Area Forecast Discussion
Issued by NWS Topeka, KS

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FXUS63 KTOP 160921

Area Forecast Discussion
National Weather Service Topeka KS
421 AM CDT Fri Mar 16 2018

.SHORT TERM...(Today and tonight)
Issued at 420 AM CDT Fri Mar 16 2018

Early this morning a narrow mid-level ridge was shifting east of the
area as an embedded shortwave within the western-U.S. deep mid-level
trough pivoted into western Kansas. Water vapor imagery and surface
obs showed the surface and mid-level lows tracking into western
Kansas with an associated warm front extending eastward across far
northern Kansas.  Southeasterly surface winds south of the warm
front supported some moisture advection and continued WAA into the
region.  Water vapor imagery showed a weak embedded wave developing
over eastern Kansas ahead of the advancing shortwave. This wave
combined with some of the increased moisture, modest isentropic
lift, and some weak elevated instability supported the development
of scattered showers and isolated thunderstorms across northeast and
east central Kansas.  As the mid-level low progresses east-
northeastward, it will help to shift this scattered precipitation
into far northeast Kansas after sunrise.

As the surface low advances toward the CWA today, models show the
warm front remaining fairly stationary across far northeast Kansas
through much of the daytime hours and an associated cold front
tracking from central to east central Kansas during the afternoon
hours.  With the eastward-progressing surface low, winds will begin
to veer to the southwest late morning through this afternoon, which
will help to advect drier air into central and east central Kansas.
These dry conditions combined with breezy winds and dry fuels will
result in very high to extreme fire danger conditions across that
area, so a Red Flag Warning remains in effect. See the Fire Weather
Discussion below for further details.  With the warm front remaining
stationary across far northern Kansas today with southerly winds
across much of the CWA, expect decent WAA into the region and have
increased temperatures a bit with highs reaching into the mid 60s to
mid 70s for locations south of the warm front.  Along and north of
the warm front, expect a sharp temperature gradient due to the
increased, so highs will likely stay in the 50s.

As this drier air gets advected into the region today, the better
moisture will get shunted into northeast to far east central Kansas,
becoming co-located with the better forcing as the surface low tracks
across far northern Kansas.  Ahead of the advancing dryline, models
show some relatively weak instability developing with CAPE values of
500 to maybe 1000 J/kg.  But with decent deep shear present, this
instability should be enough to support some scattered thunderstorm
development along and ahead of the advancing cold front this
afternoon. However, with models showing a relatively narrow-zone of
this marginal instability, better organized storms will likely
remain confined to that region as it shifts northeastward across the
CWA. Cannot rule out the possibility of a few strong to marginally
severe storms developing, with hail being the primary hazard.
However, with backing winds across far northeast Kansas with the
placement of the warm front and advancing surface low, an isolated
brief tornado also cannot be ruled out this afternoon.  As the
surface low lifts northeastward out of the CWA overnight, lingering
precipitation across far northeast Kansas will exit by the early
overnight hours. The shift to northwesterly winds behind the front
will allow low temperatures to drop into the 30s tonight.

.LONG TERM...(Saturday through Thursday)
Issued at 420 AM CDT Fri Mar 16 2018

Sfc and upper ridge will produce a dry day on Saturday with light
north winds and daytime RH values in the 35-55% range. The next
storm system will move into the central Rockies on Sunday with low
pressure at the sfc forecast to move east along the KS/OK border.
The current track of the system would favor the best chances for
rains across the southern half of the state mainly Sunday night into
Monday. The longwave pattern will amplify into the middle of next
week with a trough/ridge/trough pattern across the CONUS.
That would mean more dry weather with near avg temps during the


.AVIATION...(For the 06Z TAFS through 06Z Friday night)
Issued at 1147 PM CDT Thu Mar 15 2018

Southeast winds at the 1500 to 2000 feet range will continue to
increase to 40 to 45 KTS and if surface winds remain from the
east-southeast at 10 to 13 KTS then there may be 30 KTS of low-
level shear in the lowest 2000 feet. The southerly winds will
bring a stratus deck with MVFR ceilings and scattered rain
showers to the terminals later Tonight and through the morning
hours. The showers will end by late Friday morning. Scattered
showers and potential an isolated thunderstorm will redevelop
Friday afternoon and may affect the KFOE and KTOP terminals.
Surface winds will also increase to 13 to 16 KTS with gusts of
20-25 KTS through the day Friday but will switch to the west by
late Friday afternoon and early evening.


Issued at 420 AM CDT Fri Mar 16 2018

A decent pressure gradient will be in place today as a surface low
tracks eastward across Kansas.  As a dryline moves across central to
east central Kansas late morning through this afternoon,
southeasterly winds will veer to the southwest and become breezy
with gusts of 25-35mph expected.  This southwesterly flow will
advect warmer and drier air into the area with highs south of the
warm front soaring into the mid 60s to low 70s and dewpoints
dropping into the 30s.  These conditions combined with dry fuels
will support very high to extreme fire danger conditions across much
of central to east central Kansas.  As a result, a Red Flag Warning
remains in effect for that region from 10 AM to 8 PM.


Red Flag Warning from 10 AM this morning to 8 PM CDT this
evening for KSZ034>038-054>056-058-059.



SHORT TERM...Hennecke
FIRE WEATHER...Hennecke is the U.S. government's official web portal to all federal, state and local government web resources and services.