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Area forecast discussion 
National Weather Service Grand Forks ND
244 PM CDT Monday Apr 27 2015

Short term...(this evening through Tuesday night)
issued at 244 PM CDT Monday Apr 27 2015

Precipitation chances tonight will be the main forecast issue for the period.

Split flow aloft continues...with the northern branch shortwave
entering western ND at 19z. The shortwave will continue to
progress into the northern plains overnight...finally pushing a
weak cold front through the County Warning Area. The best radar returns match up
well with the 850-700mb frontogenesis and should begin to move
more fully into our northwestern counties by 00z. Shortrange and
global models all have the band of precipitation moving eastward across
the County Warning Area...with some weakening of the frontogenesis as well as the
q vector convergence. Will continue to keep highest probability of precipitation west
through early evening...then moving eastward and decreasing to
more scattered as the night progresses. Think that a tenth or so
of quantitative precipitation forecast will be the most our area sees...with most locations seeing
a bit less. Clearing skies and lighter winds towards morning may
allow for the formation of some patchy fog in our northwestern
counties. The temperatures will be cooler in that area and drop into the
middle 30s with 40s further east where clouds will be hanging around.

Tomorrow...a few lingering showers will be possible in our far
eastern counties early...but otherwise we should see clearing
skies and drying conditions as surface high pressure builds into the
region. Highs will be a few degrees cooler in the areas that got
into the 60s and 70s today but the northwestern tier that is
socked in today should break out and join the rest of the County Warning Area
rather than being stuck in the 50s. The clear skies and light
winds will continue into Tuesday night with most sites dipping
down into the 30s.

Long term...(wednesday through monday)
issued at 244 PM CDT Monday Apr 27 2015

Wednesday and Thursday...conditions will be very quiet for the
most part as upper ridging builds into the northern plains. Warmer
temperatures with highs in the 70s will come back as the thermal ridge
approaches and southerly winds will begin to pick up as the next
surface trough develops to our west. The models are showing some
variation with the next shortwave trough coming in late
Thursday...with the European model (ecmwf) and Gem faster and more vigorous than
the domestic models. Given the slowing trend with the early week
system am inclined towards the slower solution...but will include
some low probability of precipitation in our far northwestern counties Thursday afternoon
in case the faster models verify.

Thursday night through Monday...long term period starts off with
zonal flow pattern behind a short wave ridge over the Great
Lakes...giving a chance for some departing rainshowers in the east
early in the period. The upper pattern becomes more northwest over
the weekend. Surface high pressure should bring dry conds Friday night
into Sat...however a series of weak impulses then flow through the
northwest flow pattern and brings chances of rain showers for the latter
half of the long term. Subtle differences can be expected between
models with these minor disturbances...translating to timing
differences for any given period. Temperatures will generally be in the
70s in day and 40s at night.

&&

Aviation...(for the 18z tafs through 18z Tuesday afternoon)
issued at 1240 PM CDT Monday Apr 27 2015

Latest radar returns show a band of MVFR ceilings with some precipitation
reaching the ground just west of dvl. This is expected to shift east
this evening...however confidence for any rain over the valley is
diminshing. At this time will mention vcsh at dvl but not gfk/far.
Do expect some MVFR ceilings tonight as boundary moves through...mainly
after 03z.



&&

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

$$

Short term...Jr
long term...speicher
aviation...speicher

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