Area Forecast Discussion
Issued by NWS Duluth, MN

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45
FXUS63 KDLH 250842

Area Forecast Discussion
National Weather Service Duluth MN
342 AM CDT Fri May 25 2018

.SHORT TERM...(Today through Saturday)
Issued at 341 AM CDT Fri May 25 2018

The forecast focus through Saturday will continue to be on
shower/thunderstorm chances as a few different shortwaves move
through the region.

Much of the thunderstorms were just south of the Northland as of
0830Z, but there were stronger storms moving out of the Twin
Cities/west central Wisconsin region which will likely affect
portions of northwest Wisconsin early this morning. Area 88D`s
show a veering low level jet of 30-35 knots into northwest
Wisconsin. The storms this morning over northwest Wisconsin could
be strong with some producing small hail. A few showers and
storms can`t be ruled out further north and west either in this
moist and unstable airmass. A shortwave embedded in an upper
trough will move into the region today arriving in far eastern
Minnesota and northwest Wisconsin during peak heating. Low level
convergence will not be very strong as seen in the RAP`s 0-1KM
wind field. However, plenty of instability will be in place with
surface dewpoints this afternoon in the lower to middle sixties
over northwest Wisconsin. This should yield MLCAPE around 2000
J/KG. As has been the case, shear will be lacking but 0-6KM values
may approach 30 knots. Additional storms will develop as the
upper wave moves in and we have chances highest this
afternoon/evening over northwest Wisconsin. There will be a risk
for a few severe storms, especially from eastern Minnesota into
northwest Wisconsin with northwest Wisconsin having the best
chance. Today will be warm with highs in the lower to middle

The chance for showers/storms will end or diminish this evening
over much of the Northland from west to east. However, another
shortwave is forecast to move along the International Border
bringing a chance for more showers and storms, mainly over far
northern Minnesota.

A trough over northeast Minnesota/Lake Superior/northern Wisconsin
will keep the threat for a few showers/storms on Saturday over
those areas, with the Walker, Brainerd Lakes, Aitkin, Siren areas
expected to be dry. It will again be quite warm with highs in the
eighties for most areas.

.LONG TERM...(Saturday night through Thursday)
Issued at 341 AM CDT Fri May 25 2018

Little change in the on-going theme of the long-term forecast, with
more chances of showers and thunderstorms, along with some very warm
and humid conditions, particularly Sunday and Monday.

Saturday night and Sunday will have some lingering chances of
showers, and possibly a thunderstorm, as the remnants of a mid-level
shortwave trough exits the region. Northwest flow aloft and mid-
level ridging will take its place during the day Sunday. Very hot
conditions are looking more likely with abundant sunshine, and a
warm and humid air mass in place. The ridging will provide good
subsidence to stave off cloud cover for most of the day, with highs
reaching into the upper 80s and even the lower 90s for some
locations. Westerly flow will also stave off any lake breeze that
otherwise would develop, so even areas along Lake Superior will get
in on the heat.

Then, an upper-level cut-off low develops over the Intermountain
West states, and slowly advances eastward over the region, with an
associated surface low meandering into the region. Upper-level
diffluence forms on the leeward side of the trough, bringing deeper
overall lift to support chances of showers and storms. There`s some
disagreement in the GFS/ECMWF/GEM models regarding the areal
coverage of precipitation and the amount of instability available
for fueling convection. Due to the uncertainty, leaned towards the
consensus model blends for PoPs, which keep chances of showers and
storms in the region through the day Wednesday.

Cold air advection moves into the region on the backside of the
surface low, with 925 mb temperatures dipping into the 15 to 20
degree C range. The main consequence of this will be some cooler
temperatures for Thursday and Friday - a break from the balmy
temperatures we are expected to experience Sunday through Wednesday.
Highs Thursday and Friday will return to the middle to upper 70s,
which is still slightly above seasonal averages.


.AVIATION...(For the 06Z TAFS through 06Z Friday night)
Issued at 1222 AM CDT Fri May 25 2018

A complex low pressure system will continue to affect the
Northland throughout the period. Showers and thunderstorms will
develop in association with the system, especially in the afternoon
and early evening on Friday. While conditions are largely expected
to be VFR, there could be some MVFR CIG`s and VSBY`s in association
with showers and thunderstorms.


DLH  85  58  85  53 /  40  20  20  10
INL  85  55  82  52 /  30  50  30  10
BRD  87  58  88  57 /  30  10   0   0
HYR  86  58  89  55 /  50  30  20  10
ASX  85  57  80  49 /  50  20  30  10


LS...Dense Fog Advisory until 10 AM CDT this morning for LSZ140>145.



AVIATION...DAP/JTS is the U.S. government's official web portal to all federal, state and local government web resources and services.