Area Forecast Discussion
Issued by NWS Topeka, KS

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FXUS63 KTOP 041122

National Weather Service Topeka KS
622 AM CDT WED MAY 4 2016

...Update to aviation forecast discussion...

.SHORT TERM...(Today and Tonight)
Issued at 300 AM CDT WED MAY 4 2016

An upper level trough across the northern Great Lakes early this
morning will amplify as it digs south-southeast across the OH river
valley and into the central Appellation Mountains tonight. This
pattern will keep eastern KS under north-northwesterly flow aloft
through tonight.

A weak surface cold front will pass south of the CWA through the
early and mid morning hours. Winds will switch to the northwest and
north and increase as the boundary layer mixes to 850mb. Winds will
be northerly at 10 to 20 MPH with some gusts to 30 MPH possible
through the early afternoon hours. Winds will gradually diminish
through the late afternoon hour as a ridge of surface high pressure
builds southward across the CWA by 00Z THU. Despite the low-level
CAA the mixing up to 850mb, where temperatures are progged to be 7
to 8 deg C, we should see temperatures warm into the upper 60s to
lower 70s.

Tonight, Clear skies and light winds cause overnight lows to drop
into the lower 40s, with some areas possible dropping into the upper
30s before sunrise on Wednesday.

.LONG TERM...(Thursday through Tuesday)
Issued at 300 AM CDT WED MAY 4 2016

On Thursday the closed upper low pressure over the eastern US
continues dig to the southeast causing an expansive surface high
pressure to track across the region. Into the weekend an upper ridge
builds over the plains as another closed upper low pressure moves
over the southwest US. This ridge will support warm temperatures off
the high terrain to move into the central plains. On Friday and
Saturday high temperatures will reach the 80s, which is not far off
from the records in the lower 90s. During the day Saturday an upper
trough will move over the Great Lakes dragging a front close to the
forecast area. A few of the models bring the front into northern KS
in the evening. Dewpoints are forecasted to reach the upper 50s to
lower 60s within the return flow from the far western Gulf and
eastern Mexico. This along with steep mid level lapse rates will
support high instability. Although the strongest winds aloft remain
either to far to the northeast or closer to the base of the western
trough. Therefore if a storm can develop Saturday evening it could
be strong to severe given the instability, but widespread organized
convection is not as likely.

A strengthening low level jet should support elevated storms
overnight Saturday, which will form in western KS and possibly reach
eastern KS Sunday morning as the jet veers. The upper low pressure
over the central Rockies does not move much keeping the warm front
within the vicinity on Sunday. Large scale diffluence over the warm
front and the approaching dry line into central KS will be the focus
for continued showers and storms on Sunday. Again the instability
looks to be high Sunday afternoon if morning activity can clear out,
while the deep layer shear appears marginal. Even on Monday the
upper low finally ejects out of the Rockies moving the surface low
pressure into central KS. There is a chance for the instability and
shear to possibly support severe storms Monday afternoon, but this
is far out. The upper low eventually moves over the region on
Tuesday although the exact track and strength is uncertain. Main
concern through for this entire system will be several rounds of
strong to severe storms and heavy rainfall, which poses a risk for
more flooding.


.AVIATION...(For the 12Z TAFS through 12Z Thursday Morning)
Issued at 607 AM CDT WED MAY 4 2016

For the 12Z TAFs, VFR conditions hold the entire period. Expect
NNW winds to increase as mixing begins by mid morning. Not
concerned with morning fog near the end of the period, even though
winds do decouple overnight, as the boundary layer continues to
dry out further today.


.TOP Watches/Warnings/Advisories...


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