Manhattan, Kansas 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

796
FXUS63 KTOP 111030
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
530 AM CDT Fri Apr 11 2025

.KEY MESSAGES...

- Windy weather if forecast Saturday with southerly winds
  gusting up to 35 mph.

- There is a 20 to 30 percent chance for light rain Sunday
  evening.

- Better chances of rain between 30 and 45 percent are forecast
  for Wednesday.

&&

.DISCUSSION...
Issued at 229 AM CDT Fri Apr 11 2025

07Z water vapor imagery showed an upper trough over the Great
Lakes with a shortwave rotating through the middle MS river
valley. Ridging was noted over the northern Rockies as another
upper trough sent shortwave energy across British Columbia.
Surface obs has high pressure centered over NEB with a cold
front stalled over northeast TX.

For today and Saturday, models show northwest flow persisting with
only week moisture advection. With limited forcing in the pattern,
the forecast is for dry weather. Highs today are forecast to be a
couple degrees cooler with the ridge axis passing through the area.
However full sunshine is expected to help highs make it into the
middle 60s east to the lower 70s west. Temps trend warmer for
Saturday as strong southerly return flow develops. Have increased
wind speeds over the NBM initialization based on pressure gradient
progs from the RAP/NAM/GFS. NAM and GFS progs suggest we could
flirt with winds advisory criteria through the day Saturday. For now
have kept the forecast just below criteria with sustained winds
around 25 mph and gusts up to 35 mph. Will have to keep an eye on
fire weather conditions Saturday with the strong winds. Fortunately
reports from the Kansas Forest Service are that fuels continue to
green up. Additionally the southerly winds should bring some
marginally moist air north so RH values are forecast to remain
around 25 percent or better.

There are a couple concerns with the forecast for Sunday centered
around the timing of another cold front moving through the forecast
area. Most operational guidance shows the front passing through the
area midday with cold air advection increasing through the
afternoon. This makes me question the NBM`s forecast highs in the
upper 80s. This mornings initialization came down a degree or two
which looks to be the correct trend since none of the operational
solutions support temps this warm and the 12Z ensembles showing the
higher probability for highs around 80 degrees. So the current
forecast has highs Sunday in the lower and middle 80s. The second
concern is for precip chances Sunday night. Models show some forcing
for vertical motion passing over the area. But this forcing looks to
be out of phase with the surface front. There may be enough mid
level moisture for some light QPF which is depicted by operational
runs. So have left some small 20 to 30 percent chance POPs in the
forecast for Sunday evening. 12Z Ensembles probabilities suggest
rain amounts will be light.

Northwest flow redevelops late Monday and into Tuesday before
another wave potentially impacts the central plains Wednesday and
Thursday. There is a bit more spread among the ensembles in terms
of the strength and timing of this wave and this is reflected in the
low chance POPs that extend past Thursday. Because of the lower
predictability, have maintained the NBM initialization until a better
consensus develops in the ensembles. Still the 12Z ensembles suggest
the better chances for light precip will be on Wednesday and
Wednesday evening. By Thursday there are more members with no QPF
than there are with some QPF. The northwest flow pattern early next
week is forecast to keep afternoon highs closer to seasonal norms
Monday and Tuesday. Better low level warm air advection is expected
to allow temps to trend warmer into the back half of the workweek
with highs in the middle 70s to around 80.

&&

.AVIATION /12Z TAFS THROUGH 12Z SATURDAY/...
Issued at 530 AM CDT Fri Apr 11 2025

Surface ridging and dry air should keep VFR conditions in place.
Later shifts may need to watch out for low level wind shear
early Saturday morning as the low level jet strengthens.

&&

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

&&

$$

DISCUSSION...Wolters
AVIATION...Wolters