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000
FXUS63 KABR 142341 AAA
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
641 PM CDT Sun Apr 14 2024

.KEY MESSAGES...

- Mild again Monday with highs 10 to 20 degrees above normal.
  Monday will see increasing winds and low afternoon relative
  humidity, raising the fire danger to the very high category.

- Low pressure will bring likely chances for measurable rain to
  the region Monday night through Wednesday morning (60-90%).
  48hr probabilities for an inch (40-60%) of rain are high over
  eastern South Dakota.

- Cooler temperatures, around 10 to 15 degrees below normal, can be
  expected for the latter half of the week.

&&

.UPDATE...
Issued at 634 PM CDT Sun Apr 14 2024

Aviation discussion updated below for the 00Z TAFs.

&&

.SHORT TERM /THIS EVENING THROUGH MONDAY NIGHT/...
Issued at 309 PM CDT Sun Apr 14 2024

At 2 pm CDT, temperatures are warming through the 60s into the 70s
under a sunny sky. Winds around the surface high pressure over the
region continue their shift from north to east or southeast,
generally in the 5 to 15 mph range with some gusts occasionally
getting above 20 mph.

Lee-of-the-Rockies surface troffing gets going overnight as the
upper low over the southwest CONUS begins to move toward Colorado.
The pressure gradient that forms, between falling pressure to the
west/southwest and this surface high over the region, will help to
keep winds from dropping completely off overnight and will help to
keep temperatures mild again tonight. There is still a low level jet
signal showing up tonight in the models. Still can`t completely
dismiss the potential for some isolated/widely scattered elevated
showers or perhaps even a thunderstorm later tonight into Monday
morning, given the steepness of mid-level lapse rates. Tough to
discern if there is actually a shortwave moving out of the Rockies
toward this region for the overnight or if enough mid-level moisture
will be available to aide precipitation potential. Continued the
smallish pops (generally at or below 30%) for late tonight into the
first half of Monday.

The airmass over the region is pretty dry (dewpoints down into 20s
to around 30 degrees), and this airmass is expected to get recycled
on Monday for probably most of the day before the 20 to 30 mph winds
with gusts to, at least, 40 mph finally begin to draw some higher
moisture content air (down in TX/OK/KS and MO right now) in the
boundary layer up into the region. Using CONSRaw and RAP13 guidance
to augment ensemble-based dewpoints/RH for Monday resulted in
afternoon RH values reaching or getting close to Red Flag criteria.
The wind criteria will be achieved, and fuels are still in a "yes"
category for "able to expand or grow rapidly". So, collaborated a
Fire Weather Watch for Monday for north central South Dakota and
portions of central and northeast South Dakota. And, maybe, areas
that don`t see a fire weather headline on Monday might need a wind
advisory?

The western, but especially the southwestern, forecast zones could
see a few (strong?) thunderstorms by late Monday evening. This is
where the strongest instability (MLCAPE of ~500-1000J/kg) and deep
layer shear (of ~25 to 30 knots) are forecast to be at 00Z. The
latest depiction in CAMs still shows good WAA forced/PVA lifted
precipitation chances working from south to north later Monday night
on the front side of the upper low as it begins to take shape/lift
out onto the central plains (KS/NE).

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 309 PM CDT Sun Apr 14 2024

A somewhat active mid level flow is anticipated for the long term.
At the start of the forecast (Tuesday), a split flow pattern is
evolving over the CONUS. A decent looking upper wave will be moving
across NE/IA and into WI by Wednesday. This low will remain
relatively progressive as more energy dives into the PacNW, forcing
the low to keep moving. Several waves will rotate around this upper
low as it advects across the Plains, bringing rain to the forecast
area for Mon night through Wednesday morning. NBM 48hr probs for an
inch of QPF are pretty high over the eastern CWA (40-60%) during
this time period. Bump up to 2 inches and 48hr probs drop
precipitously. Of course, deterministic model runs are a bit less
enthusiastic with the coverage of rain. Meanwhile, by Wed afternoon,
most of the pcpn associated with the upper low should have moved off
to the east. However, a positive tilt upper trof centered over SC
Canada will provide for cooler temps, and some pcpn chances for late
week. 2m temps start the period above normal, but are forecast to
fall below normal on Wednesday, and remain there until next weekend.

&&

.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 634 PM CDT Sun Apr 14 2024

Terminals KABR,KATY,KPIR,KMBG

VFR conditions are forecast through the TAF period. Increasing
southeast surface winds will gust over 30 to 35-40 knots by
Monday afternoon. Low-level wind shear (LLWS) looks to be a
concern for KPIR during the overnight hours, and have inserted
mention of this in the TAF.

&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...Fire Weather Watch from Monday afternoon through Monday evening
     for SDZ003>006-009>011-015>020-022-023-034-036-037-051.

MN...None.
&&

$$

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