Area Forecast Discussion
Issued by NWS Aberdeen, SD

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937
FXUS63 KABR 031114 AAA
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
614 AM CDT Fri May 3 2024

.KEY MESSAGES...

- Rain expected over south central to northeastern SD and western MN
this afternoon through tonight. A quarter to three-quarters of an
inch of rain southeast of a line from Lyman to Traverse county.

- A much larger system looks to affect the region on Monday, with
widespread moderate rainfall. The threat for severe weather still
appears low at this time (higher across NE/KS/OK), but we will
continue to monitor trends.

&&

.SHORT TERM /TODAY THROUGH SATURDAY AFTERNOON/...
Issued at 459 AM CDT Fri May 3 2024

An upper trough will deepen and trail into South Dakota by
afternoon. At the same time, a warm front will extend into southeast
SD off a Colorado low. The moisture tongue to the north of the front
combined with shortwave energy in the trough could create a set up
for a southwest to northeast oriented band of rain stretching from
Lyman county to Traverse county. Areas southeast of the line have
the potential for up to an inch of rain. Deterministic CAMs are
higher on the QPF than current WPC guidance, but generally expect
over a quarter of an inch in the band with as much as 0.75" locally.
As always with any banded precip, the exact location of the band may
shift. However, it looks like north central SD should remain dry.
Temperatures are expected to remain below normal today in the trough
and rain.

High pressure builds in on Saturday bringing drier weather, but the
upper trough will continue to pull in below normal temps with highs
maxing out in the upper 50s to lower 60s.

&&

.LONG TERM /SATURDAY EVENING THROUGH THURSDAY/...
Issued at 459 AM CDT Fri May 3 2024

Saturday evening we start the long term with an upper level ridge
over the area. This will stay in place through Monday morning.
Monday afternoon/evening an upper level low moves into the region.
Clusters are all pretty close with placement somewhere in the
MT/ND/SD area. Things get a little complicated after that as
deterministic models and ensembles show a cut off high to the north
of this low and a rex block pattern starts to emerge keeping the low
circulating over the region for a few days, through the end of the
period, actually.

Rain chances start to move in Monday afternoon and continue, with
intermittent reductions in probability, through the end of the
period. Looking at NAEFS percentiles, Monday looks to be the wettest
with PWAT values in the 97.5 percentile (mainly west river). NBM is
showing 55 to 65 percent chances of more than a half inch of rain in
24 hours ending Tuesday morning across most of the area. Chances of
more than a quarter of an inch in 24 hours are limited for the rest
of the period. Overall, from Monday through the end of the period,
POPs only drop below 20 percent in isolated areas and for short
periods of time. Strong storms do not look likely at this time.

Along with a rather wet outlook, temperatures starting Tuesday will
be around to 10 degrees below average through the end of the period.
Before we get there, though, Sunday and Monday are expected to have
high temperatures around to about 5 degrees above average due to
ridging and strong WAA. Winds Sunday and Monday are expected to be
quite strong. Gusts Sunday could be as high as 40 mph, perhaps
stronger (especially west river) and around 35 mph on Monday.

&&

.AVIATION /12Z TAFS THROUGH 12Z SATURDAY/...
Issued at 612 AM CDT Fri May 3 2024

Terminals KABR,KATY,KPIR,KMBG

Rain will move into the region this afternoon and affect KPIR and
KATY with MVFR cigs and vsby.

&&

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

$$

SHORT TERM...Wise
LONG TERM...KK
AVIATION...Wise