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Area forecast discussion 
National Weather Service Grand Forks ND
1149 PM CDT Sat Apr 18 2015

issued at 1149 PM CDT Sat Apr 18 2015

Rain has started in the southern County Warning Area. Will have to watch where the
dry slot ends up...but for now with the precipitation coming up from the
south and the rain along the cold front to our west...most sites
should be getting at least some rain. Tweaked probability of precipitation a bit for
current radar trends and trimmed quantitative precipitation forecast just a tad from the red
westward as short range models have been trending more eastward
with the highest amounts.

Update issued at 936 PM CDT Sat Apr 18 2015

Adjusted probability of precipitation to reflect current radar trends. Some higher returns
are entering Grant County although Elbow Lake has yet to report
rain. Think that we will continue to see rain moving in and
eventual saturation. Did slow down the northward progression as it
seems that locations north of Fargo will not see much before
midnight. Western showers still a ways from moving into the Devils
Lake basin...but should be coming in around the 04 to 05z time
frame. Made some tweaks to the quantitative precipitation forecast as the northern edge of amounts
will be light before 06z.

Update issued at 650 PM CDT Sat Apr 18 2015

Made only minor tweaks to the grids so far as the forecast seems
on track for rain coming in later tonight. The short range models
have some precipitation getting into the far southern counties around
02-03z...which seems reasonable given radar loops. Current probability of precipitation
start ramping up in the next few hours so will keep timing as it
is for now.


Short term...(this evening through Sunday night)
issued at 304 PM CDT Sat Apr 18 2015

Main forecast challenge will be the area of precipitation that will finally
move across the forecast area tonight into Sunday. Seeing a bit more cloud
cover moving northward now...but really do not see much getting
into the southern forecast area until after 00z sun. Then the models show two
distinct areas lifting into the forecast from the northwest and the other
from the south. The northwest area of precipitation will finally merge with the
southern one but the southern one will be the one that has the
higher precipitation amounts. At this point it appears that the higher precipitation
amounts will fall over southeast ND and most of the northwest
quarter of Minnesota. Still looking at amounts of 0.50 to 1.00 inches
over that area and less west of there. On Sunday the main question
is how fast the area of precipitation lifts through the forecast area. Operational models
show a little slower solution than the nam12/sref...basically
keeping steady rain over northwest Minnesota through at least 18z sun then tapering
back. Nam12/sref would have most of it over by 15z Sunday and then
much less during the day. Sunday night looks a little breezy and
temperatures also begin to drop behind the system. Looking at a little
light snow possible by late night. This could result in a light
amount of snow accumulation in grassy areas in the north and maybe
a few flakes to the south.

Long term...(monday through saturday)
issued at 304 PM CDT Sat Apr 18 2015

Still looking at some wraparound precipitation into Monday and Tuesday but
mainly across the eastern forecast area. Again temperatures cool enough at night
that light snow remains possible. Could end up with an inch or two
of light snow in the Lake of The Woods region. Otherwise winds
really crank up during the day looking at a raw day
overall. Lower winds Tuesday as high pressure tries to nose in behind
the departing low.

Tuesday night-Saturday...models in good agreement that the large
scale pattern will remain fairly amplified through the period with a
ridge to the west and an upper low to the east. This pattern will
only shift slightly east. For this region...high confidence that
the weather will be mostly dry. Below normal temperatures will
slowly warm each day to near normal by the weekend.


Aviation...(for the 06z tafs through 06z Sunday night)
issued at 1149 PM CDT Sat Apr 18 2015

Rain has started to move into the southern forecast area...and
should impact the kfar area around 06 or 07z. The rain will
continue to spread north and eastward throughout the early morning
hours. For now will keep visible over 6sm but will include some ceilings
around 1500-2500 feet for a while. Other sites will stay
VFR...depending on amounts of saturation. Showers will move into
kdvl around 06 to 07z and winds will shift to the northwest as a
cold front moves in and merges with the main system coming in from
the south. All sites should see winds coming around to the
northwest by tomorrow morning...with some gusts above 25 kts
possible. Sustained rain will end by late morning to early
afternoon but some lingering rain showers will continue to be
possible in some areas.


Fgf watches/warnings/advisories...


short term...godon
long term...godon/tg

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