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fxus63 kdlh 190520 

Area forecast discussion
National Weather Service Duluth Minnesota
1220 am CDT Thu Jul 19 2018

Short term...(this evening through thursday)
issued at 311 PM CDT Wed Jul 18 2018

Increasing clouds today and tonight ahead of a low pressure system
approaching the upper Midwest. Showers and thunderstorms are
expected to develop from south to north through the day on Thursday,
though parts of northwest Wisconsin near the u.P. And parts of the
Minnesota arrowhead might remain dry through the daytime hours on Thursday.
While there will be some instability associated with the initial
wave of precipitation on Thursday which could lead to a few embedded
storms, overall the threat for storms is low as a broad area of
light/moderate rain advects into east-central Minnesota and adjacent areas
of northwest WI on Thursday. Temperatures cooler due to the east winds
ahead of the surface low deepening to the south on Thursday - highs
in the upper 60s to mid 70s. Not bad considering the next seven days
are usually the warmest of the year compared to the 1981-2010 normal
values for highs and lows at dlh. (The normal high temperature of
77f is the highest value for the year at Duluth July 19-25.)

On the synoptic scale a 80-90 knot upper level jet streak stretching
from the Pacific northwest into the central Great Plains will
produce upper level divergence over the northern plains/upper
Midwest, which will help to deepen a mid-level shortwave trough
tracking across the northern plains today into tomorrow. The
relatively slow-moving mid-level feature will result in a deepening
surface low across central/southern Minnesota on Thursday, with warm air
advection at low levels ahead of the low leading to showers and
storms. While there remains some variability in model solutions as
to the track of the low, guidance has been trending a bit further
south in most solutions, which would limit the amount of convection
that reaches the Duluth County Warning Area. The most likely scenario at this point
is for a broad area of light/moderate rain to advect north into east-
central Minnesota during the day Thursday - perhaps not until the afternoon
- with few embedded storms possible. There will be ample low
level moisture combined with strong broad-scale lift as the
approaching mid- level shortwave trough deepens into a closed low
which should result in decent rainfall rates for parts of the
region, leading to daytime rainfall amounts of a quarter to half
inch, locally higher in parts of north-central Minnesota where
rain will be falling for most of the day.

Long term...(thursday night through wednesday)
issued at 311 PM CDT Wed Jul 18 2018

The upper low will continue to send waves of showers and a few
thunderstorms our direction through Saturday as it slides from
southwest Minnesota southeast to northern Illinois on Friday, and on
to Indiana by Saturday. Have kept pops in the chance-likely range
Thursday night and Friday, gradually tapering off to slight pops on
Saturday. The cloud cover and showers on Friday will keep
temperatures on the cool side with highs only in the mid 60s to mid
70s, and overnight lows in the 50s both nights. Saturday should be
a little warmer with a bit more sunshine, but not by very much.
Sunday looks dry and quiet with a ridge sliding across the area.

On Monday a cold front slides through the area, with reasonably
close timing between the models. We have some chances for showers
and storms, though the best potential for thunder is closer to the
low up in Canada. Temperatures Monday will be warmer again with
highs in the mid 70s to around 80. Tuesday we should have another
lull day with highs back in the 70s with dry conditions. Wednesday
there is an approaching cold front with an upper low in Canada, but
there is poor agreement between models on this feature, and have
stuck with the consensus forecast of small pops and near normal


Aviation...(for the 06z tafs through 06z Thursday night)
issued at 1220 am CDT Thu Jul 19 2018

High pressure will gradually move out of the region during the
taf period, as low pressure moves in from the south and west. The
low pressure system will bring increasing clouds, and the chance
of showers and spotty thunderstorms to much of the region. The
best chance of precipitation will be in the kbrd area. VFR
conditions will gradually give way to areas of MVFR cig's and
vsby's during the day Thursday.


Preliminary point temps/pops...
dlh 57 70 59 72 / 0 70 40 50
inl 60 80 60 76 / 0 30 30 50
brd 62 70 61 77 / 20 90 70 40
hyr 58 74 61 73 / 10 40 50 50
asx 57 77 58 70 / 0 30 50 40


Dlh watches/warnings/advisories...


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