885
FXUS63 KABR 132015
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
315 PM CDT Mon May 13 2024

.KEY MESSAGES...

- Smoke lingers, albeit less dense ahead of the next system
  Tuesday.

- Precipitation chances develop early Tuesday out west and increase
  through the day, lingering through Tuesday night before departing
  Wednesday. Precipitation chances range between 40-70%

- Precipitation returns Thursday afternoon and evening (15-30%
  chance).

- Temperatures to remain seasonal for next several days.

&&

.SHORT TERM /THIS EVENING THROUGH TUESDAY NIGHT/...
Issued at 309 PM CDT Mon May 13 2024

High pressure remains in charge tonight into Tuesday. HRRR/RAP smoke
models shows some lingering low concentrations across the area prior
to the arrival of the next system. Tuesday should feature some
warming before precipitation moves in. Timing varies a little
between CAMS, however generally should see scattered showers coming
into the far west a few hours after midnight, expanding east while
weakening, with a more concentrated area of weak convection more
towards mid day Tuesday, and slowly progressing east through the
course of the day into Tuesday night.

As for moisture, with it being convective season there will
naturally be a wide spread in amounts, however generally speaking
ensemble CAMS run an average of between a few hundreds in eastern
SD/western MN to about a half inch in central SD. 25th/75th
percentiles reflect the aforementioned variability with 1 to 2 tenths
on the low end to 3/4 of an inch at the high range across the
Missouri valley. Severe weather remains unlikely with skinny CAPE
and generally stable profiles in BUFKIT. Mean CAPE only runs between
100-200j/kg during peak heating Tuesday.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Issued at 309 PM CDT Mon May 13 2024

An unsettled weather patten will continue for the long term as
Clusters agree on the overall placement of the shortwave that will
be over the Northern Plains, with the axis from northern SD through
central SD at 12Z Wednesday. Minor differences exists on the
intensity as Cluster 2 (77% GEFS/6% EC) and Cluster 3 (32% EC/10%
GEFS) indicates a deeper shortwave than Clusters 1/4. Ensembles
indicate the 850mb elongated low centered over the Dakotas with GEPS
being the outlier as it keeps this low more north into ND/Canada.
The 850mb/surface cold front is forecasted to be draped southward
over central SD early Wednesday morning as northwest flow is
indicated behind it. By Wednesday evening, the entire CWA will be
behind the cold front/CAA as this low (with ENS/GEPS having this
become an open wave) is well off to our east and northeast. Another
shortwave swings down from the northwest Thursday morning as a broad
850mb low forms over central Canada and hangs out over the Northern
Plains/Canadian border into Friday. Clusters really diverge at this
point into the weekend with the exact placement and intensity of
this low and its frontal features as it will slowly push eastward
through the weekend. So low confidence exists on exact setup this
far out.

Ensembles indicate ongoing rain showers, mainly over our central and
eastern CWA Wednesday morning as we start to see dry air move in
over the western CWA from a high. NBM Pops from 12Z Wednesday-00Z
Thursday range from 20-70% highest from the James River Valley and
eastward, near the low, with precip tapering off west to east
through the evening. By Wednesday night into early Thursday we will
see a period of brief dry weather with the high pressure system
before rain chances return Thursday afternoon through Friday (20-30%
pops). Pops of 15-30% continue into the weekend. Closer to time we
will have a better understanding when models start to come together
so pops remain pretty broad due to the model variability. WPC Plumes
for QPF, ending at 00Z Thursday for KABR, show a mean of around
0.33". Similar QPF totals, give or take a few hundredths, are noted
for KPIR/KATY, and around 0.41" for KMBG. GEFS Plumes for QPF are
similar. Latest NBM QPF follows this and generally shows QPF for
Tuesday and Wednesday at or below 0.50", with the highest around the
Missouri River. Prob of CAPE>500 j/kg and shear>30kts for Thursday
is low at 5-10%. So organized severe threat is low, however, we
could be dealing with high shear low CAPE thunderstorms Thursday
afternoon into the night.

Cooler temps for Wednesday behind the front with highs in the mid
60s to around 70. Gradual warming back into the 70s for the end of
the week into Saturday with a cooldown again for Sunday.

&&

.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 1233 PM CDT Mon May 13 2024

Terminals KABR,KATY,KPIR,KMBG

VFR conditions for all terminals. Winds will be north northeast
shifting to easterly through the TAF period.


&&

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

$$

SHORT TERM...Connelly
LONG TERM...MMM
AVIATION...Connelly