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Area forecast discussion 
National Weather Service Grand Forks ND
334 am CDT Thursday Aug 21 2014

Short term...(today through friday)
issued at 325 am CDT Thursday Aug 21 2014

Not unexpected scenario early this morning. One aera of
thunderstorms from northern South Dakota/scntrl ND moving east meeting with up
aera of storms forming in 850 mb low level jet. Focus of main
rains has shifted a bit south into the Richer 850 Theta-E airmass.
Also got a narrow axis of rainfall more along the upper trough
from north central ND into Manitoba. This is lifting north. In
between from Devils Lake to Hallock south to Grand Forks nothing.
So what happens today past 12z. Not clear cut. Went along with
weather forecast office dlh thinking in that rain showers will continue to expand
northeast and may increase again in coverage this afternoon in far
eastern forecast area as deeper 850 mb moisture moves north ahead of
weak surface low which will move from central South Dakota into southeastern
ND to near Detroit Lakes by 18z. As surface low moves northeast the
rest of the area may well see some scattered precipitation...especially north
and east of surface low. Least chance in SW forecast area.

Main precipitation area lifts northeast out of the forecast area tonight into
Friday. North-northeast winds behind surface low to likely aid in
cooling area down and also considerable cloud cover will not help.
Used superblend for temperatures and seems reasonable with mostly 60s dvl
basin Friday to 70s south and east.




Long term...(friday night through wednesday)
issued at 325 am CDT Thursday Aug 21 2014

After Friday...models diverge with 00z European model (ecmwf) bringing up a low
pressure and considerable rain activity to much of eastern South Dakota into
northern Minnesota later Saturday into Saturday night. GFS/Gem are farther
west with the main rains over western ND into Saskatchewan/western mb. NAM in
between and faster with surface low moving through eastern ND Saturday evening
and heavy rainfall in central ND and less east. For the time being
went along with HPC thoughts which is a wetter one for west-central into
north central Minnesota later Saturday into Sat night.

Sunday-Wednesday...very low confidence through this period with
model solutions diverging early next week. For late weekend...an
upper shortwave trough will lift out of The Rockies. The position of
the surface low and greatest forcing for precipitation remains uncertain.
Thereafter...the GFS maintains southwest flow aloft with a
progressive upper trough moving across the region for
mid-week...while the European model (ecmwf) is much flatter with the flow. Temperatures are
likely to run primarily below average...but daily temperature trends will
hinge on how exactly the pattern resolves itsel

&&

Aviation...(for the 06z tafs through 06z Thursday night)
issued at 1122 PM CDT Wednesday Aug 20 2014

As the showers/thunderstorms have moved into the kdvl region they have not
resulted in any non VFR ceilings as of yet. Not looking like the
showers/thunderstorms even along and south of kjms are resulting in lower
ceilings yet. Therefore will keep tafs in the VFR range and let
later shifts lower them if any lower ceilings show up. Tried to
time the precipitation from west to east as best as possible...but the
eastward progress has been very slow. Models also disagree on how
fast to move any of this out of the area later this morning or
afternoon. Tried to use a model blend but confidence pretty low
overall.



&&

Fgf watches/warnings/advisories...
ND...none.
Minnesota...none.
&&

$$

Short term...Riddle
long term...makowski/Riddle
aviation...godon

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