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Area forecast discussion 
National Weather Service Hastings NE
525 am CST Friday Nov 28 2014

Short term...(today and tonight)
issued at 344 am CST Friday Nov 28 2014

An uneventful 24 hours appears to be in store for the local area as
winds will shift and become westerly this afternoon behind a passing
warm front...with a very relaxed pressure gradient in place across
the region. As a result...after a seasonably chilly start to the
day...a beautiful late fall afternoon is expected...with light winds
and temperatures climbing into the lower 60s across much of the
local forecast area. While there will be some passing high clouds
over the top of the upper level ridge centered across The not anticipate this cloud cover to be thick enough to
have an appreciable effect on did not make any
significant changes to inherited forecast this morning.

With mostly clear skies and light winds continuing overnight
tonight...expect temperatures to drop quickly after sunset. That
said...overnight temperatures will likely remain a few degrees
warmer than this mornings readings as the local airmass will have
modified some thanks in part to the light southwesterly winds this
afternoon advecting in a more moist and warm airmass.

Long term...(saturday through thursday)
issued at 344 am CST Friday Nov 28 2014

By far the biggest story during this 6-day period is another ride
on the temperature roller coaster: strap yourself in for
near-record breaking warmth on Saturday...followed by a big
Arctic plunge for Sunday (high temperatures roughly 40 degrees colder
than Saturday!). while the cold air remains in place for Monday to
kick off December...the Tuesday-Thursday time frame then looks to
feature a modest warm-up back to near or even slightly above
average values with highs mainly in the 40s.

Precip-wise...have left the official forecast completely void of
anything at this time...and for the majority of these 6 days
confidence is high in that proposition. However...the main
periods that bear watching for future forecasts possibly
introducing something are:

1) late Saturday night into Sunday night when there could be a
low probability of flurries or even a few spits of freezing
drizzle behind the Arctic front...but confidence in occurrence is
still too low for any mention at this 4th-6th period time frame.

2) at the very end of the 7-day forecast Wednesday night-Thursday...may
have to keep an eye on mainly southeast zones for some drizzle or
light rain potential...but this is a long way out and plenty
subject to change.

As for weather elements worthy of inclusion in the hazardous
weather outlook product (hwogid)...there are currently none
meeting mentionable thresholds but a few things Worth noting:
starting with Saturday afternoon...fortunately winds should be
light enough to preclude significant fire danger (despite critical
relative humidity values especially in western counties). Then
late Saturday night into Sunday...sustained winds/gusts could at
least briefly breach 30 miles per hour/45 miles per hour respectively behind the surging
cold front...and although forecast speeds are on an upward trend
the current forecast still falls a little short of this. Then
Sunday night-Monday morning...while much of the County Warning Area is forecast to
see at least slightly sub-zero wind chills...they still appear to
fall well short of advisory criteria of -20.

Now taking a look at things in more detail in 24-48 hour blocks:

Saturday daytime-Saturday night...although parts of mainly the
southwestern County Warning Area could get almost as warm today as on
Saturday...for the majority of our 30-County domain Saturday
should be The Crown jewel of late-November warmth. That being
said...confidence in temperatures is still a little shaky for only being
3rd period...due in part to models such as the NAM being strangely
hesitant to warm up especially our northeastern quadrant...likely
a result of some model errors in mixing height calculations.
Stepping back and taking a look at the synoptic big picture
aloft...this 24 hours features broad quasi-zonal flow aloft...but
with all eyes to the northwest as a sharp/positively- tilted
shortwave trough migrates from a central position over northwest
Washington state at sunrise an axis through the
northern rockies/plains by sunrise Sunday. Meanwhile at the
surface...reasonably light west-southwest breezes between 5-15 miles per hour
should define the daylight hours locally...well in advance of the
strong Arctic front diving southward through the Dakotas. With 850
millibar temperatures prognosticated to average between +14-18c during the
day and skies expected to average mostly clear...the stage is set
for at least near-record breaking warmth (see climate section
below for Grand Island/Hastings details). However...even the GFS
model is hesitant to push daytime mixing any higher than 900mb
across the area...which is really the only thing holding back the
potential for readings even warmer than currently forecast. Opted
to make only minor tweaks to highs...aiming most of the County Warning Area into
the 66-70 range...or roughly 25 degrees above normal/average for
the date. Getting past nightfall...Sat evening still looks
pleasant as latest consensus of the NAM/GFS/ECMWF are fairly
consistent in bringing the cold front to the doorstep of the
northern County Warning Area by midnight. Then Post-midnight...this front charges
south across the County Warning Area...bolstered by decent 3-hour pressure rises
on the order of 5-8mb per the 06z NAM. Forecast wind speeds for
late Sat night into Sunday were raised 5-10 miles per hour versus previous
forecast...but likely still not far this kind of setup
situation often supports at least a brief period of 30+ miles per hour
sustained/45+ miles per hour gusts. Obviously temperatures will steadily fall behind
the boundary...and have Sunday morning low temperatures well down into
the 20s most areas. least for now this front
appears to lack potential for much of the middle levels
remain dry and although models such as the NAM bring a low stratus
deck southward across most of the County Warning Area late in the night...the
depth of saturation appears to fall short of the roughly 1km
generally needed for light freezing drizzle. Of course...this
bears watching.

