Winter Storm Watch 4, NWS Sioux Falls, SD

810 
WWUS43 KFSD 110421
WSWFSD

URGENT - WINTER WEATHER MESSAGE
National Weather Service Sioux Falls SD
1021 PM CST Fri Mar 10 2017

MNZ071-072-080-081-090-111230-
/O.CON.KFSD.WS.A.0004.170312T1200Z-170313T1800Z/
Lincoln MN-Lyon MN-Murray-Cottonwood-Jackson-
1021 PM CST Fri Mar 10 2017

...WINTER STORM WATCH REMAINS IN EFFECT FROM SUNDAY MORNING
THROUGH MONDAY AFTERNOON...

* TIMING...Snow will spread across the region Sunday morning, 
  becoming moderate to heavy at times through Sunday night. 
  Light snow is expected to persist through Monday morning. 

* ACCUMULATIONS...6 to 8 inches of snow is possible.

* WIND AND VISIBILITY...Southeast winds will average 15 to 30 
  mph on Sunday, then turn northerly Sunday night and Monday. 
  The combination of gusty winds and falling snow will reduce 
  visibility as low as a half mile at times. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Watch means there is a potential for significant
snow...sleet...or ice accumulations that may impact travel.
Continue to monitor the latest forecasts.

&&

$$

374 
WWUS43 KFSD 110844
WSWFSD

URGENT - WINTER WEATHER MESSAGE
National Weather Service Sioux Falls SD
244 AM CST Sat Mar 11 2017

MNZ071-072-080-081-090-111645-
/O.CON.KFSD.WS.A.0004.170312T1200Z-170313T1800Z/
Lincoln MN-Lyon MN-Murray-Cottonwood-Jackson-
244 AM CST Sat Mar 11 2017

...WINTER STORM WATCH REMAINS IN EFFECT FROM SUNDAY MORNING
THROUGH MONDAY AFTERNOON...

* TIMING...Snow will spread across the region Sunday morning, 
  becoming moderate to heavy at times through Sunday night. 
  Light snow is expected to persist through Monday morning. 

* ACCUMULATIONS...6 to 8 inches of snow is possible.

* WIND AND VISIBILITY...Southeast winds will average 15 to 30 
  mph on Sunday, then turn northerly Sunday night and Monday. 
  The combination of gusty winds and falling snow will reduce 
  visibility as low as a half mile at times. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Watch means there is a potential for significant
snow...sleet...or ice accumulations that may impact travel.
Continue to monitor the latest forecasts.

&&

$$

673 
WWUS43 KFSD 111602
WSWFSD

URGENT - WINTER WEATHER MESSAGE
National Weather Service Sioux Falls SD
1002 AM CST Sat Mar 11 2017

MNZ071-072-080-081-090-120015-
/O.CON.KFSD.WS.A.0004.170312T1200Z-170313T1800Z/
Lincoln MN-Lyon MN-Murray-Cottonwood-Jackson-
1002 AM CST Sat Mar 11 2017

...WINTER STORM WATCH REMAINS IN EFFECT FROM SUNDAY MORNING
THROUGH MONDAY AFTERNOON...

* TIMING...Snow will spread across the region Sunday morning,
  becoming moderate to heavy at times Sunday afternoon into 
Sunday night. Light snow is expected to persist through Monday 
morning.


* ACCUMULATIONS...6 to 8 inches of snow is possible.

* WIND AND VISIBILITY...Southeast winds will average 15 to 30 
  mph on Sunday, then turn northerly Sunday night and Monday. 
  The combination of gusty winds and falling snow will reduce 
  visibility as low as a half mile at times. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Watch means there is a potential for significant
snow...sleet...or ice accumulations that may impact travel.
Continue to monitor the latest forecasts.

&&

$$

731 
WWUS43 KFSD 112112
WSWFSD

URGENT - WINTER WEATHER MESSAGE
National Weather Service Sioux Falls SD
312 PM CST Sat Mar 11 2017

MNZ071-072-080-081-090-120515-
/O.UPG.KFSD.WS.A.0004.170312T1200Z-170313T1800Z/
/O.NEW.KFSD.WS.W.0004.170312T1500Z-170313T1200Z/
Lincoln MN-Lyon MN-Murray-Cottonwood-Jackson-
312 PM CST Sat Mar 11 2017

...WINTER STORM WARNING IN EFFECT FROM 10 AM SUNDAY TO 7 AM CDT
MONDAY...

The National Weather Service in Sioux Falls has issued a Winter
Storm Warning for heavy snow and blowing snow, which is in effect
from 10 AM Sunday to 7 AM CDT Monday. The Winter Storm Watch is 
no longer in effect.

