Scientific Forecaster Discussion
fxus63 ktop 142333
Area forecast discussion
National Weather Service Topeka Kansas
533 PM CST Thu Nov 14 2019
..update to aviation forecast discussion...
Short term...(this evening through Friday night)
issued at 258 PM CST Thu Nov 14 2019
The short-term portion of the forecast will remain inactive with
the focus being on the warming trend expected into the weekend.
Surface high pressure is residing over Kansas this afternoon.
Temperatures warmed nicely today under sunny skies, with highs about
five degrees shy of averages for mid-November. Conditions will
remain clear through the overnight hours as temperatures fall into
the upper 20s. Some steam fog over area rivers and lakes will be
possible tonight due to the combination of light winds, clear skies,
high surface relative humidity values and warmer than air water temperatures.
Surface high pressure will then slide to the southeast of the area
by tomorrow, which will shift our winds to a southerly direction.
Low level warm air advection coupled with sunny skies will allow
temperatures to warm into the mid 50s tomorrow afternoon. All
combined, the end of this workweek will be a noticeable improvement
over the mid 20 high temperatures we dealt with to start the week.
Long term...(saturday through thursday)
issued at 258 PM CST Thu Nov 14 2019
Heading into the weekend, we'll be in zonal flow to start off
Saturday with a shortwave trough to our west over The Rockies. This
will deepen as it translates eastward into the evening before
passing through the County Warning Area overnight. A weak surface cold front is
associated with this wave as well, and warm air advection ahead of the boundary
should bring temperatures into the mid to upper 50s for the
afternoon. This doesn't look to have much impact on temps for
Sunday, but the passing shortwave could bring some light rain in the
morning. Still have a dry forecast for now as most models don't
generate quantitative precipitation forecast until after the best cva has moved east of the area, in
addition to the surface boundary. GFS/NAM forecast soundings don't
have much lift Sunday morning, and the GFS stays dry through the
profile while the NAM has more low-level moisture, perhaps enough
for a few sprinkles. However, the European model (ecmwf) has consistently had the
best precip chances, although modest, so can't entirely rule out
light rain as you get further east in Kansas. Any rain that occurs
should move out by the afternoon with highs in the low to mid 50s.
Monday leaves US with northwest flow, and a very weak embedded wave
continues to bring light quantitative precipitation forecast through the area during the afternoon
at least in the GFS/ECMWF, but confident in this is low and the nbm
keeps pops less than 10 percent, so maintaining a dry forecast here
as well. Ridging will be in place to our west and translate east,
which will bring warmer temps through Wednesday as highs are
expected to reach the mid 50s in far northeast Kansas to the low 60s
toward central Kansas. A much deeper trough will develop off the Pacific
coast on Wednesday, and this looks like the next notable feature
that may bear closer monitoring in the extended period. There is
some variability in how quickly it deepens into a closed low and how
it tracks and evolves, but Wednesday afternoon into Thursday looks
to be our next best chance to see any substantial rain ahead of a
cold front associated with the system.
Aviation...(for the 00z tafs through 00z Friday evening)
issued at 526 PM CST Thu Nov 14 2019
VFR expected to prevail at ktop/kfoe/kmhk as sfc high pressure
shifts eastward, veering light winds to the south by 17z Friday.
Low lying areas may see shallow fog develop just before sunrise,
especially near warmer bodies of water. Mentioned br at ktop with
lesser confidence in occurrence towards kmhk/kfoe.