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Area forecast discussion 
National Weather Service Grand Forks ND
350 am CDT Friday Jul 3 2015

Short term...(today through saturday)
issued at 350 am CDT Friday Jul 3 2015

Thicker smoke...causing visibility restriction 1sm-3sm...moving into
the region. National oceanic and atmospheric administration air quality forecast guidance suggests thicker
smoke for much of the area today. Lowered maximum temperatures as a
result...and extended smoke in the weather grids through the day. Hrrr
not too excited about shower/thunder potential this
afternoon...and given expected lower maximum temperatures will lower probability of precipitation to
20% across the southern forecast area.

Saturday is still looking like dry weather and warmer...although
temperatures will be dependent on the smoke...which will likely
linger until the cold front moves though Sat night/Sunday.

Long term...(saturday night through thursday)
issued at 350 am CDT Friday Jul 3 2015

Saturday night-Sunday night...convection and severe potential on
Sunday will be the main concern. 00z models still show some
differences with regards to timing of the surface boundary and
instability values (and how quickly stronger deep layer shear will
overspread the region). Most guidance suggests middle to upper 60f
dewpoint values just ahead of the surface boundary...which appears
reasonable given the time of year (evapotranspiration)...and
would lead to MLCAPE 1500-2500 j/kg. Moderate instability will
lead to a marginal risk of severe storms...but widespread stronger
(organized) storms may be limited due to weaker deep layer shear
along and ahead of the surface boundary. The main threat may be heavy
rain with precipitable waters above 1.5 inches...and storms moving parallel to
the surface boundary. More details can be analyzed once this event
gets into the cam guidance timeframe.

Monday-Thursday...upper pattern depicts cutoff low spinning close
to California coast with absence of any long wave ridging over
Continental U.S. During the extended forecast period. Guidance products in
good agreement showing region under influence of zonal flow for
next week. Departing cold front early Monday will usher in
somewhat cooler air poised to keep temperatures about 5 degrees below
average through Thursday. High pressure will give Tuesday the best
shot at a totally dry day before a short wave (timed a bit
differently by GFS/ecmwf) enters the picture Wednesday into
Thursday. Best estimate brings renewed thunderstorms and rain chances to forecast
Wednesday into the first part of Thursday.


Aviation...(for the 06z tafs through 06z Friday night)
issued at 1110 PM CDT Thursday Jul 2 2015

The main aviation concern will be smoke and lower visibilities. The main
site affected with be kdvl...and will monitor other sites. Winds
will be under 10kt with dry conditions through the period.


Fgf watches/warnings/advisories...


long term...wjb/tg

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