* TIMING...Snow will spread across the region Sunday morning,
  becoming moderate to heavy at times Sunday afternoon into Sunday
  night. Light snow is expected to persist through Monday morning
  and some blowing snow will also be possible.

* ACCUMULATIONS...6 to 9 inches of snow is possible.

* WIND AND VISIBILITY...Southeast winds will average 15 to 30 
  mph on Sunday, then turn northerly Sunday night and Monday. 
  The combination of gusty winds and falling snow will reduce 
  visibility as low as a half mile at times. 

* WIND CHILL VALUES...Wind chill values will fall to around zero
  late Sunday night into early Monday morning.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for heavy snow and blowing snow means
severe winter weather conditions are expected or occurring. 
Significant amounts of snow are forecast that will make travel
dangerous...and visibilities will be limited further due to strong
winds blowing snow around.  Only travel in an emergency.  If you
must travel...keep an extra flashlight...food...and water in your
vehicle in case of an emergency.

&&

$$

MNZ089-097-098-SDZ038>040-054>056-062-120515-
/O.NEW.KFSD.WW.Y.0007.170312T1200Z-170313T0900Z/
Nobles-Pipestone-Rock-Beadle-Kingsbury-Brookings-Miner-Lake-Moody-
Minnehaha-
312 PM CST Sat Mar 11 2017

...WINTER WEATHER ADVISORY IN EFFECT FROM 7 AM SUNDAY TO 4 AM CDT
MONDAY...

The National Weather Service in Sioux Falls has issued a Winter
Weather Advisory for snow and blowing snow, which is in effect 
from 7 AM Sunday to 4 AM CDT Monday. 

* TIMING...Snow will develop on Sunday morning and continue
  through Sunday night.

* ACCUMULATIONS...Snow accumulation of 3 to 6 inches will be
  possible. 6 to 9 inches of snow is possible across parts of
  southwest Minnesota so if the storm tracks just 20 to 30 miles 
farther south amounts could quickly increase.

* WIND AND VISIBILITY...Southeast winds of 15 to 25 mph will turn 
  to the north with gusts of 30 to 35 mph possible Sunday night.

* WIND CHILL VALUES...Wind chill values will fall to around zero
  late Sunday night into early Monday morning.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for snow and blowing snow means that 
visibilities will be limited due to a combination of falling and 
blowing snow. Use caution when traveling...especially in open 
areas.

&&

$$

IAZ001>003-012>014-021-022-120515-
/O.NEW.KFSD.WW.Y.0007.170312T1500Z-170313T1200Z/
Lyon IA-Osceola-Dickinson-Sioux-O'Brien-Clay IA-Cherokee-
Buena Vista-
312 PM CST Sat Mar 11 2017

...WINTER WEATHER ADVISORY IN EFFECT FROM 10 AM SUNDAY TO 7 AM
CDT MONDAY...

The National Weather Service in Sioux Falls has issued a Winter
Weather Advisory for snow and blowing snow, which is in effect 
from 10 AM Sunday to 7 AM CDT Monday. 

* TIMING...Snow will develop late Sunday morning and continue 
  through Sunday night.

* ACCUMULATIONS...Snow accumulation of 3 to 6 inches will be
  possible. 6 to 9 inches of snow is possible across parts of
  southwest Minnesota so if the storm tracks just 20 to 30 miles 
  farther south amounts could quickly increase.

* WIND AND VISIBILITY...Southeast winds of 15 to 25 mph will turn 
  to the north with gusts of 30 to 35 mph possible Sunday night.

* WIND CHILL VALUES...Wind chill values will fall to around 5
  above zero late Sunday night into early Monday morning.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for snow and blowing snow means that 
visibilities will be limited due to a combination of falling and 
blowing snow. Use caution when traveling...especially in open 
areas.

&&

$$

Area Forecast Discussion
National Weather Service Sioux Falls SD
311 PM CST Fri Mar 10 2017

.SHORT TERM...(This evening through Saturday)
Issued at 311 PM CST Fri Mar 10 2017

Thus far low level dry air is winning out over the weak to moderate
forcing along the mid level dendritic layer. Multiple weak bands of
evaporating precipitation have been occurring through the day but
snow has yet to fall anywhere. Suspect that by mid to late afternoon
some of this snow will begin to reach the ground but should remain
light. Dew points at the surface have been falling through the day
across southwest MN and eastern SD so still a challenge in the low
levels to get the snow to the surface.

