Area Forecast Discussion
Issued by NWS Topeka, KS

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FXUS63 KTOP 031600
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
1100 AM CDT Wed Jun 3 2020

.MESOSCALE DISCUSSION...
Issued at 1048 AM CDT Wed Jun 3 2020

The threat thunderstorm activity has increased for the remainder
of the morning and afternoon...

Latest analysis reveals a pseudo-stationary frontal zone
extending from the TX Panhandle, northeastward through central and
northeast KS. Broad northwesterly midlevel flow resides across
the Central and Northern Plains. 500 mb VWP trends at GID suggest
a very subtle shortwave trough is progressing across northern
KS/southern NE. Albeit very weak ascent, it is proving sufficient
for shower and thunderstorm development across north-central KS.
While this initial activity is elevated, concern is increasing
for severe thunderstorms this afternoon. Extrapolating this
subtle shortwave trough east-southeastward, it should be
positioned across east- central KS by early to mid-afternoon --
corresponding to a timeframe when short-term forecast soundings
suggest little mixed- layer inhibition remaining. As a result,
confidence has increase for convective development this afternoon.
The environment these storms will likely develop within is very
favorable for wet-microbursts and possibly large hail, although a
lack of stronger deep layer shear should limit the hail threat.
Furthermore, Pwat values are 1.5-1.6" across much of the forecast
area, which meets/exceeds the daily max for the 12Z TOP RAOB for
June 3 (1.54"), which will likely result in very heavy rainfall
with any storm. Given the weak wind profile, anticipate any storm
motion will be slow and could result in localized flash-flooding.
Any storms that do develop should dissipate near/shortly after
sunset with additional storm chances overnight as a complex moves
across the area.

&&

.SHORT TERM...(Today and tonight)
Issued at 335 AM CDT Wed Jun 3 2020

Early this morning, mid-level ridging was present over the southwest
US with mainly zonal flow across the northern two-thirds of the
CONUS. At the surface, low pressure was located over Iowa with a
weak attendant surface front slowly moving southeast into
southeastern Nebraska and central Kansas. Temperatures across the
CWA have only fallen into the low 70s; the warm start will allow for
another summer-like day today with highs climbing into the low 90s
and heat indices in the upper 90s. The previously mentioned surface
front will continue its progression to the southeast into the CWA
through the day. Most model solutions indicate the boundary will be
along or just north of Interstate 70 by early this afternoon. A
favorable environment for severe wind and hail will be in place with
forecast soundings indicating 2500-4000 J/Kg of MLCAPE and 1000-1200
J/kg of downdraft CAPE. However, a lack of large scale ascent and
weak surface convergence keep confidence low in convective
development this afternoon.

A better chance for thunderstorms comes tonight into early Thursday
morning as a shortwave ejects across the Plains, providing the
necessary lift for convective initiation. Scattered thunderstorms
are progged to develop in western Kansas and Nebraska, and recent
CAM runs have been consistent in showing these scattered
thunderstorms growing upscale into an MCS and propagating into
eastern Kansas. The main threat with these storms would be damaging
winds before precipitation exits the area near sunrise on
Thursday.

.LONG TERM...(Thursday through Tuesday)
Issued at 335 AM CDT Wed Jun 3 2020

Additional thunderstorms are possible on Thursday afternoon/evening
and again on Friday as two more waves of energy move over the
Plains. Models differ on the timing and coverage of convection with
the cap strengthening as an upper ridge builds in from the west.
A few storms could produce damaging winds and large hail if
convective initiation occurs. After Friday, dry weather is
expected to dominate the weekend, although the heat will persist
with highs in the 90s through early next week. Upper ridging
transitions to the east by Mon/Tues with southerly flow returning
as Tropical Storm Cristobal tracks northward from the Gulf of
Mexico. Will have to monitor the track of Cristobal as remnants of
the cyclone could impact the area by the middle of next week.

&&

.AVIATION...(For the 12Z TAFS through 12Z Thursday morning)
Issued at 546 AM CDT Wed Jun 3 2020

VFR conditions will continue at TAF sites through the day today. Winds
become variable as a surface front stalls across the area by this
afternoon. There is a chance for a few scattered TS this
afternoon, but confidence is too low for inclusion. A better
chance for TS comes late tonight with precipitation ending around
sunrise Thursday.


&&

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

$$

MESOSCALE...Baerg
SHORT TERM...Flanagan
LONG TERM...Flanagan
AVIATION...Flanagan



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