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000 
FXUS63 KMPX 221711
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
1111 AM CST Mon Jan 22 2018

.SHORT TERM...(Today and tonight)
Issued at 451 AM CST Mon Jan 22 2018

The winter storm remains on track for southern Minnesota and western 
Wisconsin.  The hazards that were in place yesterday were left 
untouched as the adjustments were mainly focused on tweaking the 
northern gradient and adjusting the thermal profile from the Albert 
Lea toward Eau Claire areas.

Early this morning, the deepening surface low was located over 
extreme northwestern Missouri and will continue to deep and lift 
into Iowa today.  Meanwhile, the main precipitation band is taking 
shape from Nebraska through northern Iowa, and is lifting into 
southern MN.  Albert Lea continues to report rain falling, but to 
the east a cooler thermal profile has allowed a changeover to snow 
to occur.  

The hi-res models now cover the storm as it moves through and has 
only increased our confidence in the forecast.  The heaviest band of 
snow of 8-14" remains in the same place; from near Fairmont through 
Red Wing, Menomonie, and Ladysmith.  

The Twin Cities metro still looks to have a tight snowfall gradient. 
With the RAP, HRRR, and HOPWRF now covering the temporal period of 
the storm, confidence is increasing that the southeast metro will 
see 6"+ of snow and the gradient may be a few miles northwest of 
earlier expectations.  Did adjust the snow amounts upward along the 
northern gradient. Further aiding in this decision was the fact that 
overnight lightning across the state of Iowa wasn't all that 
widespread.  In addition, we've been watching a west to east band of 
snow developing from Canby through the metro toward Menomonie.  This 
will produce some light snowfall this morning before the main event 
ensues for the metro mid morning, with the heaviest snow expected 
this afternoon.

The HRRR and RAP show the potential for a heavy snow band to impact 
the metro mid afternoon leading up to the evening commute.  This 
band could have 1-2"/hr rates given the strong mesoscale forcing 
associated with it and make for a very slow commute this evening.

The winds will continue to strengthen as the low moves through Iowa 
today, with blizzard conditions developing from south and west of 
Mankato. Again, the heaviest snow will arrive in far southern MN 
early this morning, with the heaviest period of snow expected later 
today in the metro and western WI. The morning commute will be 
impacted across far southern MN by the onset of the snow, while the 
metro and Wisconsin will see minimal issues this morning for the 
commute. The afternoon commute will be a completely different
story.

.LONG TERM...(Tuesday through Sunday)
Issued at 451 AM CST Mon Jan 22 2018

No significant changes in the extended. Blended guidance shows a 
slight cool down in the wake of today's storm, with highs in the mid 
to upper 20s Tuesday and Wednesday, but this is still about 2 to 5 
degrees above the seasonal average for late January. A weak 
shortwave will embedded in northwest flow will slide southeast 
across the region Tuesday night, and this should be strong enough to 
produce some clouds, but not enough to precipitate other than 
perhaps a few flurries.

Upper level ridging will ensue for Wednesday night and Thursday, 
keeping the region dry and mild. On Friday highs could reach the 
lower 40s across the region as the low level thermal ridge advects 
across the region. A cold front will follow Friday night with cold, 
but not bitterly cold temperatures for the weekend into early next 
week. No significant precipitation is expected at this time.

&&

.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 1110 AM CST Mon Jan 22 2018

A full scale winter storm will impact MPX taf sites from KRWF,
northeast to KRNH and southward through 00z, and possibly beyond
00z around KRNH/KMKT/KMSP. High confidence that LIFR/IFR 
cigs/vsbys in snow and blowing snow will affect 
KRWF/KMSP/MRNH/KMKT/KEAU through the afternoon, with some mixture 
of PL near KEAU after 21z. There is a chance of vsbys/cigs near
airport minimums during the height of the storm. Only KAXN will 
have IFR/MVFR cigs with no restrictions to vsby as all the 
snowfall will be southeast of this airport. KSTC will be on the 
edge after 21z, and possibly MVFR vsbys in snow between 21-03z. 
Otherwise, conditions will slowly improve between 3-6z in east 
central Minnesota, west central Wisconsin, but IFR/MVFR cigs will 
likely continue through Tuesday morning. Winds will remain from 
the northeast to north, with a more north to northwest direction 
late this afternoon/evening. Gusty winds will continue until late 
this evening. 

KMSP...

Only additional comments are snowfall rates will approach or 
exceed 1 to 1.5 inches per hour during the afternoon, and possibly
last through 00z. Confidence is high that LIFR/IFR conditions 
will remain, with vsbys as low as 1/4SM in heavy snowfall/blowing
snow. There could be a short period of cigs/vsbys near airport 
minimums during the height of this storm. Northeast winds of 
16-18 kts, gusts to 24-28 kts, with slowly become more 
north/northwest this evening/overnight and decrease in speed. 
Total snowfall through this event could exceed 12 inches before 
06z. 

/OUTLOOK FOR KMSP/

Tue...MVFR thru mrng. Winds NW 5-10 kts. 
Wed...MVFR/IFR cigs. Winds 5 kts or less. 
Thu...MVFR/IFR cigs. Winds SE 5-10 kts. 

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
WI...Winter Storm Warning until midnight CST tonight for WIZ014>016-
     023>028.

MN...Winter Storm Warning until midnight CST tonight for MNZ060-062-
     063-067>070-078.

     Winter Weather Advisory until midnight CST tonight for MNZ053-
     061-065-066-073.

     Blizzard Warning until midnight CST tonight for MNZ074>077-
     082>085-091>093.

&&

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