Went ahead and decreased amounts across the area as the latest
trends in the models suggest that if snow can get going it will be
across southern parts of central SD into northern Nebraska. This
makes sense given the challenging dry low levels as the air is a bit
less dry in these locations. Also noted was the the snowfall in
western SD is collocated with the right entrance region of the upper
level jet and close to the 900-800mb boundary. If trends on movement
of the jet and boundary occur as expected, the snowfall in western
SD will develop southeast towards south central SD late this
afternoon into the evening. So overall radar trends will see drying
on the north side of the band and new development on the south side.

Overall this is a fairly poorly forced event and is struggling with
moisture. So if we do see a spot with a threat for 2-3 inches of
snow it will be along and west of the James River Valley.

A tough call on Saturday snowfall chances with lower confidence on
this afternoon and tonights snowfall. Models do indicate a deeper
dendritic layer and occasional saturation within this layer. Also
some hints of weak instability in the mixed layer which may support
some instability snow showers as well. Regardless, not anticipating
a lot in the way of accumulation.

.LONG TERM...(Saturday night through Friday)
Issued at 311 PM CST Fri Mar 10 2017

The focus on the medium range into the extended are the series of
waves that are expected to impact the region on Sunday into Monday.
Precipitation event begins with a series of waves dropping from the
Pacific NW into the Northern Plains.  Precipitation is expected to
develop Sunday morning as strong isentropic ascent is expected to
develop in an area of warm air advection.  Also have some 700 mb
frontogenetic forcing that develops but scoots out of the area in
the afternoon hours.  The biggest changes in this forecast package
is the trajectory of the kicker wave that appears to be focused
slightly further east than previous runs would suggests.  This
shifts the heaviest snow Sunday into Sunday night across our far
eastern portions of our forecast area. Still expecting some
interaction with the left exit region of the jet streak working into
the region Sunday night into Monday morning.

Have heaviest snowfall along and east of the Buffalo Ridge.  With
coordination from surrounding offices, have elected to issue a
winter storm watch for small portion of SW Minnesota where snow and
blowing snow may be an issue.

Monday into Tuesday look to remain below freezing, but with less
snowfall anticipated and temperatures aloft moderating some, don't
have forecast temperatures as cold as yesterday.  Appears as though
there is a fairly sizable warm up late in the week.  With snow being
relatively dry, it may melt relatively quickly leading to
potentially warmer temperatures than are currently advertised by
Friday. Did not alter temperatures beyond Monday, as the emphasis
was on the storm system.

&&

.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
Issued at 1120 AM CST Fri Mar 10 2017

Light snow will gradually overspread the area this afternoon and
tonight but at this time most locations should remain MVFR. Some
IFR ceilings will be possible and a few of the snow bands could
briefly reduce the visibility to a mile or so. The light snow will
continue into Saturday morning.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...Winter Storm Watch from Sunday morning through Monday afternoon
     for MNZ071-072-080-081-090.

IA...None.
NE...None.
&&

SHORT TERM...08
LONG TERM...BT
AVIATION...08

Hazardous Weather Outlook
National Weather Service Sioux Falls SD
330 AM CST Fri Mar 10 2017

IAZ001>003-012>014-020>022-031-032-MNZ071-072-080-081-089-090-097-
098-NEZ013-014-SDZ038>040-050-052>071-110930-
Lyon IA-Osceola-Dickinson-Sioux-O'Brien-Clay IA-Plymouth-Cherokee-
Buena Vista-Woodbury-Ida-Lincoln MN-Lyon MN-Murray-Cottonwood-
Nobles-Jackson-Pipestone-Rock-Dixon-Dakota-Beadle-Kingsbury-
Brookings-Gregory-Jerauld-Sanborn-Miner-Lake-Moody-Brule-Aurora-
Davison-Hanson-McCook-Minnehaha-Charles Mix-Douglas-Hutchinson-
Turner-Lincoln SD-Bon Homme-Yankton-Clay SD-Union-
330 AM CST Fri Mar 10 2017

This Hazardous Weather Outlook is for portions of northwest Iowa,
west central Iowa, southwest Minnesota, northeast Nebraska,
central South Dakota, east central South Dakota, south central
South Dakota, and southeast South Dakota.

.DAY ONE...Today and Tonight

Light snow will develop in areas west of Interstate 29 today, then
spread eastward tonight. Snowfall totals by Saturday morning will
range from around 3 to 4 inches through the James River Valley
into the mid Missouri River Valley, with amounts of 1 to 2 inches
elsewhere across the area.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday

Light snow will continue into Saturday afternoon, with additional
accumulation of around an inch possible.

A more potent system will affect the area on Sunday and Sunday
night. Snowfall totals of 4 to 6 inches will be possible from east
central South Dakota, through southwestern Minnesota, into
northwestern Iowa, tapering down to near 1 inch over south central
South Dakota. Winds will also increase on Sunday which could
produce areas of blowing and drifting snow.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed.