653
FXUS63 KTOP 201714
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
1214 PM CDT Thu Jun 20 2024

.KEY MESSAGES...

- Isolated showers and storms may continue through the morning
  hours. Patchy fog may also develop towards sunrise.

- Hot and Humid conditions will develop Saturday into early next
  week.

- There will be a chance for storms Saturday night into Sunday
  morning. There may be slight chances for storms by the middle
  of next week.

&&

.DISCUSSION...
Issued at 251 AM CDT Thu Jun 20 2024

Early this morning a broad upper level trough was located across
the southwest US. An upper jet was lifting out on the east side of
the upper trough across the central high Plains and northern
Plains into the northern Great Lakes where the upper jet phases
with a deeper upper trough across the Hudson Bay region of
Canada. A broad upper level ridge was centered across the Mid
Atlantic States and extended west-southwest into east TX.

A surface front extended from eastern IA, southwest across central
MO into southeast KS, then west-northwest into east central CO.
Isolated showers and storms continue to form north of the front
due to isentropic lift.

Today:

The isolated showers and storms may continue into the mid
morning hours but as the mixed PBL deepens, causing the
isentropic lift north of the boundary to weaken. There will be
a 10 to 20 percent chance that during peak afternoon heating a
few isolated storms may develop across northeast and east
central KS. A few CAMs show a weak perturbation lifting
northeast across eastern KS. If these storms develop, they will
not be organized and will be pulse type storms. Any storms that
does manage to develop will dissipate towards sunset. The low
clouds and some patchy fog should mix out during the mid and
late morning. Afternoon insolation should allow high
temperatures to reach the mid 80s to lower 90s.

The H5 ridge across the Mid Atlantic States and Southeast US
will build westward into the southern Plains. The H5 trough
across the southwest US will fill a bit as it retrogrades
westward off the CA coast by 00Z FRI.

Tonight through Thursday:

The center of the H5 ridge axis across the mid Atlantic states will
retrograde westward across the southern Plains and KS will be on the
norther periphery of the H5 ridge axis.

Look for hot and humid conditions through the period. Highs Friday
will be in lower 90s. Highs Saturday will warm into the upper 90s
across much of the region with a few 100 degree readings across the
the southwest counties. Saturday heat indices may reach the 104 to
109 degree range and a heat advisory will probably be needed for
Saturday afternoon.

The H5 trough off the CA coast will shear
off and the northern section of the H5 trough rounds the
southern Plains H5 ridge axis across NE Saturday night. This may
bring a weak front southward across the CWA Saturday night.
Scattered showers and thunderstorms with may develop ahead and
north of the boundary, with a chance 50-60 percent across
northeast KS. There will not be much relief behind this front as
it will undergo frontolysis under the H5 ridge axis Sunday
afternoon.  Highs Sunday will be a few degrees cooler with
highs in the lower to mid 90s.

Early next week the H5 ridge axis will build westward across the
southwest US with a broad H5 ridge axis extending across the southern
Plains. With the broad H5 ridge axis across the southern Plains and
KS. High temperatures will reach the upper 90s to around 102
degrees both Monday and Tuesday afternoon. Southerly surface
winds will keep he richer moisture in place with dewpoints in
the upper 60s to around 70 degrees. Thus heat indicies will
reach the 105 to 110 degree range.

By mid week we may see a slight cool down as the H5 ridge amplifies
across the southwest US and Great Basin. The mid level flow will
become more northerly and a weak front will push southward with more
low chances for showers and storms to develop Tuesday night
through Thursday. Highs on Wednesday and Thursday will only
reach the lower to mid 90s. Heat indices will cool slightly into
the upper 90s along the NE border to around 100 degrees across
the remainder of the area.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1214 PM CDT Thu Jun 20 2024

VFR TAFs will persist through the period at all sites with light
winds and scattered diurnal cu.

&&

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

&&

$$

DISCUSSION...Gargan
AVIATION...Griesemer