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FXUS63 KMPX 200006

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
606 PM CST Fri Jan 19 2018

.SHORT TERM...(This evening through Saturday)
Issued at 310 PM CST Fri Jan 19 2018

Little in the way in short term concerns. Still will see a fair
amount of high clouds streaming in from the west/southwest. If
clouds thin long enough overnight, we may have to introduce at
least some patchy fog over the cwa later tonight. Had another fair
amount of melting again today and it is the second day. We should
have abundant enough low level moisture to at least think about
some patchy fog in mainly clear areas. Looking for more clouds
again Saturday and this will limit heating some. However, we may
be too cool again if sunshine is more abundant. 

.LONG TERM...(Saturday night through Friday)
Issued at 310 PM CST Fri Jan 19 2018

Main concern in the longer term remains the headline/winter storm
potential Sunday night and Monday. 

The 12z GFS and GEM have come in with little in the way of 
shifting the resultant snow band from the 00Z runs. The 12z ECMWF
did drop a bit farther south however. There will likely still be
some shifting in the overall snow band as the trough is just now 
coming onto the southwest coast. QPF has been lessened to the 
northwest and still ranging from one half inch to near an inch in
the heavier winter storm watch area.

The heavier period of snow still looks to be 12z-18z Monday with
the morning commute affected. Snowfall rates could range around an
inch an hour during this period. This shifts east by Tuesday
evening and we did extend the watch into Tuesday evening farther
to the east. We also added the remainder of he southern counties
to the watch with a couple of counties to the northwest. Blowing
and drifting will be an issue especially along the Minnesota River
Valley Monday. We will likely see wind gusts to 35 mph with
considerable blowing and drifting snow. The southwest will have 
to be monitored for possible blizzard conditions if winds end up 

Cooler temperatures will ensue following the storm- closer to
normal readings. The overall upper flow pattern returns to ridging
over the central CONUS toward the end of the week. THis should 
warm temperatures above normal again through the end of the week.


.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 538 PM CST Fri Jan 19 2018

The main concern for this TAF period is the chance for fog
Saturday morning. High cloud cover will continue overnight with 
cloud cover becoming more scattered in nature at times. Moisture 
from the recently melted snow and light winds under 5 kts 
overnight will likely result in patchy fog. Thus, MVFR conditions
are possible between 10 and 15Z over much of Central MN and 
northwestern WI. Otherwise, cloud ceiling heights will decrease to
near 10,000 ft Sunday ahead of the upcoming winter storm system. 
Winds in West Central WI are expected to shift to the W/WNW 
tonight and then winds across the forecast area will remain light 
and predominately out of the W/WNW through Saturday afternoon. 

KMSP... Patchy fog is possible from 10 to 15Z Saturday. VFR 
conditions are forecast but a downgrade to MVFR may be needed 
should future guidance indicate lower visibilities. 

Sun... VFR early, MVFR or lower with -SN or wintry mix likely 
Sunday afternoon. IFR or lower with snow late Sunday night. Wind 
NE 5-15 kts. 
Mon...IFR or lower most of the day with SN/BLSN. Wind N 15-25 kts
gusting to 30 kts. 
Tue...VFR with MVFR possible. Wind NW at 10-15 kts.


WI...Winter Storm Watch from Sunday evening through Monday evening 
     for WIZ014>016-023>028.

MN...Winter Storm Watch from Sunday evening through Monday afternoon 
     for MNZ053-060>063-065>070-073>077-082>085-091>093.

     Winter Storm Watch from Sunday evening through Monday evening 
     for MNZ078.


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