Special Weather Statement, NWS Topeka, KS

Area Forecast Discussion
National Weather Service Topeka KS
1244 PM CDT Thu Jul 15 2021

...Update to aviation forecast discussion...

.DISCUSSION...
Issued at 335 AM CDT Thu Jul 15 2021

08Z water vapor imagery and profiler data shows a low amplitude
trough over the central plains with one or two convectively
induced vort maximum likely within the trough. Surface obs show
the low level moisture has spread back to the west along an
inverted surface trough that extends from a surface low over
southwest KS across northern MO.

The main concern for today remains the potential for heavy rainfall
and flash flooding. We have already seen thunderstorms producing
heavy rainfall with rates up to 3 inches per hour. Models show
precipital water values remaining just over two inches across east
central KS while the deep layer flow remains somewhat parallel to
the weak surface trough bisecting the forecast area. So there
remains the potential for slow moving storms tracking over the same
areas as we've already seen this morning. Because of this have
issued a flash flood watch through this evening. As for severe
thunderstorms with hail and wind, models have tended to shift the
axis of higher CAPE to the southeast where there may be more
heating. Meanwhile the deep layer shear remains marginal with 0-6KM
shear values of 20KT to 30KT. Perhaps the bigger uncertainty is
whether this morning's convection holds together and persists into
the daytime hours or will there be redevelopment later today. The
CAMs do not appear to be handling the current convection very well,
and try to show storms redeveloping by early afternoon. With the low
level jet likely feeding high theta-e air into the convective
complex, think it may be able to hang together for a little while.
This may cause more cloud cover and less heating for east central KS
and lowering the risk for severe storms. So while there may be an
isolated storm with some hail and wind, the heavy rain looks to be
the main concern. Highs today are expected to be limited by the
clouds and rain with readings generally in the lower 80s. The upper
trough is progged to slowly push east and south this evening with
not a whole lot of scouring of the moisture. So have some decent
POPs over east central KS through the evening hours. Lows tonight
are forecast to be in the mid and upper 60s with possible stratus
lingering overnight holding temps a little warmer than they otherwise
would be.

For Friday through Monday, northwest to north flow is progged to
persist with some possible disturbances moving through the area.
Moisture may not be as good but with the energy there could be
scattered shower activity so have some chance POPs persisting. Temps
through the middle of next week look to remain mild as surface
ridging continues to nose into northeast KS and the upper ridge
remaining over the west. Temps are likely to trend warmer towards
the end of next week as models indicate this upper ridge propagating
to the east. Tuesday and Wednesday look to be mainly dry with the
deeper moisture pushed to the south and no obvious shortwaves
progged to impact the area.

&&

.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
Issued at 1244 PM CDT Thu Jul 15 2021

Terminals may remain on the northern edge of the main area of
precipitation as it moves ENE over the next several hours but
did keep a tempo for some precip for a few hours. Cigs may be able
to rise to VFR outside of the precip for a few hours but
deteriorating conditions are expected overnight in light winds and
a wet boundary layer.

&&

.TOP WATCHES/WARNINGS/ADVISORIES...
Flash Flood Watch until 10 PM CDT this evening for KSZ021>024-
026-035>040-054>056-058-059.

&&

DISCUSSION...Wolters
AVIATION...65

Hazardous Weather Outlook
National Weather Service Topeka KS
428 AM CDT Thu Jul 15 2021

KSZ008>012-020>024-026-034>040-054>056-058-059-160930-
Republic-Washington-Marshall-Nemaha-Brown-Cloud-Clay-Riley-
Pottawatomie-Jackson-Jefferson-Ottawa-Dickinson-Geary-Morris-
Wabaunsee-Shawnee-Douglas-Lyon-Osage-Franklin-Coffey-Anderson-
428 AM CDT Thu Jul 15 2021

This hazardous weather outlook is for east central...north
central and northeast Kansas.

.DAY ONE...Today and Tonight.

Thunderstorms with very heavy rainfall are likely today. These
storms may tend to move slowly over the same areas producing
several inches of rainfall in a short period of time. Because of
this a flash flood watch has been posted for parts of north
central and northeast Kansas and all of east central Kansas
through this evening. The thunderstorms may also be strong enough
to produce some hail and wind near severe levels. Although this
potential appears to be limited to areas south of Interstate 35.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotters are encouraged to report rainfall amounts over one inch
to the National Weather Service in Topeka.

&&

More detailed information can be accessed at...
http://www.weather.gov/top/sitrep

Wolters

Special Weather Statement
National Weather Service Topeka KS
328 PM CDT Thu Jul 15 2021

KSZ008-152100-
Republic-
328 PM CDT Thu Jul 15 2021

...SIGNIFICANT WEATHER ADVISORY FOR NORTHERN REPUBLIC COUNTY UNTIL
400 PM CDT...

At 324 PM CDT, Doppler Radar was tracking a thunderstorm that is
capable of producing a funnel cloud. Current conditions make it
unlikely that any funnel cloud will lower to the ground or do any
damage. However, people should remain alert and move to a safe place
if a funnel cloud approaches. Please report funnel clouds to the
National Weather Service.

Locations impacted include...
Republic and Munden.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 4000 9746 3991 9741 3982 9788 3998 9793
      4000 9793
TIME...MOT...LOC 2024Z 239DEG 13KT 3996 9767

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