Area Forecast Discussion
Issued by NWS Topeka, KS

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

000
FXUS63 KTOP 211846
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
146 PM CDT Fri Apr 21 2017

.UPDATE...
Issued at 145 PM CDT Fri Apr 21 2017

An area of enhanced winds of 25-35 kts with higher gusts have
developed in the last few hours across south central and east
central Kansas on the backside of our departing first wave of
rainfall. These winds, possibly being driven by an elevated meso-
low, should only persist for a few hours at a given location
before decreasing to 10 to 20 kts.

UPDATE Issued at 1102 AM CDT Fri Apr 21 2017

Have updated the timing of the precipitation for the rest of the
morning and the afternoon given the latest radar trends and high
res guidance. The 12Z TOP sounding shows a sharp H800 dry wedge
with 25 kts of reinforcing NE flow through the layer. Have
delayed the onset of precip across the north until later this
afternoon when deeper forcing with the upper trough approaches the
area.

&&

.SHORT TERM...(Today and tonight)
Issued at 331 AM CDT Fri Apr 21 2017

Early this morning, water vapor imagery was showing two nearby
moisture regions which will be contributing to precipitation chances
today through tonight. One area of moisture moving across western KS
and nosing into north central KS is associated with an embedded
shortwave within an advancing mid-level trough that was stretched
across the Rockies.  The second moisture region was located just
south of the CWA, where showers and scattered thunderstorms had
developed along and north of the nearly stationary front located
across Oklahoma and Arkansas.  Short-range models show that this
precipitation across southeast KS may struggle to reach further
north due to the frontal boundary remaining fairly stationary
through the day.  However, we could see scattered showers and
isolated storms extending into portions of east central KS this
morning into the afternoon hours. The better potential for
precipitation across the CWA will come by late afternoon and through
tonight as the mid-level low tracks eastward across southern KS. The
combination of better forcing and available moisture with this mid-
level low should support scattered showers across most of the CWA by
tonight, with the highest QPF amounts looking to be focused across
east central KS.  There is some model uncertainty with the northern
extent of precipitation coverage near the KS/NE border and how
quickly precipitation will diminish across north central KS
overnight as the mid-level low shifts further eastward.  As for QPF
amounts, locations along and south of I-70 may receive 0.5 to 1.0
inch, with higher amounts of 1.0 to 1.5 inches possible along and
south of the I-35 corridor.  Based on the fast-moving nature of this
system and the current flash flood guidance for the region, do not
anticipate the need for a Flood Watch.  However, cannot entirely
rule out the potential for localized minor flooding concerns across
portions of east central KS.

As for temperatures, with either scattered light precipitation or
nearby precipitation across east central KS today, expect the
associated overcast skies to keep conditions cooler across that
region, so have lowered high temperatures into the low/mid 50s.
Further north near the KS/NE border, high temperatures should reach
into the mid/upper 50s. Despite overcast skies tonight, the shift to
northeasterly winds will keep temperatures cooler tonight with lows
in the low/mid 40s.

.LONG TERM...(Saturday through Thursday)
Issued at 331 AM CDT Fri Apr 21 2017

Have kept isolated to scattered showers on Saturday morning with
upper low moving to our east, and should bring an end to showers for
most of the area by the noon hour, save areas southeast of I35
where a few showers may linger into the afternoon. Amounts from
any residual showers are light, generally less than a tenth of an
inch for the daylight hours. Cooler northeasterly winds will hold
highs in the upper 50s to low 60s. Skies clear and winds get light
for Saturday night, with lows dropping into the middle to upper
30s. Think the warmer ground temperatures and recent rains will
help keep frost at bay, but will need to keep an eye on lows.
After the chilly start, highs rise into the upper 60s on Sunday
afternoon under clear skies and a return to southerly surface
winds. These winds stay up overnight and keep lows in the 40s,
with highs on Monday rising into the 70s. Breezy south southwest
winds are forecast to be sustained near 20 with gusts in the 30s.

Upper pattern for Tuesday/Wednesday has some differentiation in the
longer term guidance, but generally brings weak waves through the
zonal flow and a slight chance to chance for some showers, and
generally in the northern areas.  Better chances come Thursday as a
larger scale upper low over the southwest moves toward the Central
Plains. Will keep thunder chances for Thursday, and could be
favorable for strong storms depending on eventual track and timing.
Highs are generally in the 60s and 70s with overnight lows in the
50s.

&&

.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
Issued at 1231 PM CDT Fri Apr 21 2017

VFR to MVFR stratus will linger through the rest of the day across
NE Kansas with lower CIGs working into southern portions of the
area this afternoon and overnight along with moderate rains. This
rain will linger through the night and depart in the mid morning
hours. Winds will remain from the NE through the period,
generally under 10-15 kts, with higher gusts over 20-30 kts
possible this afternoon behind this first wave of precip in east
central KS (gusts at ICT hit 38 kts in the last hour).


&&

.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...Skow
SHORT TERM...Hennecke
LONG TERM...67
AVIATION...Skow


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.