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Area forecast discussion 
National Weather Service Duluth Minnesota
323 PM CDT Tuesday Sep 1 2015

Short term...(this evening through wednesday)
issued at 323 PM CDT Tuesday Sep 1 2015

High pressure was located over the forecast area at 1930z. Clouds
covered a portion of the region thanks to the pineapple express
feeding plenty of moisture into the western Great Lakes. Shortwave
energy was lifting northeastward through eastern South Dakota and generating some
showers into west central Minnesota with an isolated thunderstorm. Expect this
activity to reach the southern tier of the forecast area by 02z.
However...plenty of dry air over the region will keep the activity
in check. Have some small probability of precipitation along the southern tier where its
expected to hang together this evening. A better chance of
thunderstorms overnight as shortwave energy rides up the west side
of the upper ridge that's currently over the Great Lakes. Models are
offering different scenarios for timing and placement of any storms
and their quantitative precipitation forecast. Tried to blend with surrounding offices for probability of precipitation/quantitative precipitation forecast
late tonight.

Model differences continue on Wednesday. Even the hires models are
having a difficult time trying to resolve where and when
thunderstorms affect the area. Regardless...the upper level
shortwave continues on its northeastward trajectory and will impact primarily
northwest WI. Have some low probability of precipitation elsewhere as arw model has some activity
nearby. Used a blended approach for Wednesday.

Long term...(wednesday night through tuesday)
issued at 323 PM CDT Tuesday Sep 1 2015

Weak upper short wave will be exiting the Northland to the east Wednesday
night/Thursday morning as a high amplitude ridge builds across the northern
plains and upper Midwest. This lingering short wave will keep a slight
chance of showers and storms across northwest WI through late Thursday
morning. Dry conditions under the warm upper ridge will develop and
last through Friday morning before a short wave lifts northeastward along the western
edge of the ridge across the Dakotas and western Minnesota Friday afternoon and
into western Ontario Friday night/Sat morning. A trailing front south of
the short wave/surface low will slide eastward across the Northland during
this time and produce areas of rain showers and scattered
thunderstorms. The front will stall out and phase with the next low
pressure system moving into the northern plains on Sunday and allow the
threat for showers and storms to persist through early Monday
morning. The parent upper low with this weekend system will remain
north of the international border...but allow for a fairly strong
push of cold air to infiltrate the region going into the beginning
of next week. The dry and cool air should keep precipitation chances to a
minimum...but overcast cloud cover is a strong likelihood.

Temperatures will remain warm Thursday through Saturday with highs
in the 80s...and overnight lows in the 60s. A gradual cool down will
begin on Sunday with highs in the 70s to near 80...and into the
upper 60s and 70s on Monday. Morning lows early next week will drop
into the 50s.


Aviation...(for the 18z tafs through 18z Wednesday afternoon)
issued at 1238 PM CDT Tuesday Sep 1 2015

A weak upper short wave will ride eastward through southern Minnesota into WI
tonight and trigger a few rain showers and possibly a weak storm
around the hyr region in the evening. Winds will be light from the
south/southeast with a east/NE wind off Lake Superior impacting dlh Wednesday
morning. Patchy fog will once again form around the region late
tonight and persist into Wednesday morning. VFR conditions will return
by late Wednesday morning and continue through the day.


Preliminary point temps/pops...
dlh 65 80 63 75 / 20 20 20 10
inl 56 85 64 87 / 20 20 10 10
brd 65 83 65 85 / 10 10 10 10
hyr 65 83 64 84 / 20 30 20 10
asx 62 82 60 83 / 10 30 20 10


Dlh watches/warnings/advisories...


Short term...gsf
long term...tentinger

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