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Office: MPX

FXUS63 KMPX 171122

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
622 AM CDT Sat Mar 17 2018

Issued at 520 AM CDT Sat Mar 17 2018

Updated to include 12z aviation discussion below.


.SHORT TERM...(Today and tonight)
Issued at 500 AM CDT Sat Mar 17 2018

Surface analysis early this morning shows broad high pressure over
the Dakotas into MN/WI while a potent low pressure center is
located over central MO. Aloft, an upper level low is situated
atop the surface low while a ridge of high pressure sits to the
north, spread across the Dakotas into MN. The ridge over this
region will be reinforced by a ridge axis extending from the Deep
South into the Central Plains and this ridge will then poke north
into the Northern Plains. This building ridge will help squeeze
the low pressure system to the south away to the east, ending
precipitation over southern MN by around daybreak this morning and
allowing skies to gradually clear out across the Upper
Mississippi River Valley region today. As the ridge axis moves
across the region, the center of high pressure will slide
southeast, moving into the Ohio River Valley region by daybreak
Sunday morning. A swath of mid-upper level moisture on the
backside of the ridge will spell an increase in higher clouds this
evening through overnight tonight but no precipitation is
expected. Warmer temperatures are expected for today with the deep
high pressure and clearing skies. Highs will range through the
40s across the WFO MPX coverage area followed by lows tonight in
the 20s area-wide.

.LONG TERM...(Sunday through Friday)
Issued at 500 AM CDT Sat Mar 17 2018

The main longer term concerns remain the snow chances late Monday
into Tuesday night and again late in the week.

Sunday still looks mild with some clouds still forecast to move
eastward during the day. Latest model trends they may not work
into western WI during the day. If this holds true, that region
should remain the warmest. We kept the lower and middle 40s for

The timing of the next trough brings moisture and weak forcing
into far western Minnesota late Monday. This spreads east Monday
night through Tuesday night at least. The trough weakens as it
moves through. Moisture/forcing weakens Tuesday so at the moment,
it appears any snow chances wont make it far into west central
Wisconsin. Forecast snow totals range less than 2 inches with
this system. This could change of course, depending on the
strength of the incoming trough and if it taps deeper moisture.

The Canadian and ECMWF were indicating a secondary trough moving
through the northern stream Wednesday. Small PoPs were indicated
with the blended model with this system. If the trends of the
ECWMF and Canadian models continue, we may have to increase
chances for Wednesday as well. Again, it looks like it mainly
affects the MN portion of the cwa.

Finally, the next and potentially more significant system arrives
later Thursday night and Friday as more western CONUS trough
energy moves into the region. This system looks rather warm as it
moves into the area Friday with mainly rain indicated at this time
with a rather warm boundary layer. This system will have to be
monitored for the potential of more significant weather into the


.AVIATION...(For the 12Z TAFS through 12Z Sunday morning)
Issued at 520 AM CDT Sat Mar 17 2018

High pressure will slide across the region today, allowing for
light/variable winds and mainly clear skies. As the high pressure
moves off to the east tonight through tomorrow, clouds will return
to western MN, creating upper level ceilings which will gradually
lower. By midday tomorrow, MVFR ceilings would not be
unreasonable, especially for the MN TAF sites. No precipitation
nor any visibility restrictions expected.

KMSP...No weather concerns through tonight, then ceilings are
likely to develop after daybreak. At this point, have kept
ceilings within VFR range but having MVFR ceilings around 18z or
shortly thereafter tomorrow cannot be ruled out.

MON...MVFR cigs likely. Wind ENE 10 kts.
TUE...MVFR cigs likely. Chc -RA/-SN. Wind E 5 kts.
WED...Mainly VFR. MVFR cigs possible. Wind E 5 kts.





Office: DLH FXUS63 KDLH 171139 AFDDLH Area Forecast Discussion National Weather Service Duluth MN 639 AM CDT Sat Mar 17 2018 .SHORT TERM...(Today through Sunday) Issued at 207 AM CDT Sat Mar 17 2018 Dry conditions continue across the Northland today and tonight. Another day of abundant sunshine is anticipated today as surface high pressure currently situated over northeast North Dakota at 07z this morning is progged to translate southeastward through the day. Didn't deviate much from the previous forecast package in regard to the high temperatures today, with highs still expected to rise into the middle 40s to lower 50s across the area. For these highs, leaned heavily towards the bias-corrected raw model blends, which seems to have had a good handle on the high temperatures lately. Also, decreased the minimum relative humidity values up to 5 percent due to the abundant sunshine and warm, dry return flow around the surface high. Clouds will slowly increase, especially across north-central Minnesota and over the tip of the Minnesota Arrowhead early Sunday morning as a surface low pressure system passes by to our northeast this evening, bringing better moisture with it. No precipitation is expected from the passage of this low as NAM/GFS soundings indicate too much dry air near the surface for anything to materialize, but cloud cover should increase through the day Sunday as colder air seeps into the region once the low passes through. 925 mb temperatures could drop to between 5 to 10 degrees C below zero over adjacent areas of Lake Superior, with nearly 0 degrees C elsewhere. Temperatures Sunday should still be above seasonal normals, but will be cooler compared to today's temperatures, with highs in the upper 30s to lower 40s. .LONG TERM...(Sunday night through Friday) Issued at 207 AM CDT Sat Mar 17 2018 The extended period remains relatively quiet with few significant weather makers moving through/near the Northland. Temperatures will be a couple degrees either side of normal, starting off cooler then moderating slightly Thursday and Friday. A surface low pressure system will be centered along the Colorado/Kansas border Sunday evening with an inverted trough extending well north into the Northern Plains. An area of high pressure will extend from northern Manitoba to Lake Superior at the same time. The low and inverted trough will move east Sunday night into Tuesday with the inverted trough weakening over that time. A northern stream shortwave will also move into the region Tuesday into Wednesday. The low level winds will become easterly Sunday night and continue through much of the week. Most of the Northland will remain dry Sunday night into Monday but some light lake effect snow showers or flurries will be possible over western Lake Superior through at least mid week. Plenty of dry air will be in place over eastern Lake Superior which should keep significant lake effect snow in check despite the long fetch and upstream 850MB temperatures supportive for lake effect snow. Light snow will be possible over other portions of the area Monday night through Tuesday night but little accumulation is expected at this time. Little or no precipitation is expected outside of lake effect snow showers around Lake Superior from mid through late week as an upper ridge builds and then moves over the region through that time. && .AVIATION...(For the 12Z TAFS through 12Z Sunday morning) Issued at 639 AM CDT Sat Mar 17 2018 High pressure over the region today will move east and south tonight into Sunday. An inverted trough will move into the Northern Plains tonight into Sunday. Mostly clear skies will occur for most areas today and tonight with more clouds expected on Sunday. Conditions will remain VFR through the period as mainly mid and high clouds are expected Sunday. Winds will be less than 10 knots for most areas. && .PRELIMINARY POINT TEMPS/POPS... DLH 50 24 39 18 / 0 0 10 10 INL 50 17 40 15 / 0 0 10 10 BRD 47 19 43 21 / 0 0 10 10 HYR 49 18 44 20 / 0 0 0 10 ASX 48 24 39 17 / 0 0 10 10 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. LS...None. && $$ SHORT TERM...JTS LONG TERM...Melde AVIATION...Melde