Area Forecast Discussion
Issued by NWS Duluth, MN

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FXUS63 KDLH 230557
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
1257 AM CDT FRI SEP 23 2016

.UPDATE...
Issued at 908 PM CDT Thu Sep 22 2016

Added some showers/sprinkles across parts of northern Minnesota
late tonight into early tomorrow. While there is a significant
amount of dry air across the international border in northeast MN
associated with the surface high moving into far northwest
Ontario, moisture advecting in across northern Minnesota ahead of
a warm front will likely result in some sprinkles or light rain
showers by early morning based on current trends and short-range
guidance. Otherwise just made some minor adjustments to
temperatures and winds.

&&

.SHORT TERM...(This evening through Friday)
Issued at 342 PM CDT Thu Sep 22 2016

High pressure of western Manitoba this afternoon has brought north
to northeast winds across the area this afternoon and a slow
decrease in the dewpoints across the area from early this morning.
Much of northern Minnesota has broken out into sunshine with clouds
still lingering over northwest Wisconsin and central Minnesota.
There is still some patchy fog &/ drizzle from Ashland to Ironwood,
but this too should continue to dissipate this afternoon as long as
satellite trends continue.

Tonight this ridge of high pressure to continue to slide east,
keeping conditions dry across the area.  Clear skies should continue
for most of northern Minnesota, with clouds remaining across the
southern portions of the area.  Have gone with colder MOS guidance
across the north where clear skies should continue, with warmer
values south where clouds will remain.

Friday the developing low pressure system over eastern Colorado will
strengthen and cause our winds to begin turning more easterly during
the day as the pressure gradient increases.  This is going to cause
stronger winds on and near Lake Superior, though only a little gusty
on land.  The warm air advection and approaching warm front is going
begin bringing chances for showers into the southwest by Friday
afternoon.  There is not much CAPE available so have gone with only
isolated thunder, expecting better thunder chances south of the
forecast area.  Highs near Lake Superior will colder with the breezy
onshore flow and may only get into the 50s, with low to mid 60s
elsewhere.

.LONG TERM...(Friday night through Thursday)
Issued at 342 PM CDT Thu Sep 22 2016

Upper level ridging covers the forecast area Friday night.
Meanwhile, the associated surface high drifts off to the northeast
into Ontario. This allows a surface low center to get organized in
the western Dakotas, while an upper level low begins to cut off from
the rest of the flow aloft. A warm air advection pattern sets up
between these features and the warm front pushes through much of the
area. Showers and isolated thunderstorms will occur along and ahead
of the warm front. The warm front reaches the Arrowhead by 18Z/1pm
Saturday and exits the area by evening. Showers will still be found
near the front. In the meantime, the cut off low deepens as it
slowly moves northward. Instability is lacking near the departing
warm front, but increasing as a cold front begins to push into
western Minnesota. Thunderstorm chances increase ahead of the front.
The cold front marches through the area Saturday night and departs
on Sunday. Models show large differences Sunday night through
Wednesday. The GFS deepens the cut off low and drops it over the
region. The ECMWF moves it through Manitoba and into Ontario and
quickly. Used a consensus approach to weather elements to account
for these differences.

&&

.AVIATION...(For the 06Z TAFS through 06Z Friday night)
Issued at 1257 AM CDT Fri Sep 23 2016

A mix of VFR to MVFR conditions expected through the TAF period as
a warm front approaches from the southwest. At DLH MVFR ceilings
may develop late tonight into early Friday morning, but confidence
is lower given the abundant dry air to the north. At HIB and INL VFR
through the period due to high pressure to the north with only VFR
clouds. BRD will be impacted by the warm front approaching tonight
into tomorrow with a few rounds of light rain showers/sprinkles early
this morning and through the day. Also with additional low level
moisture, MVFR ceilings are expected to develop at BRD and persist
through the day Friday.

Winds will become out of the east this morning, becoming breezy
today. Winds will be strongest at DLH and BRD with gusts to around
20 knots expected at both sites, though by the afternoon wind gusts
may not be as strong.

&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  51  62  56  65 /  40  10  70  40
INL  50  66  57  65 /  50  20  60  30
BRD  56  70  56  65 /  40  40  70  10
HYR  54  68  59  68 /  40  20  70  60
ASX  51  67  57  68 /  30  20  70  60

&&

.DLH Watches/Warnings/Advisories...
WI...None.
MN...None.
LS...Small Craft Advisory until 10 PM CDT this evening for LSZ121-
     144>148.

     Small Craft Advisory until 4 AM CDT Saturday for LSZ141>143.

&&

$$

UPDATE...JJM
SHORT TERM...LE
LONG TERM...GSF
AVIATION...JJM



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