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FXUS63 KABR 012307 AAA

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
607 PM CDT Sun Oct 1 2023

.SHORT TERM...(This Evening through Monday Night)
Issued at 150 PM CDT Sun Oct 1 2023

Key Messages:

* Gusty southerly winds and above normal temperatures.
* Rainfall chances (50-80%) ramping up Monday night.

Warm front has pushed north of the area, leaving the CWA within the 
warm sector. Temps are in the upper 80s to around 90 degrees across 
the region, with gusty southerly winds. Sisseton has already set a 
record high with 91 degrees at the 18Z observation. A couple more 
records are possible before the end of the day. Will also likely be 
setting records for the warmest low temperature for Oct 1st. 

For tonight, we remain in the warm sector while the frontal boundary 
establishes itself over western SD. Precip chances look minimal at 
best over the western CWA, even with the low-level jet in place. 
That said, there are two areas to watch tonight into Monday morning 
in regards to potential showers. One is along the front across 
western SD, which looks to mostly miss the western CWA fringe 
according to HREF reflectivity ensemble paintball. Another area is 
across southeast SD, up through east central SD into western MN, 
again based on paintball output. These areas are non-zero POPs, but 
not high enough to be mentionable for the time being. Breezy 
southerly winds will remain in place overnight, especially east of 
the Missouri. Expecting mild lows with many areas stuck in the 60s.

Frontal boundary does not move too much Monday into Monday night, 
but we will see some progress into central SD. As shortwave energy 
ejects eastward and approaches the region, showers and thunderstorms 
are expected to develop across western SD, and eventually into the 
central part of the state as we head through the Monday 
evening/nighttime hours. Currently have fairly high (50-80%) chances 
across the western CWA Monday evening/night. Cannot rule out a few 
strong to severe storms as well.

.LONG TERM...(Tuesday through Sunday)
Issued at 150 PM CDT Sun Oct 1 2023

Key Messages:

* Showers continue through Tuesday evening, otherwise expect mainly 
  dry conditions.
* Cooler air moving in with below normal temperatures from 
  Wednesday. Potential for frost Saturday morning and Sunday morning.

We'll start out 12Z Tuesday the with opened up 500mb trough set up 
to our west, across Alberta/Saskatchewan down through MT/WY and 
UT/CO with southwest flow over the Dakotas and MN.The surface low 
will be quickly surging north and be across the western half of ND 
by 12Z Tuesday, with a cold front stretching across western SD. 
While most solutions keep the rain west of the James River prior to 
daybreak Tuesday, some do already have showers moving into eastern 
SD. Will go with around 20% chances for measurable rain east to 
start off, increasing to 50-70% in the afternoon cwa-wide. Although 
there is still strong shear, CAPE values diminish significantly 
Tuesday. There's still time for changes between now and then, but 
the idea of keeping thunderstorms in the chance range or less still 
looks reasonable through Tuesday evening. The cold front stretching 
n-s over central SD at 18Z Tuesday will reside over our eastern 
counties by within a few hours, taking most of the precipitation 
with it. Specifics on how much rain will fall over our eastern 
counties Tuesday afternoon is still unknown, with the 12Z GFS on the 
extreme end with several counties potentially getting close to 1" of 
rain between 21Z Tuesday and 03Z Wednesday. Will keep with a more 
consensus/modest forecast at this point.

Out of anything over the long term period, we're most confident on 
the temperatures. There is limited variability in the forecast highs 
and lows through at least Friday on the order of around 5 degrees or 
less most days. After 850mb temperatures of 15-near 20C at 12Z 
Tuesday they will fall into the single digits by 06Z Wednesday. 
Single digit below 0C 850mb temperatures will show up as early as 
Thursday night across our northeastern counties, as the upper level 
trough lingers overhead. Temperatures Saturday morning and Sunday 
morning could fall below 36 degrees, with around a 40 percent chance 
over the Leola Hills and the remainder of north central SD Saturday 
morning, and around a 15% chance Sunday morning over much of the 
area. We will continue to monitor the temperature trends for the 
upcoming weekend, with the potential for frost/freeze conditions.


.AVIATION...(For the 00Z TAFS through 00Z Monday Evening)
Issued at 605 PM CDT Sun Oct 1 2023


VFR skies/vsbys are expected overnight, except for around KMBG
where early morning low cigs may form for a time.