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Area forecast discussion 
National Weather Service Grand Forks ND
1235 PM CDT Tuesday Jun 2 2015

issued at 1235 PM CDT Tuesday Jun 2 2015

Showers and a few thunderstorms continue in the northern County Warning Area and
in the southern Red River just east of the river. Think that scattered
to isolated showers will continue to be a threat for the next few
hours as a shortwave trough moves through the area. Cut highs a
few degrees in the central County Warning Area as clouds will linger in that area.
Will still keep the far southeastern tier rising to the upper that is most likely to get some sunshine. However...there
is a lot of cloud redevelopment on the leading edge of the
clearing so will keep 80s out for now and will have to watch for
destabilization. At this point it seems that storms will fire
further west over south central ND this afternoon and move east
later tonight. A pretty complex situation so will continue to
monitor during the next few hours and adjust accordingly.

Update issued at 925 am CDT Tuesday Jun 2 2015

Radar shows some weakening thunderstorms moving into the
southwestern counties...which none of the short range models have
a very good handle on. Do think that the activity will continue to
weaken as it moves east into less tried to adjust
probability of precipitation for current radar and transition it into more general chance
of thunderstorms in the next few hours. There is a decent amount
of clearing back behind the current showers in central
think we should still destabilize nicely for this afternoon and
some severe is expected.

Update issued at 640 am CDT Tuesday Jun 2 2015

Thunderstorms are weakening as expected...and gradually shifting
east/northeast. No change in thinking that this morning activity
will remain weak and dissipate. Then...

Latest rap/hrrr guidance suggests the warm front will set up
nearly the same location as the northern edge of the Storm Prediction Center slight
risk area. These models...and the 06z hopwrf...also quicker (or
further east by middle-afternoon) with the surface low/cold front. This
scenario would place the strongest storms across southeast ND.


Short term...(today through wednesday)
issued at 353 am CDT Tuesday Jun 2 2015

Severe thunderstorm potential will be the main concern. 00z models
in decent agreement and will utilize a blend of the NAM/GFS/ECMWF
along with cam guidance. Water vapor imagery indicates several
upstream shortwaves that will affect the region. Actual timing and
track of these features...and their interactions with each other
will ultimately determine how this event unfolds. Individual cams
and cam ensemble members all indicate slightly different
solutions. With that said...a general idea does emerge from all of
these solutions. The activity within the Red River valley...and
the activity across southeast ND will each slowly propagate to the east/NE
through the morning hours. Instability and deep layer shear will
decrease during this strong storms are not expected into
the early afternoon hours. A stronger upper wave approaches the
region today...developing a strong low level jet by this
afternoon. This upper wave will track across northern ND...setting
up a surface boundary across the region (which will be the northern
limit for severe potential). Although cloud cover and heating
uncertain...most guidance does support ample low level moisture to
be advected into the region along and south of this surface boundary.
With deep layer shear increasing...the ingredients for severe
potential (supercell type storms) will be in place. The most
likely area for severe potential hinges on timing of the surface low/cold
front and wherever this likely trigger is by mid-afternoon. Cam
guidance suggests this activity will weaken as it moves eastward
(using updraft helicity). Current indications are for severe
storms to develop across south central North Dakota...and move
into southeast North Dakota during the evening...but weaken toward
the Red River valley. Less intense storms...but more widespread
showers...expected across the northern forecast area.

Long term...(thursday through monday)
issued at 353 am CDT Tuesday Jun 2 2015

Thursday and Thursday night...weak Canadian high pressure moves
across the area with slightly cooler temperatures and light winds.

Friday through Monday...medium range models are in fairly high
pressure begins to move away Friday and Friday night with return
flow and warmer temperatures. upper level wave will
bring more chances for showers and storms Saturday into Sunday
across the area. The wave departs the area by Monday...with a return
to warmer and drier conditions.


Aviation...(for the 18z tafs through 18z Wednesday afternoon)
issued at 1235 PM CDT Tuesday Jun 2 2015

Tricky aviation forecast due to the lingering questions surrounding
convection later this afternoon. At this point it appears that kdvl
may be socked in with lower clouds and east-NE winds. Kgfk/ktvf
still have S-south-southeast winds but lower clouds are not that far
will tempo in some of them for the afternoon just in case. There are
also lower clouds just west of kfar. Will keep thunderstorms mentioned by
late afternoon at all taf sites...although current indications are
that they may mainly affect the kfar area and southward. Rest of the
area may see more of a shower/thunderstorm combination. However lots of as a better picture of this afternoon emerges will
updates tafs as needed. Will keep the lower clouds in for the
duration once they appear. Wind directions will also be tricky.
Kdvl/kgfk/ktvf will keep or be near the northeast winds while
kfar/kbji will stay with S-south-southeast winds much longer. By later tonight
into Wednesday the entire area should switch to the north.


Fgf watches/warnings/advisories...


long term...Hopkins

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