Area Forecast Discussion
Issued by NWS Hastings, NE

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FXUS63 KGID 242327

Area Forecast Discussion
National Weather Service Hastings NE
627 PM CDT Sat Jun 24 2017

.SHORT TERM...(This evening through Sunday night)
Issued at 428 PM CDT Sat Jun 24 2017

The main story of these next 36 hours involves the continuation of
a slightly cooler and drier-than-average airmass, by late June
standards. Precipitation-wise, while some spotty sprinkle/light
rain shower activity cannot be ruled out within especially the
southwest half or so of our coverage area (CWA) at various times
tonight into Sunday daytime, a somewhat better chance of at least
scattered measurable rain arrives for Sunday night (mainly late
Sunday night).

Taking a quick look at the current/recent local weather scene as
of 4PM: Overall, today has turned out largely according to
expectations from 12-24 hours ago except for perhaps being a
little bit breezier (especially in our northeast half) where
westerly gusts to around 25+ MPH have been common, and there might
have also been some narrow bands of sprinkles within parts of our
southwest half this afternoon, although admittedly with such dry
low levels it`s probable that many of these radar returns are
struggling to actually reach the ground as rain. In the big
picture of the mid-upper levels, water vapor satellite and short
term model data reveals northwest-flow aloft over the Central
Plains, with a shortwave tracking southeast from MN into WI. Our
possible sprinkles/very light rain bands are being generated by
mid-level lift, but with very dry low levels below hindering rain
production, as indicative of surface dewpoints that have mixed
out well down into the 30s-low 40s for much of the day. While
broad high pressure technically is the main surface feature in our
area, deep mixing has promoted the westerly breeziness this
afternoon. High temps are on track to top out 75-80 most areas,
depending on the degree of clouds versus sun.

Now looking ahead forecast-wise through these next 36 hours:

This evening/tonight: While could justify a formal small chance of
measurable precipitation, did feel inclined to introduce a broad-
brushed "slight chance of sprinkles: to especially the southwest
half of the CWA, as one round could linger into this evening
before another round of spotty precip perhaps organizes again very
late tonight into Sunday morning. Anybody that sees measurable
rain through sunrise should consider themselves very lucky,
however. Under variable cloud cover, winds will be rather
light/somewhat variable in direction tonight. It will be another
coolish night, but probably not as cool as last night, with lows
aimed from upper 40s-mid 50s in most of the CWA.

Sunday daytime:
Again, the vast majority of the CWA will probably remain rain-free
through the day. However, with continued disturbances passing by
in northwest flow aloft, and a very slight increase in low-level
moisture and resultant instability anticipated, there might
actually be a chance of some measurable afternoon showers/non-
severe thunderstorms mainly in far southwest zones. Meanwhile, at
least spotty sprinkles will remain possible farther northeast
across more of the area, but in theory more so during the morning
than the afternoon. Compared to today`s "sneaky breeziness",
confidence is high that winds Sunday will be lighter/variable in
direction area-wide. High temps were changed little and are aimed
similar to today with mainly upper 70s.

Sunday night:
Although not everybody will see rain, there are actually modest
30-40 chances for measurable rain especially later in the night as
a slightly stronger wave approaches from the northwest and
interacts with fairly weak elevated instability. While severe
storms are certainly not expected, would not be surprised to see a
few rogue lightning strikes, so have introduced some thunder
wording to go along with the previously-existing chance of rain
showers. A very gradual warming trend in overnight low temps
continues, and have them aimed mainly mid-upper 50s.

.LONG TERM...(Monday daytime through Saturday)
Issued at 428 PM CDT Sat Jun 24 2017

General overview of this 6-day period:
First off, there was very little in the way of "noticeable
changes" from the previous forecast package. This means that we
are still looking at three primary stories:

1) We will be returning to a more active and at-times stormy
weather pattern. In fact, every single one of these forecast
periods features at least a small chance (PoP) of rain somewhere
in the CWA, with the only exception currently being Tuesday
daytime which is currently a dry forecast area-wide. Of course,
not all of these chances will ultimately pan out, but as it
currently stands, some of our better chances (more like "hopes"
for many who are likely increasingly-wanting a decent rain) are
focused during the following periods: Monday daytime, Tuesday
night, Thursday afternoon-night. Again, these aren`t our only
rain chances, but they currently appear to be the overall-best
ones and carry PoPs up to 50 percent. For what it`s worth, the
default model blend used to initialize the extended forecast also
assigned some fairly decent 40-50 percent PoPs to next Saturday,
but in this forecaster`s opinion those are probably plenty
generous for being a week out and suspect they may soon be toned
down a little in subsequent forecasts.

2) Going in tandem with "1", it looks like at least "some" chance
of strong-to-severe storms will return mainly during the Tuesday
evening-Thursday night time frame. Mainly because these periods
are 3+ days away and there remains the usual inherent uncertainty
farther out in time, SPC has not yet assigned any formal/official
severe risk areas to our domain, but fully suspect that at least
Marginal-to Slight risks will ultimately be assigned to each of
these three days as they get closer, barring some pretty
substantial changes in current expectations. It is far too soon to
really talk details, but at this point it looks like a fairly
"typical" early summer hail/damaging wind threat along with
locally heavy rainfall in spots.

3) Temperature trends will feature an upward trend followed by a
slight cool down toward next weekend. More specifically, highs
Monday are aimed upper 70s-low 80s, then climbing and peaking
roughly around 90 both Wed-Thurs (Wednesday perhaps the slightly
hotter of the two) before easing back more so into the low-mid 80s
for Fri-Sat behind a weak cold frontal passage. After our recent
respite from higher summer dewpoints/humidity, we will also see
these factors climb up into the more humid/sticky category
especially for Tuesday-Thursday with when the most widespread
dewpoints well into the 60s are expected. So, all in all, nothing
unusual at all for early summer.

Normally would go into some more day-to-day specifics before
ending, but running short on time and will simply give this very
general overview of the larger-scale/synoptic weather pattern:
In short, we start out in continued northwest-flow aloft Monday,
then followed by a transition to several days of more quasi-zonal
(west-east flow) from Tuesday onward. This is actually a pretty
typical summer weather pattern, featuring periodic shortwave
troughs/disturbances to kick off thunderstorm activity, along with
a decent combination of instability/shear for potential severe
storms, again mainly Tuesday evening-Thursday night.


.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Sunday)
Issued at 615 PM CDT Sat Jun 24 2017

VFR conditions are expected at both terminals through the period.
While there may be a light sprinkle or two...any sprinkles should
have little impact on operations as they are not expected to be
accompanied by CIGS below 10Kft or reduced visibilities.
Otherwise...expect breezy westerly winds this afternoon to
gradually diminish through the evening hours as winds begin to
decouple...with mainly light and variable winds expected tomorrow
as an area of surface high pressure slides south across the
central plains.




SHORT TERM...Pfannkuch
LONG TERM...Pfannkuch
AVIATION...Rossi is the U.S. government's official web portal to all federal, state and local government web resources and services.