754 
FXUS63 KGID 080005
AFDGID

AREA FORECAST DISCUSSION
National Weather Service Hastings NE
705 PM CDT Tue Jun 7 2022

...Aviation Update...

.DISCUSSION...(This evening through Tuesday)
Issued at 400 PM CDT Tue Jun 7 2022

The main concern in the near term forecast is the probability of 
strong to severe thunderstorms impacting the forecast area this 
afternoon and evening.  Visible satellite imagery shows cumulus 
across the area and a boundary moving from north to south toward the 
Kansas-Nebraska border.  As a note, cloud cover has limited our 
ability to warm up today in many areas which may put a dent in a bit 
of the severe weather potential.  Environment is fairly unstable 
right now and mid-level lapse rates are expected to be around 8+ 
C/km through the evening.  Additionally, 0-6km bulk shear values of 
around 45-55kts, and 0-3km bulk shear values around 30-40kts will 
support supercell development with the potential for some bowing 
segments or a semi-disorganized line of storms forming.  Large hail 
up to at least two inches in diameter and wind gusts up to 75 mph 
will be possible.  Additionally, an isolated tornado cannot be 
entirely ruled out.  

Another topic of concern is the potential for heavy rain and flash 
flooding.  Soil saturation is a concern in several locations due to 
heavy rainfall over the past few days.  Precipitable water values 
are expected to range from 1.00-1.50 inches through the course of 
this event.  Additionally, moisture is being advected into the 
region.  One to two rounds of storms may move through a few areas, 
bringing heavy rainfall areas that have received a decent amount of 
rain.  Any additional heavy rainfall raises the concern for flash 
flooding.  A Flood Watch will be in effect beginning this evening 
and continuing through Wednesday morning for Furnas, Harlan, 
Phillips, Rooks, and Osborne counties.  

Light winds, moisture in the area and cooling temperatures may 
result in the development of some patchy fog overnight.  Expect some 
reductions to visibility in areas where fog does occur. 

Wednesday brings a welcome break from the rain for those who have 
experienced flooding.  A mid-level ridge moves across the Rockies 
and Bighorns into the region.  High temperatures will be fairly 
pleasant, ranging from the mid to upper 70s.  Lows will be in the 
mid to upper 50s.

Thursday brings our next chance for showers and storms as a mid-
level wave moves across the area.  A few storms may become strong to 
severe.  Temperatures will be in the mid-70s to low 80s for highs 
and the mid-50s to low 60s for lows.

Friday and Saturday have trended drier as a ridge moves in from the 
west and high pressure sets up over the south.  Through the weekend, 
temperatures will be on a gradual warming trend with highs returning 
to the upper 80s to low 90s in the afternoon.  Uncertainty grows in 
the extended forecast over the potential for a few isolated 
thunderstorms.

&&

.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Thursday)
Issued at 705 PM CDT Tue Jun 7 2022

General overview: 
For the majority of the period, high confidence VFR
ceiling/visibility and dry conditions. The BIG exception will be
right away this evening, as particularly sometime during the
01-04Z time frame features a decent chance of thunderstorms
(possibly severe). Aside from any thunderstorm-related
influences/outflow, winds should not be a major issue, with
sustained speeds largely near/below 12KT throughout, initially out
of the east-northeast this evening, and then prevailing north-
northwesterly through most of the period (especially Wed daytime).

Thunderstorm potential/timing:
By far the main concern of the period is a decent chance for
thunderstorms this evening, possibly severe. Have a generic
"vicinity" (VCTS) going through 06Z, but have confined a TEMPO
01-04Z to account for the MAIN window of opportunity for storms.
Should any storms be severe, hail to 1+" diameter and/or 50+KT
gusts cannot be ruled out, but actually realizing either of these
conditions at KGRI/KEAR is still a fairly low probability 
scenario at this point. 

Ceiling/visibility:
Although ceiling and/or visibility could at least briefly become
sub- VFR during thunderstorms this evening, confidence is
reasonably-high that at least the vast majority of the latter 18
hours of the period should prevail VFR. There are various "hints"
that at least brief MVFR ceiling could develop especially within a
few hours either side of sunrise Wednesday, but with confidence
only medium at-best have gone with only a scattered low cloud
group. There is probably also a non-zero chance for light fog/sub-
VFR visibility late tonight/early Wed, but believe there should be
just enough of a northerly breeze to hold sub-VFR at bay.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...Flood Watch through Wednesday morning for NEZ082-083.

KS...Flood Watch through Wednesday morning for KSZ005-017-018.

&&

$$

DISCUSSION...Wekesser
AVIATION...Pfannkuch