Sioux City, Iowa 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

201
FXUS63 KFSD 151929
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
229 PM CDT Thu May 15 2025

.KEY MESSAGES...

- Strong winds and persistent rain to rain showers are expected
  to drift back southward on Friday.

- Wind gusts over 50 mph may be possible at times through
  Friday afternoon. Wind advisories have been issued and local
  upgrades to high wind warnings possible.

- After a quiet and cool weekend, moderate to high probabilities
  of rain (90%) return Monday and Tuesday.

&&

.DISCUSSION...
Issued at 225 PM CDT Thu May 15 2025

THIS AFTERNOON:  A large upper low continues to track northeast
through the Dakotas, likely to end up in northeastern Minnesota by
Friday morning.  Persistent stratus will rotate around this trough
through the afternoon, but showers may lift northward by 00z. Enough
clearing is taking place near or south of the MO river for some
instability showers to form, which may continue into the evening.
Winds are continuing to increase this afternoon as 40 to 50 mph
winds mix down.

TONIGHT:  Lingering instability showers dissipate early this
evening. More persistent light rains may drift north of Highway 14
this evening and into the overnight hours.  Winds may also subside
south of I-90 and will allow wind advisory to expire in some
areas along and south of I-90. Moisture rotating around the
western side of the upper trough will begin to sink back
southward towards daybreak Friday, bringing showers southward
with it. More uncertain is the potential for persistent mix down
of 45 to 55 mph winds with the showers into Friday morning.
CAMS certainly suggest potential for high wind warning gusts
along the 14 corridor, but these models may also overdue strong
winds overnight.

FRIDAY:  The upper low begins to settle back southward and fill on
Friday, pushing rain chances across the CWA through the day.  Rain
amounts won`t be significant, but persistent showers may add up to a
tenth or two.  Winds however will also increase and any breaks in
the clouds will push stronger gusts downward.  Will extend a wind
advisory across the entire CWA.

SATURDAY:  Dry air gets pulled into this system Friday night into
Saturday, bringing rain to and end, but likely keeping stratus
around into Saturday morning. Lows will be quite chilly falling
into the lower 40s. Highs on Saturday afternoon are expected to
remain well below normal, only climbing into the lower to
middle 50s in most locations, and a few 60s near the Missouri
River.

SUNDAY: Mid-lvl warm advection and moisture return begins on Sunday,
pulling an increase in cloud cover and potential for light sprinkles
to showers through central South Dakota during the first half of the
day.  Elsewhere, drier easterly surface flow will keep temperatures
cool with highs in the 60s.

MONDAY-WEDNESDAY: Medium range guidance remains in strong agreement
that a large upper trough will move through the western CONUS
and begin to influence the Plains early in the week. Broad warm
advection showers and thunderstorms develop over the Central
Plains Sunday night, and will spread northward into the Mid and
upper Missouri River valley on Monday. Rainfall probabilities
remain high at nearly 90%, with 1" QPF probabilities from the
GEFS/ECMWF pushing 50% in some areas. More uncertainty develops
in regards to the track and depth of the upper low that moves
into the Plains Tuesday into Wednesday. ECMWF remains slightly
further north with the upper low than the GFS/CMC keeping a rain
chance over the entire CWA through Tuesday. Outside of some
initial elevated convection during the onset of the event,
severe weather risks remain low through the period. Temperatures
are also expected to remain near to slightly below seasonal
normals.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1219 PM CDT Thu May 15 2025

Upper low will continue to deepen and then fill across northern
Minnesota by Friday morning. The result will be MVFR ceilings
and scattered rain lifting north of the CWA later this afternoon
and evening. VFR conditions are likely in most areas, outside of
Highway 14 overnight. Gusty westerly winds will persist into the
evening, with potential for 40 to 50 mph winds at times.

The upper low pivots back south on Friday, pushing MVFR stratus
and showers southward through the Tri-State area during the
day.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...Wind Advisory until 9 PM CDT this evening for SDZ060>062-
     065>071.
     Wind Advisory from 1 AM to 7 PM CDT Friday for SDZ060>062-
     065>070.
     Wind Advisory from 7 AM to 7 PM CDT Friday for SDZ071.
     Wind Advisory until 7 PM CDT Friday for SDZ038>040-050-052>059-
     063-064.
MN...Wind Advisory until 9 PM CDT this evening for MNZ089-090-098.
     Wind Advisory from 1 AM to 7 PM CDT Friday for MNZ089-090-098.
     Wind Advisory until 7 PM CDT Friday for MNZ071-072-080-081-097.
IA...Wind Advisory until 9 PM CDT this evening for IAZ001>003-
     012>014-020>022-031-032.
     Wind Advisory from 1 AM to 7 PM CDT Friday for IAZ001-002.
     Wind Advisory from 7 AM to 7 PM CDT Friday for IAZ003-012>014-
     020>022-031-032.
NE...Wind Advisory until 9 PM CDT this evening for NEZ013-014.
     Wind Advisory from 7 AM to 7 PM CDT Friday for NEZ013-014.

&&

$$

DISCUSSION...Dux
AVIATION...Dux