326
FXUS63 KTOP 161934
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
234 PM CDT Thu May 16 2024

.KEY MESSAGES...

-An isolated storm is possible this afternoon near and south of I-35
 where a surface boundary remains in place.

-Hot and humid weather builds in for the weekend with temperatures
 approaching 90 degrees.

-Severe storms will be possible late Sunday, and again on Tuesday.

&&

.DISCUSSION...
Issued at 227 PM CDT Thu May 16 2024

At 19Z, a weak surface boundary was located across east-central KS.
Water vapor imagery shows a mid level trough axis approaching the
Great Lakes region and a mid level cyclonic circulation over New
Mexico. Near and ahead of the surface boundary, instability had
increased to around 1500 J/kg early this afternoon, but shear is
very weak. The boundary will continue to slowly sag southward
today. Some CAMs show isolated storm development south of the
boundary. Given weak shear, weak convergence along the front
and a lack of mid level forcing, have kept POPs in the low
category mainly near and south of I-35 this afternoon. There is
a signal from models for the redevelopment of patchy fog tonight
and early Friday morning with mainly clear skies and light
winds. The mid level low over New Mexico is expected to pass south
of the area tomorrow, so conditions should be dry through the
day.

A storm system traversing the northern CONUS will bring a weak front
into northeastern KS on Saturday. Surface based instability will
build to over 2000 J/kg near and ahead of the boundary during the
afternoon, but shear again looks to be on the weak side. Without
another source of lift, the chance for storms is low. If any storms
manage to develop, however, they will be the pulse variety. The
front then moves northward as a warm front on Sunday as stronger
southerly flow reinforces a warm and humid air mass over the region.
Temperatures look to approach 90 degrees through the weekend and
early next week.

Models show a series of shortwave troughs moving over the central US
within southwesterly flow aloft late this weekend and early next
week. The first could produce rain and a few storms early Sunday,
but the better chances will be north of the forecast area. The
next shortwave moves out over KS Sunday afternoon/evening,
likely triggering thunderstorm development in central KS. Storms
are expected to progress eastward with time. Severe weather
will be possible with this round given the unstable nature of
the air mass in place.

A more amplified system is then forecast to eject out over the
High Plains on Tuesday. A surface low and associated cold front
should move through northeast KS sometime during the day
Tuesday. Timing will have an impact on the potential severity of
thunderstorms. It currently appears that the better chance for
severe weather will be just east of the area during the
afternoon and evening. Model trends will be monitored for
possible changes to timing.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1225 PM CDT Thu May 16 2024

Ceilings have been scattering at KTOP and KFOE early this
period, and VFR should prevail at all sites by mid afternoon.
There is another signal for patchy fog development tonight and
early Friday morning. Confidence is high enough to at least introduce
reduced visibilities for a few hours early Friday. Timing and
extent of fog may still need to be tweaked in the 00Z period.
VFR then returns with light winds shifting slightly from a south
to a southeasterly direction.

&&

.TOP WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

DISCUSSION...Teefey
AVIATION...Teefey