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fxus63 kfsd 221634 

Area forecast discussion
National Weather Service Sioux Falls South Dakota
1034 am CST Fri Nov 22 2019

Short term...(today and tonight)
issued at 334 am CST Fri Nov 22 2019

Dry weather conditions and plenty of sunshine are expected today as
the surface high pressure to our south continues to shift eastward.
Surface winds will transition to south through the day, bringing
near seasonal temperatures. Highs will range from the mid 30s to
upper 40s.

An upper-level wave over The Rockies will move through the Central
Plains today, approaching our forecast area tonight. Minimal, if any
impacts are expected in our area, with only high-level clouds
filtering in. To our north, a shortwave will move through ND/Minnesota,
dragging a weak cold front through the region. Precipitation is not
anticipated; however, a gradual wind shift to the west is expected.
This will result in a mild night. Have increased lows around the
50th percentile to produce temperatures in the mid-upper 20s.

Long term...(saturday through thursday)
issued at 334 am CST Fri Nov 22 2019

The weak cold front passes through the region on Saturday bringing
breezy conditions, mainly west of I-29. Northwest flow aloft will
keep the region dry and mild with highs mainly in the 40s. Flow
aloft shifts to a more zonal component on Sunday, leading to even
warmer conditions. In fact, 850 mb temperatures warm to 4-7 degrees
celsius, which can potentially bring highs from the upper 40s to mid
50s. Several disturbances move through the region Sunday through
Monday. However, low to mid level moisture is limited, thus little
if any precipitation is expected.

Attention then turns to the next upper-level trough system crossing
The Rockies on Monday night, then moving over the Central Plains on
Tuesday. Most of the deterministic models continue to differ in
strength and bring the bulk of precipitation south of the forecast
area. On the other hand, the European model (ecmwf) and ensemble solutions bring
precipitation to our region, mainly south of I-90. Have kept a low-
end chance for rain/snow mainly on Tuesday, with better focus south
of I-90.

Ridge aloft builds in on Wednesday, keeping the region relatively
dry. Precipitation chances increase from Thanksgiving into the
weekend ahead of a strong upper low developing over the Pacific
northwest. There is a lot of uncertainty for this period, with
different solutions/timing/track; therefore confidence/detail
remains very low/uncertain.


Aviation...(for the 18z tafs through 18z Saturday afternoon)
issued at 1031 am CST Fri Nov 22 2019

VFR conditions expected through the taf period. Light
south/southwesterly winds will transition to west/northwesterly by
Saturday morning.


Fsd watches/warnings/advisories...
South Dakota...none.


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