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Area forecast discussion...updated 
National Weather Service Aberdeen South Dakota
1046 am CDT Wednesday Apr 23 2014 of today

Had to extend the mbg area Wind Advisory until 18z due to strong
winds continuing at mbg. Otherwise...let the central South Dakota portion of
the advisory expire at 15z as winds have died down due to the
approach of the surface trough. Still expecting gusty southeast winds
to continue through the day across eastern portions of the County Warning Area.
Also seeing scattered showers and a few lightning strikes moving across
the County Warning Area within warm air advection zone ahead of approaching cold front. Current
temperatures are struggling to climb due to cloud cover and
precipitation...although satellite trends are showing breaks in the
clouds. Still a ways to go to realize current forecast
highs...but with The Breaks in clouds and long days this time of
year...will leave alone for now and see how things pan out in a
few more hours and make any necessary changes.


Previous discussion...

Short through Friday

Current surface analysis shows the low pressure center now across
far southeast Montana...with a cold front extending across central
Wyoming and into Colorado. A tight pressure gradient /around 25 mb
across South Dakota/ has set up ahead of this system. Winds will
gradually decrease as the cold front approaches...then switch
around to the northwest behind the front. However...until this
happens...strong and gusty southeast winds are anticipated across
the the County Warning Area. BUFKIT soundings show up to 40 kts at the top of the
mixed layer across eastern South Dakota. Showers have also been
able to pull some the winds to the surface...kmbg gusted to 48 miles per hour
with a brief shower last night. A Wind Advisory has been issued to
account for these strong winds. The main area of precipitation is
coincident with modest 700 mb frontogenesis over the northeast County Warning Area
this morning. Additional scattered shower development is ongoing
further west however. Drier air is expected to move into the
central County Warning Area this trended probability of precipitation down across this
region early in the afternoon...whereas precipitation across the
northeast should continue into the afternoon hours. Additional
development is then possible from west to east across the County Warning Area as
the cold front passes over the region.

Perhaps some lingering rain showers will continue across the far
northeast into Thursday morning...but otherwise northwest winds
should transport cooler and drier air into the region. If the
forecast of gusty northwest winds and min relative humidity values below 20
percent across the western half of the County Warning Area flag
warnings may again be needed Thursday afternoon. Also...given
steep low level lapse rates Thursday and Friday...peak heating
shower development is not out of the question across the northern
County Warning Area. However for now just went with a dry forecast.

Long term...Friday night through Tuesday

The latest models have trended toward a common solution for the
middle level flow pattern/evolution over the central Continental U.S.. strong
trough will enter the California coast early in the weekend and then
cross the central/southern rockies and emerge into the plains
late Sunday. At that point the pattern starts to turn very blocky
and leads to most models cutting off a low over the Central
Plains. Per various uvm forecasts/tropopause map it appears a fair amount
of energy will rotate around that developing upper low and move
across the abr County Warning Area Sunday and Sunday night. Thus those two periods
should see the best opportunity for widespread precipitation. As for thing stands out vs previous model runs. All
models have trended warmer...especially the European model (ecmwf) early in the
period. Thus have raised temperatures a bit for Saturday and
Sunday although have some reservations about Sunday if precipitation is
indeed as wide spread as models allude to.


12z tafs for the kabr...Katy...kpir and kmbg terminals

Strong southeast breezes and scattered showers are expected across the
region this morning. For this afternoon an approaching front
continue spark more showers and even some thunderstorms over the
area into the evening hours. Meanwhile areas of MVFR ceilings are
expected over mainly eastern parts of the region this afternoon
and evening.


Abr watches/warnings/advisories...
South Dakota...Fire Weather Watch from Thursday afternoon through Thursday
evening for lower bad river-Missouri Coteau-upper Cheyenne-
upper James River-upper Missouri Coteau.

Wind Advisory until 1 PM CDT this afternoon for Campbell-Potter-

Wind Advisory until 7 PM CDT this evening for Clark-Codington-

Wind Advisory until 4 PM CDT this afternoon for Brown-Buffalo-

Minnesota...Wind Advisory until 7 PM CDT this evening for Big Stone-traverse.


short term...serr