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Area forecast discussion 
National Weather Service Hastings NE
630 PM CDT sun Jul 27 2014

Short term...(this evening through monday)
issued at 404 PM CDT sun Jul 27 2014

The forecast is dry through the short term therefore the main focus
is on temperatures. The pattern aloft featured northwest flow across the
interior Continental U.S. While an upper ridge axis was building over The
Rockies and an upper trough was translating southeast through the Great Lakes
region. At the surface...high pressure was building southeast from the
western Dakotas and a cooler...drier airmass was in place with afternoon
temperatures averaging in the 80s with dps in the 50s.

The upper trough to the east will deepen tonight/Monday with cooler
air backing into our region and 850 mb temperatures drop another degree or
two. Under the influence of the surface ridge tonight and the dry air
in place...lows are expected to drop to the 55 to 60 degree range
which will be about five degrees below seasonal normals.

Heading into late tonight or early Monday...models indicate an
increase in middle level moisture/clouds and the presence of middle level
frontogenesis. Have just increased sky grids at this time with moisture
lacking in the low levels. For the start of the workweek...the surface
ridge will builds along the Missouri River and winds will be fairly
light during the day. Afternoon highs will again be similar to
today with readings in the low/middle 80s.

Long term...(monday night through sunday)
issued at 404 PM CDT sun Jul 27 2014

For those who preferred todays weather over the hot/sultry
conditions that peaked back on Friday-Saturday...then this 6-day
long term period is for you. In a nutshell...there are currently
no 90+ degree highs forecast anywhere in the County Warning Area during this
time...with most days prognosticated to generally range from low-middle 80s
north to middle-upper 80s south. Overnight lows are mainly aimed into
the low-middle 60s most nights...with some upper 50s likely
especially in northern zones early in the week. The net-result
temperature-wise is this 6-day period should generally average around 5
degrees below normal/average...essentially sealing what will
likely be a top-10 coolest July on record for much of the County Warning Area. For
example...with several days left to go to drag the average monthly
temperature down a bit more...Grand Island Airport is already
sitting on its 17th-coolest July on record out of 119 years.
Adding to the good news for those not a fan of oppressive
dewpoints/humidity...dewpoints are forecast to only average in the
middle-50s to low-60s range...which is pretty darn comfortable by
late-July/early-August standards.

As usual...confidence is a bit higher in the temperature situation
than rainfall chances. The bottom line here is that there are a
smattering of mainly low-end 20-30 probability of precipitation within various portions of
the outlook area between Tuesday morning and Friday...with the
overall-highest (if you want to call it that) concentration of
30-40 probability of precipitation within north central Kansas zones during the Tuesday
afternoon-Wednesday afternoon time frame. At least for now...the
upcoming weekend is void of any precip-mention...but this may be
no guarantee to stay this way for all areas...as Friday night-Saturday
may eventually warrant some slight probability of precipitation per some models. On a
positive note...several models agree that convective instability
will be quite meager for this time of year...making strong storms
unlikely this entire time...let alone severe storms...barring
substantive changes. On a somewhat negative note...with the
majority of the County Warning Area (especially north of the state line
area) likely struggling to see rainfall totals in excess of one-
quarter inch through next weekend...what has already been a well-
below normal month of precipitation for most of the County Warning Area will
likely persist into early August. Although far from slipping back
into a serious drought situation in the near-term...the obvious
impacts of the surplus of June moisture continues to slowly fade
away.

Before taking things in 12-24 hour blocks and adding some
meteorological detail: the most basic theme though of this 6-day
period is a prevailing eastern Continental U.S. Trough/western Continental U.S. Ridge
pattern.

