625
FXUS63 KTOP 101037
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
537 AM CDT Fri May 10 2024

.KEY MESSAGES...

- Pleasant weather persists into Saturday.

- Confidence in showers and thunderstorms on Mother`s Day is
  increasing, but shouldn`t be a complete washout.

&&

.DISCUSSION...
Issued at 236 AM CDT Fri May 10 2024

07Z water vapor imagery showed a cutoff low over the four
corners region as a shortwave dug south through the middle MS
river valley and another shortwave over southern Manitoba.
Surface obs showed high pressure centered over the northern
Rockies and ridging south through the central and southern
plains. Deep moisture was shunted to the gulf coast along a
frontal boundary. A weak surface trough was noted over the
eastern Dakotas and western MN.

Through Saturday, the forecast area is progged to stay between the
cutoff low to the west and the shortwave energy passing through the
Upper Midwest while surface ridging inhibits a return of deeper
moisture. Recent runs of the HRRR hint at a weak boundary moving
through northeast KS this evening with isolated showers along the
front as shortwave energy digs into WI. But the 00Z HREF keeps the
probabilities for showers below 10 percent and the deterministic
solutions fail to generate any QPF as the boundary passes through.
So the lack of good moisture advection or organized forcing should
keep the forecast dry into Saturday with just some mid and high
clouds. Models show 925mb and 850mb temps warming a degree or two
today and again Saturday. So highs are expected to be a few degrees
warmer with good insolation and deep mixing of the boundary layer.

By Sunday afternoon and into Monday, there is good agreement in the
operational models for the closed low to the west to rejoin the main
westerlies and open up as it propagates east over the plains. Some
models suggest moisture return ahead of this wave could be hampered
by surface ridging over the Red River. But the consensus still shows
surface dewpoints increasing into the middle 50s to around 60. This
may be enough for some modest instability around 1000 J/kg by Sunday
afternoon. But 0-6km bulk shear is progged to be around 20KT to
30KT. So we may need to keep an eye on isolated intense storms but
an organized severe risk appears to be a low chance or less than
10 percent. Timing showers and storms should have the better
chances during the afternoon and evening as the better forcing
is progged to lift across eastern KS. Although some guidance is
showing light QPF developing Sunday morning.

Operational models suggests a break in precipitation chances Tuesday
in the wake of the initial upper wave and before a second wave
Wednesday and Thursday. The NBM shows increasing spread in the
various solutions by Wednesday, so precip chances range from 30 to
50 percent. There is not a strong signal for cold or warm air
advection through the end of the forecast period, so temps are
forecast to remain in the 70s for highs and 50s for lows.

&&

.AVIATION /12Z TAFS THROUGH 12Z SATURDAY/...
Issued at 537 AM CDT Fri May 10 2024

Weak surface ridging and a lack of forcing is expected to keep
VFR conditions in place.

&&

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

&&

$$

DISCUSSION...Wolters
AVIATION...Wolters