National Weather Service National Headquarters

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

-- Discussion containing changed information from previous version are highlighted. --
000
FXUS63 KABR 211728 AAC
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
1228 PM CDT Sun Apr 21 2024

.KEY MESSAGES...

- Warmer temperatures in the 60s finally return today. Other than
  Tuesday, much of the 7-day forecast calls for near to above
  normal temperatures.

- The precipitation potential looks minimal for Monday with a
  10-15% chance of light rain/sprinkles, mainly along the ND/SD
  border into western MN. An active pattern may develop for the
  second half of the upcoming week.

&&

.UPDATE...
-- Changed Discussion --
Issued at 1226 PM CDT Sun Apr 21 2024

Aviation discussion updated below for the 18Z TAFs.

UPDATE Issued at 1017 AM CDT Sun Apr 21 2024

Sunny skies will prevail today as temps rise into the low to mid
60s for most areas. Will be keeping an eye on the wind gusts and
humidity trends across central/north central SD this afternoon in
regards to elevated fire weather conditions. Otherwise, the going
forecast for today needs little, if any changes up through 00Z.
-- End Changed Discussion --

&&

.SHORT TERM /TODAY THROUGH MONDAY AFTERNOON/...
Issued at 310 AM CDT Sun Apr 21 2024

Short term models agree on a positive tilted ridge moving in
overhead towards late morning into the afternoon with the 850mb and
surface ridge over the Northern Plains as the surface high remains
positioned over the central U.S. This will provide dry conditions
through the day and tonight. The ridge will sink southeast
tonight/overnight as a shortwave trough moves in, associated with a
mid level low to our north. The surface low is forecasted to occlude
over Saskatchewan early Monday with a secondary low forming over the
CWA (then dissipating) as a frontal boundary will push across our
CWA through the day.

Precipitation wise, HREF models continue to back off on precip as
most of it will stay northward and eastward into MN. It does show
some light returns at most over northern and northeastern SD/western
MN, so pop chances remain pretty low ranging from 10-15% across this
area. Prob of QPF>0.01" is only 10-15% as soundings show dry low
levels, so could be more of a virga situation or light rain at most.
Southwest winds overnight into early Monday, along with an
inversion, will lead to gusty winds over and downslope of the Coteau
with winds increasing to 15-25kts and gusts 25-35kts from 06-12Z,
per HRRR/NBM, and decreasing by mid morning/afternoon. On the other
side of the CWA, low level lapse rates/pressure gradient does
steepen behind the front Monday which will lead to winds increasing
across north central to parts of central SD. Gusts could reach 30-
40kts, highest over Corson/Dewey counties. With the gusty winds and
RH values in the upper teens/lower 20s we will need to watch for
fire concerns, mainly over north central SD.

As winds shift more southwesterly at 850mb to surface this
afternoon, this will bring in warmer air with 850mb temps ranging
from +2 to +6 by 00Z. Mixing into or close to this level, surface
highs are forecasted in the upper 50s to mid 60s and warmer temps
tonight in the upper 30s to lower 40s as winds will be out of the
south/southwest. Highs for Monday will be a few degrees warmer,
ahead of the front over our eastern CWA.

&&

.LONG TERM /MONDAY EVENING THROUGH SATURDAY/...
Issued at 310 AM CDT Sun Apr 21 2024

The period opens Monday evening with an area of low pressure
straddling the U.S./Canada border over Manitoba/North Dakota. The
upper low dives southeast through the Dakotas and western Great
Lakes region through the end of the day Tuesday. It should drag a
cold front southward through the CWA, turning winds to the north-
northwest and ushering in some cooler conditions for Tuesday/Tuesday
night. The first half of the day Tuesday could be rather blustery
with sustained winds of 15 to 25 mph with gusts over 30 mph. Surface
high pressure briefly takes up residence over the Dakotas
Tuesday/Tuesday night. Then, return flow south/southeast winds and
daytime heating should warm things back up into, at least, the 60s
on Wednesday while mid/upper level heights rise. Beyond Wednesday,
areas of low pressure over the western CONUS are progged to move out
across the central/northern plains through the weekend. In house
ensemble PoPs show this ramp up of precipitation potential well
enough, with a couple of forecast periods maintaining likely (55% or
higher) PoPs out in Day 4/Day 5 timeframe right now.

Presently, normal highs range from the upper 50s to low 60s and
normal lows are in the low to mid 30s. Tuesday is currently forecast
to be the coolest day of the period, with highs in the upper 50s.
The rest of the period should exceed "near normal" for high
temperatures.

&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
-- Changed Discussion --
Issued at 1226 PM CDT Sun Apr 21 2024

Terminals KABR,KATY,KPIR,KMBG

VFR conditions are forecast through the TAF period. West to
southwest surface winds at the start of the period will gradually
become southerly this evening, before switching to the northwest
on Monday behind a passing frontal boundary.
-- End Changed Discussion --

&&

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

$$

UPDATE...TMT
SHORT TERM...MMM
LONG TERM...Dorn
AVIATION...TMT