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Area forecast discussion...updated 
National Weather Service Duluth Minnesota
1226 am CDT Tuesday Jun 30 2015

Update...
issued at 1226 am CDT Tuesday Jun 30 2015

Updated for the 06z aviation discussion below.




Update issued at 823 PM CDT Monday Jun 29 2015

Cold front was moving through NE Minnesota and headed for northwest WI at 01z.
Still some instability in the neighborhood which is combining with
short wave energy over Western Lake Superior to generate some
isolated to scattered showers and storms. They are much weaker then earlier
today and will continue to diminish with the loss of solar. Made
some adjustments to account for these trends.

&&

Short term...(this evening through tuesday)
issued at 340 PM CDT Monday Jun 29 2015

The cold front was draped across the Minnesota arrowhead late
this afternoon. Strong thunderstorms were over the southern
sections across Pine County and into Washburn County. Diurnal
storms have been popping up north of the border in Canada and
elsewhere in the The Arrowhead. Expect these diurnally driven
airmass storms to dissipate toward sunset. Still have some good
instability in place with MUCAPES 1500 to 2000 g/kg...but shear
has been decreasing as per Storm Prediction Center mesoanalysis. Still cannot rule out
some small hail. As high pressure will provide clearing skies
overnight...and we can expect some fog to develop especially in
The Arrowhead and northwest WI where condensation pressure
deficits and dew point depressions will be very low.

Tuesday will see sunshine once the fog lifts.

Long term...(tuesday night through monday)
issued at 340 PM CDT Monday Jun 29 2015

Ridge-trough pattern across the Continental U.S. Moderates through the week
with the ridge in the west retreating to the Desert Southwest
allowing a number of disturbances to move across the northern
plains/Canada border and into the upper Midwest. Temperatures will
be on a rising trend through the week and into the weekend.

Wed/thurs...a broad area of high pressure across Lake Superior will
result in quiet sensible weather...with seasonable to mild temperatures and
dry conditions. Winds light.

Thurs/Fri...high pressure drifts east over the lower Great Lakes
with a weak surface low/trough moving south out of Canada behind it.
This will result in a chance of precipitation across much of the County Warning Area...with
the best chances across The Arrowhead region. Best timing looks to
be Thursday afternoon into early Friday. Temperatures warmer as southerly
low/middle level winds advect in warmer air...highs middle to upper 70s.

Sat...will likely see a lull in precipitation chance for the Fourth of July
Holiday with mostly sunny skies and light winds. Temperatures warmer in the
upper 70s.

Sun...a low pressure system across central Saskatchewan/Manitoba with
associated cold front draped across the northern plains will result
in increasing precipitation chances for Sunday. Southerly flow ahead of the
front will result in warm temperatures...flirting with the low 80s in most
locations. Model agreement is fairly good for this time range with
the European model (ecmwf) further south than GFS....so feel confident in precipitation
chances. Better instability and stronger winds aloft could lead to
some organized storms...but a bit too far out to get more specific.

&&

Aviation...(for the 06z tafs through 06z Tuesday night)
issued at 1226 am CDT Tuesday Jun 30 2015

There may be reductions in visibility and cloud ceilings early
this morning at NE Minnesota and northwest Wisconsin terminals. Fog and
low stratus could cause periods of LIFR/IFR/MVFR conditions. The
khyr and kdlh areas are the most likely to be affected...while not
confident enough in any reductions at the kinl/khib/kbrd areas to
forecast anything other than VFR conditions at this point. The fog
and stratus will lift later this morning...but it could linger at
kdlh and khyr until late this morning. Once the VFR conditions
return late this morning...the VFR is expected the rest of the
day.

&&

Preliminary point temps/pops...
dlh 49 73 52 75 / 0 0 10 10
inl 47 78 53 77 / 0 10 10 30
brd 52 75 54 78 / 10 10 10 20
hyr 43 74 51 77 / 0 0 10 10
asx 44 71 50 74 / 0 0 10 0

&&

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

$$

Update...grochocinski
short term...clc
long term...jjm
aviation...grochocinski

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