Area Forecast Discussion


626 
FXUS63 KDLH 250930
AFDDLH
Area Forecast Discussion
National Weather Service Duluth MN
330 AM CST Sun Feb 25 2018
.SHORT TERM...(Today through Monday)
Issued at 330 AM CST Sun Feb 25 2018
The latest winter storm to affect the Northland will wind down 
this morning for most locales with light snow showers or flurries 
lingering into this afternoon.
Light to moderate snow continued across the Northland early this 
morning. A compact but deep shortwave trough stretched from 
northwest Ontario southeastward toward southern Lake Michigan. A 
secondary shortwave with a compact ribbon of vorticity was found 
farther west from central Manitoba south into the Red River 
Valley. The latest MSAS surface analysis indicates the center of a
994 mb low over western Upper Michigan with a secondary center 
over northern Lake Michigan. An inverted trough extended to the 
northwest over northern Minnesota and into southeast Manitoba. The
storm system will continue its fast east-northeastward trajectory
into northeast Ontario by noon today. The secondary shortwave 
aloft is forecast to rotate eastward across our northern zones 
during the day. The bulk of the snow with the surface low will 
taper off this morning from southwest to northeast. The secondary 
trough, overall cyclonic flow, and cold air advection should be 
able to wring out some lingering snow showers and flurries through
this afternoon. Have held onto some low chance POPs and flurries 
to the forecast with this update.
Have adjusted the end times of the current suite of headlines. 
Snow has all but ended from Cass and S. Itasca through Pine 
County, so have cancelled the Winter Storm Warnings for those 
locales. The next tier of zones from S. St. Louis/Carlton south to
Price County will end at 12Z and everything else is slated to go 
at 15Z. Given the speed with which snow is tapering off to light 
snow showers and flurries, earlier expiration times seemed 
appropriate. Still think light snow showers and flurries will 
continue this morning into the afternoon, but additional 
accumulation from those contributions will be negligible.
Another fast-moving clipper will advance eastward across the 
Canadian Prairies and into northwest Ontario tonight and Monday. 
The clipper will back winds from westerly to southwesterly keeping
temperatures elevated tonight and trending warmer for Monday. The
southerly flow aloft and warm air advection should yield 
additional cloud cover over northern Minnesota tomorrow. Think we 
may see some snow showers or flurries along the International 
Border, but kept POPs below 15% for this update cycle. The ECMWF 
is the only deterministic model which brings QPF near the 
Northland, so while POPs were increased above the consensus blend,
still opted for a dry forecast. Highs will reach the upper 30s to
near 40 for most locales.
.LONG TERM...(Monday night through Saturday)
Issued at 330 AM CST Sun Feb 25 2018
The early part of the week will see the upper air pattern to be 
in a split flow regime with the Northland mainly out of the 
general path of either the northern branch or southern branch. 
This also puts the Northland in a nearly Pacific flow which will 
bring a milder period with above normal temperatures by 5 to 10 
degrees. The next chance for any precipitation will be Thursday 
when the northern stream merges with the southern stream and 
brings the upper trough through the region. At this point the 
resultant lee cyclone will be moving up through the mid 
Mississippi Valley then into Ohio. That will put mainly the 
southern portion of our forecast area in any precipitation 
chances, with the northern extent into the Twin Ports. A stronger 
trough will dig into the southwest U. S. next weekend, bringing a 
chance of precipitation for later next weekend.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1130 PM CST Sat Feb 24 2018
An upper level trof was moving over the terminals at the start of
the forecast. This resulted in light to moderate snow affecting
all locations, accompanied by IFR/LIFR cigs and vsbys. As the trof
moves east of the terminals after 12Z, the snow will end from
southwest to northeast through the morning. Cigs and vsbys will 
improve to MVFR, with scattered VFR. Gusty surface winds are 
expected to affect the terminals from mid morning through the 
afternoon, diminishing around sunset. 
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH  29  14  36  19 /  30  10   0   0 
INL  28  14  39  16 / 100  20  10   0 
BRD  29  13  36  16 /  20   0   0   0 
HYR  29  15  39  20 /  20  10   0   0 
ASX  31  19  39  24 /  40  10   0   0 
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...Winter Storm Warning until 6 AM CST early this morning for 
     WIZ001-006>009.
     Winter Storm Warning until 9 AM CST this morning for WIZ002>004.
MN...Winter Storm Warning until 6 AM CST early this morning for 
     MNZ037.
     Winter Weather Advisory until 9 AM CST this morning for MNZ010-
     018.
     Winter Storm Warning until 9 AM CST this morning for MNZ011-012-
     019>021.
LS...None.
&&
$$
SHORT TERM...Huyck
LONG TERM...CLC
AVIATION...GSF