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Area forecast discussion 
National Weather Service Hastings NE
1134 am CDT sun Aug 30 2015

issued at 1134 am CDT sun Aug 30 2015

Needless to say...fog/dense fog issues overnight/early this
morning were overall-worse than expected yesterday...and reached
farther west as well. Fortunately...this fog has since dissipated
over the past few hours...and per visible satellite...we are left
with a remarkably similar situation to exactly 24 hours
high-level smoke influenced hazy sunshine is widespread over
roughly the western 2/3 of the County Warning Area...while stubborn low stratus
is slowly but surely eroding from west-to-east within eastern

For the rest of today...have made little in the way of noticeable
changes to previous forecast...but because of the clouds hanging
on longer in eastern zones and holding down/delaying heating
somewhat...did shave a few degrees off afternoon highs in some
eastern counties...while leaving western areas unchanged. The net
result is highs aimed from low-80s in far eastern counties along
Highway 81...generally middle-80s central...and upper 80s/low 90s in
west/southwest zones.

Going forward through the next 24 hours...still expecting
essentially a "zero risk" of precipitation through Monday
afternoon...with the main challenge centered on whether or not yet
another round of fog and/or stratus plagues parts of the County Warning Area
tonight/early Monday. So far...signals are mixed and have not yet
introduced a formal mention of fog into the forecast. Plenty more
on this with the main afternoon discussion...stay tuned.

Update issued at 546 am CDT sun Aug 30 2015

The area of dense fog continues to slide west. Therefore...expanded
the dense fog advisory west to include Ord...Kearney...and

Update issued at 347 am CDT sun Aug 30 2015

The visibility at a few sites has fallen to one quarter mile and
expect that the fog will continue to increase in coverage with
poorer visibilities expanding as we near dawn. Consequently...have
issued a dense fog advisory for much of our forecast
area...generally east of a Greeley...Minden...Phillipsburg line.


Short term...(today and tonight)
issued at 255 am CDT sun Aug 30 2015

The primary forecast concern will center around areas of fog and
poor visibility to less than 1 mile is many locations. An upper
level ridge axis extends from the Desert Southwest northeast into
the Central Plains. The surface ridge axis has pressed off to the east
allowing for light southerly return flow. A low stratus deck over
eastern Nebraska has been expanding back to the northwest and into
central Nebraska early this morning as expected. Areas of fog were
beginning to develop as of 2 am and expect low clouds and fog will
increase in coverage through 7 am or 8 am. The fog and low stratus
will quickly burn off between 8 and 10 am as the intense late Summer
sun rises higher into the sky. The best chance of seeing more
widespread lower visibility fog and low clouds this morning will
generally be across our eastern forecast area...along and east of
Highway 281. One other thing to watch for today will be the smoke
from western wild fires. The smoke was rather thick on Saturday and
could be hanging around again today.

The upper ridge axis sitting overhead will keep our rain chances at
zero percent through at least the short term period today and
tonight. The surface wind will be just a bit stronger out of the south
at 10 to 15 miles per hour gusting to over 20 miles per hour by this afternoon. The
increasing wind will be due to a tightening pressure gradient as a
surface low swings down into the Dakotas this afternoon. Skies should be
largely cloud free by late morning through this evening...but that
smoky haze from the western wildfires could linger around the area.
Expect afternoon highs will be a few degrees warmer than yesterday
due to the increasing south winds and warm air advection. Expect
highs will range from the lower 80s eastern zones... to the middle 80s
in the Tri Cities... to around 90 over our northern Kansas counties.

Tonight...the main question will center around if the fog and low
stratus will finally stay east of our forecast area or if it will
move back in yet again. There is really not too much change in the
overall pattern as the upper ridge stays nearly stationary. The sref
indicates a fairly decent chance of fog again across our eastern
zones. However...the low level and surface wind will be just a little
stronger tonight...which might provide just enough mixing to keep US
from fogging in. Therefore...have left fog out of the forecast for
now...but would not be surprised to see some fog develop especially
in low spots. There could also be some low stratus over our eastern

Long term...(monday through saturday)
issued at 255 am CDT sun Aug 30 2015

Aloft: a longwave ridge will extend from Texas into eastern Canada through
Sat. The longwave trough will reside over the western USA. This will
result in SW flow over in the Central Plains. Progression upstream
over the Gulf of Alaska should result in height rises over the western USA
next weekend. The westerlies will remain far to the north and west of the
forecast area. So no notable qg forcing is envisioned at this time.

Surface: the Pacific cool front currently making its way through the western
USA will eject into the Dakotas and Nebraska Panhandle tonight. Its tail
end will be oriented from NE-SW across central Nebraska into western Kansas by
00z/Tue. It then dissipates Tuesday. The next Pacific front will only
advance until it becomes parallel to the upper-level flow which means it
will become stationary well north and west of the forecast area middle-late week
as several lows track NE along it. Am not expecting this front to make
it through here until next sun at the earliest. High pressure will remain
parked over the eastern USA through the forecast. So essentially the forecast area
will be in the warm sector into next weekend.

Not much to say as far as daily details. We are in a very dry
pattern and see no change in that. Opportunities for rain are
minimal and that means little in the way of adverse/hazardous weather.
Model qpfs are spotty and light with little in the way of
consistency due to weak/minimal forcing...and they are probably

High/low temperatures will average about 5f above normal.

S winds will probably become breezy Tuesday-Sat as pressure gradient increases
between the eastern USA high and the Lee-side trough.


Aviation...(for the 09z kgri/kear tafs through 09z early Monday morning)
issued at 446 am CDT sun Aug 30 2015

The primary aviation concern will continue to center around our
morning fog and low ceilings. Satellite imagery at 5 am shows low
clouds and fog across all of eastern Nebraska east of Kearney.
At 5 am kear was right on the edge of the fog and some fog will
likely slip into kear prior to dawn. IFR and even LIFR ceilings
are possible at times this morning...primarily prior to 10 am. The
visibility has been fluctuating but at times could be less than
one quarter mile. The low clouds and any fog will quickly begin to
break up by around 9 am and expect plenty of sunshine by late
morning through the rest of the day. The wind will remain out of
the south through the taf valid period.


Gid watches/warnings/advisories...


short term...wesely
long term...halblaub

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