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fxus63 kfgf 192357 

Area forecast discussion
National Weather Service Grand Forks ND
657 PM CDT Thu Sep 19 2019

issued at 656 PM CDT Thu Sep 19 2019

Clear skies across the region currently, with light southeast
winds and mild temps holding on. Cloud cover should increase
ahead of initial impulse shortly before sunrise Fri when period
of morning showers/embedded storms track across the southern
valley. Further east in north central Minnesota (or far eastern cwa)
where skies will remain clear longer and radiational cooling
better we couldn't rule out shallow fog development, but there is
an inconsistent signal in guidance for this, so no mention added
to forecast at this update.


Short term...(this evening through friday)
issued at 312 PM CDT Thu Sep 19 2019

Concern tonight into the tomorrow are showers and storm
development along with temps and wind Friday. Overnight tonight
strong temp and moisture advection is expected to aid the
development of non-severe showers and storms in the predawn
hours. This activity will linger into the late morning giving way
to strong south winds and a mix of clouds and sun. This will allow
highs to reach into the low 80s as long as morning activity
deteriorates. South winds will be breezy with gusts to 25 to

Long term...(friday night through thursday)
issued at 312 PM CDT Thu Sep 19 2019

Attention late Friday afternoon into the evening turns to severe
weather potential and the threat of heavy rainfall. Models bring
instability with surface based cape into eastern ND Friday afternoon
up into the 2000 to 3000j/kg. Placement of the strongest shear
values aligns along and behind the cold front. Href updraft
helicities depict the strongest features, supercellular Mode,
across western an central ND in the afternoon and spreads eastward
slowly into the evening into the dvl Lake Basin and northern
valley. Expecting storms to reach into the central and southern
valley around or after midnight. All modes set to be possible in
the Devils Lake basin with 1" hail and 60mph wind gusts will be
the main threat in the valley. Heavy rainfall signal continues
with cips analogs and ensemble guidance indicating high end of to
2 inches in dvl basin. Widespread 0.50" to 1.5" is expected
through Saturday morning with the lower amounts in the lakes
country of Minnesota.

00z sun - 00z Mon

Upper level system is forecast to over ND Sat night. Wrap around
precip will shift out of the area Sat night and sun. Cooler with
highs in the 60s.

Mon - Thu

Split flow will be across North America with northern stream over
southern Canada and southern stream over the southern US. Long wave
trough will move across southern Canada through the period. Another
long wave trough remains over the Desert Southwest.

Flow aloft remains progressive. The GFS and the European model (ecmwf) were in good
agreement through Mon with the northern stream. The European model (ecmwf) becomes
the faster solution and more zonal than the GFS after Mon. Chance
for rain/thunder on Wed.


Aviation...(for the 00z tafs through 00z Friday evening)
issued at 656 PM CDT Thu Sep 19 2019

VFR conditions should prevail through the taf period, though
brief drops in ceilings to 2-3kft above ground level can't be ruled out where
showers/a few thunderstorms track across southeast ND into west
central Minnesota 10-14z period. Low confidence in more than showers at
kfar, so held ceilings up for now (may consider introduction of
tempo group depending on newer guidance next update cycle).
Shallow fog can't be ruled out at kbji late tonight/early Fri
morning, but again low probability event and held off on lower
category introduction.

Light southeast winds increase Friday after 12-15z as system
approaches from the west and gusts 25-30kt will be possible at
most terminals through the daytime period Friday.


Fgf watches/warnings/advisories...


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