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Area forecast discussion 
National Weather Service Grand Forks ND
1139 PM CDT Sat may 23 2015

issued at 1139 PM CDT Sat may 23 2015

No changes for this update.

Update issued at 943 PM CDT Sat may 23 2015

Adjusted the clouds a bit more as cirrus and even some middle level
clouds continue to move in from the south. Will continue to keep
lows in the 40s to low 50s.

Update issued at 648 PM CDT Sat may 23 2015

Made a few minor tweaks to clouds to fit current satellite trends
but no changes otherwise to the going forecast.


Short term...(this evening through Sunday night)
issued at 323 PM CDT Sat may 23 2015

Main trend is slower...and modified the pop/weather forecast
accordingly. Anticipate increasing clouds tonight which should
keep the temperatures from dropping too much (except possibly near
the international border). Upper ridging hangs on into Sunday
(even Sunday night) which will keep most areas dry until Sunday
night. Did keep scattered showers on Sunday along and south of
I-94...but even this might be overkill.

Long term...(monday through saturday)
issued at 323 PM CDT Sat may 23 2015

Monday-Tuesday...focus will be on an upper level wave that is
currently rounding the base of The Rockies upper low. This feature
will propagate northward Sunday night with a strong middle-level low
developing. The NAM/sref indicate more interaction with The
Rockies upper low than the ECMWF/GFS. This will affect location of
the heavier rain amounts. At any rate...anticipate a heavier
deformation rain band to set up somewhere across the forecast area (nam/sref
further north than the ECMWF/gfs). With precipitable waters 1.25 to 1.50
inches and strong forcing...operational models and ensemble
guidance all suggest an area of 1-2 inches rainfall...with
isolated amounts up to 4 inches (much like last weekend). We have
had a week to dry out...and this rainfall expected to occur over a
12-24 hour areal flooding only a minor concern.

Drier on Tuesday...with possible weak afternoon convection.

Tuesday night-Saturday...region will be on southern edge of broad
cyclonic flow over Canada. Initially weak surface boundary across
S mb into Ontario will sag slowly south. Airmass modestly warm and
unstable south of boundary so low probability of precipitation seem reasonable. More
significant surface low associated with another western trough
will track across the Central Plains midweek with the favored precipitation
chances across the southern 2/3rds of the forecast area. Surface high
dropping south out of Canada will shunt main precipitation chances south of
the forecast area towards end of work week but will also bring cooler air
into the region. Temperatures initially will range above average
dropping to at or below averages by end week.


Aviation...(for the 06z tafs through 06z Sunday night)
issued at 1139 PM CDT Sat may 23 2015

VFR conditions continue as high clouds continue to move into the
area. Think some lower ceilings of around 5000 feet will begin to move
into the kfar area by morning...and the taf sites further north by
afternoon but conditions will remain VFR. There has been a slowing
trend for precipitation moving did not start any vcsh at kfar
until after 00z Monday. Light and variable winds will pick up out
of the east at around 8 to 10 kts.


Fgf watches/warnings/advisories...



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