Area Forecast Discussion
Issued by NWS Hastings, NE

Home | Current Version | Previous Version | Graphics & Text | 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
FXUS63 KGID 142043

Area Forecast Discussion
National Weather Service Hastings NE
343 PM CDT Mon May 14 2018

...The Wx is Improving and will Cont with a Temporary Lull in Rain
Chances before They Pick-up Again Late Week...

.SHORT TERM...(This evening through Tuesday)
Issued at 343 PM CDT Mon May 14 2018

Aloft: The flow was split and contorted with a subtropical high
over the Pac NW...the stationary cut-off low over NV with
confluent flow downstream over the US-Can border (diffluent
blocking high config). Two shortwave trofs will cross the CWA this over CO will move into Neb. The other over W TX
will cross KS. Little will change in this overall config thru
tomorrow. The trof that moves into Neb will combine with a Nrn
stream trof to lower the ridge over the SE USA and the high over
the Pac NW will drift E into MT. A shortwave ridge will build over
Cntrl Plns tonight in the wake of the trofs.

Surface: The front from last Thu that has been stalled from SW-
NE across KS will finally become mobile and sink SE tonight into
tomorrow as downstream heights aloft fall. Weak high pres was
actually over Neb this afternoon. By Tue afternoon this high will
give way to another over the GtLakes.

Rest of this afternoon: variable between p/sunny and m/cldy. Did
maintain a slight (20%) POP for an isolated shwr/tstm thru early
eve E of a line from Osborne-Geneva...but this is a very low
probability. Odds are it will remain dry. Given that I believe it
will remain dry...will pull the mention of severe from the HWO.

An isolated shwr did cross Nrn Buffalo county. Had to insert a low
POP for that. Can`t rule out other shwr development...but it will
be the exception.

Tonight: Uncertainty on cloud coverage. Believe the diurnal
stratocu will dissipate...but there could be some lingering
patches of stratus. If that will lower and expand

There are a couple models that try to bring a little shwr/tstm
activity into Rooks/Osborne/Mitchell counties during the
evening... if it survives from NW KS. Did include a 20% POP "just
in case"...but believe it will remain S of I-70.

Conds are favorable for fog. No air mass change...dwpts remain
fairly high...light winds...decreasing clds. Just not sure how
widespread and how low vsbys will go. GFS MOS/LAMP and HRRR
guidance is surprisingly benign. So kept fog character as patchy.
My concern is temps will radiate past afternoon cross-over temps
by 3F to the E of Hwy 183 and espcly E of Hwy 281.

Lows will be in the 50s...about 5F above normal.

Tue: Patchy fog dissipates by mid-morning. Not sure how much
stratus the day begins with...but that will take some time to
dissipate if there is any. Otherwise...expect a healthy deck of
SCT-BKN stratocu to develop within the remnant thermal trof. SC
will be most numerous before 20Z then decrease to just a
FEW...espcly W and S of the Tri- Cities.

Highs in the 70s. Did increase SW counties to near 80F.

.LONG TERM...(Tuesday night through Monday)
Issued at 343 PM CDT Mon May 14 2018

Aloft: The last 2 runs of global models are tightly clustered on
the summerlike pattern remaining in place thru next weekend due to
the diffluent blocking high over the Wrn USA. The main belt of
Westerlies will remain over Canada. A shortwave ridge will remain
over the Cntrl Plns thru Thu. The low currently over NV will be
replaced by a new low from the Pac. As this low breaks apart...the
flow will become SW Fri-Sat with multiple low-amplitude shortwave
trofs fcst to move thru. A shortwave ridge is then fcst to build
over the Cntrl Plns Sun-Mon as the next Pac low moves onshore in
the W. Another significant feature will be the potent trof Nrn
stream trof that will dive from Cntrl Canada into the GtLakes next

Surface: Weak high pres will remain over the Midwest Wed...
maintaining light return flow here. That return flow will cont as
a lee low forms over SE CO. The Canadian upr trof will drive a
cool front S. The CO low is fcst to move up the front Sat as the
it sinks across the CWA. Strong and cool Canadian high pres will
dive into the Cntrl USA and will be overhead Sun and then drift E

The 00Z EC ensemble supports the above scenarios...suggesting
above average confidence.

Temps: back to above normal Wed-Fri. Turning cooler than normal
Sat-Sun...then returning to near normal Mon.

Precip: The last 2 GEM/GFS runs bring tstms fcst to form over Ern
CO into parts of the CWA Wed afternoon/eve. POPs are in the fcst
but am not buying this because these models have a high QPF bias.
The last 2 EC runs are dry. Dry Thu. Believe the next decent
chance of tstms will occur Thu night into Fri induced by the low-
level jet. More chances of tstms exist Fri night into Sat...but
instability will be shunted SE of the CWA Sat afternoon in CAA.


.AVIATION...(For the 18Z KGRI/KEAR TAFS through 18Z Tuesday)
Issued at 343 PM CDT Mon May 14 2018

Significant Wx: Patchy fog possible late tonight

This afternoon: VFR with SCT-BKN stratocu. N-NNE winds 5-15 kt.
Confidence: Medium

Tonight: Becoming VFR with decreasing clds. Conds will be fvrbl
for patchy fog to develop toward dawn. MVFR VSBYs likely for a
time. There is a chance IFR CIGs/VSBYs could occur...but
confidence is not high enough to include yet. Lgt N winds under
10 kt. Confidence: Medium

Tue thru 18Z: MVFR VSBYs should become unrestricted early...but
MVFR stratocu CIGs should develop by mid-morning before lifting to
VFR CU. NNE winds around 10 kt. Confidence: Medium




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