Scientific Forecaster Discussion
Area forecast discussion...updated
National Weather Service Aberdeen South Dakota
1234 am CDT Wednesday Sep 3 2014
06z aviation forecast discussion below.
Short term...tonight through Thursday night
Precipitation chances remain the main issue in the short term. For tonight am
still expecting some late night elevated activity on the nose of
low level jet over the eastern County Warning Area. However given prognosticated mixed and
MUCAPE...coverage looks to be scattered at best. On Wednesday elevated
mixed layer is expected to advect northeast overtop increasing ll
moisture/instability. The eml may provide enough of a cap to keep
most convection at Bay late Wednesday and Wednesday night. GFS
bufr soundings still indicate a fair cap late afternoon/evening over
the northeast County Warning Area. However just in case weak energy aloft provides
enough lift...will keep low probability of precipitation in place. Front blows through
late Wednesday night and Thursday with most activity expected to
ride the cap across North Dakota and into Minnesota. After a few
early morning showers Thursday should be dry and cooler vs
Wednesday...which will be the warmest day this week. Thursday
night should be chilly as surface high builds in from the west/north.
Long term...Friday through Tuesday
Extended period shaping up to be rather quiet as high pressure
dominates the weather pattern to start things off. Surface high is
centered overhead at 12z Friday...with what is shaping up to be a
rather cool morning. Through Sunday...this high slowly shifts east
which will likely allow for pleasant temperatures and dry conditions.
Beginning Sunday night and lasting through Tuesday...pressure
gradient tightens as low pressure begins to develop over the High
Plains. Low level moisture increases as well...so could be going
back into a few days of active weather early next week after a
weekend of tranquil conditions.
06z tafs for the kabr...Katy...kpir and kmbg terminals
VFR conditions will prevail through the taf forecast period at
kabr...kmbg and kpir. Katy is likely to get into some low stratus
by 12z-13z Wednesday from northward advecting low level moisture.
Ceilings at Katy are expected to lift into lower end VFR range by middle-
day. With all the necessary ingredients to get night-time
thunderstorms to develop...went ahead and also tossed in a tempo
group for ts for a couple hours toward sunrise at Katy. Will
continue to monitor.