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Area forecast discussion 
National Weather Service Grand Forks ND
343 am CDT Sat Aug 30 2014

Short term...(today through sunday)
issued at 343 am CDT Sat Aug 30 2014

Precipitation timing tonight and Sunday will be the main forecast
problem for the short term.

Today will be fairly quiet between systems as the shortwave that
brought the cold front moves off into WI and the next shortwave
heads into Montana. The weak surface high over the region weakens further
and moves off to the east as a trough develops over the northern
rockies. Some clouds may linger in the southeastern counties as
the surface low slowly pulls further away...but the northwestern
counties should be pretty sunny. Continued to keep highs getting
into the 70s...although will have to watch the southeast if the
clouds do not clear out as much as expected it could be a bit
cooler.

Tonight...the next shortwave will come off the main trough and
into the northern plains...with a surface low beginning to enter the
western County Warning Area. There seems to be a bit slower trend with the precipitation
arriving in our western counties...with most of the activity after
06z and may even be closer to 12z. Went a bit slower with probability of precipitation but
continued to keep likely values coming into our far west by late
tonight. Increasing clouds and south wind will keep temperatures in the
50s to low 60s. The main upper trough begins to move into the
Western Plains Sunday...with the models all in fairly decent
agreement on taking the surface low northeastward into Canada. There
is less model agreement on how much storms develop along a weak
frontal boundary that moves into our eastern counties by
afternoon. Models show some cape values over 2000 j/kg by
afternoon ahead of the front...and with the fairly strong flow
aloft...shear will be good enough for severe storms. However...if
clouds hang around a bit more than expected into Sunday afternoon
the instability will be quite a bit lower. Will mention
possibility of severe in severe weather potential statement but will keep it out of grids for
now. Highs on Sunday should again by in the 70s.

Long term...(sunday night through friday)
issued at 343 am CDT Sat Aug 30 2014

Sunday night through Monday night...the upper trough axis moves
off to the east...but a broad trough remains over the region into
the early part of the work week. The surface trough will move off to
the east leaving the County Warning Area in southwest to west winds. Showers and
thunderstorms will linger in the eastern tier through Sunday
night and even into Monday in the Lake of The Woods area. Some
additional precipitation development is not out of the question into
Monday night as a models show weak shortwaves embedded in the main
trough although they cannot agree on exact placement. Will
continue to keep low probability of precipitation going for Monday night. Temperatures will be
just slightly below seasonal averages.

Tuesday through Friday...this particular run of the various models
are in fair agreement through this period. A flat northwest flow
early quickly transitions to a flat southwest flow Thursday as
moderately strong 500mb short wave moves into Pacific northwest. Thunderstorms and rain/rash near intnl
border early in period along baroclinic ribbon and upper divergence
under exit region of lifting jet. Temperatures should warm to near
early September values Tuesday and Wednesday.

The European model (ecmwf) [low-res] and Gem-New Hampshire are about 12-18hrs faster than the
GFS with frontal passage. Ec/Gem have the wind shift moving across the County warning forecast area
early Thursday while GFS has it exiting eastern County warning forecast area 00z Friday. Dgex
is even faster with surface high squarely over County warning forecast area 00z Friday...so have
discounted that model beyond 00z Thursday. If slower model solutions are
correct high temperatures Thursday could be well above median values.

With departing jet/right rear entrance region...cooling aloft and
different vorticity like the idea of low probability of precipitation into Friday. Temperatures
drop back to or below normal at the end of the period.

&&

Aviation...(for the 06z tafs through 06z Saturday night)
issued at 1140 PM CDT Friday Aug 29 2014

Initial issue will be timing of clearing of the IFR/MVFR clouds at
Fargo and Bemidji taf sites. Clearing making its way into tvf/gfk
sites at this time and will be scattered-broken at times 06z-10z period. Went a bit
more pessimistic at Fargo-Bemidji and kept in MVFR ceilings at Fargo
until just past daybreak and kept IFR at Bemidji until past daybreak
as well as cool north winds move into the moist airmass and main
drying stays further north and west of this region. Otherwise



&&

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

$$

Short term...Jr
long term...Jr/ewens
aviation...Riddle

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