Forecast Discussions mentioning any of "ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 08/03/19

Area Forecast Discussion

National Weather Service Hastings NE

 725 PM CDT Fri Aug 2 2019

.SHORT TERM...(This evening through Saturday)
Issued at 353 PM CDT Fri Aug 2 2019

Aloft: Upr-air data from RAOBs and aircraft and RAP tropopause
analyses showed that the flow over the CONUS was dominated by a
large subtropical high over NM with a ridge extending into the
Canadian Prairies. Trofs were along the Pac NW coast and along the
Appalachians. Anticyclonic NW flow was over NEB/KS. A wk mid-lvl
shrtwv trof extended from ND-KS. This trof will diminish further
as rounds the high into the lwr MS Vly by 00Z/Sun.

Surface: High pres was over the GtLks. A barely noticeable
stationary front extended acrs the Gulf Coast states to wk low
pres along the KS-OK border. Another wk low was over SD. This low
will dissipate tonight while the KS-OK low gradually sinks into
Nrn TX by 00Z/Sun. Meanwhile...the wk GtLks high will gradually
shift to the W and extend into NEB.

Rest of this afternoon: Partly to mostly cldy. The mdls hv been
struggling with the nebulous forcing. The main concern on this
shift has been the persistent low-echo-centroid convection
affecting Valley county with flash flooding. The echoes hv been
very persistent. 88D estimates pockets of 4-8" may hv occurred. We
won`t know for sure until the gauge reports come in. We hv
received reports of water over county roads.

PWAT is around 2". These are incredibly efficient rainers with
warm rain processes dominating.

Can`t rule out isold shwrs popping up elsewhere...but despite the
lack of a cap...the lack of forcing may keep much from happening
outside of what`s already in progress.

Tonight: Partly cldy during the eve. Can`t rule out isold shwrs
and possibly a tstm or two. Somewhat begrudgingly left a mention
of precip in the fcst...but believe most locations should remain
dry. Conds are fvrbl for fog and low stratus to reform. MAV MOS
has been insistent for the last 5 runs that widespread fog will
form with vsbys in some areas 1/4 mi or less. We may need to issue
a Dense Fog Advy.

Sat: A foggy start for most if not all the area. It could be
dense. Skies should eventually become partly cldy...but as it
erodes from the edges...there could be a swath that remains mostly
cldy for much of the day.

Did maintain a mention of precip...but it will probably be dry.

.LONG TERM...(Saturday night through Friday)
Issued at 353 PM CDT Fri Aug 2 2019

Aloft: Moderately-amplified anticyclonic NW flow Sun will
deamplify Mon as a fairly potent low mvs thru the Canadian
Prairies. This will cause heights to fall and cyclonic WNW flow
over NEB/KS as the subtropical high gets suppressed and shoved
back into the W a bit. The flow will become less cyclonic mid-late
next wk...but remain from the WNW.

Surface: A cool front associated with the Canadian Prairies low
will move thru Mon. Another cool front is fcst to mv thru Thu. In
the interim...wk high pres.

Temps: averaging a little cooler than normal.

Pcpn: Isold tstms will be psbl Mon with the FROPA. Thereafter...
the mdls are suggesting isold tstms here and there...but
predictability and confidence are extremely low. Overall...the
chance of rain is not good. Most locations will remain dry.

&&

.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Saturday)
Issued at 719 PM CDT Fri Aug 2 2019

Significant wx: IFR CIGs/VSBYs likely.

Tonight: Mixed VFR/MVFR/IFR conditions next few hrs, with VFR/MVFR
the most prominent through 04Z. CIGs will deteriorate around 06Z
with eventually some fog developing by 09Z, which will probably
fall to 1/2 to 1 mi through dawn. Winds will be lgt out of the ESE
before going lgt and vrbl late. Confidence: CIGs - high, VSBYs -
medium.

Saturday: IFR to MVFR. IFR CIGs/VSBYs expected to start the day
with gradual improvement by mid to late morning. Should see primarily
MVFR CIGs for the aftn, but VFR isn`t out of the question. Winds
will be SE around 5-10kt. Confidence: Medium.

&&

.HYDROLOGY...
Issued at 353 PM CDT Fri Aug 2 2019

We need to watch the N Loup Rvr Basin as svrl inches of rain fell
this aftn. That water will be working its way down thru Valley/
Greeley/Howard counties. Water lvls will be rising for sure. We
may need to issue Areal Flood Wrngs for the N Loup Rvr and the
creeks that drain into it.

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

&&

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

$$

SHORT TERM...Kelley
LONG TERM...Kelley
AVIATION...Thies