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fxus63 kdlh 190839 

Area forecast discussion
National Weather Service Duluth Minnesota
339 am CDT Sat Oct 19 2019

Short term...(today through sunday)
issued at 339 am CDT Sat Oct 19 2019

Mild and mainly dry weekend weather after a weak cold front moves
through this morning.

A weak cold front will move from west to east across the Northland
today leading to a chance for a few hours of light rainfall across
parts of the region, mainly east-central Minnesota and all of
northwest Wisconsin early today. Total rainfall amounts less than a
tenth of an inch in northwest Wisconsin, just a few hundredths if
anything in eastern Minnesota. Skies then clear out as a weak area of high
pressure builds across the Midwest Saturday afternoon into Saturday
night. West winds 10-15 mph in the wake of the cold front day with
high temperatures again mild like yesterday, in the upper 50s to low
60s. Clear skies tonight and winds going calm with lows will fall
into the mid 30s, most spots remaining above the freezing mark.

A sunny start to Sunday then increasing clouds from west to east
late. A bit of a slower trend in the low pressure developing across
the Great Plains has lead to precipitation chances have been pushed
later a bit until late Sunday evening. Light southeast winds ahead
of the developing low pressure system at around 5 mph. Highs in the
mid 50s to near 60, remaining above normal.

Long term...(sunday night through friday)
issued at 339 am CDT Sat Oct 19 2019

A strong area of low pressure will deepen across the northern Great
Plains late Sunday, slowly approaching Lake Superior on Monday
before weakening and drifting northward over northern Ontario
towards Hudson Bay into mid-week. Overall there have been no
dramatic changes in recent model guidance, with some of the
deterministic guidance coming in slightly lower on quantitative precipitation forecast amounts and a
somewhat odd trend in the gefs with ensemble spread actually
increasing on a run-to-run basis. Otherwise though forecast remains
fairly unchanged with high confidence in strong winds in the wake of
the low on Tuesday and at least an inch of precipitation between
Sunday night and Tuesday. Precipitation type through Tuesday will be
mainly rain given warmer surface temperatures. There remains a low
chance for some embedded thunderstorms, with the best chance in
northwest Wisconsin on Monday afternoon as the surface low moves
across Western Lake Superior. Highs in the 50s Monday, then in the
40s on Tuesday as the low moves north of Lake Superior and cooler
air moves in from the northwest. Winds northwest 15-25 mph with
gusts to 35-45 mph on Tuesday in the wake of the low.

Mid to late week a cool and cloudy pattern with occasional chances
for light precipitation, a mix of rain and snow. While cooler air
will advect in from the northwest late week, the air will not be
exceptionally cold with 850mb temps only around -5c to -8c, which is
slightly below normal for late October but far from unusual. With
sufficient low level moisture in place, there will be occasional
chances for light rain/snow showers through Thursday, especially in
far northern Minnesota where the cool northwest flow could even
result in some lake effect snow showers from Inland Lakes. However,
precipitation amounts will be very light overall, with little if any
snowfall accumulation anticipated. Dry late Thursday into Friday as
high pressure builds in, with warmer temps approaching for Friday as
a warm front moves from west to east across the northern Great
Plains. Highs in the 40s Wed/thurs/Fri, except for a few spots in
the upper 30s on Thursday. Lows in the upper 20s to near 30, coldest
Thursday night as skies clear out for a bit and some spots fall to
the mid 20s or perhaps in the low 20s.


Aviation...(for the 06z tafs through 06z Saturday night)
issued at 1155 PM CDT Fri Oct 18 2019

Main concern continues to be low level wind shear as a 50 kt 850 mb jet crosses
tonight. Slowed down frontal timing a bit per latest model
guidance and also maintained the no IFR approach as guidance
trends downward on the chance for IFR. Winds will switch through
the period, and become gusty Saturday afternoon, but overall
decent flying conditions.


issued at 339 am CDT Sat Oct 19 2019

This morning persistent south-southeast winds will lead to building
waves along parts of the North Shore, with a Small Craft Advisory in
effect north of Grand Marais for some building waves. Once the cold
front moves through winds will be southwest to west and on a
weakening trend through Sunday, around 5-10 knots tonight then less
than 5 knots on Sunday morning.

Late Sunday through Tuesday a strong low pressure system will
approach and move across Western Lake Superior leading to very
strong winds and large waves. Easterly winds ahead of the low Sunday
night into early Monday will lead to dangerous conditions for small
craft as waves build to 6 to 8 feet along parts of the North Shore
with east winds around 20 to 25 knots. As the low moves across the
lake Monday evening winds will switch to become west-northwesterly
and rapidly increase to sustained 20 to 30 knots on Tuesday
afternoon with gale force gusts likely. These strong west winds
linger into Wednesday. A Gale Warning may be needed for much of the
Western Lake Superior nearshore waters on Tuesday, with otherwise
small craft advisories needed between Monday and Wednesday for all


Preliminary point temps/pops...
dlh 59 40 57 43 / 30 0 0 60
inl 59 36 56 42 / 0 10 10 40
brd 60 37 58 44 / 10 0 10 70
hyr 59 36 59 46 / 70 0 0 60
asx 60 38 60 43 / 70 0 0 50


Dlh watches/warnings/advisories...
Ls...Small Craft Advisory until 4 am CDT early this morning for

Small Craft Advisory until noon CDT today for lsz140.



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