Area Forecast Discussion
Issued by NWS Duluth, MN
FXUS63 KDLH 241018 CCA
Area Forecast Discussion...CORRECTED
National Weather Service Duluth MN
418 AM CST Tue Jan 24 2017
.SHORT TERM...(Today through Wednesday)
Issued at 418 AM CST Tue Jan 24 2017
Flurries will quickly taper off this morning as mid-level cyclonic
flow moves off to the north and east and the atmospheric profile
dries out in the low levels. Most of the day today looks to be quiet
as some subtle mid-level ridging and negative vorticity develops at
the 500 mb level. There may also be some lingering patchy fog this
morning before lifting. The 24.00z GFS/NAM model soundings are
showing a somewhat dry atmospheric profile, especially from Duluth,
and points northward to the Iron Range and MN Arrowhead region, so
there could be some peeks of sun before filling back in tonight.
The big story for the short-term fcst is a quick-shot for some snow
for NW Wisconsin and adjacent counties in Minnesota Tuesday night
through Wednesday morning. This is associated with a potent mid-
level shortwave developing out of the Intermountain West states. The
forecast has changed quite a bit in 24 hours as the previous
forecast discussion mentioned. The day-shift guidance indicated a
slower progression of this system, and the 24.00z guidance has
slowed it down even further, with chances of precipitation entering
NW Wisconsin counties not until late tonight. Additionally, the
better lift that was present in the guidance from yesterday
morning`s fcst package has now shifted a bit to the south, leading
to less in the way of snowfall. This is supported by both the GEFS
and SREF snowfall ensemble plumes. Locations in NW Wisconsin may see
1 to 3" of snow accumulations, with little to no accumulation across
the Arrowhead and adjacent Minnesota counties. There could be a
brief period of rain/snow mix across NW Wisconsin Wednesday
afternoon. The brunt of this winter storm looks to affect the
southern S. Dakota/northern NE/southern MN/northern IA region
Tuesday and Wednesday, where Winter Storm Warnings are in effect.
Be sure to check the forecasts if traveling to these areas.
Some cold air advection on the backside of the system will lead to
colder temperatures beginning Wednesday and continuing through the
rest of the week. Highs Wednesday will be in the upper 20s to
.LONG TERM...(Wednesday night through Monday)
Issued at 252 AM CST Tue Jan 24 2017
As low pressure continues to move northeast Wednesday night, the
flow will become northerly from the surface on up into the upper
levels. This will allow colder air to move into the region but high
temperatures are still expected to be above normal through much of
the period. This northerly flow will send a couple shortwaves
through the region, keeping a chance for light snow or flurries
going across most of the Northland into Thursday. There will be
some lake effect snow showers along portions of the south shore of
Lake Superior into Thursday as well but by the time the more
favorable low level lapse rates develop, the flow will have backed
to more northwest. Some additional snowfall will be possible but
amounts Wednesday night and Thursday will be on the light side.
Highs Thursday will cool to the mid twenties to around thirty.
The pattern will not change much into the weekend with northerly
flow aloft sending several more shortwaves through the region with
periods of light snow or flurries across parts of the Northland.
Snow amounts will be light each day. There will be periodic chances
for heavier lake effect snow along the snowbelt regions of the south
shore of Lake Superior with the low level flow varying between west-
northwest and north-northwest as the shortwaves move through.
Accumulating snowfall will occur at times as winds go to more
northerly and the best chance for that will be late Friday night
Highs will be in the lower to mid twenties Friday and Saturday then
cool a bit more Sunday with highs in the teens to lower twenties.
.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
Issued at 1133 PM CST Mon Jan 23 2017
Widespread MVFR conditions to slowly deteriorate, and may fall
into IFR or even LIFR conditions between 09z and 15z before
improving again to MVFR or better. A few holes may develop in the
overcast with ceilings improving to VFR or better for an hour or
two through approximately 22z, with little persistence in the VFR
conditions. A storm system affecting central and southern
Minnesota and Wisconsin will spread some light snow into
KDLH, KBRD, and KHYR after 22z, keeping ceilings MVFR. Lower
ceilings and visibilities possible after 06z tonight.
.PRELIMINARY POINT TEMPS/POPS...
DLH 33 24 31 22 / 10 20 30 20
INL 30 20 29 19 / 0 10 20 50
BRD 33 25 29 19 / 10 20 30 10
HYR 37 29 34 24 / 10 40 50 30
ASX 37 29 35 26 / 10 40 40 40