Area Forecast Discussion
Issued by NWS Sioux Falls, SD

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FXUS63 KFSD 142035

Area Forecast Discussion
National Weather Service Sioux Falls SD
335 PM CDT Sat Apr 14 2018

.SHORT TERM...(This evening through Sunday)
Issued at 317 PM CDT Sat Apr 14 2018

Significant late season blizzard continues to hold its grip on much
of our region as of mid afternoon Saturday. Very potent upper
level low is evident on WV imagery near the IA/NE/KS/MO border
with the dry slot punching as far north as just south of Sioux
City. Large scale upper level forcing is progged to continue to
weaken through the late afternoon and evening hours but lower
level frotogenetic forcing has resulted localized heavier bands,
within a broader area of snow over far eastern South Dakota, NW
Iowa and SW Minnesota. Latest guidance continues to slow the
eastward progression of the upper low, and thus have raised
evening snow chances along and east of I-29. In fact, on and off
light snow could very well continue through much of the day Sunday
east of I-29, although the bulk of the accumulating snow should
taper off around or shortly after midnight for most areas.
Wouldn`t be surprised to see a period of a bit of freezing
drizzle on the back side of the system as the ice growth zone
dries out and lower levels remain saturated. The duration at any
one location of this occurring is expected to be fairly minimal.

Due to the slower exit of the system, have extended the ending time
of the Blizzard Warning for a few hours along the I-29 corridor
and east of there until daybreak Sunday. Have also boosted snow
totals for some locations given the longer duration. Winds will
also continue to be a factor through the evening and overnight
hours. Pressure gradient remains tightly packed through the
evening, slacking slightly after midnight as the surface low
pushes into IL.

Other than occasional light snow over SW MN and NW IA and continued
breezing winds, Sunday will be overall quieter. With fresh snow
cover and 925 mb around -5 C, expect temperatures well below normal
for mid April. In fact, many locations may not rise above

.LONG TERM...(Sunday night through Saturday)
Issued at 317 PM CDT Sat Apr 14 2018

Below normal temperatures continue into next week with mainly 30s to
mid 40s for highs. Lowered high and low temperatures toward
Consraw values as the populated guidance is likely too high with
the new snowpack and influence of climatology. The next chance of
precipitation arrives into the region Tuesday night into
Wednesday. Still some disagreement in the models with the GFS
further north with the upper level wave and ECMWF further south.
With this, the GFS would be slightly warmer with less accumulating
snow, and the EC slightly cooler with more accumulating snow.
Will get through the ongoing weather hazards first before diving
into the midweek system, but certainly will be a period to keep an
eye on. Yet another significant wave pushes into the central US
by next weekend but is much too far out there to get into any
details as far as precipitation types or potential impacts.


.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1237 PM CDT Sat Apr 14 2018

Very poor conditions expected through the day and into this
evening, with snow and blowing snow due to frequent wind gusts in
excess of 35-40kt. Gradual improvement this afternoon toward the
James River Valley, and after 00Z-03Z along I-29. IFR conditions
will likely persist into Sunday morning for parts of southwest
Minnesota, with MVFR ceilings dominant elsewhere around the area.


SD...Blizzard Warning until 1 AM CDT Sunday for SDZ040-056-062-067-

     Blizzard Warning until 7 PM CDT this evening for SDZ038-050-052-

     Blizzard Warning until 10 PM CDT this evening for SDZ039-054-055-

MN...Blizzard Warning until 1 AM CDT Sunday for MNZ098.

     Blizzard Warning until 7 AM CDT Sunday for MNZ071-072-080-081-

IA...Blizzard Warning until 1 AM CDT Sunday for IAZ001-012-020-031.

     Blizzard Warning until 7 AM CDT Sunday for IAZ002-003-013-014-

NE...Blizzard Warning until 1 AM CDT Sunday for NEZ013-014.



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