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Area forecast discussion 
National Weather Service Grand Forks ND
925 am CDT Friday Aug 1 2014

Update...
issued at 925 am CDT Friday Aug 1 2014

We will remove all mention of afternoon showers/storms in the
southeast...given weak instability/forcing and all mesoscale
models have it dry. Otherwise...the forecast for today is in good
shape with no other changes planned.

&&

Short term...(today through saturday)
issued at 320 am CDT Friday Aug 1 2014

Forecast challenge concern mainly temperatures and low end precipitation
chances. Models in fair agreement and will use blend for forecast.

Region to remain in middle level northwest flow through the period.

Weak high pressure will continue across the forecast area today. Surface
heating will result in weak instability this afternoon. Far southeast forecast area
on northern fringe of greater instability/cape across S/central Minnesota.
Precipitable water values remain below an inch and low level forcing
very weak along with shear. Cannot rule out potential of an isolated T
however at this point will keep forecast dry. Little change in
thermal profile so temperatures should be pretty close to
yesterday.

Friday night overall quiet and consistent with previous nights
with light winds...sky clear and relatively low dewpoints.

Saturday a weak frontal boundary will drop through the forecast area. Modest
instability and cape will exist although shear fairly weak and
best upper support will be to the north-NE in Canada. Low level
moisture flux also weak with dewpoints remaining in the 50s. For
this will stay the course with current low end probability of precipitation. Column warms
slightly ahead of boundary so temperatures may be a few degrees
warmer ahead of boundary.

Long term...(saturday night through thursday)
issued at 320 am CDT Friday Aug 1 2014

Boundary becomes quasi stationary across the forecast area Saturday night into
Sunday. With convective parameters overall weak and lack of
forcing and low level jet confidence not high in any precipitation
continuing much after sunset and more diurnal in nature. With boundary
in vicinity will however keep low probability of precipitation going. Temperatures Sunday
will hinge on degree of cloud cover.

Next more significant wave begins to round ridge to our west with
low pressure becoming better organized from Central Plains into
the northern High Plains. This will shift precipitation potential to our
western forecast area if at all and did lower probability of precipitation across the NE forecast area.

Monday through Thursday...broad northwest flow transitions to a
split pattern later in this period. Early on there is fair model
consensus with the system moving through the plains. This results in
a band of rash/tsra...with the best chances across the south half of
the County warning forecast area. A series of short waves will transverse the plains next
week....but should focus best rain chances south of our area. At
this point the GFS continues to be the wetter and farther north
while the Gem/dgex/ECMWF places most of the precipitation south of the
County warning forecast area. Consensus of models suggest low end probability of precipitation over the southern
third County warning forecast area through the later periods. Temperatures should be on the
cooler side of seasonal normal.

&&

Aviation...(for the 12z tafs through 12z Saturday morning)
issued at 640 am CDT Friday Aug 1 2014

Isolated T continues south of a bji-far line. Otherwise VFR with no
ceilings anticipated.

&&

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

$$

Update...dk
short term...voelker
long term...ewens/voelker
aviation...voelker

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