Sunday, September 11, 2016

Warm start to September continues in Duluth with the average temperature nearly 6 degrees above normal

/Issued 5:18 PM CDT, Sunday, September 11, 2016/

Weather headlines for Duluth for the next few days

There is a chance for some frost Tuesday night in parts of the Northland for locations away from Lake Superior - Nothing unusual for a frost in mid September.  The map below shows the average date for the first fall freeze.  

Darker blue:  Sep 11-20
Lighter blue:  Sep 21-30

Getting to be that time of year when vibrant colors begin to appear.  The map below shows the time frame for peak fall foliage in Minnesota.

In Duluth late September to early October is when peak conditions typically occur, a little earlier in northern Minnesota.  Of course not all years are the same, will see what happens this year.

Surface forecast map valid for Friday, September 16, 2016.  Source, Weather Prediction Center.  Still a lot of time for things to change, but right now it looks like there could be some rain in the Northland sometime between Thursday-Saturday, September 15-17.

Tonight's low temperature forecast.

Monday's high temperature forecast.

Last week's temperature departure map.

Last week's precipitation departure map.

Temperature and precipitation report for Duluth, MN (Airport location)

September 4-10, 2016

High temperatures:

9/4:  77 F/+7 degrees above normal
9/5:  80 F/+11 degrees above normal
9/6:  79 F/+10 degrees above normal
9/7:  69 F/Normal
9/8:  73 F/+5 degrees above normal
9/9:  73 F/+5 degrees above normal
9/10:  68 F/+1 degree above normal

Low temperatures:

9/4:  57 F/+6 degrees above normal
9/5:  63 F/+13 degrees above normal
9/6:  61 F/+11 degrees above normal
9/7:  59 F/+9 degrees above normal
9/8:  57 F/+8 degrees above normal
9/9:  55 F/+6 degrees above normal
9/10:  51 F/+3 degrees above normal

Total precipitation:  2.17"
Normal:  0.98"
Departure:  +1.19" above normal

Weather Summary for northeast Minnesota and northwest Wisconsin
Date:  September 11, 2016

A very nice day although a tad on the windy side with south-southwesterly winds in the 10 to 20 mph range with gusts to around 30 mph, but these gusty south winds also brought warmer temperatures back to the Northland today with highs in the 70s which is 5-10 degrees warmer than normal for this time of year.  Sky conditions varied between partly and mostly sunny today.  Weather map late this afternoon had high pressure over the Ohio Valley with a cold front over the northern Plains.

Forecast Discussion for northeast Minnesota and northwest Wisconsin

...Short Term Forecast...

Tonight (September 11)

Partly cloudy skies.  Patchy fog is possible late.  Low temperatures mainly in the 50s with south or southwest winds at 10 to 15 mph with higher gusts through early evening.

Monday (September 12)

A cold front is forecast to reach a line from northern to west central Minnesota by Monday morning - This front will continue to move to the east/southeast through Monday night, exiting northwest Wisconsin after midnight.  

Along and ahead of this front dew points are forecast to rise into the upper 50s or lower 60s with PWATS ranging from around 1.00-1.50".  

Mid level lapse rates are expected to range from 7.0-8.5 c/km with CAPE at around 1000 j/kg or less with eastern Minnesota and northwest Wisconsin possibly having the greatest instability on Monday based on the latest model data.  

Southwest low level jet of 30-40 knots should continue on Monday aimed primarily at northwest Wisconsin.  

Looks like will be dealing with a cap tomorrow which is quite normal for September with 700mb temperatures at around +10 degrees Celsius.

Will probably see some showers develop over parts of the Northland tomorrow due to the cold front moving through the area.  A few thunderstorms are also possible especially during the afternoon-evening hours in eastern Minnesota into northwest Wisconsin.  Not expecting any severe weather at the moment although the amount of wind shear does look decent tomorrow, but the cap plus the marginal amount of instability will probably play a role in keeping any thunderstorm below severe levels.

Highs on Monday will be in the 60s and 70s with lows Monday night in the 40s and 50s.  Winds tomorrow will be out of the south or north with winds tomorrow night shifting to the north/northwest area-wide.  Wind speeds on Monday will range from 10 to 20 mph.

...Extended Forecast...

Tuesday (September 13)

A brief cool snap moves in on Tuesday with highs in the 50s and 60s, lows Tuesday night will be in the 30s and 40s.  Areas of frost are possible late Tuesday night-early Wednesday morning over parts of the Northland but locations near Lake Superior shouldn't have to worry about any frost just yet.  Cold front will be centered well to our east on Tuesday with high pressure building in from the northern Plains and central Canada.  Note:  A fair amount of cloud cover is expected on Tuesday with a possibility for some showers.  Skies should gradually clear Tuesday night.

Wednesday (September 14)

Quiet weather with high pressure in control.  Highs on Wednesday will mainly be in the 60s which is where they should be for mid September.

Forecast for Duluth and Superior

.Tonight...  Partly cloudy.  Low 55 to 60.  Wind south to southwest at 10 to 20 mph.

.Monday...  Mostly cloudy.  Showers possible mainly during the afternoon.  High 68 to 73.  Wind southwest at 10 to 15 mph.

Normal temperatures for Monday

High:  67
Low:   48

Sunrise Monday:  6:43 AM CDT
Sunset Monday:   7:25 PM CDT