Pierre, South Dakota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

712
FXUS63 KABR 250516 AAC
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
1216 AM CDT Fri Apr 25 2025

.KEY MESSAGES...

- Scattered rain showers will come to an end from west to east
  tonight, leaving dry and warmer conditions in place for Friday.

- The next chance of rain (65 to 85%) will be for the second half
  of the upcoming weekend into early next week. There is a 15%
  chance for severe storms east of the James River Monday.

&&

.UPDATE...
Issued at 815 PM CDT Thu Apr 24 2025

Rain continues to work across the James River valley and points
east in the CWA. This precipitation should clear the eastern edge
of the CWA within a few hours. Generally, a trace to a couple
tenths of an inch of rain can be expected. No changes planned at
this time.

UPDATE Issued at 614 PM CDT Thu Apr 24 2025

See below for an aviation forecast discussion for the 00Z TAFs.

&&

.SHORT TERM /THIS EVENING THROUGH FRIDAY NIGHT/...
Issued at 305 PM CDT Thu Apr 24 2025

An upper level shortwave trough currently over eastern Nebraska will
track to the east tonight, leaving a more zonal flow pattern in its
wake over the region. This pattern will give way to a building ridge
Friday afternoon and Friday night.

At the surface, a boundary currently extends from Colorado to Iowa,
with scattered rain showers to the north of it tracking across parts
of the CWA. Another area of rain over western South Dakota will work
its way over central South Dakota during the late afternoon hours,
then will spread eastward this evening, weakening as it does as high
pressure drops in from the north. Overall, the precipitation should
come to an end between 06Z and 12Z. The high will be the dominant
feature over the area Friday and Friday night, keeping conditions
dry during this time.

Low temperatures tonight will be in the mid 30s to lower 40s. High
temperatures on Friday will be in the upper 50s to mid 60s. Lows
Friday night will be in the mid 30s to lower 40s.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
Issued at 305 PM CDT Thu Apr 24 2025

An area of high pressure over central and eastern SD will start to
move out of the state early Saturday morning. The pressure gradient
between this high pressure and a low pressure to the southwest will
increase wind speeds aloft over central and eastern SD Saturday and
Sunday. Stronger lapse rates during the afternoons will help to mix
these winds to the surface, with the NBM showing widespread wind
gusts over 25kts west of the Prairie Coteau Saturday and the
strongest winds west of the Missouri River gusting over 35kts.
Sunday afternoon, the winds over the James River Valley increase
again, with the strongest gusts looking to be up to 30kts. Warm air
will also start to move into central and eastern SD Saturday
afternoon behind a warm frontal passage, increasing temperatures
Sunday in the 70s to lower 80s. Despite these warmer temperatures,
the winds from the south will help to move mid-level and surface
moisture into SD, keeping relative humidity values above 30% on
Saturday and 45% Sunday. This humidity as well as the ground
starting to green up will likely reduce the fire weather risk
Saturday and Sunday despite the higher winds in the afternoon.
Additionally, with the passage of the warm front, there is a slight
chance (20-30%) for scattered precipitation development over central
and eastern SD Saturday into Sunday morning, though rainfall amounts
look to be very light.

A surface low pressure will start to move over and through SD Sunday
afternoon into Monday, increasing the chance for precipitation to
widespread 65-85% chance Sunday evening into late Monday evening.
There is variability in the models as to the location and the timing
of the highest rainfall amounts. The NBM shows a 30-50% chance for
0.75 inches of rainfall accumulation highest over the James River
Valley by Monday evening where as the clusters have a 30-40% chance
for three quarters inch and a 20-60% chance for a half inch highest
over northeastern SD by early Tuesday morning. After that, a surface
high pressure looks to move into central and eastern SD, keeping the
chance for precipitation low through Wednesday.

There is the potential for severe weather with this system Sunday
and Monday. The clusters are showing 20-60% for surface CAPE over 500
J/kg and shear greater than 30kts over central SD Sunday afternoon.
The warm and moist air Sunday afternoon, as well as higher
instability and shear helps to set up a good environment for severe
weather development. However, the clusters are showing a cap over
the area, with CIN values of -100 to -200 J/kg, which will help to
inhibit the potential for severe weather to develop Sunday afternoon
into the evening. Monday afternoon continues the risk for severe
weather, with 30-70% for surface CAPE over 500 J/kg and shear
greater than 30kts over eastern SD as well as moisture and very
little to no cap, with CIN values of -50 J/kg or less. There are
however differences in the models on this, with the details needing
to be ironed out more as the chance for severe weather gets closer.

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1213 AM CDT Fri Apr 25 2025

Terminals KABR,KATY,KPIR,KMBG

MVFR stratus is developing across central SD tonight and is
currently affecting KPIR. Will also need to watch for fog
development toward morning at KMBG and KABR after the recent
rain. Conditions are expected to improve to VFR at all sites by
16z.

&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
&&

$$

UPDATE...10
SHORT TERM...Parkin
LONG TERM...12
AVIATION...20