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Area forecast discussion 
National Weather Service Grand Forks ND
1138 PM CDT Friday Aug 28 2015

issued at 1138 PM CDT Friday Aug 28 2015

A few cells have developed northwest of kinl...but these should
still stay just east of the forecast area. Will continue to watch to see if
any further westward development occurs. Most of the high
resolution output keeps it just to the east. Otherwise already
seeing some patchy fog across the northern forecast area where winds have
been lightest. Will expand the mention of patchy fog to all areas


Short term...(this evening through Saturday night)
issued at 304 PM CDT Friday Aug 28 2015

Water vapor shows the main short wave over northwest Ontario moving
toward Lake Superior. Upstream in southern Manitoba are some other
weaker short waves. A few other weaker short waves also into south
central North Dakota. So pattern is pretty muddled aloft. At the
surface not much better. Short range models keep indicating a surface
trough advancing into the northern Red River this afternoon and then sinking south
this late aftn/eve. So far real hard to pick one out. Winds are
south-southwest to 25 kts Grand Forks-Grafton and do shift a tad
more west Langdon-Devils Lake region and then in southern Manitoba
pretty light and variable. So at this point hard to tell if indeed
a wind shift line will advance south as hrrr/rap/NAM and NCEP
models say. Pretty unstable in northern eastern ND/northwest Minnesota with maximum mu convective available potential energy
in the 4000 j/kg range near Roseau-Hallock...likely impacted by
higher dew points noted by awos's. That said convective models
continue to indicate some development along a weak boundary
Jamestown-Fargo-Bemidji-Park Rapids area 00z-03z period. Also
development will continue over Lake of The Woods. More uncertain
in the northern valley and far northwest Minnesota where instability maximum is as
convective short range models show nothing to develop but observation may
indicate atmosphere primed. So will continue to watch and have
probability of precipitation in areas as short range models indicate but albeit a bit
wider area. Into Saturday the heat and humidity is on as upper
ridge builds in.

Long term...(sunday through friday)
issued at 304 PM CDT Friday Aug 28 2015

Hot and humid and a bit breezy on Sunday. Next front due to move
through late Sun night into Monday with a risk of a few

For Monday night through Friday...
the trend for this period is generally warm and unsettled. The
period starts off with southwest flow aloft over the region and a
weak short wave moving through the area Monday night. Weak waves
will continue to affect the area through much of the week...with a
warm/hot air mass in place and occasional thunderstorm chances.
Middle 80s to low 90s will be common...with some middle 90s possible as
well. Toward the end of the upper level trough/low will
deepen over the western states...with a surface low likely
developing in the northern plains. The GFS and European model (ecmwf) differ on
details...including the location of the cooler air...but both have
a surface low in the general region.


Aviation...(for the 06z tafs through 06z Saturday night)
issued at 1138 PM CDT Friday Aug 28 2015

Previous set of tafs still looking good. Light or light south
winds tonight will make for some patchy morning fog. Then the
south winds will pick up again by middle to late Sat morning. Only
expecting scattered-broken cirrus/smoke for the taf period.


Fgf watches/warnings/advisories...


short term...Riddle
long term...knutsvig/Riddle

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