409
FXUS63 KABR 162315
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
615 PM CDT Tue Jul 16 2024

.KEY MESSAGES...

- A few thunderstorms are possible along and south of Interstate
  90 late this afternoon/early this evening. This area is in a
  Marginal Risk (level 1 of 5) for severe weather. The main
  threat will be 60 mph wind gusts and quarter size hail.

- Dry and mild conditions are expected Wednesday and Thursday.

- 20 to 40% chance of precipitation Thursday night and Friday,
  with the highest chances across central South Dakota.

&&

.UPDATE...
Issued at 611 PM CDT Tue Jul 16 2024

Just updated to extend a low chance for thunder across the
southern half of the CWA through the next hour or two. Otherwise
only minor changes ahead with dry conditions expected.

See update to aviation discussion below...

&&

.SHORT TERM /THIS EVENING THROUGH WEDNESDAY NIGHT/...
Issued at 315 PM CDT Tue Jul 16 2024

An upper level trough will swing across the eastern part of the CWA
tonight, with the region then remaining situated between the trough
to the east and ridging over the western half of the country
Wednesday and Wednesday night.

At the surface, a boundary currently over the southern part of South
Dakota looks to become the focus for thunderstorms later this
afternoon and evening, and a few of those storms could start off
around the Jones/Lyman county area. However, the chances are higher
that the storms will be south of there. High pressure will drop in
from the north later tonight, then will settle over the CWA
Wednesday and Wednesday night. Conditions are expected to be dry
through this time, with winds generally around 10 mph or less.

Low temperatures tonight will be in the mid to upper 50s. High
temperatures on Wednesday will range from the lower 70s across west
central Minnesota and far northeastern South Dakota, to the lower
80s along and west of the Missouri River. Low temperatures Wednesday
night will be in the 50s.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
Issued at 315 PM CDT Tue Jul 16 2024

We start the long term Thursday morning on the downwind side of an
upper level ridge. Friday, a shortwave/low slides down and pushes
the ridge back to the west. Some models are showing this shortwave
strengthening into a weaker low pressure system centered over the
SD/NE/IA border on Saturday. It continues to move south through the
rest of the weekend. Then, for the rest of the term, we are in
northerly flow aloft.

Friday afternoon and evening will have a chance for some
precipitation (30 to 50%, mainly across central SD) as the
shortwave/low comes across. Severe storms do not look likely at the
moment as instability, shear, and lapse rate values are below
favorable thresholds. Some models show rain chances continuing into
Saturday morning. Slight chances (less than 25%) continue through
the end of the period. Accumulations are expected to be less than a
quarter of an inch from each rainfall.

Temperatures through the period will be around average for the most
part, but could dip slightly below average in central SD. Highs are
expected to be in the 80s. We are not looking at any exceptionally
humid days, nor are there any particularly windy days in the
forecast as this time.

&&

.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 611 PM CDT Tue Jul 16 2024

Terminals KABR,KATY,KPIR,KMBG

Aside from a shower passing over KATY and the potential in the
next hour for an isolated weak thunderstorm near the KPIR
terminal, VFR conditions are expected to prevail.

&&

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

$$

UPDATE...Connelly
SHORT TERM...Parkin
LONG TERM...KK
AVIATION...Connelly