday to 7 AM Monday.

Gordon, WI:  2.45 in
Ashland, WI:  1.62 in
Bruno, MN:  1.59 in
3 E Orr, MN:  1.09 in
Morgan Park, MN:  1.00 in
Kabetogama, MN:  0.75 in
Northome, MN:  0.69 in
25 E Ely, MN:  0.62 in
International Falls, MN:  0.58 in
8 S Bigfork, MN:  0.47 in
Floodwood, MN:  0.40 in
Grand Portage, MN:  0.36 in
Babbitt, MN:  0.35 in
Duluth Airport:  0.34 in
Embarrass, MN:  0.33 in
12 N Grand Rapids, MN:  0.30 in
Cass Lake, MN:  0.26 in
Butternut, WI:  0.26 in
Winter, WI:  0.19 in
Hayward, WI:  0.18 in
Grand Marais, MN:  0.16 in
Hibbing, MN:  0.15 in

Weather Synopsis

Cold front has been making slow but steady progress to the south/east this afternoon.  At 6 PM the cold front extended from west-central Lake Superior to western Wisconsin to southern Minnesota.  Waves of strong to severe thunderstorms have been affecting northwest Wisconsin back into far eastern Minnesota this afternoon with some rain and embedded thunderstorms occurring north of the cold front in the cooler air in north central Minnesota.

Heavy rainfall rates of up to 3 inches in an hour or less have been reported with the storms this afternoon in parts of eastern Minnesota and northwest Wisconsin, there has also been reports of downed trees and power lines in northwest Wisconsin.

Rain and thunderstorms continued over northeast Minnesota and northwest Wisconsin as of 7 PM but this area of rain is ending from SW-NE and should move out of our area before 10 PM, mostly cloudy to partly cloudy skies will occur overnight with a few showers possible.  Lows will range from the 40s in northern Minnesota to the mid 50s to around 60 degrees in eastern Minnesota and northwest Wisconsin.

Much cooler temperatures for Tuesday under mostly cloudy skies, highs will range from around 50 degrees in northern Minnesota to the 60s in eastern Minnesota and northwest Wisconsin.  Could see a few showers or some patchy drizzle around the area Tuesday but no heavy rain or severe weather is expected.

Wednesday looks mainly dry with highs ranging from the upper 50s to around 70 degrees with the warmest temps in northwest parts of the area, around International Falls and Bigfork.

Southerly winds develop late this week as low pressure approaches from the west — Warmer temps and more moisture advecting into the Northland with increasing amounts of instability will likely generate some showers and thunderstorms over parts of the Northland especially from Thursday night into Friday, but a few showers could develop as early as Thursday afternoon.

Duluth, Minnesota Climate Normals for August 28

High:  72
Low:   53

Sunrise Tuesday:  6:23 AM CDT
Sunset Tuesday:   7:56 PM CDT