009
FXUS63 KABR 092032
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
232 PM CST Sat Nov 9 2024

.KEY MESSAGES...

- The main focus for accumulating rain will be over north
central South Dakota through this afternoon. Rain and drizzle
chances will diminish to less than a 40 percent chance after 10 pm.

- Fog is expected this evening and overnight behind the rain and
drizzle. There is a 40-60% chance of visibility around 1 mile or
less over the Prairie Coteau of eastern SD.

- Temperatures will be around 10-15 degrees above normal through
Saturday, excluding Monday when temperatures will be near
normal.

- There is around a 25% chance for light rain Tuesday night.

&&

.SHORT TERM /THIS EVENING THROUGH SUNDAY NIGHT/...
Issued at 231 PM CST Sat Nov 9 2024

Thick clouds remain in place across the entire forecast area,
rotating around the surface low centered near LBF/NE at 20Z. Light
rain and drizzle has given way to fog at PIR with visibility down to
around 2 miles. This trend will be common as the main area of rain
over Corson/Dewey/Walworth/Campbell and western McPherson pivots
northeast and out of the forecast area. We will continue to monitor
the trends for fog as increased low level moisture and light winds
increase the potential for visibility to fall to around 1 mile or
less. While there`s only around a 20 percent chance of visibility
falling below 1 mile west of the James River (other than small
pockets here and there), the potential increases to 40-60 percent on
the eastern slopes and just east of the Prairie Coteau of eastern
SD.

Our chances for measurable precipitation drop to less than 30
percent after 06Z as the surface low exits far southeastern SD and
moves into southern MN/northern IA. Expect dry weather Sunday
through Sunday night. Given the recent light rain and relative
humidity remaining at or above 45 percent, fire weather concerns
will be limited. Most locations will stay above 60 percent for
relative humidity Sunday afternoon. The main questions for Sunday
will be temperatures, which could be higher if thicker clouds exit
eastern SD sooner.

Temperatures Sunday will be around 15 degree above normal, ranging
from near 60 degrees over central South Dakota to the low 50s across
eastern South Dakota and west central Minnesota. Look for increasing
clouds Sunday night as a shortwave nears on the northwesterly flow
at 500mb.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
Issued at 231 PM CST Sat Nov 9 2024

Monday morning we will have a weak shortwave departing the region,
with a 1022-1024mb high pressure high following close behind. 850mb
temperatures are already at their lowest at 12Z Monday, with a
gradient across the state from central SD at about +4C to the
northeast/western MN at around -2C. Thus, Monday is expected to be
the coolest of the upcoming days.

As that high pressure moves east and an upper level trough develops
across the intermountain west, lee side low pressure develops over
northeastern Montana leading to a tightening gradient across the
Dakotas/Nebraska. The ~16mb gradient across the state (west to east)
will result in increasing winds out of the south southeast, with
1/2km winds in the GFS topping around 40-45kts. NBM probabilities of
sustained winds of 30mph and gusts in excess of 45mph (advisory
criteria) are between 20-50% and 15-30% respectively which is on par
for most set-ups of this nature.

A cold front comes through Tuesday afternoon through early Wednesday
with limited POPs as the parent shortwave lifts across the area and
strengthens over the Western Lakes region. The cold airmass on the
backside of the system will have a stark contrast to the warm
airmass that precedes it, but overall not a lot of cold air behind
the system as the source region is the Pacific Northwest.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1126 AM CST Sat Nov 9 2024

Terminals KABR,KATY,KPIR,KMBG

VFR conditions remain at all locations except MBG, which has
fallen to MVFR ceilings. Expect ceilings to lower to MVFR at all
locations by 22Z, with IFR conditions by 06Z. LIFR ceilings will
be possible at ATY and PIR due to fog.


&&

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

$$

SHORT TERM...KF
LONG TERM...Connelly
AVIATION...KF