154
FXUS63 KFSD 060654
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
154 AM CDT Sun Apr 6 2025

.KEY MESSAGES...

- More Spring-like conditions expected through the middle of
  the week, with dry weather continuing.

- Next chance of rain arrives late Tuesday night and continues
  into Thursday, though probabilities for more than 0.10" of
  rain are only around 25%.

- Temperatures by the end of this week and into this weekend
  are expected to rise above normal and even into the 70s by the
  weekend.

&&

.DISCUSSION...
Issued at 151 AM CDT Sun Apr 6 2025

THIS MORNING: A mostly clear sky continues across the region,
though there are some signs that cirrus will increase by
daybreak. Winds remain highly variable, leading to strong
decoupling and lows into the lower 20s in valley area, but
slightly stronger winds in elevations keeping lows in the 30s.

TODAY: Broad low-lvl warm advection spills into the Plains
through the day on Sunday, with surface winds turning southwest
to westerly in the afternoon. Soundings suggest deep mixing AOA
700 mb by mid- afternoon, both tapping into and mixing down a
layer of fairly dry air to the surface, but also encouraging
highs towards the 60 degree mark. While RH values fall into the
20 to 25% range in many areas, winds are expected to stay below
critical levels. Therefore no fire weather hazards are
anticipated.

TONIGHT: A cold front currently over southern Canada will arrive to
the Highway 14 corridor this evening.  This front will switch winds
towards the north through the late evening with just a gradual
cooldown in temperatures.  Soundings indicate potential for some mid
20 knot wind gusts as the front arrives.

MONDAY: High pressure moving through the western Great Lakes keeps a
northerly wind in place through Monday.  Meanwhile, seasonally cool
low-lvl temperatures arrive with 850mb temperatures near -6C by
Monday afternoon.  The end result will be temperatures 10 or more
degrees below normal in the 40s.

TUESDAY:  In response to mid-lvl troughing crossing the Pacific
Northwest and moving into the Northern Rockies, we`ll see 850 mb
ridging slide through the Tri-State area early Tuesday morning.
Broad low-lvl warm advection through the plains will bring an
increase in mid-lvl clouds early Tuesday, with the tightening SPG
leading to a breezy southeasterly wind in the afternoon.
Temperatures with the SE flow will warm into the 50s.   By the
overnight hours there are some indications that we`ll see increasing
focus along a developing 850 mb front through the Tri-State area.
Weak elevated instability AOA 200 J/KG will develop and if we can
have sufficient moisture convergence, then a few isolated
showers and even a thunderstorm may form and track southeast
through daybreak.

WEDNESDAY-THURSDAY: Mid-lvl vorticity slides southeast through the
region Wednesday and Thursday, bringing occasional risks for showers
to the region.  The lack of appreciable moisture and general focus
of the LLJ well southeast of the area should lead to just very light
QPF, which is supported by both the NBM and LREF only indicating
around a 25-35% probability of more than 0.10" over the 48 hour
period. Temperatures climb just a bit warmer both days, with highs
reaching into the lower 60s.

FRIDAY-SUNDAY: Large scale ridging moves into the central US by
Friday and continues through the weekend.  This pattern will set us
up for warmer than normal temperatures through the weekend. In fact,
probabilities of highs over 70 degrees climb to over 70% both days
of the weekend, and potential to reach 80 degrees is certainly
possible Sunday. With gusty southerly winds on Saturday, modest
fire danger may develop. While currently a dry forecast into
Sunday, the passage of a weak trough could bring some high based
showers into the area for Sunday.

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1030 PM CDT Sat Apr 5 2025

Light/variable winds will settle out to west-southwest through
the early-mid morning. After 06/18Z, west-northwest winds will
be more prevalent with occasional gusts 15-20kt. Early evening
winds decrease toward sunset, but northerly winds behind a cold
front pushing southward will bring gusts 20-25kt as far south as
the I-90 corridor by the end of this TAF period.

VFR conditions are expected through the period.

&&

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

&&

$$

DISCUSSION...Dux
AVIATION...JH