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Area forecast discussion 
National Weather Service Grand Forks ND
400 am CDT Wednesday Oct 1 2014

Short term...(today through thursday)
issued at 400 am CDT Wednesday Oct 1 2014

Surface-upper low will continue to propagate north/northeast today.
Most areas will be dry in the subsidence behind this system.
However...a surface boundary (wind shift from south to west) will
interact with very weak instability east of the valley this
afternoon...with the potential for isolated showers. Much of
tonight into Thursday will be dry. The next system approaching
from the west/northwest will bring showers (isolated thunder) to
the extreme western forecast area by later Thursday afternoon.

Long term...(thursday night through tuesday)
issued at 400 am CDT Wednesday Oct 1 2014

Thursday night-Friday night...models are trending toward a slower
and stronger solution. A shortwave will propagate into the region
from the northwest Thursday night...at the same time another
upper wave propagates into the Great Lakes from the Central
Plains. All models indicate that the Great Lakes wave will act to
block the Canadian wave...thus slowing it down. The 00z European model (ecmwf) and
00z GFS have the strongest solutions...while the NAM/Gem/sref
show a similar evolution...just not quite as strong with the
synoptic features. The general idea is for an area of
precipitation to slowly move south/southeast across the
region...mainly associated with a 700mb low. The stronger solution
would bring in colder low level air...and a higher probability for
snow. Until there is more model agreement...will side on the lower
end of quantitative precipitation forecast and wind speeds...and only introduce a rain/snow mix to
the Devils Lake basin. With that said...if the European model (ecmwf)/GFS
solutions do verify we could be looking at some sort of winter
headlines...so the next few model runs will be monitored closely.
It does look windy behind this system on Friday...and increased
wind speeds.

Min temperatures Friday night will depend on cloud cover...but most
models are indicating a stronger signal for near or below freezing
temperatures.

Saturday-Tuesday...long wave trough over central Canada and the
Great Lakes shifts a little farther east over Hudson Bay by the
end of the period. Long wave pattern amplifies for the first part
of the period then deamplifies the last half of the period. Fast
flow aloft expect to be over the area through much of this
extended period. So confidence will be low in this flow pattern.

The European model (ecmwf) was faster than the GFS at the beginning of the period and
remains so through the period. Will blend GFS and European model (ecmwf) with
preference toward European model (ecmwf). Will keep yesterdays probability of precipitation for Sat night.

Temperatures were generally lowered one to four degrees for Sat,
sun, and Monday. Temperatures increased a degree or two for Tuesday compared to
yesterdays package.

&&

Aviation...(for the 06z tafs through 06z Wednesday night)
issued at 1137 PM CDT Tuesday Sep 30 2014

Widespread MVFR ceilings over most of the forecast area with the exception
of far eastern areas such as Baudette-Bemidji-Wadena where VFR ceilings
remain. Issues this forecast is affect of dry slot in clearing out the
MVFR ceilings into Fargo area overnight and possibly into tvf/gfk as
well. Then MVFR ceilings likely to spread back in as upper low/surface low
moves into southwestern Manitoba. Winds will remain strong
overnight in the 15 to 30 knots range from the south-southeast
turning southwest and then eventually closer to west Wednesday afternoon.

&&

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

$$

Short term...tg
long term...tg/hoppes
aviation...Riddle

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