FXUS63 KGID 252323

Area Forecast Discussion
National Weather Service Hastings NE
623 PM CDT Wed Apr 25 2018

.SHORT TERM...(This evening through Thursday night)
Issued at 426 PM CDT Wed Apr 25 2018

Although we are certainly not expecting any high-impact weather
during the next 36 hours, the main thing to highlight is that
Thursday daytime will be rather windy behind a passing cold
front, and also feature a chance of fairly brief passing rain
showers/sprinkles. Also, want to state up-front that although it
could get JUST cold enough support some patchy/localized frost
development in spots these next two nights, we have deemed it a
bit too early to issue formal Frost Advisories for our coverage
area (CWA), and will be officially holding off on such products
until after May 1st. This is mainly based on our very slow start
to the growing season/state of vegetation compared to areas
farther to our south/southeast.

Taking a look at the current/recent weather scene as of 330 PM...
Overall, the daytime hours have turned out very much as expected.
The morning featured lingering light showers and plentiful clouds,
but this afternoon has been dry with a steady decrease in clouds
from northwest-to-southeast, with only a few of our far southeast
counties holding onto widespread cloudiness at this time. In the
mid-upper levels, water vapor satellite and short term model data
clearly depict the center of the fairly compact low pressure that
brought our recent rainfall departing southeast across southeast
KS, allowing a brief period of shortwave ridging to build in
behind it. At the surface, broad high pressure (around 1022
millibars) is centered near and especially slightly south of our
CWA. Wind speeds have generally decreased this morning, with most
places currently reporting speeds from 5-15 MPH (a few gusts to
around 20 MPH), generally from a northerly direction. High temps
are still on track to range from the low-60s northwest to mid-50s
far southeast, with most places probably not reaching their true
high until around 6PM.

Now looking ahead forecast-wise through the next 36 hours...

This evening/tonight:
Dry conditions continue as our brief shortwave ridging remains
dominant aloft. Skies this evening will be quite clear, with only
a modest increase in mainly high level cirrus late tonight. At the
surface, high pressure departs southeast, meaning that our breezes
will start the evening very light/variable, but gradually flip
around to southerly over the course of the night, but at speeds no
more than 5-10 MPH. Made little change to low temps, with most
areas aimed into the 35-38 range. As stated in the opening
paragraph, some patchy/limited frost cannot be ruled out, but we
will not start issuing formal Advisories/Warnings for frost/freeze
until after May 1st. Despite the ground being a bit moist from
recent rain, am not currently anticipating fog development/issues

Thursday daytime:
Overall, not as pleasant as today thanks mainly to stronger winds.
In the mid-upper levels, a quick-moving/moisture-lacking trough
will swing across the Central Plains from northwest-to-southeast
over the course of the day. While various models vary on rainfall
potential, there is enough support to carry at least a 10-20
percent chance (PoP) for passing sprinkles/brief rain showers,
mainly in our north half during the morning, and then exiting
through our south-southeast during the afternoon. At this
juncture, would be pretty surprised if the vast majority of the
CWA gets more than a few hundredths of an inch out of this.
Certainly the bigger story during the day will be fairly strong
north-northwest winds surging in behind a well-defined cold front.
Sustained speeds will average 20-25 MPH (briefly higher?)/gusting
30-35 MPH. Keep in mind that these stronger winds will gradually
invade from northwest-to-southeast, and areas especially southeast
of the Tri Cities will not see these stronger winds until late
morning/early afternoon. Sky-cover wise, the day as a whole should
average partly cloudy, but will certainly be mostly cloudy for a
time as the enhanced forcing/possible light rain moves through.
Temp-wise, actually nudged up highs 1-2 degrees, calling for low
60s most areas.

Thursday night:
The gusty north winds from the daylight hours will quickly subside
by sunset, and will average no more than 5-10 MPH form the west-
northwest through most of the night. Under clear skies, low temps
will be similar to tonight in most areas, mainly in the 34-37
range, although a few favored cold spots (including Ord/western
Dawson County) could flirt with the freezing mark. Reiterating one
last time: no frost/freeze headlines until May from our office.

