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fxus63 kgid 242334 
afdgid

Area forecast discussion
National Weather Service Hastings NE
634 PM CDT Sat Aug 24 2019

Update...
issued at 634 PM CDT Sat Aug 24 2019

Tornados watch 616 remains in effect for the SW 1/3 of the County Warning Area.
Admittedly the risk for a tornado over our County Warning Area is low. It's
greatest over wrn Kansas. The cells that are dvlpg from lbf-mck-nrn-
hys are doing so along the northwest-southeast oriented instability gradient...
and moving into an area that has been overcast all day...I.E.
Significantly less instability. So while an isolated brief svr
tstm can't be completely ruled out...the greatest risk may
actually be more rain. We will cont to monitor.

&&

Short term...(this evening through sunday)
issued at 240 PM CDT Sat Aug 24 2019

Still dealing with lingering rain and isolated storms slowly
working east across the forecast area this afternoon. Rain is
associated with sharp, slow moving wave dumb belling its way
across Nebraska/Kansas. Trend has been to slowly weaken the last
couple hours but there is still a few more hours of rain/isolated
storms mainly east of Highway 281 in Nebraska.

To the west, some clearing has found its way into the area and
pushed temperatures to the upper 70s. Water vapor seems to show
more defined spin of wave moving southeast through northeast
Colorado now and this will be a focus for thunderstorms late this
afternoon. Short term convection models continue to focus
thunderstorm development late this afternoon in southwest Nebraska
and northwest/north central Kansas. There is some mid-level
activity but that is dying as it moves east into subsident area
behind wave and into modest mid-level lapse rates. Storm Prediction Center enhanced
severe risk in cornered in the far southwest forecast area. That
if fine for now as there is some uncertainty on how far east those
storms may develop. This could be a little later show by a couple
hours...but the models are consistent in taking the storm quickly
to the south/southwest. Initiation area is key...and the far
southwest forecast is on the edge. Have kept the higher storm
chances there and across the south as a result.

Sunday looks mainly dry...although not a great drying day with
lots of clouds and moisture throughout the day.

Regarding the Flash Flood Watch...have dropped areas north of
Grand Island for expected lack of rain. Have added Mitchell and
Jewell counties for potential for tonights storms to impact that
area. Extended the rest of the watch til 4 am, mainly to account
for thunderstorm which would impact north central Kansas. Further
north, toward I-80 heavy rain is less likely for sure, but not
confident enough to remove the watch just yet, given many areas
received 1-3" of rain today.



Long term...(sunday night through saturday)
issued at 240 PM CDT Sat Aug 24 2019

Sorry for very limited expose' into the longer term but here are
the highlights.

Next frontal boundary and associated upper trough push through
between about 10z and 18z Monday. Models have been more aggressive
with quantitative precipitation forecast and coverage of showers and thunderstorms and pops in
the 50 percent are in the forecast. This front moves through the
forecast by midday, but not before bring unneeded rain to many
locations.

That front comes via northwest flow, and models have been
advertising for days a drying trend with lower dewpoints and
northwest flow. This appears to be setting up Monday through
Thursday. This is actually some really pleasant weather with
dewpoints in the 50s...lows in the 50s and highs in the 70s. The
forecast may not reflect a completely dry scenario, but this is
definitely a much drier period.

Finally, European model (ecmwf) and GFS both advertise another wave/front late
Thursday and Friday. The GFS is quicker (18-24 hours) and the
European model (ecmwf) much wetter. At any rate, the precipitation chances increase
late in the week again.

&&

Aviation...(for the 00z kgri/kear tafs through 00z sunday)
issued at 634 PM CDT Sat Aug 24 2019

Significant wx: IFR conds move back in tonight.

Tonight: vrbl MVFR-VFR this eve with sct-nmrs shwrs. There is a
chance for a rumble of thunder or two. With cigs mostly hanging
around 1500 ft at 2330z...cigs should quickly descend back to IFR
this eve as temps cool. Cigs will lower further to LIFR with
light fog dvlpg as dawn approaches. Southeast winds around 10 kt.
Confidence: high

Sun: LIFR cigs and light fog to start...but vsbys should improve
by 15z with cld bases lifting to MVFR by 18z and eventually VFR by
21z. Southeast winds 10-15 kt. Confidence: high

&&

Gid watches/warnings/advisories...
NE...Flash Flood Watch until 4 am CDT Sunday for nez060>062-072>075-
082>085.

Kansas...Flash Flood Watch until 4 am CDT Sunday for ksz005>007-017>019.

&&

$$

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