348
FXUS63 KABR 251913
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
213 PM CDT Fri May 25 2018

.SHORT TERM...(This Evening through Saturday)
Issued at 210 PM CDT Fri May 25 2018

In west to northwest flow aloft part of our CWA, where
temperatures are pushing 90, and dewpoints are in the 40s and 50s,
we have already developed scattered convective cells, which
matches the previous forecasters thinking and is backed up by
several CAM solutions. Given this is primarily diabatically
driven, most convection will dissipate by late afternoon/early
evening. That leaves us with weak westerly flow, dry air and
favorable radiational conditions overnight. Most guidance drops
temperatures into the upper 50s and low 60s, so will run with that
(along with taking the normal liberties with the James valley
cold air sink).

A 500mb ridge builds overhead for Saturday. There will also be a
surface ridge axis moving overhead during the day, with low level
westerly flow and good mixing, transitioning to southerly flow with
an increasing gradient. Dewpoints again will crash into the 50s with
temps into the 90s.


.LONG TERM...(Saturday Night through Friday)
Issued at 210 PM CDT Fri May 25 2018

The long term will feature a couple active periods during the time
frame. Initially, ridging aloft is expected to keep the region
mainly dry, especially the eastern CWA through most of the holiday
weekend.  The exceptions being Saturday night and again Monday
night. Increasing LLJ/elevated instability could serve to kick off a
few thunderstorms Saturday night. For Monday night and Tuesday, upper
trof over the western CONUS is expected to shear out across the
Plains, likely in pieces. The GFS is the strongest of the solutions,
and likely the outlier, but at least the other models show a similar
evolution of the trof ejection, just a weaker solution. After that
trof moves through there`ll likely be a lull in activity as mid
level ridge builds again across the western high plains.

Temperatures throughout the period should favor above normal,
especially daytime highs.


&&

.AVIATION...(For the 18Z TAFS through 18Z Saturday Afternoon)
Issued at 1205 PM CDT Fri May 25 2018

VFR conditions for all terminals. Cant rule out a storm near
KATY this afternoon.


&&

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

$$

SHORT TERM...Connelly
LONG TERM...TDK
AVIATION...Connelly