727
FXUS63 KFSD 140518
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
1218 AM CDT Sun Jun 14 2026

.KEY MESSAGES...

- Near to below normal temperatures will continue well into next
  week with highs mainly in the 70s to 80s expected.

- Monday night into Tuesday morning is the next opportunity for
  showers and thunderstorms. Severe weather is not expected but
  some gusts of 40-45 mph are possible.

- Shower and thunderstorm chances return Wednesday. At this time
  severe weather is not anticipated. However, trends will need
  to be monitored.

&&

.UPDATE...
Issued at 844 PM CDT Sat Jun 13 2026

The forecast as of 9pm remains on track. Winds will decrease
overnight becoming light. Lows will fall into the upper 40s to low
50s. Winds will remain northwesterly for Sunday and breezy with
gusts of 15-25 mph. High pressure will build into the region through
the day Sunday. Conditions will be pleasant with sunny skies and
highs in the 70s. Monday the high pressure progresses south of the
region and an upper wave and associated surface low will begin to
move in from the northwest. Winds at the surface will become
westerly and breezy gusting to 25 mph. WAA will boost afternoon
highs into the upper 70s to low 80s.

Monday night into Tuesday morning a shortwave will work through the
region bringing chances for showers and thunderstorms. Convective
parameters over all do not support severe weather. However, there is
enough elevated instability to get some lightning. Soundings
indicate the air mass beneath the cloud layer is very dry. As a
result some storms may produce wind gusts to around 40-45 mph.

Wednesday better chances for showers and thunderstorms exist.
Uncertainty in how much instability will be available leaves
confidence in any strong or severe thunderstorms low at this time.
However, we will need to monitor the trends for changes.

&&

.DISCUSSION...
Issued at 121 PM CDT Sat Jun 13 2026

Mid level moisture around 700 mb and moderate lapse rates above this
layer will lead to CAPE values of about 500-1000 J.kg through the
afternoon. This should generally be confined to areas near and
south of a Sioux City to Storm Lake line. With elevated shear values
sitting around 40-50 knots an isolated stronger updraft or two will
be possible with hail to the size of dimes and nickels the main
threat. Broad troughiness will push this mid level convergence and
steeper lapse rates south of the area this evening, leaving behind
dry and cool conditions for tonight.

Broad low pressure across central and eastern Canada will keep
cooler northerly flow in place through Monday. Lows in the 40s to
lower 50s and highs mostly in the 70s are expected.

There will be a weak piece of energy dropping into the area Monday
afternoon and evening, mainly to the north of the area. Decent
surface heating should lead to 250 to 500 J/kg CAPE and with a very
dry subcloud layer creating a fairly classic inverted V sounding,
wind gusts of 40 to 50 mph will be possible.

A strong upper level jet will spill into the Northern Plains Tuesday
through Thursday and bring the next chance for showers and
thunderstorms. For now it appears that this will bring some very
strong elevated shear into the area so it will be a matter of timing
and how much instability that this pattern can support to bring a
threat for severe weather. For now it appears that instability will
be on the low side, but if we can somehow get 1500 J/kg or so with
this shear we would see some severe weather, Something to watch out
for.

Confidence on any details Thursday into Saturday a little lower as
fairly strong northwest flow continues. Any wave will bring warmer
temperatures ahead and cooler behind, so that will determine a lot
and will need to wait to see how things play out.

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1218 AM CDT Sun Jun 14 2026

VFR conditions are expected to prevail this period. Skies will be
clear and northwest winds will be light. Wind gusts increase to 17-
22 kts beginning mid-morning Sunday and peak in the mid-afternoon.
Winds decrease after sunset, becoming light and variable overnight.


&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
IA...None.
NE...None.

&&

$$

UPDATE...AJP
DISCUSSION...08
AVIATION...AJP