Monday night...already right off The Bat here there is some
forecast uncertainty...as although confidence is high in dry
weather through the evening hours...the later night hours could be
trending toward realizing some spotty shower activity with maybe
even a weak rumble of thunder. Given that the previous forecast
was void of any rain mention...opted to take a middle-ground
approach for now and add a generic slight chance of sprinkles
County Warning Area-wide for later in the night...and defer to later forecasts to
see if a measurable pop might be warranted. In the middle-upper
levels...the local area lies along the interface between a western
Continental U.S. Ridge centered over the southern rockies and an expansive
trough that envelopes much of the eastern Continental U.S. From an anchoring
closed low centered near the southern tip of Hudson Bay. The key
for any spotty precipitation will be a zone of somewhat-subtle middle level
isentropic lift such as evident around 700 millibars and also the
310k isentropic surface. Model-wise...quantitative precipitation forecast fields from the 18z
NAM/12z European model (ecmwf) and also simulated reflectivity from the 12z 4km
WRF-nmm certainly support the trend toward some spotty shower
potential late Monday night...while the 12z GFS remained dry. At
the surface...light generally easterly breezes will setup during
the night. Temp-wise...despite increasing middle level clouds
late...should see a decent cool-down and make little change aiming
from middle-upper 50s northeast to low 60s southwest.

Tuesday daytime-night...very little change in the large-scale
pattern as northwesterly flow aloft persists between the
aforementioned mean ridge and trough positions. Even if we manage
to get through sunrise without any spotty precipitation...there is
certainly support for at least slight probability of precipitation on Tuesday morning in
most areas as a continuation of the isentropic lift signal...and
for 20-30 probability of precipitation in mainly just the southwest half of the County Warning Area during
the afternoon although the bulk of this potential activity should
focus farther west over the High Plains. On Tuesday night...kept
20-30 probability of precipitation within mainly the southwest 2/3 of the County Warning Area mainly to
account for the possibility of activity to the west during the
afternoon sliding eastward...but trended down these probability of precipitation about 10
percent from previous. Breezes generally only 5-10 miles per hour from the
southeast.

Wednesday daytime-night...pretty much status quo northwesterly
flow in the large scale over the Central Plains. The combo of low
level upslope flow interacting with low amplitude shortwave
disturbances aloft will keep considerably higher precipitation chances
going along an axis from Colorado through western into southern
Kansas...leaving the local area mainly along the far
northern/northeastern fringes of this rain potential...meaning
there is plenty of uncertainty about how much gets in...but with
the best chances focused in our north central Kansas zones. Toned down
probability of precipitation about 10 percent from previous forecast...but still left a
decent coverage of 30-40 probability of precipitation in the far south during the day and
a bit lower at night.

Thursday daytime-night...again status quo northwesterly flow.
Although models are looking mainly dry all areas...maintained some
very low-confidence slight probability of precipitation in southern zones during the day
and eastern zones at night.

Friday daytime-night...the Central Plains remains sandwiched
between the mean ridge west and mean trough east. Mainly per the
GFS allowed some slight probability of precipitation to persist for at least one more
forecast cycle in eastern zones during the day. At night...left
dry despite the GFS quantitative precipitation forecast suggesting probability of precipitation may need added at a later
time.

Saturday daytime-Sunday daytime...at least for now have kept any
rain chances out of the forecast...but there are hints that at
least southern zones may eventually need slight probability of precipitation considered
for Saturday. Certainly plenty of time for likely alterations
here. Otherwise...the same large-scale pattern that defines the
whole week generally remains in place...hence resulting in the
remarkably consistent temperatures forecast throughout this entire
6-day period.

&&

Aviation...(for the 00z tafs through 00z Monday evening)
issued at 630 PM CDT sun Jul 27 2014

VFR conditions to continue through the next 24 hours.

Occasional cloud cover will be possible at both taf sites through
the next 24 hours...but nothing below 8000ft above ground level is currently
expected. A northwest surface wind...sustained at around
12kts...will become light and variable tonight into Monday
morning. The surface wind will then become established from the
north/northeast...sustained at around 07kts...by Monday afternoon.
Visibility restriction is not expected at either taf site through
the next 24 hours.

&&

Gid watches/warnings/advisories...
NE...none.
Kansas...none.
&&

$$

Short term...Fay
long term...pfannkuch
aviation...Bryant

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