.LONG TERM...(Friday daytime through Wednesday)
Issued at 426 PM CDT Wed Apr 25 2018

General overview of this 6-day period:
There are clearly two main stories on the horizon in the extended

1) Chances for showers/thunderstorms return to various portions
of the outlook area starting Sunday night and lasting through
Wednesday. Although it is FAR too early to have any confidence in
the details, at least for now, our overall highest
rain/thunderstorm chances are focused Monday evening and Tuesday
evening, with lesser chances for rain during the daytime hours
(although the latest models are suggesting that next Wednesday
could be wetter than currently advertised). By this time of year,
most people are probably wondering if these thunderstorm chances
carry some risk of severe weather. The short answer is, POSSIBLY,
but it is far too soon to pinpoint any specifics at this point
given various model differences such as: 1) the exact timing of
small-scale disturbances/waves moving in from the southwest...2)
The amount of low-level moisture/convective instability that will
ultimately be available. That being said, a cursory glance at the
latest GFS suggests that mixed-layer CAPE could climb up to around
2000 J/kg during the afternoon-evening on both Monday-Tuesday, so
at least a low-end severe threat cannot be discounted at this

2) We see the most pronounced stretch of warmth so far this
spring, especially in terms of overnight LOW temperatures. From
Friday onward, each day is expected to see highs in the 70s across
most of the CWA, with a few places possibly touching low 80s
mainly Sun-Tues. Low temperatures will potentially be even more
noticeable to most folks, with readings holding up in the upper
40s Saturday night, and then well into the 50s especially Sunday
and Monday nights.

Other than the thunderstorm chances next week, the only other
foreseeable hazards that we will need to keep an eye on include:
1) Could a few days feature at least "near-critical" fire weather
conditions? This could happen as early as Friday mainly in our
northeast zones, and then perhaps over the weekend mainly in a few
far western counties...2) Could wind speeds mainly Sunday into
Monday become strong enough from the south to approach 30 MPH
sustained/gusts 40+ MPH? The current forecast is not quite this
high, but it could end up there eventually, and if so this will
need added to our Hazardous Weather Outlook (HWOGID) as it gets

With the main points covered, will finish with some brief day-
to-day specifics:

Friday-Friday night:
Although it looks to be a bit breezy from the northwest (speeds
raised about 5 MPH from previous), this will overall be a nicer
day than Thursday with plenty of sun and high temps mainly low
70s. Any chance of patchy frost these next 2 nights will not
continue into Friday night, thanks to milder lows in the upper 30s
to around 40.

Saturday-Saturday night:
Likely remaining dry, as breezes gradually increase from the
southeast and high temps again top out around 70.

Sunday-Sunday night:
It becomes rather windy from the south, but warmer with highs
mainly mid-upper 70s. The majority of these 24 hours should be
dry, but could see some limited thunderstorm activity mainly
Sunday night.

While the EC/GFS both depict a broad large scale trough in the
western CONUS, they vary with regard to specific timing of
smaller-scale features ejecting into the Central Plains from it.
Nonetheless, this pattern supports fairly strong south winds, warm
temps and off-and-on thunderstorm chances, especially during the

Confidence in the details is quite low at this Day 7-8 range, but
if the latest models (especially the ECMWF) end up remotely
verifying, this could be a wetter/cooler day than our forecast
currently depicts, as a stronger disturbance emerges from the
western trough and drags through a surface cold front.


.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Thursday)
Issued at 618 PM CDT Wed Apr 25 2018

VFR conditions are currently forecast for this TAF period. Light
and variable winds currently in place are expected to become more
southwesterly tonight, before a cold front swings through early
tomorrow, bringing a switch to more gusty northwest winds. The
afternoon hours could have gusts near 30-35 MPH. In addition to
the winds, ceilings will be lowering through the period, but at
this point was not confident to go lower than VFR. A few
sprinkles/showers could affect both terminal sites, so do have a
VCSH mention going during the afternoon.


Issued at 426 PM CDT Wed Apr 25 2018

..This is currently projected to be the SECOND-COLDEST APRIL on
record at Grand Island/Hastings..

Based on observations from the first 24 days and forecast
expectations from today through month's end, both Grand Island
and Hastings airports (our two primary long-term climate data
sites) are on pace to have the 2nd-coldest April on record,
trailing only April 1920 in the record books. For those possibly
hoping that we might set a new record for coldest April this
month, the above-normal temperatures anticipated Friday-Monday
are expected to "wreck" this opportunity, and slide April 2018
into 2nd place. Stay tuned for more specific info on this as the
end of the month nears.




SHORT TERM...Pfannkuch
LONG TERM...Pfannkuch
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