Area Forecast Discussion
Issued by NWS Duluth, MN

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FXUS63 KDLH 211745

Area Forecast Discussion
National Weather Service Duluth MN
1245 PM CDT SUN AUG 21 2016

Issued at 1245 PM CDT Sun Aug 21 2016

Updated for the new 18Z Aviation Discussion below.

UPDATE Issued at 1139 AM CDT Sun Aug 21 2016

Colder air aloft and cyclonic flow has led to plenty of cumulus
clouds over much of the Northland as of late morning. There could
be a few showers that develop as well and we added a mention for a
time this afternoon to portions of northwest Wisconsin.


.SHORT TERM...(Today through Monday)
Issued at 337 AM CDT Sun Aug 21 2016

At 330 AM, skies ranged from mostly cloudy in the eastern half of
the CWA, to partly cloudy in the west. A few lingering showers
persisted in the west, with more widespread showers in the east.
It was much cooler in the areas that have seen some clearing,
with Crane Lake coming in at 43 degrees as of 3 AM. The
strengthening low over the central Great Lakes was resulting in
gusty winds across western Lake Superior.

The main focus for today will be the potential for lingering rain
showers in the eastern portion of the CWA, along with cloud cover.
Looks like the high pressure will be able to maintain a partly to
mostly sunny sky today, with conditions generally becoming mostly
sunny across the entire area as the day wears on. While there will
be some rain showers early, expect these to gradually end as well.

Return flow will already start to bring some WAA clouds into the
region tonight, along with a few showers in the International
Border region. Otherwise, skies will be clear to partly cloudy for
the southern portions of the CWA. The most clouds will be in the
north. Some showers could linger in the tip of the Arrowhead on
Monday morning, with increasing sunshine most areas. Winds will be
much more gusty from the south and southwest on Monday. Highs will
generally be in the 80s.

.LONG TERM...(Monday night through Saturday)
Issued at 337 AM CDT Sun Aug 21 2016

A positively tilted trough will dig and deepen from Alberta late on
Monday into the Northern Plains by Wednesday afternoon. Ahead of
the trough, an area of low pressure will develop across the eastern
Dakotas on Tuesday. A warm front will lift northwards across central
MN and northern WI on Tuesday to the International Border by late in
the day as suggested by the GFS/GEM. Still some uncertainty on the
exact placement/location of the front as the NAM/ECMWF keep the
front in Ontario rather than lifting through MN during the day. Kept
low POPs for the time being. Still think that regardless of where the
front is there may be some shower activity around with the low to
the west and strong WAA. Will see mild temperatures on Tuesday with
highs in the low to mid 80s, and it will be muggy with dew points in
the 60s.

The low across the eastern Dakotas will move northeastward into
Ontario on Wednesday. This will swing the lows associated cold front
through the CWA by Wednesday evening. This will bring better chances
of showers and thunderstorms. Will see a 1000-2000 J/kg of MLCAPE
Tuesday evening into early Wednesday ahead of the cold front moving
in. However, 0-6 km bulk shear is around 10-20 kts ahead of the front
with better shear values behind the front. Expect thunderstorms
Tuesday evening into early Wednesday, but expect the severe weather
threat to limited by deep layer shear. Will see readings in the 70s
on Wednesday.

Expect rain showers across portions of the region on Thursday as the
main trough axis will still be moving in. The trough will lift out
of the region late on Thursday/early Friday, which will allow high
pressure to build in providing dry weather for much of the CWA on
Friday.  Shower and thunderstorm chances return for the weekend as
another trough moves in from the west.


.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
Issued at 1245 PM CDT Sun Aug 21 2016

The VFR conditions will continue through Monday afternoon.
The scattered/broken cumulus around 5 to 7 kft, as of early this
afternoon, will gradually clear later this afternoon into this
evening as high pressure moves into the region.

Southerly flow will develop tonight in the wake of the passing
high pressure to the east. A warm front will be near far northern
Minnesota and the Ontario/Manitoba border. A band of light rain
will likely cut east across the international border area during
the middle of the night, possibly bringing very light rain to KINL
around midnight. Left it out at this time since the rain will
likely have little impact.

A strong southwesterly low-level jet, of about 30 to 50 knots in
the 1 kft to 2 kft layer, will develop later tonight from west to
east. The northeast Minnesota terminals can expect a period of
significant low-level wind shear late tonight until a couple
hours after sunrise. Considered adding LLWS to KHYR, too, but not
confident the LLWS will be strong or lengthy enough to add at this

Gusty south-southwest flow will begin to develop late Sunday


DLH  70  53  81  62 /   0  10  10  20
INL  71  52  84  61 /   0  20  10  10
BRD  72  55  83  64 /   0   0  10  20
HYR  69  49  80  63 /  20   0  10  20
ASX  71  52  84  64 /  10  10  10  20


.DLH Watches/Warnings/Advisories...
LS...Small Craft Advisory until 4 PM CDT this afternoon for LSZ148.



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