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Area forecast discussion 
National Weather Service Grand Forks ND
631 am CDT Thursday Jul 31 2014

issued at 631 am CDT Thursday Jul 31 2014

Made a few minor tweaks to clouds...but no major changes for the
morning update.


Short term...(today through friday)
issued at 335 am CDT Thursday Jul 31 2014

Temperatures and if we get anything more than virga showers this
afternoon will be the main forecast issue.

Northwesterly flow aloft continues...with one weak shortwave
currently entering the northern County Warning Area but producing little more than
a few middle level clouds. Another weak shortwave can be seen on WV
loop along the Saskatchewan/Manitoba border. Models have this
shortwave approaching the western County Warning Area today and the NAM and a few
other runs hint at some precipitation. However...looking at model
soundings there is little moisture available in a very thin middle
level layer. Increased clouds a bit over the western forecast
area...but kept the forecast dry for the time being although some
virga is definiately possible. Think that even with more clouds
the increasing warming of the column should help temperatures get up into
the lower 80s today.

Northwesterly flow aloft and a weak surface pattern will continue
through tonight and Friday. Clouds will decrease again tonight and
temperatures should again drop into the 50s. Friday will see very similar
temperatures to today.

Long term...(friday night through wednesday)
issued at 335 am CDT Thursday Jul 31 2014

Friday night through Saturday night...hints of a pattern shift
start to occur as a weak shortwave moves down across southern
Canada and into Ontario. This should help push a frontal boundary
into the region. At this point it seems that the boundary will be
approaching our northern counties late in the day on
Saturday...moving southeastward Saturday night as the upper
shortwave begins to dig towards The Arrowhead of Minnesota. Still not
huge amounts of moisture to work with...but think there will be
enough to get some storms going along the front. Kept probability of precipitation in the
20-40 percent range through Saturday afternoon into Saturday

Sunday through Wednesday...models continue to show a slow...subtle
deamplification of the pattern this period. Models remain relatively
consistent with probability of precipitation and temperatures this period. Chance probability of precipitation
indicated throughout much of the period as ridge riding waves and

For Sunday return flow out of departing high will not result in a
significant increase in the temperature regime. For Monday and
Tuesday temperatures really do not vary much as cloud cover expected
to mitigate weak low level warm advection. Models agree that energy
moving along the baroclinic zone support probability of precipitation...and timing is all
but impossible to pin down at this time frame.

For Wednesday into Thursday a split flow develops. Along with the
upper high retrogressing some drier air infiltrates the region from
northwest to southeast. GFS holds onto inverted trough and low probability of precipitation
east of the valley Wednesday night...while dgex and European model (ecmwf) much less
bullish so will cut probability of precipitation at the end of the period.


Aviation...(for the 12z tafs through 12z Friday morning)
issued at 631 am CDT Thursday Jul 31 2014

VFR conditions will continue throughout the period as weakening high
pressure remains over the forecast area. Light and variable winds
will steady out of the northwest at around 8 kts before becoming
light and variable again this evening.


Fgf watches/warnings/advisories...


short term...Jr
long term...Jr/ewens

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