Area Forecast Discussion
Issued by NWS Duluth, MN

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
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 46 47 48

000
FXUS63 KDLH 231723
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
1123 AM CST Tue Jan 23 2018

.UPDATE...
Issued at 1113 AM CST Tue Jan 23 2018

Please see latest Aviation Discussion for 18Z TAFS

&&

.SHORT TERM...(Today through Wednesday)
Issued at 254 AM CST Tue Jan 23 2018

Fairly quiet conditions expected today through the day Wednesday.
Now that the winter storm has passed to the east, the only lingering
precipitation chances today will remain along the Lake Superior
snowbelt region and the Gogebic Range of Iron county in northwest
Wisconsin for this morning. Precipitation types are a little
uncertain as Ironwood is reporting unknown precip and Manitowish
Waters is reporting light snow as of 08z this morning. The
RAP/NAM/GFS model soundings disagree somewhat on p-types, but I
suspect it will be either freezing drizzle or light snow, depending
on the development of dendrites in the low-levels as the thermal
profile cools. For right now, leaning more towards snow than FZDZ
for p-types, with only light snow accumulations possible. Otherwise,
these chances of precipitation will eventually diminish as drier air
settles into the region. Elsewhere, skies will be partly to mostly
sunny, with highs in the middle teens over the Arrowhead to the
lower to middle 20s elsewhere. High pressure over Hudson Bay, along
with weak mid-level ridging, will be in control through today.

Overnight, a weak shortwave will dive southeast from the
Saskatchewan/Manitoba Canada region, bringing cloudy skies,
especially over our western half of the forecast area. I`m
anticipating some clear skies will linger over the eastern areas of
the Northland, which will have an impact on tonight`s low
temperatures. Expecting the temps to be warmer over the west due to
the cloud cover, and more radiational cooling over the east with
clear skies/light winds. Overnight lows should range between the
single digits above zero over the east, with lower teens to the
west. As the shortwave advances eastward, there may be some small
chances of light snow over the Arrowhead region, but the soundings
indicate a lack of deeper saturation with this wave, so
precipitation amounts should be limited. There is a wind component
to this precipitation as well, as winds go more southerly ahead of
the wave. This could help to enhance lift along the North Shore of
Lake Superior, but the flow looks fairly weak, so anticipating the
wind to play a minor role in supporting precip. Only about a half
inch of new snow accumulation will be possible along the North
Shore. Skies will be partly to mostly cloudy through the day
Wednesday.

.LONG TERM...(Wednesday night through Monday)
Issued at 254 AM CST Tue Jan 23 2018

The extended forecast will be relatively quiet with an absence of
any strong storm systems affecting the Northland. Temperatures will
start out mild Thursday and Friday, then cool through the weekend.

An upper level ridge will extend from near the Four Corners region
north through Montana and into Saskatchewan and Alberta Wednesday
evening. This ridge will move east and pass through the Northland
Thursday night. Strong warm air advection will occur during this
time with 850MB temperatures climbing to 7C to 8C over southern
portions of the Northland by Thursday evening. This warm air
advection precedes an area of low pressure that will be in the
Northern Plains Thursday but will strengthen and lift north into
northwest Ontario Thursday. We expect mainly dry conditions
Wednesday night into Thursday night, although there could be some
lingering light snow showers over the Arrowhead Wednesday evening.
As the low tracks east through Ontario Friday, cold air advection
will develop. A light wintry mix may occur Friday into Friday
evening over mainly far northern Minnesota. High temperatures
Thursday will be in the upper twenties to lower thirties and be even
warmer Friday ranging from the mid thirties to mid forties. Cold air
advection will continue into Saturday as low level winds turn
northwest then to more northerly Saturday night. A period of lake
effect snow showers will occur Saturday into Sunday along the
snowbelt of the South Shore. Some accumulation will be possible,
especially over Iron County. Highs will cool to the teens to lower
twenties on Sunday.

The models diverge on their solutions late in the weekend into early
next week with the ECMWF having a deeper upper trough near or just
east of the Northland Sunday which will move east into Monday versus
a faster northwest flow aloft from the GFS. The ECMWF would lead to
a drier forecast Sunday/Sunday night but the GFS has chances for
light snow. We have small POPs over portions of the Northland then a
dry forecast for all areas other than the South Shore`s snowbelt
region.

&&

.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
Issued at 1113 AM CST Tue Jan 23 2018

The influence of a low pressure centered over the eastern Great
Lakes continues to have an impact across our region in particular
KHYR as snow has begun to diminish and skies will gradually
improve. A section of clearing with light clouds will impact the
remainder of the afternoon period with skies cleared at KHIB and
KINL while the remaining sites remain with a few clouds but skies
will generally remain VFR before IFR/MVFR conditions redevelop
tonight. As a ridge of high pressure moves into the area, winds
will become light and variable into the overnight period. There is
a chance for additional cloud cover across the north shore of
Lake Superior impacting conditions at KDLH during the overnight as
low level winds veer to southeast.


&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  22  11  24  15 /   0  10  10  10
INL  16   7  23  11 /   0  10  10  10
BRD  25  14  27  15 /   0  10   0   0
HYR  25   6  25  11 /   0  10  10  10
ASX  23   8  25  13 /  30  10  10  10

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
LS...None.
&&

$$

UPDATE...WM
SHORT TERM...JTS
LONG TERM...Melde
AVIATION...WM



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.