Area Forecast Discussion
Issued by NWS Dodge City, KS

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FXUS63 KDDC 172033

Area Forecast Discussion
National Weather Service Dodge City KS
333 PM CDT Wed May 17 2017

...updated discussion...

.SHORT TERM...(This evening through Thursday)
Issued at 333 PM CDT Wed May 17 2017

The short term period will only discuss up through Thursday morning.
Thursday convective potential will be discussed in the long term section.

For tonight, tranquil weather is expected as a cold front continues
to sink southward across the greater region. We will see cooler lows
as a drier airmass advects in the wake of the front. 40s northwest
to 50s southeast. No precipitation is expected for the rest of tonight
and into the morning hours.

.LONG TERM...(Thursday night through Wednesday)
Issued at 333 PM CDT Wed May 17 2017

Attention then turns to Thursday afternoon and evening. A very complicated
weather scenario whose convective evolution is not clear at this time.
On paper, a synoptic system will approach the region that will give
SW Kansas another round of severe convection. The cold front mentioned
in the short term period will return northward as a warm front. How
far this warm front makes it north is the main question. This will
have huge implications in where CAPE will develop/be located in the
warm sector. Feel the NAM is probably too aggressive with the movement
of the front. The EC and the ARW look more reasonable with the front
bisecting a portion of the forecast district. Attention should be given
to where this front will be located tomorrow afternoon. If a supercell
can actually sustain itself without turning into a messy hp supercell,
the tornado potential could be locally higher along the front.

As mentioned above, have a few concerns on convective evolution. Fairly
cold 500-hPa temperatures around -16C will be flirting with our western
zones. This is colder than the average -12C for this time of year.
This could create large CAPE, however, convection could also start
earlier compared to model solutions. This would complicate the tornado
potential later in the evening. Some of the mesoscale models actually
show this scenario with convection developing first out west, closer
the 500-hPa cold pool and developing large cold pools. Speaking of
the western zones, will have to watch out for severe potential with
1000 J/kg CAPE and 50-70 kt of shear. Could see a low topped supercell
in the NW zones.

Have much higher confidence of more significant severe weather across
the southeastern near the dryline to the SSW and the bisecting warm
front. Some models indicate CAPE of 2000-3000 J/kg (higher if you believe
the NAM). 0-1 km 200-300 m2/s2 SRH from the EC is also concerning along
with 0-1 km shear of 25-35 kt forecast in the southeastern zones. Overall,
low level shear will be more favorable for tornadoes in the SE if convection
does not initiate too soon or turn into messy hp supercell structures.
There is less backing in the upper level winds progged tomorrow than
compared to yesterday, so we might see less hp supercells and more
classic supercells. This is, however, is speculative, because storm
scale evolution details will not be clear until tomorrow with sfc obs
and satellite/WSR-88D trends.

Putting this all together, the SE zones will have the highest chance
of severe if the warm sector placement from the ARW and EC is correct.
Giant hail of 2-4", a few tornadoes, and 60-80 mph outflows will be
possible tomorrow afternoon and evening. Lower magnitude severe threats
could also be possible across far west-central Kansas earlier.

For the rest of the forecast period, ran with fb grids with no modifications.


.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1200 PM CDT Wed May 17 2017

VFR expected today and tonight. IFR conditions possible for KHYS/KDDC
tomorrow morning as moisture returns. Overnight LLWS is also possible
for KLBL via a LLJ. NW winds today becoming E tomorrow.


DDC  50  79  52  71 /   0  70  60  40
GCK  49  72  48  68 /   0  70  40  30
EHA  50  71  46  68 /   0  40  20  20
LBL  51  78  49  72 /   0  30  30  20
HYS  49  66  53  66 /   0  70  80  50
P28  53  85  59  75 /   0  70  80  60




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