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Area forecast discussion 
National Weather Service Grand Forks ND
107 PM CDT Monday Jul 6 2015

issued at 102 PM CDT Monday Jul 6 2015

Increased north to northeast surface flow across the northern
plains through midday has continued to push most of our smoke and
haze layers well into South Dakota and central Minnesota. The
cooler and fresher air should persist through the rest of the day
..though flow will start to turn back from the northwest aloft
though the late afternoon and evening. An isolated shower is
still possible this afternoon in eastern ND but coverage would be
quite low.


Short term...(today through tuesday)
issued at 250 am CDT Monday Jul 6 2015

Temperatures and Canadian Forest fire smoke (air quality) will be
the main concerns. The region will be under an upper trough
today...with a cold pool aloft. This could lead to cumulus and isolated
shower development...although model soundings indicate a rather
dry column. Did keep the isolated showers for parts of the western
forecast area. The main story for today will be cool (upper 60s to low 70s)
and breezy. High pressure moves into the region Monday
night/Tuesday...which will lead to generally quiet weather with
similar temperatures.

The National Weather Service air quality forecast guidance (airquality.Weather.Gov)
indicates thicker smoke will affect the region today (similar
density to last Friday/saturday)...and have included areas of smoke
in the forecast (through tonight). Visibility concerns will be
confined to aviation...although air quality may again be
unhealthy (especially on Tuesday with lighter winds expected).

Long term...(tuesday night through sunday)
issued at 250 am CDT Monday Jul 6 2015

Tuesday night-Wednesday night...high pressure moves off to the
east setting up weak return flow. 00z model guidance indicates a
surface boundary (extending from a Canadian system) will be somewhere
across the northern forecast area on Wednesday. Current model runs indicate
MLCAPE along this feature 500-1000 j/kg...along with 0-6km deep
layer shear around 30 knots. This environment could lead to a few
stronger storms with expected lower freezing levels...although
coverage would be minimal given weak forcing. If
evapotranspiration/pooling increases low level moisture...then
the severe threat may increase...but as of now thinking maybe one
or two storms that could approach severe limits (hail). closed low over California breaks down upper
pattern shifts to an active southwest flow. Models still look dry
for Thursday into Thursday night before precipitation chances return across the west
on Friday. Precipitable water values rise to around 1.50 inches by
Friday night into the weekend. Temperatures also look quite warm with the
ridging during this period so there could be some capping issues
to deal with at times. Currently have Sat as the warmest day with
the best short wave/chances for convection arriving Sat night and
sun. Still quite a ways out so finer details will hopefully be
worked out as the week progresses.


Aviation...(for the 18z tafs through 18z Tuesday afternoon)
issued at 102 PM CDT Monday Jul 6 2015

Smoke continues to be the main concern. The gusty north winds at 15
to 25 kts has cleared the taf sites and all have VFR conditions.
However...smoke remains over western ND and into Canada. Think that
as winds go down this evening we will see the reduced visible due to
smoke return as what is being currently mixed settles out...but
models do not have much surface smoke until after the taf period. For
now have haze/smoke returning to all taf sites but kbji this
evening...and that eastern taf site by morning. Kept conditions MVFR
as do not think it will be very thick but will be enough to reduce
visible down to the 3-5sm range.


Fgf watches/warnings/advisories...


long term...godon/tg

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