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Area forecast discussion...updated 
National Weather Service Aberdeen South Dakota
1022 am CDT Thursday Oct 2 2014

still some lingering showers across the southeastern portion of
the County Warning Area...with clearing skies across the west. Have backed off on
the timing of possible showers over the western County Warning Area this afternoon
based on latest model runs. No changes made to winds or
temperatures at this time.

Previous discussion...
short through Saturday
winds on Friday and low temperatures Saturday morning will be the
forecast challenges.

A long wave upper level trough and surface cold front currently
moving across the region will bring showers to the extreme
southeastern and eastern portion of the County Warning Area through this
afternoon. A strong upper level low pressure system currently over
eastern Alberta will bring additional chances for showers late this
afternoon in the north central portion of the County Warning Area. This system
will also bring increasing northwest winds behind the passage of a
surface cold front. Sustained winds of 20 to 30 miles per hour are possible
along the Missouri River valley behind the front. While the winds
will diminish some tonight...they should keep the environment
mixed enough to keep temperatures above freezing. Temperatures
will likely struggle to warm on Friday thanks to cold air advection. Thankfully
the precipitation the 0z model runs on the no longer expected.
Virtually all current model runs suggest dry conditions on Friday.
It will be windy with sustained winds around 30 miles per hour with gusts
exceeding 45 miles per hour. A Wind Advisory will likely be needed.

Widespread below freezing temperatures are excepted by Saturday
morning. A freeze warning is certainly possible. High temperatures
on Saturday will remain on the cool side with highs in the lower
50s in the eastern County Warning the lower the western County Warning Area.

Long term...Saturday night through Wednesday
main forecast challenge facing the extended forecast revolves around
temperatures early in the period...along with precipitation chances Sunday.

Models remain in decent agreement with overall pattern...with
northwest flow through the forecast period. Ec/GFS/Gem all show weak warm air advection
taking place during the day Saturday...with weak cold air advection taking over
Saturday night into Sunday as weak wave travels over weak surface
front/trough situated northwest-southeast over the state. Models seem to be in
OK agreement that some form of very light precipitation is possible across
the western County Warning Area associated with this wave dropping south. Superblend
populated with some slight chance probability of precipitation across the western County Warning Area during the
day Sunday...and this seemed reasonable. Otw for the remainder of
the extended...northwest flow remains in place...although it begins to
flatten by Wednesday...with minor impulses dropping southeast across
the region. Superblend sprinkled in slight chance probability of precipitation through the
forecast period. Without any well defined wave to hang probability of precipitation
on...confidence is low for next week on when/where/if precipitation will

Temperature wise...upper flow begins to flatten by the end of the forecast
period...with warm air advection becoming stronger. Inherited and latest
superblend grids show a slight warming trend toward the middle of
next week. This seems reasonable and saw no reason to change
populated grids.


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

Isolated -shra are possible in the Katy Aerodrome through 15z...but
will not have an impact on cigs/vsbys. Otw a strong cold front is
expected to sweep through the region later this afternoon. Gusty
northwest winds from 15 to 25 kts are expected behind the front. VFR
conds are expected for all terminal locations through valid
forecast period.


Abr watches/warnings/advisories...
South Dakota...none.

short term...South Dakota
long term...Hintz


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