Area Forecast Discussion
Issued by NWS Aberdeen, SD

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS63 KABR 280946
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
446 AM CDT Thu Mar 28 2024

.KEY MESSAGES...

- A disturbance moving through the region late tonight into Friday
will deliver a 30-50% chance for rain and/or freezing rain. Up to a
few hundredths of ice accumulation will be possible.

- Precipitation chances increase this weekend, perhaps in two waves,
late Saturday/Saturday night, then again late Sunday through Monday.
Early indications suggest a "less than 6 inch type outcome" for the
time being.

- Warming temperatures moving in by mid-week next week, with 40s,
50s, and perhaps even 60s (central SD on Wed) moving into the region.

&&

.SHORT TERM /TODAY THROUGH FRIDAY AFTERNOON/...
Issued at 445 AM CDT Thu Mar 28 2024

We`ll be able to squeak out another relatively quiet day weather-
wise today before a disturbance moves into our region toward the
latter half of the period and generate some precip chances for parts
of the forecast area. High pressure will gradually shift east and
southeast of our area today while a low pressure trough continues to
organize across the Rockies and Northern High Plains. With a ridge
of high pressure aloft, we can expect a fair amount of sunshine
during the day, perhaps high clouds filter out some of that sunshine
this afternoon. Warmer daytime highs are expected today, with
eastern zones the coolest thanks to thicker snow cover. A tighter
pressure gradient develops this afternoon across the western and
central Dakotas between the high to the east and the trough to the
west. Increasing southeast breezes gusting up around 30 mph will be
possible across the Missouri Valley.

Clouds will increase tonight as a sfc trough shifts eastward across
the Dakotas. The upper ridge will give way to an upper trough
lifting northeast out of the Rockies and Northern High Plains. We
anticipate light precipitation to develop and shift east-
northeastward across our forecast area tonight into Friday. Models
seem to be in agreement on the core of this disturbance to pivot out
of Montana and into North Dakota keeping the focus for steadier QPF
to our north. BUFKIT soundings do show a warm nose(above freezing)
aloft, just off the surface with temperatures at or colder than
freezing at the surface. That warm nose will take some time to
saturate, but eventually it looks to and we should see a period of
freezing rain spread across the forecast area late tonight into
Friday morning. WPC QPF and NBM generally are in the same camp
indicating up to a few hundredths of ice accumulation will be
possible across the northern tier of our CWA.

&&

.LONG TERM /FRIDAY EVENING THROUGH WEDNESDAY/...
Issued at 445 AM CDT Thu Mar 28 2024

Surface high pressure will be moving over the region Friday night
through much of the day Saturday, before pushing east Saturday night
as the first wave of precipitation chances approach. In regards to
the precipitation over the weekend into Monday, latest deterministic
solutions are starting to show this in two waves now, the first
being Saturday night, with the more meaningful onset of precip late
Sunday through Monday. Inherited NBM PoPs, as well as ensemble probs
for measurable still fail to adequately portray this given their
more blended/averaged feel. Will have to watch to see if this a
trend that holds.

By 00Z Tuesday, probability of exceedance for accumulated snowfall
greater than 3 inches (assuming 10:1 ratios) are running from around
40-60% across central SD, with lesser amounts around 40% or below
further east. Snowfall means amongst the GEFS/ENS/GEPS are running
around 2 to 4 inches by 00Z Tuesday, with some higher end scenarios
(75th percentiles) on the order of 4 to 6 inches (mainly over
central SD).

Looking ahead to mid-week next week, we see signs in the cluster
output of overall ridging trying to build across the Northern
Plains. There still area some glaring differences in the upper level
patterns amongst the four clusters in the 00Z Thurs - 00Z Fri
period. Clusters 2 and 3 (with 20% and 19% membership respectively)
hold on to a much deeper and slower moving trough over the Great
Lakes, which in turn show a large ridge amplification over the
High/Northern Plains. Cluster 1, which has the largest membership at
43%, shows a more flattened upper level pattern over the region, but
still mild nonetheless. The differences can be seen in 850mb temps
as well, with the more amplified ridge scenario running between +7C
to +12C across the CWA. Grand Ensemble of the clusters are generally
between +3C and +7C from east to west across the CWA. All that said,
the overall ridging moving in will mean a warm up into the 40s and
50s likely, perhaps even 60s on Wednesday across central SD
according to the inherited NBM temperatures.

&&

.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...
Issued at 1237 AM CDT Thu Mar 28 2024

Terminals KABR,KATY,KPIR,KMBG

VFR conditions are expected to prevail at all 4 TAF sites during
this forecast period. Clear skies and light and variable winds
through the early morning will become southeasterly during the
daytime hours. Breezy conditions are anticipated at KPIR and KMBG
this afternoon with gusts between 20-30 kts. One thing we`ll have
to keep an eye on during the pre-dawn hours is fog development.
Latest guidance suggests some fog will develop south of the KATY
aerodrome over the course of the next several hours. At this time,
left mention of it out in the forecast for KATY.

&&

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

$$

SHORT TERM...Vipond
LONG TERM...TMT
AVIATION...Vipond


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.