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fxus63 kdlh 211130 
afddlh

Area forecast discussion
National Weather Service Duluth Minnesota
630 am CDT Thu Jun 21 2018

Update...
issued at 622 am CDT Thu Jun 21 2018

Updated for the 12z aviation discussion below.

&&

Short term...(today through friday)
issued at 359 am CDT Thu Jun 21 2018

Continued dry conditions expected across the Northland through
tonight as high pressure over southern Ontario Canada remains in
control. Surface low pressure situated over northwestern Iowa this
morning will continue to bring a shield of cirrus clouds north into
the region, but dry air near the surface will keep any precipitation
that moves northward at Bay. Another lake breeze will develop today,
so temperatures will be cooler Lakeside, with highs ranging from the
middle to upper 60s along Lake Superior, and into the upper 70s and
lower 80s further inland. Clear skies and light winds will be in the
picture for tonight, so looks like a good night for radiational
cooling, so lowered overnight temperatures by a degree or two.
Overnight lows will dip into the upper 40s to lower 50s Lakeside,
with middle to upper 50s further inland.

A weak mid-level impulse will then eject from a shortwave trough
that is progged to develop over the intermountain west states for
Friday. The primary consequence of this wave looks to be an increase
in cloud cover from west to east Friday afternoon. There are some
small chances of showers and perhaps a thunderstorm as better
instability develops due to steepening low-level lapse rates. MUCAPE
values range between a few hundred up to 500 j/kg, so instability
will remain on the low side, but still think there could be a few
rumbles of thunder along the international border region. New
rainfall amounts should remain light as well, with only up to one-
tenth of an inch of quantitative precipitation forecast anticipated.

Long term...(friday night through wednesday)
issued at 359 am CDT Thu Jun 21 2018

The long-term begins with weak high pressure over the northland;
however, the quiet weather will only be brief as a cold front begins
to move down from Canada. This front will slowly decay over the area
but will bring a chance of rain showers throughout much of the
weekend. Overall, quasi-geostrophic fields show a general large
area of enhanced lift though instability is a limiting factor and
the lack of upper level support also will limit shower
development. Have only included pops up to about 50% throughout
the weekend with timing of the front being the main uncertainty
due to its decaying nature.

High pressure builds strongly on Monday and Tuesday before another
low pressure system moves through the area by mid-week. This
system also brings potential for more rainfall, but nothing too
extraordinary. Overall very little impactful weather throughout
the extended period.

&&

Aviation...(for the 12z tafs through 12z Friday morning)
issued at 630 am CDT Thu Jun 21 2018

VFR conditions through the taf period. Winds will remain easterly
through the day, with gusts around 17 kts at kdlh due to
favorable fetch at the head of Lake Superior. Otherwise, winds
will remain below 10 knots elsewhere.

&&

Preliminary point temps/pops...
dlh 70 51 79 55 / 0 0 0 10
inl 84 58 84 59 / 0 10 20 20
brd 78 55 80 59 / 0 0 0 10
hyr 77 50 80 54 / 0 0 0 0
asx 66 48 75 51 / 0 0 0 0

&&

Dlh watches/warnings/advisories...
WI...none.
Minnesota...none.
Ls...none.
&&

$$

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