Area Forecast Discussion
Issued by NWS Duluth, MN

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FXUS63 KDLH 232339

Area Forecast Discussion
National Weather Service Duluth MN
639 PM CDT Sun Jul 23 2017

.SHORT TERM...(This evening through Monday)
Issued at 326 PM CDT Sun Jul 23 2017

The upper low that has kept us busy for a few days over eastern
Lake Superior will continue to move east over the next 24 hours,
allowing a surface ridge of high pressure to build into the area
tonight and Monday. This evening, the cumulus clouds that are over
the area should dissipate with sunset. The area that remains more
stratus in nature is the concern, mainly hanging out over
northwest Wisconsin as of issuance time. Some models push it south
this evening, others are maintaining it in some form or another
overnight, kind of stuck in the col of the surface ridge building
in. Am currently favoring having it continue to push south as we
have seen going on this afternoon, so have styled sky grids in
that way. However, due to the recent rainfall, lingering higher RH
and the light winds expect fog development tonight. Some areas
may need a fog advisory beginning around midnight tonight as long
as the clouds clear off. With all these cloud cover issues mins
were somewhat tricky. Where I am more confident of clearing have
pushed mins down a little, but otherwise only made small changes
to the forecast. Monday looks warmer with more sunshine than we
had today, and adjusted max temps up slightly.

.LONG TERM...(Monday night through Sunday)
Issued at 326 PM CDT Sun Jul 23 2017

A chance for strong to severe storms Tuesday into early Wednesday,
then seasonable temperatures and dry through the rest of the work
week as an area of high pressure builds across the Upper Great
Lakes. Next chance for precipitation arrives mid to late next

On the synoptic scale the recurrent ridging over the Rockies/Great
Basin region that has developed numerous times over the past few
weeks looks to develop once again late this week. Before that, a
compact mid-level shortwave trough will dig across the Canadian
Prairie region early this week with a resulting surface low pressure
over northern Manitoba Tuesday lifting east towards Hudson Bay
Tuesday night. A warm front will lift northeast across northern
Minnesota through the day Tuesday into northern Wisconsin late
Tuesday. This will result the warm sector across the Northland late
Tuesday, with moderately steep mid-level lapse rates resulting in
1000-2500 j/kg MUCAPE available by Tuesday evening. However, limited
surface heating is possible during the day Tuesday due stratus/light
rain showers developing Tuesday morning as the warm front lifts
across the region. However, given the availability elevated
instability and approaching cold front coming from the west
thunderstorms that develop in parts of western Minnesota could move
eastward into a fairly favorable environment for strong to severe
storms. The most likely location for this would be along the
southern periphery of the CWA - Brainerd Lakes to I-35 corridor,
east into northwest Wisconsin towards Hayward and Park Falls. The
Storm Prediction Center has placed the entire region within a slight
risk for severe weather due to the possibility of severe storms
Tuesday night.

The cold front associated with the Canadian low will move east into
northwest Wisconsin Wednesday perhaps resulting in a round of
morning to early afternoon showers and storms before finally exiting
Wednesday evening. High pressure will build across the region
through the rest of the week resulting in seasonable temperatures -
highs in the upper 70s to low 80s.


.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 638 PM CDT Sun Jul 23 2017

Clouds have been diminishing through the evening hours and we
expect that trend to continue for a few hours before some
redevelopment occurs. MVFR/IFR ceilings were most numerous over
northern Wisconsin but they were even diminishing in spots there.
High pressure will move across the region tonight passing
southeast Monday allowing the surface flow to become south to
southeast. Light winds will occur tonight and will lead to fog and
more stratus, with the stratus most likely around and just inland
from Lake Superior. The fog could be dense in spots but will lift
between 12Z and 15Z. VFR conditions are then expected through the
remainder of the period.


DLH  51  74  57  77 /   0   0  10  40
INL  53  79  60  77 /   0   0  20  60
BRD  51  77  63  82 /   0   0  20  40
HYR  50  77  58  80 /   0   0   0  30
ASX  49  76  56  80 /   0   0   0  30




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