Sunday daytime-Sunday night...needless to say the warmth of
Saturday is a distant memory. In the middle-upper levels...the
shortwave trough responsible for driving the cold air southward is
reinforced by another wave dropping southeastward out of
Canada...with The Heart of this system reaching the upper Great
Lakes by sunrise Monday. Meanwhile at the surface...a strong cold
high pressure system on the order of 1043mb will shift eastward
into the Dakotas with time. Focusing first on the daytime will be a rude slap for those venturing out as
sustained northerly winds of at least 20-25 miles per hour and higher gusts
will persist all day...with steady cold air advection bringing
850mb temperatures down into at least the -5 to -13c range across the
area. At the surface...the net result is that highs should rise
only slightly above overnight lows. Compared to previous
forecast...highs were lowered an average of 1-3 degrees in Nebraska
zones and 3-4 degrees in Kansas zones...with the net result being a
range from low-middle 20s north to low 30s south. As already
mentioned...suppose a few flurries cannot be ruled out at some
point during these 24 hours but with low-level saturation quickly
decreasing during the day and with the primary ribbon of middle level
saturation/lift focused over northern/western Nebraska...opted to keep
the forecast "clean" at least for now. On Sunday night wind
speeds will decrease into the 10-15 miles per hour range but still remain
strong enough to preclude a major temperature plunge and only made a
minor downward tweak to previous forecast lows...aiming most areas
between 8-12 degrees.

Monday daytime-Monday night...below average cold remains in place.
Aloft...quasi-zonal flow prevails while at the surface the center
of the cold high translates eastward from the Dakotas toward the
Great Lakes...never really setting up over the local area. As a
result...the day will feature fairly light breezes transitioning
from northerly to southerly...with steadier south winds firmly
established for Monday night in the return flow regime. Made very
little change to highs/lows...with highs mainly in the 25-30 range
and lows mainly in the teens.

Tuesday daytime-Wednesday night...confidence remains reasonably
high in these 48 hours remaining dry with a decent warming trend
(although nothing like that in the shorter term). For Tuesday-
Tuesday night...the day features warming southwesterly breezes before
a fairly weak cold front drops into the area Tuesday night in
response to another shortwave trough passing eastward across the
northern plains/Great Lakes. At least for now though...this only
appears to be a weak glancing blow of colder air...with southerly
breezes established again by later Wednesday. As for
temperatures...Tuesday is currently aimed 10-15 degrees warmer than
Monday with mainly upper 30s-middle 40s...and while Wednesday highs
are currently aimed even a bit warmer than this with low-middle 40s
most all areas...that might be iffy depending on how strong that
glancing blow of colder air is.

Thursday ... the European model (ecmwf)/GFS agree on continued flat /quasi-
zonal flow over the Central Plains...although the GFS has more in
the way of a weak disturbance crossing the area. While the
forecast remains dry...both models suggest a corridor of light
precipitation (maybe only drizzle) could lift up out of eastern Kansas toward
IA/MO...potentially coming close to affecting our eastern zones.
Temp-wise...highs are very preliminarily aimed into the 40s most
areas...with near-50 Kansas zones.


Aviation...(for the 12z kgri/kear tafs through 12z Saturday morning)
issued at 458 am CST Friday Nov 28 2014

Vrf conditions are expected at both terminals for the next 24
hours...with generally light southwesterly winds and passing high
level clouds expected from time to time as an area of surface of
high pressure tracks eastward across the region.


issued at 344 am CST Friday Nov 28 2014

You gotta Love the Central Plains in the late fall...less than 2
weeks ago we were talking record cold and now we are looking at
possibly threatening record warm highs for Saturday. Today will be
plenty mild as well...but records at our primary climate record
sites (grand island/Hastings airports) appear safer...

Here is a quick rundown of record highs for today and
Saturday...along with current forecast values:

Grand island:
today: record 67 in 1986 (current forecast 60)
saturday: record 71 in 1932 (current forecast 67)

today: record 70 in 1932 (current forecast 63)
saturday: record 68 in 2003 (current forecast 67)


Gid watches/warnings/advisories...


Short term...Rossi
long term...pfannkuch

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