Area Forecast Discussion
Issued by NWS Hastings, NE

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48
000
FXUS63 KGID 262322
AFDGID

Area Forecast Discussion
National Weather Service Hastings NE
622 PM CDT Wed Jul 26 2017

.SHORT TERM...(This evening through Thursday night)
Issued at 403 PM CDT Wed Jul 26 2017

After receiving beneficial rain across much of the area overnight
through the morning hours, cloud cover and below average temps
persisted through the day. However, a narrow break in the clouds
has allowed for some areas to reach into the upper 80s and low
90s. A slow to exit low and associated cold front remain situated
across the area this afternoon with scattered rain showers and
thunderstorms continuing to slowly drift to the east and
southeast.

This activity has remained below severe limits at this time.
Uncertainty remains on whether or not any of this activity will
become strong to severe. The narrow band that extends from
Hastings to Lincoln is entering a region of warmer temps and
increased instability due to a rather persistent narrow break in
the clouds, so it seems reasonable that at least a strong storm
or two could develop with 40 to 50mph wind gusts and nickel sized
hail being the main hazards. Given the slow movement of these
storms locally heavy rainfall will also be possible.

Although scattered redevelopment could occur across much of the area
into tonight, any lingering showers should exit the area
overnight with skies beginning to clear Thursday morning. Although
today was technically "cooler" for some areas, Thursday looks to
be the first "nice" day of what looks to be the beginning of a
stretch of below normal temps across the area with highs in the
80s.

.LONG TERM...(Friday through Wednesday)
Issued at 434 PM CDT Wed Jul 26 2017

General overview of this 6-day period: For those perusing our long
term discussions over the past 24 hours, you will find little
noticeable change in the messaging. It continues to be the case
that: 1) Each one of these days features remarkably similar, near-to-
slightly BELOW normal/average temperature expectations with highs
mainly in the mid-upper 80s and lows mainly in the low-mid 60s. 2)
Literally each day night/period from Saturday onward features at
least a small chance (PoP) for rain/thunderstorms within some
portion of our county warning area (CWA). That being said, none of
these chances carry very high confidence in how they may/may not pan
out, as we are entering a semi-persistent and tricky-to-forecast-
rain weather pattern featuring a quasi-stationary ridge over the
western CONUS, a broad trough over the eastern CONUS, and "us" in
between under rather persistent west-northwest flow mid level flow
aloft featuring the passage of various low-amplitude
disturbances/shortwave troughs.

Some more thoughts more regarding temperatures/dewpoints: Again want
to make it clear that we are NOT talking a transition to a
"refreshingly" cool/dry airmass by any means, but more so simply a
respite from the frequent highs/heat index values well into the
90s/100s on many recent days. It is still mid-summer after all, and
it will still feel like summer, albeit with somewhat less humidity
than late with dewpoints more solidly down in the 60s versus the
more oppressive 70s that have been common especially within our
Nebraska zones on many recent days.

Some more thoughts on rain chances/thunder intensity: While the
majority of advertised PoPs are currently only in the 20-30 percent
range, there are some higher values as high as 50 percent in our
southern/southwest zones mainly late Saturday night into Sunday.
However, want to caution that these seemingly higher chances are
from holding true to reality, as they could reflect some "convective
feedback" in the 12Z GFS model as much as anything truly real. In
addition, want to point out that even our fairly low PoPs from
Monday into Tuesday currently don`t have much support from either
the GFS or the ECMWF, but instead are likely tied mainly to what
appears to be an unusually (overly?) wet 12z Canadian model, which
is one of the models that go into our "Superblend" that initializes
most of the Day 2-7 forecast. The bottom line is this: On many days,
the forecast probably sounds "wetter" than it actually will be. As
for severe thunderstorm chances, although it`s almost impossible to
rule out a "Marginal Risk" type setup or two in this pattern, there
is certainly nothing that stands out as obviously-concerning at this
time, and we will just have to take a closer look at a few of these
setups as they get closer and the details become a little clearer.

With the main points covered, will conclude with some brief day-to-
day specifics for those interested...

Friday daytime-night: These are the only two long term forecast
periods that currently carry a dry forecast CWA-wide, as we feature
a pronounced lack of convective instability and also continue to
remain under the dominant influence of a glancing blow of Canadian
high pressure in the low-levels. While confidence is quite high in
the dry daytime forecast, the late night hours are a little more
questionable and bear watching, as some showers/weak storms "could"
perhaps try creeping into some of our northern/western zones late in
the night. Otherwise, the day should be mostly sunny with east-
southeast breezes around 10 MPH.

Saturday daytime-night: Here begins the multi-day "parade" of fairly
low-confidence rain/thunderstorm chances, but don`t go out of your
way to change any outdoor plans yet. Also, Most of these chances
favor the western half of the CWA versus the east. Breezes mainly
from the south-southeast behind the departing ridge axis.

Sunday-Wednesday: Very much the same story continues throughout all
4 of these days, with off-and-on rain/thunderstorm chances but
nothing that looks overly-solid. The very consistent temperature
regime also continues, with highs mainly mid-upper 80s.

&&

.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Thursday)
Issued at 620 PM CDT Wed Jul 26 2017

Lower clouds will linger through most of the night, but will
remain VFR. Clouds will clear out during the morning hours.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...None.
KS...None.
&&

$$

SHORT TERM...Petr
LONG TERM...Pfannkuch
AVIATION...JCB



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.